Pseudoprecocious puberty is the early development of secondary sex characteristics without gametogenesis cheap silagra 100 mg overnight delivery impotence your 20s. It can result from the abnormal exposure of immature boys to androgens and of immature girls to estrogens buy discount silagra 50mg erectile dysfunction treatment michigan. The definition of delayed puberty is the absence of physical signs by age 13 years in girls and 14 years in boys silagra 50 mg discount erectile dysfunction pills australia. This condition can result from constitutional delay of growth in which children are below the third percentile for height and have delayed skeletal maturation. Chromosomal sex or genetic sex is determined at the time of fertilization by the random unification of an X-bearing egg with either an X- bearing or Y-bearing spermatozoon. The second step takes place during early embryonic life with the development of male or female gonads. Finally, gonadal hormones act at critical times to control the differentiation of the internal and external genitalia. The process of sexual development is incomplete at birth, with the secondary sex characteristics and functional reproductive system fully activated at puberty. The female is homogametic (having two X chromosomes) and produces similar X-bearing ova. The male is heterogametic (having one X and one Y chromosome) and generates two populations of spermatozoa, one with X chromosomes and the other with Y chromosomes. The X chromosome is large, containing 80 to 90 genes responsible for many vital functions. The Y chromosome is much smaller, carrying only a few genes responsible for testicular development and normal spermatogenesis. Genetic mutations on an X chromosome result in the transmission of X-linked traits, such as hemophilia and color blindness, to male offspring, cannot compensate with an unaffected allele. Theoretically, by having two X chromosomes, the female has an advantage over the male, who has only one. However, because one of the X chromosomes is inactivated at the morula stage, there is no advantage. Each cell randomly inactivates either the paternally or the maternally derived X chromosome, and this continues throughout the cell’s progeny. In males with more than one X chromosome or in females with more than two, extra X chromosomes are inactivated and only one remains functional. The single active X chromosome of the spermatogonium becomes inactivated during meiosis, and a functional X chromosome is not necessary for the formation of fertile sperm. The oogonium, however, reactivates its second X chromosome, and both are functional in oocytes and important for normal oocyte development. Testicular development requires a Y chromosome and occurs even in the presence of two or more X chromosomes. A 4- to 6-week-old human embryo possesses indifferent gonads and undifferentiated pituitary, hypothalamus, and higher brain centers. The indifferent gonad consists of a genital ridge, derived from coelomic epithelium and underlying mesenchyme, and primordial germ cells, which migrate from the yolk sac to the genital ridges. Depending on genetic programming, the inner medullary tissue becomes the testicular component, and the outer cortical tissue develops into an ovary. Sertoli cells line the basement membrane of the tubules, and Leydig cells undergo rapid proliferation. Primordial follicles, composed of oocytes surrounded by a single layer of granulosa cells, are discernible in the cortex between weeks 11 and 12 and reach maximal development by weeks 20 to 25. Hormones from the fetal testes regulate differentiation of the internal and external genitalia. During the indifferent stage, the primordial genital ducts are the paired mesonephric (wolffian) ducts and the paired paramesonephric (müllerian) ducts. In the genetic male fetus, the wolffian ducts give rise to the epididymis, vas deferens, seminal vesicles, and ejaculatory ducts, whereas the müllerian ducts become vestigial. In the genetic female fetus, the müllerian ducts fuse at the midline and develop into the oviducts, uterus, cervix, and upper portion of the vagina, whereas the wolffian ducts regress (Fig. Peak production of these compounds occurs between weeks 9 and 12, coinciding with the time of differentiation of the internal genitalia along the male line. The ovary does not produce hormones that regulate differentiation of the internal genitalia. The primordial external genitalia include the genital tubercle, genital swellings, urethral folds, and urogenital sinus. The development of male and female external genitalia from primordial structures is illustrated in Figure 38. Androgen-dependent differentiation occurs only during fetal life and is thereafter irreversible. However, the exposure of females to high androgens either before or after birth can cause clitoral hypertrophy. Testicular descent into the scrotum, which occurs during the third trimester, is also controlled by androgens. Disorders of sex development occur when chromosomes, gonads, or development of reproductive anatomy is atypical. However, the extra X chromosome interferes with the development of the seminiferous tubules and Leydig cell proliferation. Such males have small testes, are azoospermic, and often exhibit some eunuchoidal features. In Turner syndrome (45,X), there is no gonadal development during fetal life, and at birth, the external genitalia present as female. Given the absence of ovarian follicles, such patients have low levels of estrogens and primary amenorrhea and do not undergo normal pubertal development, which is when the syndrome may be diagnosed. The failure of ovarian development highlights the importance of two X chromosomes in this process. The external phenotype can range from complete absence of male genitalia to inadequate androgenization of the external genitalia (e. There are a number of genetic defects that can impair testes development with subsequent loss of androgen production. Defects anywhere in the androgen synthetic pathway also impair production of the hormone. Infants with 5α-reductase deficiency have ambiguous or female external genitalia and normal male internal genitalia. Affected individuals are often raised as females but undergo a complete or partial testosterone-dependent puberty, including enlargement of the clitoris-like small penis, testicular descent, and the development of male psychosexual behavior. Partial or minimal androgen insensitivity can result in partial development of the male external genitalia. Defects in ovarian development can result from a number of conditions but is most frequently seen in Turner syndrome (46,X) as discussed above.
Elastic recoil is analogous to a spring in which the lungs and chest wall when stretched recoils back to their unstretched configuration generic 50mg silagra overnight delivery impotent rage definition. At the end of a normal inspiration buy cheap silagra online erectile dysfunction breakthrough, the lungs and chest wall are stretched in equal but opposite directions (Fig discount silagra online master card impotence propecia. The stretched lungs have the potential to recoil inwardly, and the stretched chest wall has the potential to recoil outwardly. These two equal but opposing forces cause the pleural pressure to decrease below atmospheric pressure. Pleural pressure is negative or subatmospheric during quiet breathing and becomes more negative with deep inspiration. Only during forced expiration does pleural pressure become positive or rise above atmospheric pressure. The importance of pleural pressure is seen when the chest wall is punctured (see Fig. The stretched lung collapses immediately (recoils inwardly), and the rib cage simultaneously expands outwardly (recoils outwardly). Because the normal pleural pressure is subatmospheric, air will rush into the pleural space any time the chest wall or lung is punctured, and the pleural pressure will become equal to atmospheric pressure because air moves from regions of high to low pressure. This condition, in which air or gas accumulates in the pleural space and the lung collapses, is known as pneumothorax (see Fig. A pneumothorax occurs with a knife or gunshot wound in which the chest wall is punctured or when the lung ruptures from an abscess or severe coughing. It is important to note that the mediastinal membrane keeps the other lung from collapsing. At the end of expiration, the respiratory muscles are relaxed and there is no airflow. Pleural pressure is −5 cm H O, and transpulmonary pressure is,2 therefore, 5 cm H O [P = 0 − (−5 cm H O) = 5 cm H O]. Only a small pressure change between the mouth and alveoli is required for a normal tidal volume. If inspiration is started from the end of a maximal expiration, the chest wall can be felt to expand during inhalation. At no time, as our lungs fill, do we feel the need to close our epiglottis to keep the air in. One of the basic characteristics of gases, such as air, is that the pressures between two2 regions tend to equilibrate. Therefore, when pleural pressure decreases, transpulmonary pressure increases, and the lungs inflate. Inflation of the lungs causes the alveolar diameter to increase and alveolar pressure to decrease below atmospheric pressure (see Fig. This produces a pressure difference between the mouth and alveoli, which causes air to rush into the alveoli. Airflow stops at the end of inspiration because alveolar pressure again equals atmospheric pressure (see Fig. The sequence during inspiration results in a fall in alveolar pressure causing air to flow into the lungs. During expiration, the inspiratory muscles relax, the rib cage drops, pleural pressure becomes less negative, transpulmonary pressure decreases, and the stretched lungs deflate. When alveolar diameter decreases during deflation, alveolar pressure becomes greater than atmospheric pressure and pushes air out of the lungs. Airflow out of the lungs occurs until alveolar pressure equals atmospheric pressure. Specifically, spirometry measures the lung volumes and airflow during inhalation and exhalation. A spirometer displays a volume–time curve, showing volume (liters) along the Y-axis and time (seconds) along the X-axis (Fig. This volume has the least variability of the measurements obtained from a forced expiratory maneuver and is considered one of the most reliable spirometry measurements. This is rather remarkable because small pressure changes are involved to move this volume of air. Instead, they are measured indirectly using a dilution technique involving helium, an inert and relatively insoluble gas that is not readily taken up by blood in the lungs. After the subject rebreathes the helium–oxygen mixture and equilibrates with the spirometer, the helium concentration in the lungs will become the same as in the spirometer. In practice, carbon dioxide is absorbed and oxygen is added to the spirometer2 to make up for the oxygen consumed by the person during the test. Breathing is a dynamic process involving how much air is brought in and out of the lungs in a minute. Expired minute ventilation is calculated from the amount of expired air per minute and can be represented by the equation: (9) Minute ventilation and expired minute ventilation are the same, based on the assumption that the volume of air inhaled equals the volume exhaled. This is not quite true because more oxygen is consumed than carbon dioxide is produced. Because gas exchange occurs only in the alveoli and not in the conducting airways, a fraction of the minute ventilation is wasted air. For each 500 mL of air inhaled, ~150 mL remains in the conducting airways and is not involved in gas exchange (Fig. Thus, only 350 mL of fresh air reaches the alveoli and 150 mL is left in the conducting airways. Any time gases in the alveoli do not participate in gas exchange; these gases also become part of the wasted air. For example, if inspired air is distributed to alveoli that have no blood flow, this constitutes dead space and is referred to as alveolar dead space volume (Fig. Alveoli that have reduced blood flow exchange less inspired air than normal (see Fig. Dead space volume occurs in the conducting airways and in alveoli with poor capillary circulation. In both cases, a portion of alveolar air does not participate in gas exchange and constitutes alveolar dead space volume. Note that physiologic dead space is the sum of alveolar dead space plus anatomic dead space. Physiologic dead space volume represents the sum of anatomic and alveolar dead space volumes. Alveolar ventilation is the amount of fresh air that participates in alveolar gas exchange. The volume of fresh air per minute actually reaching the alveoli is known as alveolar ventilation ( ). Only alveolar ventilation represents the amount of fresh air reaching the alveoli, and it is the only air that participates in gas exchange. For instance, a swimmer using a snorkel breathes through a tube that increases dead space volume.
The spleen followed by the liver are the should be done to assess the initial dys- Q buy generic silagra 50mg line erectile dysfunction in diabetes mellitus pdf. What is damage control surgery in major be covered with worm blankets or a injuries? What are the types of traumatic Genitourinary trauma medical history cheap generic silagra uk impotence symptoms, Time of last food or drink order silagra in india erectile dysfunction treatment centers, pneumothorax? How will you diagnose and treat closed secondary survey in benign once the patient pneumothorax? A 35-year-old male patient sufered blunt is stabilized during the primary survey and Q. The management plan is the same as in always a constant factor and the other case of a polytrauma patient described injuries may or may not be associated earlier that is Q. Blood urea and electrolytes to assess renal ing urine with progressive distension of care? Conservative measures physical examination and relevant emergency with acute retention of urine. The important causes of hematuria are – patient according to Parkland formula in herniated disc or other lesions. Examination of blood to see the bleeding diabetes are to prevent hypoglycemia To arrive at a defnite diagnosis, a detailed and coagulation time. Cystoscopy – To see the presence of any prevent hyperglycemia and ketoacido- evant investigations are required. Ultrasound examination will detect renal f Oral feeding is started as early as pos- (prerenal or renal). If the patient must c Bladder stones – see vesical stone in the omit a meal, an i. Tis infusion is is to make the euthyroid or near euthyroid synthesis of thyroid hormones and continued during the surgery and in the at operation. The normal thyroid status is hormone levels remain high during postoperative period. Small gut perforation due to typhoid the frst stage of development of peritoni- 2. Questions are asked regarding the clinical and iatrogenic following sigmoidos- the upper abdomen usually following a presentation, pathology and treatment of copy, colonoscopy, etc. If ing free gas (air) under both domes of the ulcers perforate posteriorly, gas is then diaphragm. What is the commonest cause of See ‘perforated gastric or duodenal ulcer’ in pneumoperitoneum? What is the name of the omental patch The patient presents clinically with four rigidity) all over the abdomen, on per- procedure? In what conditions, multiple fuid levels Abdominal distension occurs due to the losporin, e. Dynamic or mechanical small intesti- digestive juices and gas, mainly nitrogen ii. What is the signifcance of pneumoperi- See the chapter 34 on ‘intestinal obstruction’. How will you diferentiate between simple The management will be in the same line and strangulated obstruction? To continue the nasogastric aspiration, patient with acute intestinal obstruction? Obliteration of liver dullness is fairly ϐ See the chapter 34 on ‘intestinal reliable. Chapter 103 X-rays ȋ Ǥ ͳͲ͵Ǥʹ Ȍ which results in a combination of bowel 12. The upper loop falls on the lower loop It is a plain flm of the abdomen and upper occlusion of the main vessels at the base of in an-anticlockwise movement. It is a type of closed loop obstruction and tion, at one and half turn twisting, 2. What are the sites where volvulus can See ‘volvulus’ in the chapter 34 on ‘intesti- distally. Band or adhesion at the antimesenteric if this fails or peritonitis sets in, surgi- Froment’s sign. What is the treatment of compound Water-soluble or barium contrast stops constipation. How does a patient with sigmoid volvulus radiopaque shadow in the right kidney present? What percentage of gallstone and kidney complaining of sudden abdominal pain stones are radiopaque? The distended gut feels like a segment radiopaque but only 10 percent of gall- of pneumatic tire. What is the diferential diagnosis of radio- Ǥ ͳͲ͵Ǥʹ ǣ ϐ c. What are the characteristics of oxalate ȋ Ȍ the lumen of bowel presenting like a stones? What are the characteristics of uric acid Tis is plain X-ray of abdomen and pelvis e. Direct spread occurs from the carci- bladder and remains asymptomatic for a noma of esophagus. Masked type-In this type the patient Tis is a plain X-ray of chest with normal nancy and consists of: presents with symptoms of cystitis and bony contour showing multiple rounded a. Treatment of the pulmonary lesion: senting frequently with symptoms of cannon ball metastasis. What does cannon ball metastasis in chest in case of a solitary lesion or multi- gated to exclude vesical calculus. What investigations will you do to con- Cannon ball metastasis to the lungs rep- ii. What are other important fndings in See ‘vesical calculus’ in the chapter 47 on borne metastasis to the lungs. How will you diagnose pneumothorax on pencil-shaped narrowing at the lower end plain chest radiograph? Sometimes a pneumothorax is more diac sphincter which is shown as a smooth obvious on a flm taken in expiration. The failure of relaxation at the is mediastinal shif and the hemidi- cardiac sphincter is due to loss of ganglion aphragm is ofen fattened. What investigations are done for evalua- ease but having small blebs or bullae at tion of achalasia? What is the treatment of difuse esopha- it be a pleural efusion, blood or pus, 29 on ‘esophagus and diaphragm’. Tis is a contrast flm showing barium Difuse esophageal spasm difers from swallow X-ray of esophagus with irregular achalasia as below.
By N. Aidan. Christendom College. 2019.