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1.
C F Heyns  M L de Kock  C J Deale 《Urology》1990,35(3):247-249
A fifteen-month-old boy with ambiguous external genitalia was found to have a 46XX karyotype, an ovotestis in the right labioscrotal fold, and an absent left gonad. He also had a rudimentary uterus and fallopian tubes and a blind-ending vagina lined with squamous epithelium. These features are compared with those more commonly found in true hermaphroditism.  相似文献   
2.
Tissues were obtained from 387 male pig fetuses ranging from 60 to 120 days of gestation. The relative wet mass and water content of the gubernaculum increased during and decreased after the period of testicular descent. The extracellular glycosaminoglycans (GAG) were assayed to determine whether these polyanionic macromolecules are responsible for the increased water content of the gubernaculum. The total GAG/wet tissue mass in the gubernaculum decreased during and increased after descent, while the total GAG/dry mass decreased during and after descent, indicating an accumulation of water during descent, with a loss of water and an increase in less hydrated tissue components after descent. The major GAG fraction in the gubernaculum was dermatan sulfate, but the percentage hyaluronate in the gubernaculum was two times higher than in striated muscle or umbilical cord, indicating that this GAG fraction may be responsible for the increased water content of the gubernaculum, which probably serves to dilate the inguinal canal and scrotum, thus facilitating descent.  相似文献   
3.
Beckmann  CF; Roth  RA; Luedke  MD 《Radiology》1986,159(3):643-645
In 44 patients with one or more calculi in the upper two-thirds of the ureter, single-stage percutaneous nephrolithotomy was performed through a middle or upper calyceal nephrostomy after cystoscopic placement of an occlusion balloon catheter distal to the calculus; in 42, the procedure was successful. The occlusion balloon catheter permitted retrograde opacification of all systems for enhanced renal puncture. In the last 30 patients an attempt was made either to push the calculus upward mechanically or to flush it upward into the renal pelvis with carbon dioxide or dilute contrast material. This was successful in 24 of these patients. Prior overnight occlusion of the ureter by means of ureteral dilatation further facilitates dislodgment of the calculus, which was successful in 12 of 13 patients.  相似文献   
4.
Epidemiological data from the United States of America (USA) indicate that the incidence and mortality of prostate cancer is higher among Black African-American men (AAM) than among White (Caucasian) American men (CAM). Earlier studies suggesting that prostate cancer is relatively rare among indigenous Black men in Africa are probably flawed by underreporting because recent studies indicate that the incidence rates among Black men are similar to those of White men living in Africa. The higher incidence of prostate cancer among AAM has been ascribed to racial differences in genetic susceptibility, dietary factors, or androgen metabolism. However, it may also be due to registration artefacts because in Africa the reported incidence rates of prostate cancer in different countries correlate directly with the per capita gross national product, suggesting improved access to medical facilities is responsible for higher reported incidence rates.

The greater prostate cancer mortality among AAM may result from higher tumour grade and stage and higher serum PSA at presentation, but it has also been suggested that prostate cancer is biologically more aggressive in AAM than in CAM. However, recent studies indicate that tumour grade and stage and serum PSA at presentation are similar in the races, with no difference in survival after multivariate analysis controlling for pretreatment cancer severity. This suggests that the higher prostate cancer mortality among AAM results from socio-economic factors and limited access to healthcare. Black men living inside as well as outside of Africa still tend to present with locally advanced or metastatic prostate cancer due to lack of early detection programmes.  相似文献   

5.
Among the anomalies of testicular descent exstrophy of the testis appears to be the most rare. We describe a full-term male newborn with the right testis and spermatic cord prolapsed from a skin defect at the neck of the scrotum. The cause of the anomaly is unknown.  相似文献   
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We analyzed 3-dimensional (3D) computed tomographic images of the pelvicaliceal system obtained in 25 patients after opacification of the collecting system by retrograde ureteric or intravenous (IV) infusion of sodium iothalamate. 3D images were reconstructed using the data from nonoverlapping 5-mm sections taken on an Elscint 2400 scanner. Factors contributing to poor image quality were: artifacts caused by contrast in the collecting tubules, underfilling or overdistension of the pelvicaliceal system with contrast, movement of the patient and severe hydronephrosis. Satisfactory 3D images of the pelvicaliceal system can be obtained by retrograde ureteric infusion of 5% w/v sodium iothalamate at 20 cm H2O, or by IV injection of 50 ml of 70% w/v sodium iothalamate. Abdominal compression should be applied 10-15 min after the IV injection of contrast, and the computed tomographic examination should commence 20-30 min after the injection. It is imperative that the patient lie completely still and breathe normally to avoid movement of the kidneys. 3D computed tomographic imaging of the pelvicaliceal system may become a valuable adjunct to the preoperative planning and performance of percutaneous nephrolithotomy.  相似文献   
9.
The role of the gubernaculum during testicular descent was investigated in 115 male pig fetuses ranging from 68 to 109 days of gestation. Descent of the testis through the inguinal canal occurred between 77 and 94 days. There was a marked increase in the total and relative wet mass as well as the wet/dry mass ratio of the gubernaculum, denoting an increase in the water content of this structure during descent of the testis. Similar changes were not seen in other fetal tissues. Asymmetrical descent of the testes occurred in seven of the 40 fetuses between 81 and 92 days of gestation. Descended testes had gubernacula with a greater relative wet mass than the gubernacula of undescended testes. These findings indicate that the increase in mass of the gubernaculum plays an important part in testicular descent. An increase in both the DNA content (hyperplasia) and the RNA/DNA ratio (hypertrophy) was noted in the gubernaculum during descent of the testis. Hyperplasia in the gubernaculum occurred at a rapid rate initially and ceased after the completion of descent. Hyperplasia was also seen in the testis and epididymis, but occurred at a slower rate initially, with a rapid acceleration after the completion of descent. Cellular hypertrophy was not noted in the testis and epididymis, but did occur in umbilical cord tissue. If gonadotropins acting via androgen secretion by the testis provide the stimulus for these changes, the observed difference in response between the gubernaculum and testis could be due to a difference in end-organ sensitivity. However, it is also possible that some unidentified non-androgenic gubernaculotropin, possibly secreted by the fetal testis, provides the stimulus for gubernacular growth.  相似文献   
10.
Elevated blood pressure is an important risk factor for renal-, cerebro- and cardiovascular diseases. We used an efficient discordant sib-pair ascertainment scheme to investigate the impact of the distal end of the long arm of human chromosome 5 (chromosomal region 5q31.1-qter) containing genes for the alpha1B and beta2 adrenergic receptors and the dopamine receptor type 1A on variation of systolic blood pressure in young Caucasians. We measured eight highly polymorphic markers spanning this positional candidate gene-rich region in 427 individuals from 55 three-generation pedigrees containing 69 discordant sibling pairs, and calculated multipoint identity by descent (MIBD) probabilities. The results of genetic linkage and association tests indicate that the region between markers D5S2093 and D5S462 is significantly linked to one or more polymorphic genes influencing interindividual variation in systolic blood pressure levels. Since the alpha1B adrenergic receptor and dopamine receptor type 1A genes are located close to these markers, these data suggest that genetic variation in one or both of these G protein-coupled receptors, which participate in the control of vascular tone, plays an important role in influencing interindividual variation in systolic blood pressure levels.   相似文献   
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