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1.
    
 Müllerian duct regression is first apparent in male pouch young of the tammar wallaby (Macropus eugenii) 6–7 days after birth and, as in eutherian mammals, is characterised by a condensation of the periductal mesenchyme into a whorl around the ductal epithelial cells. A decrease in the density of the extracellular matrix was observed in the region of the whorl. In contrast to eutherian mammals no changes were observed in the mean outer diameter of the Müllerian duct during the early stages of regression. The time at which these mesenchymal changes occur corresponds to the period of Müllerian inhibiting substance secretion in the postnatal tammar testis. Accepted: 25 February 1997  相似文献   
2.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
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3.
The use of more than 130 drugs and drug combinations against the alcohol withdrawal syndrome reflects the fact that views on its treatment are far from being unequivocal. Benzodiazepines are the first choice treatment but it should not be disregarded that they have side effects and, above all, a varying risk of dependency themselves. In recent years many trials have focused on carbamazepine in this respect. Its efficacy was proven in various open and double-blind studies, most of them using concomitant sedative drugs, thereby diminishing the reliability of the results. In a double-blind study we compared the efficacy of carbamazepine with that of oxazepam, in 60 in-patients suffering from alcohol withdrawal syndrome. The main rating instrument was the Clinical Institute Withdrawal Scale--Alcohol (CIWA-A). The 7-day trial showed equal efficacy of carbamazepine and oxazepam during the first 5 days and a statistically significant superiority of carbamazepine on days 6 and 7. Four patients in each group had to be dropped from the study due to side effects or after having withdrawn informed consent. There was no decrease in white blood counts under carbamazepine. The experiences with carbamazepine up to now suggest a more widespread use, especially in non-delirious withdrawal states.  相似文献   
4.
Moderate ovarian hyperstimulation syndrome occurred after LA was administered to control menorrhagia in an anephric woman who required hemodialysis. We postulate that women who require dialysis may be at special risk for the development of this syndrome.  相似文献   
5.
The purpose of this study is to identify correlates of dental student stress. Associations between characteristics of dental students and their stress levels are examined, along with the association of stress with drug use and health problems. A total of 300 out of 315 dental students completed a questionnaire that measured the frequency and stressfulness of 31 stressors; drug use; health problems; and student characteristics including Type A behavior, career commitment, demographics, and lifestyle variables. Characteristics that were associated with a higher stress level were a higher level of Type A behavior and lower level of career commitment. Greater stress was also associated with a greater frequency of health problems. The results suggest an interactional stress model in which the personalities and attitudes of students are important mediators of the stress response.  相似文献   
6.
7.
1. We tested the ability of ouabain to cause chronic hyper tension by continuously infusing ouabain for 28 days (mini-osmotic pump implantation; i.p.). The blood pressure and metabolic effects of sham (150 mmol/L NaCI; n= 12) or ouabain infusion (10 μg/kg per day; n= 14; 100 μg/kg per day; n = 14) were examined in conscious Sprague-Dawley rats. 2. Plasma ouabain concentrations measured after 28 days of ouabain infusion were as follows: sham, not detectable (n= 11); ouabain 10 μg/kg per day, 0.60 ± 0.07 nmol/L (n= 14); and ouabain 100 μg/kg per day, 7.17 ± 0.57 nmol/L (n= 14; P < 0.001). 3. Sham or ouabain infusion did not alter food intake, bodyweight, water intake or urine output in conscious rats. 4. Blood pressure was not altered by sham treatment. Ouabain at 10 μg/kg per day or 100 μg/kg per day did not produce consistent rises in blood pressure. Ouabain at 10 μg/kg per day increased blood pressure on treatment day 12 only (+ 6mmHg; P < 0.05), while at 100μg/kg per day blood pres sure increased on treatment days 16 (+ 9 mmHg; P < 0.05) and day 18 (+ 8mmHg; P < 0.05) only. There was no significant difference in blood pressure between sham and ouabain groups. 5. Renal blood flow was decreased in rats infused with ouabain at 10 μg/kg per day (2.0 ± 0.3 mL/min per 100 g body-weight; n= 5; P < 0.01) and 100 μg/kg per day (2.2 ± 0.4 mL/ min per 100 g bodyweight; n= 7; P < 0.05) compared with sham treatment (3.5 ± 0.2 mL/min per 100 g bodyweight; n= 6). Renal vascular resistance was increased in rats treated with ouabain at 10 μg/kg per day (65.5 ± 12.6 mmHg/mL per min per 100 g bodyweight; n= 5; P < 0.01) and 100 μg/kg per day (66.0 ± 15.6 mmHg/mL per min per 100 g bodyweight; n= 7; P < 0.05) compared with sham treatment (32.6 ± 2.5 mmHg/mL per min per 100 g bodyweight; n= 6). 6. High plasma concentrations of ouabain do not cause consistent increases in blood pressure in conscious Sprague-Dawley rats.  相似文献   
8.
Many changes in renal function occur in normal pregnancy. Without a proper understanding of these changes, routine clinical investigations may easily be misinterpreted. Women with preeclampsia have further alterations in renal function and, in occasional cases, develop acute renal failure. Understanding of abnormal renal physiology and hormonal changes in these women allows the clinician to interpret biochemical tests appropriately and make proper use of vasodilator therapy with careful attention to volume homeostasis. Women who undertake pregnancy with a primary renal disease, most commonly glomerulonephritis or reflux nephropathy, have a higher risk of adverse fetal and maternal outcomes. Awareness of these risks provides a basis for proper preconceptual counseling, as well as careful monitoring of maternal blood pressure and renal function and fetal growth during such pregnancies. These strategies will optimize the chances of a successful pregnancy outcome for both mother and baby.  相似文献   
9.
Onchocerca volvulus nodules were removed from 77 fully compliant patients in a longitudinal study of ivermectin treatment in Sierra Leone. The patients had participated in a randomized controlled trial and received either 4 annual doses of ivermectin or 10 6-monthly doses over 6 years. Worms were examined 9 months after the last treatment for evidence of changes in morphology, viability and reproductivity. The findings were compared with results for the 2 groups obtained at earlier surveys of the same study population. Repeated treatment at 6 and 12-month intervals has resulted in a marked ageing of the male worm population profile and a significant reduction in the proportion of live female worms found in the nodules. In addition, there has been a reduction in reproductivity of 90% or more. However, most of the worms found were still alive and potentially fertile, underlining the need for the continuation of regular ivermectin treatment to maintain the benefits achieved.  相似文献   
10.
Recent evidence suggests that a considerable proportion of plasma angiotensin is generated not in blood but in peripheral tissues. Through the measurement of angiotensin peptides and renin in the plasma of 11 anephric subjects, we have investigated whether kidney-derived renin, or some other tissue mechanism for angiotensin generation, is the major determinant of plasma angiotensin. Particular care was taken to prevent inadvertent activation of inactive renin and possible generation, conversion and metabolism of angiotensin peptides during processing of blood samples. Initial experiments revealed that plasma from anephric subjects contains high amounts of material which interferes in radioimmunoassays for angiotensin, even after high-performance liquid chromatography (HPLC). Therefore, in order to obtain an unambiguous identification of angiotensin peptides, a dual HPLC method was developed in which angiotensin peptides were first separated by HPLC, then acetylated and run again on HPLC before radioimmunoassay for angiotensin I and II (detection limits, 0.25 and 0.2 fmol/ml, respectively). The levels of angiotensin I and II were 1.2 +/- 1.6 and 0.7 +/- 0.5 fmol/ml (mean +/- s.d., n = 9-10), respectively, being 6% of levels in normal subjects, and were consistent with the active renin levels (1.8 +/- 1.7 muIU/ml, n = 11) which were 7% of levels in normal subjects. Artefactual activation of prorenin and angiotensin generation during sample processing were excluded as significant causes of the low levels of active renin and angiotensin I and II in anephric plasma. These data indicate that kidney-derived renin is the major determinant of angiotensin levels in normal human plasma. However, the present demonstration of low levels of active renin and angiotensin I and II in plasma of anephric subjects provides unequivocal evidence for a functional extrarenal renin-angiotensin system in man.  相似文献   
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