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81.
The Authors are reviewing their experience of Obstructive Uropathies diagnosed and treated surgically in neonates, the last 8 years in their Institution. 67 cases were reviewed, in which 37 presented with ureteropelvic junction obstruction (UPJ). 13 with posterior urethral valves, 11 with primary megaureter and 6 with ureterocele. Prenatal ultrasonography allowed the diagnosis to be made in two third of the patients. UPJ is the most common obstructive uropathy observed. Posterior urethral valves the most severe because of high pulmonary and renal (dysplasia) complication rate. Surgery, when indicated, has no more complications to be expected than in general population, if oriented prophylactic measures are taken in the early peri- and postoperative period.  相似文献   
82.
Lipodermatosclerosis is a sign of severe chronic venous insufficiency. In this stage of CVI one can find capillary leakage of water and plasmaproteins which results in a higher capillary filtration rate. In skin biopsies the result of this process can be seen as a pericapillary halo. The group of Burnand recently described fibrinogen deposits in this area. We studied the capillaries and their surrounding tissue to determine the thickness of the collagen IV deposits. In severe CVI with lipodermatosclerosis a significant increase of the collagen IV layer was observed. Collagen IV thickness was measured by an index method. The collagen IV thickness for this purpose refers to the capillary diameter. It can be suggested that the increase of the venous pressure in the capillaries leads to leakage of several proteins and namely fibrinogen. As a result of the increase of fibrinogen the collagen IV layer becomes thicker which leads to a decreasing function of the capillaries. In this way an auto-amplification mechanism maintains CVI. An other explanation can be induction of collagen IV due to the high capillary pressure in CVI.  相似文献   
83.
R 75251, a new inhibitor of steroid biosynthesis   总被引:1,自引:0,他引:1  
R 75251, a new imidazole derivative, inhibited the conversion of androgens to estrogens, of progestins to androstenedione and testosterone, and of 11-deoxycorticosterone to corticosterone in human placenta microsomes, subcellular fraction of rat testis, bovine adrenocortical mitochondria, in cultured rat granulosa, testicular and adrenal cells, respectively. In vitro, no effect on cholesterol synthesis and cholesterol side-chain cleavage was found at concentrations up to 10 microM. In rat granulosa cells, no effect on progesterone production was detected. In vitro, no effect on steroid radioligand binding was observed. In male volunteers, a single dose of 300 mg of R 75251 significantly lowered plasma testosterone and estradiol for 24 hours and increased plasma concentration of 17 alpha-hydroxyprogesterone and progesterone. As compared with ketoconazole high dose (600 mg b.i.d), R 75251 (300 mg b.i.d) was at least as efficacious as inhibitor of testosterone synthesis when studied during ACTH stimulation. In contrast to ketoconazole, R 75251 did not significantly affect circulating adrenal androgen levels in male volunteers. Precursors of gluco- and mineralocorticoids such as 11-deoxycortisol and 11-deoxycorticosterone accumulated more than after ketoconazole administration. The data show that the cytochrome P450-dependent aromatase, 17-hydroxylase/17,20-lyase, and 11-hydroxylase are the target enzymes for R 75251.  相似文献   
84.
A rat model of chronic serum sickness was used to study the pathogenesis of progressive glomerulosclerosis complicating experimental immune-complex glomerulonephritis. Chronic serum sickness was induced by immunising rats with bovine serum albumin followed by intraperitoneal administration of the antigen. Early lesions consisted of mesangial deposits of rat immunoglobulins, followed later by transient subendothelial and persistent subepithelial immune aggregates. On the basis of the peak level of proteinuria around day 80, three groups of rats were distinguished: I physiological proteinuria; II 50-500 mg/24 h; and III greater than 500 mg/24 h. The animals were killed at day 220 and the presence of mesangial proliferation, epithelial proliferation, and synechiae, as well as focal glomerulosclerosis was scored. It appeared that all and only proteinuric animals developed progressive glomerulosclerosis, although all three groups of animals passed through a phase with mesangial and subendothelial immune deposits. A strong correlation was found between the degree of proteinuria and the proportion of glomeruli affected. We conclude that the combination of mesangial and subendothelial deposits on the one hand and subepithelial deposits associated with increased protein loss on the other constitute a conditio sine qua non for the development of progressive glomerulosclerosis in this model. The use of specific antibodies to investigate the composition of the sclerotic lesions showed the presence of laminin and type IV collagen, but not of types I and III collagen in sclerotic areas of glomeruli. This indicates that the development of progressive glomerulosclerosis in this model is due to an increased production of glomerular basement membrane components by presumably solely glomerular cells after the occurrence of immunological glomerular injury.  相似文献   
85.
86.
 Smooth pursuit typically includes corrective catch-up saccades, but may also include such intrusive saccades away from the target as anticipatory or large overshooting saccades. We sought to differentiate catch-up from anticipatory and overshooting saccades by their peak velocities, to see whether the higher velocities of visually rather than nonvisually guided saccades in saccadic tasks may be found also in saccades in pursuit. In experiment 1, 12 subjects showed catch-up, anticipatory, and overshooting saccades to comprise 70.4% of all saccades in pursuit of periodic, 30°/s constant-velocity targets. Catch-up saccades were faster than the others. Saccadic tasks were run as well, on 19 subjects, including the 12 whose pursuit data were analyzed, with target-onset, target-remaining (saccade to the remaining target when the other three extinguish), and antisaccade tasks. For 17 of the 19 subjects, antisaccade velocities were lower than for either target-onset or target-remaining tasks. Velocities for the target-remaining task were near those for target onset, indicating that target presence, not its onset, defines visually guided saccades. Error and reaction-time data suggest greater cognitive difficulty for target remaining than for target onset, so that the cognitive difficulty of typical nonvisually guided saccade tasks is not sufficient to produce their lowered velocity. To produce reliably, in each subject, catch-up and anticipatory saccades with comparable amplitude distributions, nine new subjects were asked in experiment 2 to make intentional catch-up and anticipatory saccades in pursuit, and were presented with embedded target jumps to elicit catch-up saccades, all with periodic target trajectories of 15°/s and 30°/s. Velocities of intentional anticipatory saccades were lower than velocities of intentional catch-up saccades, while velocities of intentional and embedded catch-up saccades were similar. Target-onset and remembered-target saccadic tasks were run, showing the expected higher velocity for the target-onset task in each subject. Both experiments demonstrate higher peak velocities for catch-up saccades than for anticipatory saccades, suggesting that cortical structures preferentially involved in nonvisually guided saccades may initiate the anticipatory and overshooting saccades in pursuit. Received: 1 December 1995 / Accepted: 25 February 1997  相似文献   
87.
88.
A 53-year-old male with hepatitis C cirrhosis, who had been refused liver transplantation because of hypertrophic cardiomyopathy (HC), underwent nonsurgical septal ablation using alcohol with resolution of his ventricular outflow obstruction. This patient was able to subsequently undergo a successful deceased donor liver transplantation. This is the first reported case of alcohol induced septal ablation being performed in a cirrhotic patient with HC. Such nonsurgical procedures may be attractive in cirrhotic patients who are refused access to liver transplantation because of high surgical risk.  相似文献   
89.
90.
Purpose. In the National Heart, Lung, and Blood Institute Guidelines for the Diagnosis and Management of Asthma, the expert panel recommends that a written asthma action plan be provided for all patients with asthma. Studies evaluating the usefulness of the asthma action plan in children are limited. We aim to determine exacerbation frequency and usefulness of the asthma action plan in managing exacerbations that occur in a pediatric primary care setting. Methods. Caretakers of asthmatic children attending the general pediatric clinic in an inner-city hospital completed a one-page questionnaire covering topics such as asthma severity, frequency of exacerbations, and possession/usefulness of an asthma action plan. Although controversy exists over the definition of yellow and red zone exacerbations, we defined the yellow zone as symptoms that require albuterol more than three times a day or more than two nights in succession. The red zone was defined as symptoms requiring systemic corticosteroids and/or an urgent physician visit. Results. Seventy of 75 subjects completed the survey. Almost 80% of respondents carried the diagnosis of persistent asthma, whereas the remainder had intermittent asthma. Exacerbation frequency over a 3-month period was determined. Approximately 80% of children experienced at least one yellow zone episode: 42% had one or two yellow zone episodes, and 39.6% had between three and five episodes. Sixty-three percent of patients did not experience a single red zone exacerbation. Almost 75% (44 of 59) of subjects possessed an asthma action plan. Ninety percent (37 of 41) of respondents with action plans found the plan to be useful in managing exacerbations. Conclusion. Approximately four of every five asthmatic children seen in this primary care setting experienced a yellow zone exacerbation at least once during a 3-month period. One third experienced at least one red zone episode. Nine of every 10 caretakers with an action plan reported the asthma action plan to be of value in managing exacerbations.  相似文献   
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