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1.
Effect of distension on adrenergic innervation of the rat urinary bladder   总被引:1,自引:0,他引:1  
Summary The effect of distension on adrenergic innervation was investigated in the rat urinary bladder. Bladders were distended for 3 h by forced diuresis and ballon obstruction, and specimens were taken from the bladder dome, body and neck for the demonstration of glyoxylic acid-induced fluorescence of catecholamines. Depletion of catecholamines started after 10 h and was almost complete after 2 days. The fluorescence had recovered part way after 5–7 days and was practically normal after 21 days. Small, intensely fluorescent (SIF) cells in the ganglia continued to leak catecholamines throughout the 21-day study period. The primary clinical success of distension therapy for the treatment of unstable bladder may be at least partly due to a reversible disturbance in the function of the adrenergic nerves, which have an excitatory alpha-adrenergic dominance in such cases, but the persistent leakage from SIF cells raises the question of whether distension causes prolonged disturbances in bladder function.  相似文献   
2.
Studies were done to compare the acute effects of streptozotocin-induced diabetes and sucrose consumption on micturition, bladder mass and contractile responses of bladder strips to field stimulation and contractile agonists. Micturition changes occurred gradually in diabetic rats, reached maximal values within 7 to 14 days, and were accompanied by significant increases in bladder mass after 7 days. Bladder strips from diabetics responded to field stimulation, carbachol and KCl with significantly greater contractions than did those from controls within 7 days. Sucrose-drinking rats had maximal increases in fluid consumption and micturition frequency on the first night after starting treatment. Increases in micturition volumes were slower to develop than in diabetics. Bladder mass was significantly increased 30 and 60 days after starting sucrose treatment. Bladder strips from sucrose-drinking rats responded to field stimulation and carbachol with significantly greater contractions than did those from controls only after 60 days. Monitoring of drinking and micturition patterns established that diabetic rats drink and urinate during both the dark and light cycles. In contrast, control and sucrose-drinking rats drink and urinate principally at night. The results demonstrate that differences in bladder function between diabetic and sucrose drinking rats are apparent during the first month after treatment begins. The data suggest that the effects of diabetes and sucrose consumption on contractile bladder function are related to the diuresis-induced increases in bladder mass.  相似文献   
3.
Intrascrotal adenomatoid tumors   总被引:1,自引:0,他引:1  
Adenomatoid tumors are regarded as uncommon neoplasms of the paratesticular tissues, probably of mesothelial origin. The majority of cases reported have involved the epididymis. We report our experience with 8 cases of testicular tumors and 11 of epididymal adenomatoid tumors during a 13-year period, and review the relevant literature. The incidence of adenomatoid tumors relative to all tumors in the testis was 6.9% (8 of 116), exceeding that of Leydig cell tumors, which were previously believed to be the most common benign testicular neoplasms. The adenomatoid tumors included 38% epididymal tumors (11 of 29). The clinical course of the tumors was benign, without recurrences. Local excision is regarded as the treatment of choice for epididymal and testicular adenomatoid tumors.  相似文献   
4.
Sclerotherapy with 5% ethanolamine oleate was used to treat 102 hydroceles in 100 patients and 63 spermatoceles in 58 patients. Scrotal ultrasound examination was performed before the sclerotherapy and at each followup visit. Of the hydroceles 98% were cured completely and 68% were cured after only 1 sclerosant instillation, while 60% of the spermatoceles resolved completely and 33% partially, with 7% failures. No hydroceles recurred during an average followup of 43 months, whereas spermatocele recurred in 4 patients more than 1 year after successful treatment, with a mean followup of 46 months. Approximately half of the patients experienced pain after treatment, 3 had infection and 2 had hematoma. No changes in the structure or size of the testicles were found by ultrasound during followup. Ethanolamine oleate sclerotherapy is a safe, effective and economical form of outpatient therapy that can be recommended as primary treatment for hydroceles in adults and as an alternative to surgery for spermatoceles with 1 to 3 cysts in elderly men in whom fertility is not important.  相似文献   
5.
198 out of 5220 surgical patients were catheterized because of unexpected postoperative urinary retention. In 39% of cases micturition succeeded after the first catheterization of the overdistended bladder, but 61% (58% of the males and 66% of the females) developed more copolicated voided problems. The volume of fluids given intravenously during anaesthesia, the volume of primary urinary retention and increasing age were predisposing factors for prolonged micturition difficulties. Hospitalization was protracted because of postoperative urinary retention in 21 patients, and for 20 males prostatic surgery was necessary to relieve persistent retention.  相似文献   
6.
Shoulder strain in keyboard workers and its alleviation by arm supports   总被引:1,自引:0,他引:1  
Summary Keyboard work consists mostly of dynamic contractions of the small muscles of the forearms and hands. This is accompanied by continuous activity in the arm, shoulder and neck muscles keeping the head and hand in the correct position. Eliminating the weight from the arm by means of support and the position of the arms influences the electrical activity of shoulder muscles when working at a keyboard. We studied the influence of elbow angle, as well as that of different arm supports, on electrical activity of upper trapezius muscle during keyboard work in healthy workers and persons suffering from shoulder pains. The measurements were carried out in the laboratory. EMG activities, which where measured as mean square root (RMS)-values at every 100-millisecond period in trapezius muscle when working, were lower, the greater the elbow angle. Furthermore electrical activity decreased when subjects used arm supports while working. It is evident that the static load to shoulder muscles can be lowered significantly in keyboard work, when the forearms are at an angle of at least 100 degrees and by using arm supports. The most convienient and ergonomic working position can also be found individually be the method used here.  相似文献   
7.
The effect of hypoxia on the structure and function of the synaptosomal membranes and myelin fraction (glial cells, neuronal cell bodies and axonal membranes) was investigated by measuring Na+,K+-ATPase activity and levels of lipid peroxidation products in cerebral cortical synaptosomal membranes and myelin fractions obtained from newborn piglets. Hypoxic hypoxia was induced and cerebral hypoxia was documented as a decrease in the ratio of phosphocreatine to inorganic phosphate (PCr/Oi) using31P-NMR spectroscopy. PCr/Pi decreased from baseline of2.93 ± 0.76to0.61 ± 0.36 during hypoxia. The synaptosomal membrane Na+,K+-ATPase activity decreased from a control value of56.6 ± 3.7to40.4 ± 6.0 μgmol Pi/mg protein/h during hypoxia. The level of conjugated dienes increased from zero (reference value) to4.5 ± 2.7 nmol/mg lipid and the level of fluorescent compounds increased from23.5 ± 2.2to92.6 ± 46.4 ng quinine sulfate/mg lipid in the synaptosomal membranes during hypoxia. No change in myelin fraction Na+,K+-ATPase activity or levels of lipid peroxidation products were noted. These data indicate that sunaptosomal membranes, rich in polyunsaturated fatty acids, are more susceptible to oxygen free radical mediated lipid peroxidative damage during hypoxia.  相似文献   
8.
9.
alpha-Methylacyl-CoA racemase (Amacr) deficiency in humans leads to sensory motor neuronal and liver abnormalities. The disorder is recessively inherited and caused by mutations in the AMACR gene, which encodes Amacr, an enzyme presumed to be essential for bile acid synthesis and to participate in the degradation of methyl-branched fatty acids. To generate a model to study the pathophysiology in Amacr deficiency we inactivated the mouse Amacr gene. As per human Amacr deficiency, the Amacr(-/-) mice showed accumulation (44-fold) of C27 bile acid precursors and decreased (over 50%) primary (C24) bile acids in bile, serum and liver, however the Amacr(-/-) mice were clinically symptomless. Real-time quantitative PCR analysis showed that, among other responses, the level of mRNA for peroxisomal multifunctional enzyme type 1 (pMFE-1) was increased 3-fold in Amacr(-/-) mice. This enzyme can be placed, together with CYP3A11 and CYP46A1, to make an Amacr-independent pathway for the generation of C24 bile acids. Exposure of Amacr(-/-) mice to a diet supplemented with phytol, a source for branched-chain fatty acids, triggered the development of a disease state with liver manifestations, redefining the physiological significance of Amacr. Amacr is indispensable for the detoxification of dietary methyl-branched lipids and, although it contributes normally to bile acid synthesis from cholesterol, the putative pMFE-1-mediated cholesterol degradation can provide for generation of bile acids, allowing survival without Amacr. Based upon our mouse model, we propose elimination of phytol from the diet of patients suffering from Amacr deficiency.  相似文献   
10.
Web-based virtual microscopy in teaching and standardizing Gleason grading   总被引:6,自引:0,他引:6  
Gleason grading forms the basis of prognostic and therapeutic assessment in prostatic carcinoma despite its subjective nature and substantial interobserver variation. The accuracy of Gleason grading can be improved by the use of educational tools such as reference images. However, conventional microscopy images are of limited educational value because it is neither possible to view the sample at different magnifications nor to navigate into different areas of the specimen. This limitation can be overcome by the use of virtual microscopy, which allows viewing entire digitized microscope slides. We created an interactive Web site ( www.webmicroscope.net/gleason ) featuring a comprehensive set of prostatic needle biopsies as virtual slides, which can be viewed with a standard Web browser (Internet Explorer or Netscape). To evaluate the validity of Web-based virtual microscopy for Gleason grading, an experienced uropathologist (TK) scored a series of 62 biopsies from the original glass slides and 6 weeks later from virtual slides on the Web site using an ordinary desktop computer. The intraobserver agreement was excellent, with identical Gleason scores found in 48 of the 62 cases ( kappa = 0.73). The 14 remaining scores differed only by 1 point on the Gleason scale (2-10). The virtual slides were viewed by 2 other uropathologists (PM and HH), with interobserver kappa coefficients ranging from 0.55 to 0.62, which is within the range of previously reported studies using glass slides. The 3 uropathologists' Gleason scores were included as reference scores on the Web site, which now serves as a publicly open platform for self-testing and learning of Gleason grading. We conclude that Web-based virtual microscopy is a promising new tool for teaching and standardizing Gleason grading.  相似文献   
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