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BACKGROUND: A transient state of azoospermia may occur due to toxic, environmental, infectious or iatrogenic conditions. Finding sperm in the ejaculate of such patients is often unpredictable and may be critical in IVF treatment. In the present study, the approach of pooling and cryopreservation of sperm is evaluated. Cryopreservation was performed in a unique group of patients in whom no sperm had been found in at least one previous sperm examination and in patients diagnosed as suffering from non-obstructive azoospermia in whom, occasionally, sperm were found. METHODS: A total of 157 semen pooling and cryopreservation procedures in 53 patients was performed between January 1998 and December 2000 in our centre. Forty five of these patients underwent an IVF-ICSI treatment during the study period. In 32 patients, fresh sperm were used to perform ICSI. In 13 patients no sperm were available, and the previously frozen sperm were used. RESULTS: Using our pooling system, 13 IVF-ICSI cycles were rescued. In seven patients with a previous testicular biopsy due to azoospermia, sperm cryopreservation was possible. Overall, 13 pregnancies (10 deliveries, two ongoing pregnancies and one missed abortion) were achieved. CONCLUSION: The introduction of semen banking for patients with transient azoospermia may increase the chance of pregnancy using their own sperm.  相似文献   
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Cell adhesion and migration are important features in tumor invasion, being mediated in part by integrins (extracellular matrix receptors). Integrins are significantly decreased in human prostate cancer. An exception is 6 integrin (laminin receptor) which persists during prostate tumor progression. We have selected high (DU-H) and low (DU-L) expressors of 6 integrin from a human prostate tumor cell line, DU145, to assess experimentally the importance of 6 integrin in tumor invasion. DU-H cells exhibited a four-fold increased expression of 6 integrin on the surface compared to DU-L cells. Both cell types contained similar amounts of 3 and 5 integrin. The DU-H cells contained 6 subunits complexed with both the 1 and 4 subunits whereas DU-L cells contained 6 complexed only with 4. DU-H cells were three times more mobile on laminin as compared to DU-L, but adhered similarly on laminin. Adhesion and migration were inhibited with anti-6 antibody. Each subline was injected intraperitoneally into SCID mice to test its invasive potential. Results showed greater invasion of DU-H compared to DU-L cells, with increased expression of a6 integrin on the tumor at the areas of invasion. These data suggest that 6 integrin expression is advantageous for prostate tumor cell invasion.  相似文献   
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International Urology and Nephrology - To quantify the occurrence of stent failure and the dynamic behavior of urine flow in ureter-stent systems, including the relative flow in the ureter and...  相似文献   
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We report on a model of human prostate tumor cell invasion using the SCID (severe combined immunodeficient) mouse diaphragm. Tumor cells were injected into SCID mice intraperitoneally and the diaphragms harvested three to five weeks later. Electron microscopy showed tumor cell penetration of the mesothelial cell layer and adhesion to the underlying basement membrane on the inferior surface of the mouse diaphragm, where colonies developed. Immunohistochemistry showed invasion by tumor cells through the basement membrane into the muscle of the diaphragm, presence of human tumor cells among the muscle cells and the presence of selected proteins on the invasion front of the tumor cells. Digital image analysis enabled quantitative comparison of events in the metastatic cascade by variants of the tumor cell line and evaluation of the effectiveness of a putative tumor inhibitor. Results suggest that the SCID mouse diaphragm model is a convenient, effective, easily oriented and reproducible in vivo model of the early events associated with human prostate tumor cell invasion.  相似文献   
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The Task Force for Creating a Biomedical Communications System for Dermatology was commissioned by the American Academy of Dermatology to develop an experimental segment of a computerized data bank on dermatologic therapy. The Task Force has completed such a "first generation" system and has named it DermRx. Its data bank carries the following information on each entry: the name of the disease; topical, systemic, physical, and other kinds of treatment; caveats; references to the literature; and the date and reviewer(s). The DermLit and DermRx programs are two components of a projected broader concept of an eventual comprehensive Biomedical Communications System for Dermatology. Such a system is envisaged as a means of making available to dermatologists diverse data relevant to practice, teaching, research, and business aspects of the specialty. At the moment, access to the stored information on dermatologic literature and therapy is by telephone call to, or by correspondence with, the central computer facility at Northwestern University. Eventually it is projected to be accessible by dedicated microcomputers housed in the physician's office. This preliminary report on DermRx is presented to review the progress of the project to date and to elicit comment upon its structure and value.  相似文献   
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Soman, a powerful inhibitor of acetylcholinesterase, causes an array of toxic effects in the central nervous system including convulsions, learning and memory impairments, and, ultimately, death. We report on the protection afforded by postexposure antidotal treatments, combined with pyridostigmine (0.1 mg/kg) pretreatment, against these consequences associated with soman poisoning. Scopolamine (0.1 mg/kg) or caramiphen (10 mg/kg) were administered 5 min after soman (1.2 LD50), whereas TAB (i.e., TMB4, atropine, and benactyzine, 7.5, 3, and 1 mg/kg, respectively) was injected in rats concomitant with the development of toxic signs. Atropine (4 mg/kg) was given to the two former groups at the onset of toxic symptoms. Caramiphen and TAB completely abolished electrographic seizure activity while scopolamine treatment exhibited only partial protection. Additionally, no significant alteration in the density of peripheral benzodiazepine receptors was noted following caramiphen or TAB administration, while scopolamine application resulted in a complex outcome: a portion of the animals demonstrated no change in the number of these sites whereas the others exhibited markedly higher densities. Cognitive functions (i.e., learning and memory processes) evaluated using the Morris water maze improved considerably by the three treatments when compared to soman-injected animals; the following rank order was observed: caramiphen > TAB > scopolamine. Additionally, statistically significant correlations (r = 0.72, r = 0.73) were demonstrated between two learning parameters and [3H]Ro5-4864 binding to brain membrane. These results show that drugs with a pharmacological profile consisting of anticholinergic and antiglutamatergic properties such as caramiphen and TAB, have a substantial potential as postexposure therapies against intoxication by organophosphates.  相似文献   
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Focal segmental glomerulosclerosis (FSGS) is a scarring process associated with chronic low‐grade inflammation ascribed to toll‐like receptor (TLR) activation and monocyte migration. We developed synthetic, small‐molecule lecinoxoids, VB‐201 and VB‐703, that differentially inhibit TLR‐2‐ and TLR‐4‐mediated activation and monocyte migration. The efficacy of anti‐inflammatory lecinoxoid treatment on FSGS development was explored using a 5/6 nephrectomy rat model. Five‐sixths of nephrectomized rats were treated with lecinoxoids VB‐201, VB‐703 or PBS, for 7 weeks. Upon sacrifice, albumin/creatinine ratio, glomerulosclerosis, fibrosis‐related gene expression and the number of glomerular and interstitial monocyte were evaluated. Treatment of nephrectomized rats with lecinoxoids ameliorated glomerulosclerosis. The percentage of damaged glomeruli, glomerular sclerosis and glomeruli fibrotic score was significantly reduced following VB‐201 and VB‐703 treatment. VB‐703 attenuated the expression of fibrosis hallmark genes collagen, fibronectin (FN) and transforming growth factor β (TGF‐β) in kidneys and improved albumin/creatinine ratio with higher efficacy than did VB‐201, but only VB‐201 significantly reduced the number of glomerular and interstitial monocytes. These results indicate that treatment with TLR‐2, and more prominently, TLR‐4 antagonizing lecinoxioids, is sufficient to significantly inhibit FSGS. Moreover, inhibiting monocyte migration can also contribute to treatment of FSGS. Our data demonstrate that targeting TLR‐2‐TLR‐4 and/or monocyte migration directly affects the priming phase of fibrosis and may consequently perturb disease parthogenesis.  相似文献   
10.
Background Little is known about the dermoscopic features of scalp tumours. Objective To determine the dermoscopic features of scalp tumours. Methods Retrospective analysis of dermoscopic images of histopathologically diagnosed scalp tumours from International Dermoscopy Society members. Results A total of 323 tumours of the scalp from 315 patients (mean age: 52 years; range 3–88 years) were analysed. Scalp nevi were significantly associated with young age (<30 years) and exhibited a globular or network pattern with central or perifollicular hypopigmentation. Melanoma and non‐melanoma skin cancer were associated with male gender, androgenetic alopecia, age >65 years and sun damage. Atypical network and regression were predictive for thin (≤1 mm) melanomas, whereas advanced melanomas (tumour thickness > 1 mm) revealed blue white veil, unspecific patterns and irregular black blotches or dots. Conclusions The data collected provide a new knowledge regarding the clinical and dermoscopy features of pigmented scalp tumours.  相似文献   
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