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91.
Genetic relationships between populations can be studied by comparing genotypic and allelic similarities. This investigation aims to demonstrate that selected autosomal microsatellite markers could be used to study the genetic structures of different populations living in northwest Venezuela, in Zulia State. Seven autosomal systems (CSF1PO, TPOX, TH01, vWA, D7S820, D13S317, and D5S818) were tested by PCR in a multiplex format on 688 different chromosomes from unrelated individuals living in Maracaibo, "Isla de Toas," and "San José de Heras," and from two Amerindian populations from the "Sierra de Perijá," Barí' and Yukpa. Allele frequencies, Hardy-Weinberg equilibria, genetic distances, phylogenetic trees, and ethnic admixtures were estimated. The study shows the existence of a clear genetic difference among these populations in accordance with their historic evolution. The populations of Maracaibo and "Isla de Toas" showed a triracial origin, with a large European contribution, followed by an Amerindian component and a small African component. The indigenous groups, Barí' and Yukpa, showed exclusively an Amerindian component, and "San José de Heras" showed only an African component. These results indicate that microsatellite markers are useful for molecular anthropology in a regional and worldwide context and provide important genetic information about contemporary populations of Venezuela.  相似文献   
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The role the FAS and BCL-2 in the apoptosis of testicular cells in the contralateral testis after unilateral testicular torsion, was investigated. We compared with control group. These experiments were performed in male Wistar rats prepuberal old. FAS and BCL-2 determination is realized in cells cultures of contralateral testis. Flow cytometry and immunohistochemistry studies, using a FAS and BCL-2 specific monoclonal antibody, were utilized to value FAS y BCL-2 expression on testiculaires cells following unilateral testicular torsion. We observed an increase of expression of FAS and decrease of BCL-2 in the contralateral testis in comparison with control group. The present results may indicate that the expression of this molecules is implicated in cellular apoptosis.  相似文献   
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Zusammenfassung Mit dieser Arbeit soll im Zeitalter der Dominanz der oralen Pharmakotherapie bei der Behandlung erektiler Funktionsstörungen eine kritische Übersicht über den aktuellen Stellenwert der operativen Therapie der erektilen Dysfunktion gegeben werden. Als mögliche Therapieoptionen werden die penile Venenchirurgie, die arterielle Revaskularisationschirurgie und die penile Prothesenchirurgie beurteilt.Die Venenchirurgie hat heute aufgrund der Wirksamkeit der oralen und intrakavernösen Therapeutika, bedingt durch den Pathomechanismus der kavernovenösen Insuffizienz und durch die publizierten enttäuschenden Langzeitergebnisse ihren Stellenwert gänzlich verloren. Ähnlich verhält es sich mit den penilen Revaskularisationsoperationen, die heutzutage nur noch bei einem hochselektioniertem Patientengut ihre Berechtigung hat. Wichtige Selektionskriterien sind Patientenalter und Ausschluss eines Diabetes mellitus.Einzig die penile Prothesenchirurgie behauptet gegenüber der medikamentösen Therapie der Erektionsstörungen ihren Stellenwert. Hier überzeugen die guten Langzeitergebnisse, die hohe Patienten- und Partnerinnenzufriedenheit bzw. -akzeptanz und die funktionelle Haltbarkeit der in ihrer Mehrzahl dreiteilig, hydraulischen Implantate.
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The aim of this study was to evaluate the percutaneous nerve evaluation (PNE) test success in patients with nonobstructive urinary retention. A total of 24 PNE tests were performed in patients with nonobstructive urinary retention and in 18 patients, a carbachol test was performed during urodynamics. The diagnosis relating to the acontractile detrusor was also assessed and compared to the outcome of the PNE test. The PNE test was successful in eight of 24 patients (33.3%) with the the highest success rate being observed in patients after hysterectomy (80%). It was successful in five of 12 patients with negative carbachol tests and in three of six patients with positive carbachol tests. We conclude that sacral neuromodulation is an effective treatment option in patients with nonobstructive urinary retention. PNE tests should be performed in all patients with therapy resistant nonobstructive urinary retention, because predictive factors do not exist.  相似文献   
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OBJECTIVE: Priapism is defined as prolonged and persistent erection of the penis without sexual stimulation. Etiologies of this condition are numerous. Treatment of priapism varies from a conservative medical to a drastic surgical approach. Recent findings indicate methylene blue (MB), a guanylate cyclase inhibitor, to be a potential inhibitor of endothelial-mediated cavernous relaxation. This prompted us to assess the feasibility, use and effectiveness of MB in the treatment of priapism. METHODS: 12 patients were treated for priapism. Etiologies were: 10 drug-mediated (PGE(1) or papaverine/phentolamine mixture) after corpus cavernosum injection therapy (CCIT); 1 leukemia-induced, and 1 idiopathic high-flow priapism. The age range for all patients was 13-67 years, the average duration of priapism was 5.5 h after CCIT. MB was administered after blood aspiration of the corpora cavernosa. 5 ml of MB was injected intracavernously (i.c.) and left for 5 min. MB was then aspirated and the penis compressed for an additional 5 min. RESULTS: All patients with CCIT-induced priapism were cured with MB alone. The 2 patients who did not respond to MB underwent i.c. phenylephrine administration and embolization of the pudendal artery, respectively. The etiology and duration of priapism were the strongest predictors for success with i.c. administered MB. The primary side effects were a transient burning sensation and blue discoloration of the penis on injection of MB. The initial baseline erectile status was restored in all patients cured by MB. CONCLUSION: These results confirm that MB is a safe and highly effective treatment agent for short-term pharmacologically induced priapism. The application of MB shows virtually no significant side effects compared to the systemic and local complications induced by alpha-adrenergic agonists.  相似文献   
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The characteristics of specific binding of the ATP-sensitive K(+) (K(ATP)) channel blocker [3H]glibenclamide to forebrain membranes (P(2) fraction, 4 degrees C) obtained from morphine-naive and -tolerant mice were evaluated. Morphine tolerance was induced by osmotic minipumps that released 45 mg/kg/day of morphine subcutaneously for 6 days. This treatment enhanced the antinociceptive ED(50) of morphine without changing its E(max). In morphine-naive animals, (1) both the association and the dissociation of [3H]glibenclamide were biphasic; (2) [3H]glibenclamide was displaced by other sulfonylureas (order of potency: glibenclamide>glipizide&z.Gt;tolbutamide) with pseudo-Hill coefficients lower than unity and biphasic Hofstee plots; and (3) Scatchard plots of saturation experiments were curvilinear, showed a Hill coefficient of 0.81+/-0.04 and suggested the presence of two binding sites with a K(D) of 0.13 and 3.17 nM and a B(max) of 12.30 and 84.47 fmol/mg protein, respectively. By contrast, in membranes obtained from morphine-tolerant animals, (1) the Scatchard plots showed only one population of binding sites with a K(D) of 0.87 nM and a B(max) of 77.99 fmol/mg protein, and the Hill coefficient was very close to unity (0.96+/-0.1); (2) competition experiments (using glibenclamide as displacer) showed a pseudo-Hill coefficient of 0.99+/-0.04; and (3) dissociation experiments showed only one phase of dissociation. These results suggest that [3H]glibenclamide binds to two different sites in membranes obtained from morphine-naive animals, but to only one site in morphine-tolerant animals. Consequently, it seems that morphine tolerance in mice involves adaptive changes in K(ATP) channels.  相似文献   
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