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1.
This experimental study on 15 adult male rats with bilateral epididymovasostomies evaluates a new technique of tubule intussusception as an improved form of end-to-end anastomosis. This paper describes in detail the steps in this technique and offers physiological, anatomical, and histological follow-up after 3 months. With this technique there is a 97% patency rate and a 23.3% incidence of macroscopic spermatic granuloma. Complications are discussed in detail.  相似文献   
2.
The cerebrovascular coupling under neuronal nitric oxide synthase (nNOS) inhibition was investigated in alpha-chloralose anesthetized rats. Cerebral blood flow (CBF), cerebral blood volume (CBV), and blood oxygenation level dependent (BOLD) responses to electrical stimulation of the forepaw were measured before and after an intraperitoneal bolus of 7-nitroindazole (7-NI), an in vivo inhibitor of the neuronal isoform of nitric oxide synthase. Neuronal activity was measured by recording somatosensory-evoked potentials (SEPs) via intracranial electrodes. 7-Nitroindazole produced a significant attenuation of the activation-elicited CBF (P<10(-6)), CBV (P<10(-6)), and BOLD responses (P<10(-6)), without affecting the baseline perfusion level. The average DeltaCBF was nulled, while DeltaBOLD and DeltaCBV decreased to approximately 30% of their respective amplitudes before 7-NI administration. The average SEP amplitude decreased (P<10(-5)) to approximately 60% of its pretreatment value. These data describe a pharmacologically induced uncoupling between neuronal and hemodynamic responses to functional activation, and provide further support for the critical role of neuronally produced NO in the cerebrovascular coupling.  相似文献   
3.
Human vaginal epithelial cells (VECs) from vaginal swabs obtained from normal women or from patients with trichomoniasis were purified, and VEC parasitism by Trichomonas vaginalis was examined. Trichomonads bound equally well to live or dead VECs, and up to 20% of VECs were parasitized. Trichomonal cytadherence of human VECs was time, temperature, and pH dependent. Saturation binding levels of live trichomonads to VECs gave approximately 2 organisms adherent to parasitized VEC. No differences in cytadherence levels were detected by different isolates to VECs from the same patient compared with adherence to VECs from normal individuals. Trypsinized, live T. vaginalis organisms failed to recognize VECs. A ligand assay identified four adhesin candidates, and only organisms without a prominent immunogen on the surface (negative phenotype) cytadhered to VECs and synthesized the adhesins, confirming the results of a recently published report by us on adherence to HeLa cell monolayers (J. F. Alderete and G. E. Garza, Infect. Immun. 56:28-33, 1988). These data show the ability of T. vaginalis to parasitize human vaginal epithelial cells in a specific receptor-ligand manner.  相似文献   
4.
The expression of interleukin-2 receptors (IL-2R) and proliferating cell nuclear antigens (PCNA) were compared for their usefulness as markers of lymphocyte activation. Heterologous polyclonal (anti-bovine IL-2R) and monoclonal (anti-human PCNA) antibodies were used to detect the expression of these molecules on activated deer lymphocytes. Both molecules were co-expressed on blast cells which had been activated with mitogen [concanavalin A (Con A)]. There was detectable up-regulation of IL-2R expression in response to antigen [Mycobacterium bovis-derived purified protein derivative (PPD)] stimulation while PCNA expression mimicked lymphocyte transformation (LT) reactivity. PCNA expression was found to more accurately reflect both antigen- and mitogen-activated lymphocyte activation, as estimated by LT activity. The expression of PCNA was used to identify antigen reactive cells from animals exposed to M. bovis. A very low percentage (1.1 +/- 0.4%) of peripheral blood lymphocytes from non-infected animals could be stimulated to express PCNA by in vitro culture with antigen (PPD). Within the infected group both diseased and healthy, 'in-contact', animals expressed significantly higher levels of PCNA upon antigen stimulation.  相似文献   
5.
Aim. To analyze hemodialysis (HD) treatment of patients with Balkan endemic nephropathy (BEN) from five endemic villages in the South Morava Region of Serbia. Analyses of patterns of incidence may generate hypotheses about the underlying causes of BEN, and prevalence data provide information on the current and likely future burden on health services for managing BEN. Methods. A total of 143 end-stage kidney disease patients (ESKD) with BEN were admitted to the renal replacement program from 1974 to 2004: 121 to HD, 15 peritoneal dialysis, and 7 kidney transplantation. As a control group, 117 patients with other kidney disease (chronic pyelonephritis, glomerulonephritis, and ischemic nephropathy) admitted to HD at the time of BEN patients and matched by age and gender were studied. Results. Most of the BEN patients (93.4%) treated by HD were born from 1917 to 1941. The majority of patients (79.3%) started HD from 1977 to 1991 (period of 15 years). The mean age of BEN patients starting HD treatment was 49.1 years in the period from 1974 to 1978, and increased steadily in the following years, being 72.5 years in the last period of study (2004–2006) The mean survival time of BEN males was 4.70 (95% CI 3.66–5.75) and for females was 5.02 (95% CI 1.47–4.53). Difference between males and females was not statistically significant (log rank 0.14, p?=?0.7, P > 0.5). Mean survival times of 4.84 (95% CI 3.97–5.70) in BEN patients and 3.1 (95% CI 2.78–3.84) in other kidney disease patients were found. Difference between BEN patients and controls was statistically significant (log rank 8.38, p?=?0.0038, P < 0.01). Conclusion. The population of endemic villages around the South Morava River admitted to HD treatment after 1974 was exposed to environmental toxicant(s) from 1917 to 1941. The most intense effect of environmental exposure was in that period, with ESKD in patients in their forties. The exposure to environmental toxicants has diminished, so ESKD of BEN has become less frequent and manifested in the older age, mean 72.5 in the period from 2004 to 2006. Different type of exposure was registered in some other endemic regions in Serbia and abroad.  相似文献   
6.
Breast cancer is a systemic disease with a primarily local component. Besides surgical resection and irradiation of the locoregional tumor setting, central therapeutic aim is the elimination of disseminated micrometastatic tumor cells using cytostatic and/or hormonal treatment. Nevertheless, in the course of time a majority of patients suffer from systemic recurrence in the form of distant metastases. Intriguingly, in this connection, intratumoral cytotoxic T lymphocytes might serve as independent predictors of treatment efficacy and clinical outcome. Loss of immune balance (tumor dormancy) during intensive cross talk between T cells and tumor cells in the bone marrow microenvironment is suggested one reason for distant metastatic relapse. In this clinical context, further supportive therapies become increasingly attractive, taking immunological features of breast cancer cells into special account. The present review aims to dissect bone marrow-derived cellular antitumor immune responses and translational immunologic treatment options regarding their actual relevance to patients’ clinical benefit and their future directions in breast cancer management.  相似文献   
7.
Oxidative stress and inflammation are highly intertwined pathophysiological processes. We analyzed the markers of these processes and high-sensitive troponin I (hsTnI) for mortality prediction in patients on haemodialysis. This study enrolled a total of 62 patients on regular haemodialysis. The patients were monitored for two years, and the observed outcomes were all-cause and cardiovascular mortality. Blood samples were taken before one dialysis session for analysis of the baseline concentrations of prooxidant–antioxidant balance (PAB), total antioxidant status (TAS), total oxidative status (TOS), hsTnI, hsCRP and resistin. The overall all-cause mortality was 37.1% and CVD mortality 16.1%. By univariate and multivariate logistic regression, our findings suggest that good predictors of all-cause mortality include hsCRP and PAB (p?p?p?p?p?=?.001). Our data suggest that hsCRP and PAB are very good predictors of all-cause mortality. For CVD complications and mortality prediction in HD patients, the most sensitive parameters appear to be hsTnI and hsCRP.  相似文献   
8.
We present a case which reports the occurrence of a potential elevation of Tacrolimus (Tac) plasma levels to toxic values in a renal transplant recipient after adding Metronidazole (Met) to the medication regimen. A 30-year old female, status post living-related renal transplant, who was stabilized on Tac 4.5 mg, twice daily, for 4 months, presented to the clinic with diarrhea. We used Microparticle Enzyme Immunoassay (MEIA) to determine Tac trough concentration (trough concentrations 5–10 ng/ml). After 6 days of Met therapy on 1.5 g/d, Tac trough concentration and serum creatinine (sCr) increased to 20.2 ng/ml and 7.8 mg/dl respectively. Met therapy was discontinued, also one dose of Tac was withheld, while daily dose was decreased to 2 mg/d. Four days after Met discontinuation, Tac concentration dropped to 8.7 ng/ml, sCr to 2.1 mg/dl, warranting Tac dose increase to 3 mg/d. Co-administration of Tac with Met may result in elevated Tac concentrations, possibly leading to tacrolimus nephrotoxicity. Clinicians should be aware of this potential interaction and closely monitor Tac concentration and renal function.  相似文献   
9.
10.
Evolutionary studies have suggested that mutation rates vary significantly at different positions in the eukaryotic genome. The mechanism that is responsible for this context-dependence of mutation rates is not understood. We demonstrate experimentally that frameshift mutation rates in yeast microsatellites depend on the genomic context and that this variation primarily reflects the context-dependence of the efficiency of DNA mismatch repair. We measured the stability of a 16.5-repeat polyGT tract by using a reporter gene (URA3-GT) in which the microsatellite was inserted in-frame into the yeast URA3 gene. We constructed 10 isogenic yeast strains with the reporter gene at different locations in the genome. Rates of frameshift mutations that abolished the correct reading frame of this gene were determined by fluctuation analysis. A 16-fold difference was found among these strains. We made mismatch-repair-deficient (msh2) derivatives of six of the strains. Mutation rates were elevated for all of these strains, but the differences in rates among the strains were substantially reduced. The simplest interpretation of this result is that the efficiency of DNA mismatch repair varies in different regions of the genome, perhaps reflecting some aspect of chromosome structure.  相似文献   
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