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71.
72.
Abdominal hysterectomy after treatment of cervical cancer by radiation therapy is associated with a significant rate of postoperative vesicovaginal fistulas. In this series, five patients with invasive cancer of the cervix treated by radiation therapy developed new cervical or uterine neoplasms 1 to 27 years after treatment. All underwent abdominal hysterectomy without postoperative fistula formation. Success is attributed to cautious surgical technique and to the use of the omental pedicle graft to bring new vascularity to the vaginal apex and bladder base. The technique of forming an omental pedicle graft is described.  相似文献   
73.
Tri-n-butyltin (TBT), one of environmental pollutants accumulated in mollusks, at nanomolar concentrations decreases cellular content of glutathione (GSH), suggesting that TBT increases cell vulnerability to oxidative stress because GSH has a role in catabolizing hydrogen peroxide (H(2)O(2)). In order to examine this possibility, the effect of tri-n-butyltin chloride (TBTCl) on rat thymocytes suffering from oxidative stress induced by H(2)O(2) was examined using a flow cytometer with four fluorescent probes; ethidium bromide, 2',7'-dichlorofluorescin diacetate, 5-chloromethylfluorescein diacetate and annexin-V-FITC. TBTCl at concentrations ranging from 100 nM to 1 μM attenuated H(2)O(2)-induced decrease in cell viability in a dose-dependent manner. It was unlikely that TBTCl reduced H(2)O(2)-induced oxidative stress because TBTCl failed to affect H(2)O(2)-induced oxidation of intracellular molecule (2',7'-dichlorofluorescin) and H(2)O(2)-induced decrease in cellular content of GSH. Results suggest that TBTCl may inhibit the pathway of cell death induced by H(2)O(2) or that TBTCl may induce a protective substance against the oxidative stress produced by H(2)O(2).  相似文献   
74.
Endogenous uveitis is a common cause of visual disability and blindness. The etiology of uveitis remains largely unknown but reasonable etiologic factors include infections. Superantigens are regarded as one of the leading causes of infectious etiology in autoimmune disease. However, the role of superantigens in uveitis remains unclear. In the present study, we investigated the effect of Staphylococcal enterotoxin B (SEB), a member of the superantigens, using an experimental model of autoimmune uveoretinitis (EAU). C57BL/6 mice were immunized with human interphotoreceptor retinoid binding protein (IRBP) peptide, and the severity of EAU disease was scored. Vehicle (PBS) alone or SEB dissolved in PBS was administered by intravenous injection on post-immunization day 10 or on post-immunization day 24. In addition, a systemic immune response study was performed to address the effects of SEB on systemic immunity. EAU was aggravated significantly by the injection of SEB at post-immunization day 10. Furthermore, relapse was induced by the injection of SEB at day 24. On the other hand, SEB injection without IRBP peptide immunization elicited no inflammatory changes in the uvea or retina. Furthermore, SEB enhanced not only the IRBP-specific T-cell proliferative responses but also IFN-γ and IL-17 production. Moreover, the intraocular expression levels of these cytokines was also enhanced by SEB injection. Both anti-CD4 and -Vβ8 Ab administration suppressed disease aggravation and the enhancement of IRBP-specific T-cell responses caused by SEB. These results suggest that SEB is involved significantly in the aggravation or recurrence of endogenous uveitis through activation of autoreactive uveitogenic T cells.  相似文献   
75.
From the stem bark of Ekebergia capensis, 10 new triterpenoid compounds, ekeberins A (1), B (2), C1 (3), C2 (4), C3 (5), D1 (6), D2 (7), D3 (8), D4 (9), and D5 (10), were isolated together with 17 known compounds. The structures of these new compounds were elucidated on the basis of the results of spectroscopic analysis, and the absolute configuration of compounds 6-10 were determined by partial synthesis from known compounds and using the Mosher ester method. Several of these compounds were screened in vitro against both chloroquine (CQ)-sensitive and -resistant Plasmodium falciparum isolates and were found to exhibit moderate antiplasmodial activity, with compounds 20 (7-deacetoxy-7-oxogedunin) and 27 (2-hydroxymethyl-2,3,22,23-tetrahydroxy-2,6,10,15,19,23-hexamethyl-6,10,14,18-tetracosatetraene) showing IC50 values of 6 and 7 microM, respectively. Compound 27 at a dose of 500 mg/kg showed moderate parasitemia suppression of 52.9% against P. berghei NK 65 in a mouse model.  相似文献   
76.
Bioassay-guided fractionation of the root wood of Zanthoxylum wutaiense led to the isolation of 11 new compounds, wutaiensol methyl ether (1), demethoxywutaiensol methyl ether (2), methyl wutaiensate (3), methyl 7-hydroxyanodendroate (4), methyl 7-methoxyanodendroate (5), wutaifuranol (6), 7-methoxywutaifuranol (7), 7-methoxywutaifuranal (8), methyl wutaifuranate (9), methyl 7-methoxybenzofuran-5-carboxylate (10), and wutaipyranol (12), together with another 37 known compounds, of which one, 7-methoxybenzofuran-5-carboxaldehyde (11), was not previously known as a plant constituent. The structures of these isolates were identified by means of spectroscopic analysis. Five of these isolates were found to be antitubercular constituents, namely, methyl 7-methoxyanodendroate (5), 7-methoxywutaifuranal (8), wutaiensal (13), dictamnine (14), and gamma-fagarine (15), which exhibited antitubercular activity against Mycobacterium tuberculosis H37Rv, showing MIC values of 35, 35, 30, 30, and 30 microg/mL, respectively.  相似文献   
77.
78.
We encountered a 10-year-old prepubertal girl with a normal ovary and oviduct torsion. Hemorrhagic infarction of the ovary and oviduct occurred, and these structures were laparoscopically removed. Torsion of the normal ovary and oviduct in a prepubertal girl is discussed.  相似文献   
79.
A patient with ventricular extrasystoles is reported in whom Type A alternating Wenckebach periodicity in the re-entrant path of the extrasystoles is suggested for the first time. Namely, it appears that 2:1 exit block occurs at a proximal level in the re-entrant path and block of the Wenckebach form occurs at a distal level in the path. The presence of three-level block in the re-entrant path is also suggested in this patient.  相似文献   
80.
Primary hepatocellular carcinoma (HCC) in patients <30 years old is extremely rare. In younger patients, HCC develops against a background of persistent hepatitis B virus infection. We herein report a 23-year-old woman with HCC with all-negative hepatitis virus markers developing in an apparently healthy liver. Imaging studies showed a 50-mm hypervascular mass in segment 4 of the left liver lobe, compatible with HCC. The patient underwent surgical resection. A histological examination showed the presence of poorly differentiated HCC. The patient was diagnosed with HCC developing in a healthy liver. This is an extremely rare case of non-B non-C HCC.  相似文献   
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