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961.
榛子叶化学成分研究(Π)   总被引:1,自引:0,他引:1  
目的 对榛子叶中的鞣质成分进行了研究 ,开发利用黑龙江省榛子叶资源。方法 利用 1 H- NMR,1 3C- NMR,FAB- MS,CD谱及 1 H- 1 HCOSY二维谱与化学方法鉴定。结果 从中得到 4个化学成分 :榛叶素 B(heterophylliin B, ) ,tellimagrandin ( ) ,casuarictin ( ) ,casuarinin ( )。结论 榛叶素 B是一个新的鞣花二聚体成分  相似文献   
962.
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963.
BACKGROUND: Recombinant soluble forms of complement regulatory molecules, including the human complement regulatory protein CD46 (rsCD46), have been shown to inhibit hyperacute transplant rejection (HAR) and protect against complement-mediated inflammatory tissue damage. Similarly, recombinant soluble forms of the immunoglobulin receptor FcgammaRII (rsFcgammaRII) can attenuate antibody-mediated inflammatory responses. We have produced and tested the function of novel recombinant chimeric proteins that incorporate the functional domains of both CD46 (membrane cofactor protein, MCP) and the low affinity human IgG receptor FcgammaRII (CD32). METHODS: Two recombinant soluble chimeric proteins (CD46:FcR and FcR:CD46) were designed and produced using a human cell expression system. Their ability to protect cells against complement-mediated lysis (through the CD46 domain) and bind human IgG (through the Fc receptor domain) was assessed in vitro. They were also tested in vivo in the rat reverse passive Arthus reaction and a murine model of hyperacute cardiac transplant rejection. RESULTS: In vitro, the functional domains of the chimeric proteins each retained their activity. In vivo, the serum half-life of the recombinant chimeric proteins in mice was more than either rsCD46 or rsFcgammaRII. In the rat reverse passive Arthus reaction, intradermal injection of each recombinant protein substantially reduced inflammatory skin edema (>50%) and polymorphonuclear neutrophil infiltration (>90%). In the hyperacute rejection model, i.v. treatment with FcR:CD46 prevented complement-mediated rejection, macroscopic bruising, edema, and thrombosis more effectively than rsCD46. CONCLUSIONS: CD46/FcgammaRII bifunctional proteins have an improved ability to control complement-mediated hyperacute graft rejection and have therapeutic potential in other conditions involving antibody-mediated inflammation.  相似文献   
964.
目的:介绍胃粘膜瓣成型预防食管胃吻合术后反流的临床应用.方法:食管、贲门癌50例,行部分食管部分胃切除,用吻合器作食管胃吻合后行胃粘膜瓣成型.结果:成型组术后无反流症状,上消化道造影及放射性核素显像表明该手术方法抗反流作用明显.食管镜检查示胃粘膜瓣成型组吻合口粘膜充血、水肿、糜烂、溃疡较常规手术组明显减轻.结论:胃粘膜瓣成型术可有效预防食管胃吻合术后胃食管反流.  相似文献   
965.
PURPOSE: To evaluate the potential of the new prognostic information gained by analyzing the coexpression of epidermal growth factor receptor (EGFR) and cyclooxygenase-2 (COX-2) in cervical cancer patients. EXPERIMENTAL DESIGN: Sixty-eight patients with International Federation of Gynecology and Obstetrics stage IIB squamous cell carcinoma of the uterine cervix, who underwent concurrent chemoradiotherapy between 1993 and 1996, were divided into the following four groups according to their immunoreactivities for EGFR and COX-2 in paraffin-embedded sections: (a). the EGFR-negative/COX-2-negative group (n = 11); (b). the EGFR-negative/COX-2-positive group (n = 8); (c). the EGFR-positive/COX-2-negative group (n = 27); and (d). the EGFR-positive/COX-2-positive group (n = 22). The clinical features, patterns of treatment failure, and survival data in the four groups were compared. RESULTS: Positive immunoreactivity for EGFR and COX-2 was observed in 49 of 68 (72%) and 19 of 68 (28%), respectively. However, no strong correlation was found between the levels of EGFR and COX-2 immunopositivity (R(2) = 0.05, P = 0.07). Patients in the EGFR-positive/COX-2-positive group had a higher likelihood of locoregional recurrence than those in the other three groups (P = 0.02). Of the patients in the four groups, patients positive for both oncoproteins were found to have the worst prognosis with an overall 5-year disease-free survival rate of 55% compared with 91% for the EGFR-negative/COX-2-negative patients, 88% for the EGFR-negative/COX-2-positive patients, and 69% for the EGFR-positive/COX-2-negative patients (P = 0.05, log-rank test). In addition, the synchronous coexpression of the EGFR and COX-2 oncoproteins was found to be an independent prognostic factor by univariate and multivariate analyses (relative risk = 4.0, P = 0.03). CONCLUSIONS: Given these observations, we conclude that the coexpression of EGFR and COX-2 immunoreactivity may be used as a potent molecular risk factor for predicting the poor survival of patients with the International Federation of Gynecology and Obstetrics stage IIB squamous cell carcinoma of the uterine cervix.  相似文献   
966.
PURPOSE: Docetaxel, a taxane previously approved for the treatment of breast cancer and non-small cell lung cancer, was approved by the United States Food and Drug Administration on May 19, 2004 for use in combination with prednisone for the treatment of metastatic androgen-independent (hormone-refractory) prostate cancer. The purpose of this summary is to review the database supporting this approval. EXPERIMENTAL DESIGN: In a randomized, global study enrolling 1,006 patients, two schedules of docetaxel were compared with mitoxantrone + prednisone as follows: MTZ q 3w, mitoxantrone 12 mg/m2 every 21 days + prednisone 5 mg twice a day for a total of 10 cycles; TXT q 3w, docetaxel 75 mg/m2 every 21 days + prednisone 5 mg twice a day for a total of 10 cycles; and TXT qw, docetaxel 30 mg/m2 days 1, 8, 15, 22, and 29 every 6 weeks + prednisone 5 mg twice a day for a total of 5 cycles. RESULTS: There was a statistically significant overall survival advantage shown for the TXT q 3w arm over MTZ q 3w (median survival 18.9 months versus 16.5 months, P = 0.0094). No overall survival advantage was shown for TXT qw compared with MTZ q 3w. The most commonly occurring adverse events included anemia, neutropenia, infection, nausea, sensory neuropathy, fluid retention, alopecia, nail changes, diarrhea, and fatigue. CONCLUSIONS: This report describes the Food and Drug Administration review supporting this first approval of a combination therapy for hormone-refractory prostate cancer based on demonstration of a survival benefit.  相似文献   
967.
BACKGROUND: In nonprimates, organ allografts are often not rejected after withdrawal of immunosuppression. In this study, we examined whether such a phenomenon also occurs in primates. METHODS: Vervet monkeys were transplanted with renal allografts and treated for 60 days with tacrolimus, or tacrolimus plus sirolimus. The drugs were totally withdrawn on day 61. The survival of the monkeys was monitored, and their response to donor- or third party-derived alloantigens was examined in vivo and in vitro. RESULTS: The majority (80-100%) of the grafts survived for at least additional 30 days with no signs of acute rejection. The compromised rejection is donor-specific, because recipient monkeys failed to reject a donor-derived skin graft, but a third-party skin graft was rejected. In vitro mixed lymphocyte reaction and interleukin-2 production in the mixed lymphocyte reaction between the recipients and their donors or between the recipients and a third party had no discernable patterns, and thus did not reflect the in vivo status of the immune system. Although the recipients could not reject the graft acutely after drug withdrawal, the kidney grafts and the donor-derived skin grafts had pathological findings of chronic rejection. CONCLUSIONS: The rejection response of the monkeys to an established graft after withdrawal of immunosuppression is compromised. The compromised rejection is specific and is not due to a permanent alteration of the immune system by the initial drug treatment. The allografts are not inert but have low levels of interaction with the recipient immune system.  相似文献   
968.
969.
970.
Objective Discussion of diagnosis, treatment and prognosis of non-palpable TO breast cancer. Methods Between 1978 and 1997, 9,980 female patients with operable breast cancer were treated surgically, of which 276 were determined to have TO breast cancer. Most TO breast cancers could be detected promptly with careful examination of presenting symptoms, such as nipple discharge, local thickening of the breast, nipple erosion, nipple retraction and postmenopausal mastalgia, while 12 cases were detected by routine mammography of the contralateral breast. Results All patients were treated surgically and their tissue subjected to histopathological examination. Most cases (73.0%) were noninvasive or early invasive carcinoma. Axillary lymph nodes metastases were found in 7.69% of 234 mastectomy cases. Conclusion The survival rate was significantly increased if the tumor was in an early stage. The 5-, 10-, 15-years survival rates were 98.1%, 94.6% and 90.3%, respectively.  相似文献   
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