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991.
PEMMARAJU NARASIMHA RAO JAMES E. BURDETT JAMES W. CESSAC CECIL M. DiNUNNO DOROTHY M. PETERSON HYUN K. KIM 《Chemical biology & drug design》1987,29(1):118-125
The DL-arylamino acid ethyl ester derivatives of β-(3-pyridyl)-DL-alanine, and β-(3-benzo[b]thienyl)-DL-alanine were synthesized by diethyl acetamidomalonate condensation with the respective arylmethyl halides followed by partial hydrolysis to the monoethyl ester and decarboxylation. Each derivative was enzymatically resolved to a separable mixture of the corresponding N-acetyl-L-amino acid and the unchanged D amino acid derivative. Acidic hydrolysis of the latter gave the corresponding D-amino acid, the optical purity of which was established by HPLC analysis of the 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate (GITC) derivative. The free D amino acids were converted to D-BOC derivatives by reaction with di-tert-butyldicarbonate in tert-butyl alcohol, water and sodium hydroxide. 相似文献
992.
重症肌无力患者泼尼松治疗前后免疫学指标的变化 总被引:3,自引:0,他引:3
探讨泼尼松治疗重症肌无力(MG)免疫学机制。对382例MG患者在漏尼松中剂量冲击,小剂量维持疗法治疗前后,检测酰胆碱受体抗炎(AchRab),突触前膜抗体(PsMab),单个核细胞亚群(PBMC),肿瘤坏死因子(TNF),可溶性白介素-2受体(SIL-2R),β2-微球蛋白(β2-m),以及红细胞免疫功能的变化。结果表明:MG患者在泼尼松治疗前后多项免疫指标有显著性的变化。为泼尼松治疗MG提供了评定疗效的免疫学指标,进一步阐明了MG发病的免疫学机制。 相似文献
993.
Objective:This sudy was designed to observe somatostatin receptor subtype 2 (SSTR2) Mrna expression, and investigate the correlations between SSTR2 Mrna expression and steroid receptors in benign and malignant lesions of the breast. Methods: A total of 23 breast carcinomas,16 mammary hyperplasia and 9 mammary adenofibroma samples were analysed. The SSTR2 Mrna expression was examined by in situ hybridization using multiphase oligoprobes.The ER and PR were detected by immunohistochemical staining. A computerized image analysis system was utilized to estimate the relative contents of SSTR2 Mrna. Results: The positive rates of expression (87.0%) and relative contents (0.47) of SSTR2 Mrna in breast cancer were higher than those in benign breast lesions(64%,0.26) respectively( P<0.05). SSTR2 Mrna expression was closely correlated with ER and PR in breast cancer( P<0. 05), A positive correlation between SSTR2 Mrna expression and ER was also found in benign breast lesions. Conclusions: SSTR2 Mrna expressed both in benign and in malignant breast lesions, but higher in malignant than in benign ones. There was a significant positive correlation of SSTR2 Mrna expression with ER or PR. The results suggest that conbined treatment with an antiestrogen and a somatostatin analogue for ER-positive breast cancer is feasible. 相似文献
994.
Kenji Yoshimi Masatoshi Takeda Tsuyoshi Nishimura Takashi Kudo Yu Nakamura Kunitoshi Tada Nobuyoshi Iwata 《Brain research》1991,560(1-2):149-158
Changes in MAP2 and clathrin immunoreactivity were studied in gerbil hippocampus after transient cerebral ischemia. MAP2 immuno-reactivity decreased significantly by 1 h in the subiculum-CA1 and CA2 areas which correspond to reactive change, while no decrease was observed in CA1 until day 4. Before the initiation of delayed neuronal death, MAP2 immunoreactivity was not changed in CA1. On the other hand clathrin immunoreactivity increased in the pyramidal cell layer of CA1 by 3 h after ischemia and remained high for 2 days. Clathrin immunoreactivity in the pyramidal cell layer of CA1 diminished after delayed neuronal death. The transient change of clathrin was noted especially in CA1 in the period prior to delayed neuronal death. These results imply an abnormal change in clathrin turnover after ischemia, which may participate in the pathogenesis of delayed neuronal death. 相似文献
995.
胆汁胆固醇对胆囊收缩素受体表达的影响 总被引:2,自引:0,他引:2
目的:探讨胆汁胆固醇对胆囊收缩素受体(CCK-R)表达的影响。方法 采用放射免疫分析法和受体放射配基结合法检测对照组、高胆固醇组、自然恢复组及治疗组豚鼠门静脉血CCK水平、胆囊CCK-R的最大结合容量(Bmax)和亲和力(Kd),同时观察空腹胆囊体积(FV)、胆囊胆汁量(FB)和餐后胆囊体积(RV)、胆囊胆汁量(RB)及胆囊收缩率(E%)、胆汁胆固醇浓度的变化。结果 与对照组比较,高胆固醇组豚鼠FV、FB增大(P<0.05),RV、RB也增大,胆囊收缩率下降(P<0.01),胆汁胆固醇浓度升高(P<0.05),门静脉血CCK水平及CCK-R的Kd无改变,而CCK-R的Bmax下降(P<0.01);治疗组上述各项指标正常。结论 胆汁中的高胆固醇通过下调胆囊CCK-R表达而导致胆囊收缩功能障碍,降低胆汁高胆固醇浓度可以促进胆囊动力功能的恢复。 相似文献
996.
SHIGEKI OCHI MORIKAZU ONJI KAZUHITO SHIRAISHI KYOKO OHTU TOMOHIRO AKAO YOSHITO YANO NOBUYUKI TAKEI HIKARU MATSUI YASUYUKI OHTA MASAKICHI UMEDA 《Journal of gastroenterology and hepatology》1991,6(6):599-602
To clarify the prevalence of concurrent infection with hepatitis C virus (HCV), hepatitis B virus (HBV) and human T cell leukaemia virus (HTLV), we measured HCV antibody in the population of a district endemic for HBV and HTLV infection. Blood samples were collected in June 1990 from 579 inhabitants of four islands of Uwa Bay in the southwest of Ehime Prefecture in Japan. Anti-HCV antibody against C100-3 protein was detected using an enzyme-linked immunosorbent assay kit (Ortho Diagnostics). Thirteen of the 579 inhabitants (2.2%) were positive for anti-HCV, and this prevalence rate was not significantly different from the frequency of anti-HCV in Tokyo blood donors. A total of 11% (64 of 579) of the subjects were positive for HBsAg and 3.3% (19 of 579) were positive for anti-HTLV. These frequencies of HBsAg and anti-HTLV positivity were distinctly higher than the respective means of Japanese. All anti-HCV positive individuals were negative for HBsAg and anti-HTLV, while 54% (7 of 13) had increased alanine aminotransferase levels. These data suggest that the prevalence of HCV infection is not high even in an area endemic for HBV and HTLV infection. 相似文献
997.
用DNA重组技术构建CT-B表达性质粒pXB1及进一步修饰的pXB2,使CT-B基因在大肠杆菌中得到较高水平的表达(280~350ng/ml),且有71.5%分泌率。表达动力学研究阐明,克隆子培养24h产物收率较高。一定浓度的Mg~(2+)、L-组氨酸和天冬酰胺能刺激CT-B的表达。GM1-ELISA、CHO细胞测毒结合间接免疫荧光检测和家兔肠段结扎试验证实,表达的CT-B能与游离的或活细胞膜上的GM1受体结合,但无细胞和肠段毒性。这种细胞测毒结合免疫荧光序贯试验,为客观证实CT-B的生物学活性开拓了新途径。 相似文献
998.
Nobuo Takeichi Hisao Ito Rumi Haruta Toshiya Matsuyama Kiyohiko Dohi Eiichi Eiichi 《Cancer science》1991,82(1):19-22
The relationship between the histological grade of dedifferentiation of thyroid cancer and estrogen receptors (ER) was examined immunohistochemically. Thyroid cancers were from postmenopausal females of almost the same mean age (69-73 years old) and within the same period of time (1974–1983). ER immunoreactivity located in the nucleus of the epithelium was found in all 6 well differentiated papillary cancers, and 5 of them (83.3%) showed ER-immunoreactive (ER-IR) cells amounting to 20 or more per visual field (x 100) under a light microscope. Of the 6 cases of poorly differentiated papillary cancer, 5 (83.3%) had 1-19 ER-IR cells per visual field. ER-IR cells were negative in 5 out of 6 cases (83.3%) of anaplastic cancers. Thus, the number of ER-IR cells tended to decrease with the degree of atypism of thyroid cancer (P < 0.001). 相似文献
999.
Dual blockade of the renin-angiotensin system in type 1 patients with diabetic nephropathy. 总被引:7,自引:0,他引:7
Peter Jacobsen Steen Andersen Kasper Rossing Birgitte V Hansen Hans-Henrik Parving 《Nephrology, dialysis, transplantation》2002,17(6):1019-1024
BACKGROUND: Albuminuria and hypertension are predictors of poor renal and cardiovascular outcome in patients with diabetes. Approximately 30% of type 1 patients with diabetic nephropathy (DN) have albuminuria >1 g/day, and blood pressure >135 and/or >85 mmHg despite antihypertensive therapy with recommended doses of ACE inhibitor (ACEI) and diuretics. We tested the effect of dual blockade of the renin-angiotensin system (RAS) in these patients. METHODS: We performed a randomised double blind crossover trial with 2 months treatment with Irbesartan 300 mg o.d. and placebo added on top of previous antihypertensive treatment. We included 21 type 1 patients with DN responding insufficiently to ACEI and diuretics, as defined above. At the end of each treatment period, albuminuria, 24-h blood pressure and glomerular filtration rate (GFR) were measured. RESULTS: Addition of 300 mg Irbesartan to the patients' usual antihypertensive therapy induced a mean reduction in albuminuria of 37% (95% CI 20-49, P<0.001); from 1574 mg/24 h (95% CI 1162-2132) to 996 mg/24 h (95% CI 699-1419), a reduction in 24-h blood pressure of 8 mmHg systolic (95% CI -2 to 18) and 5 mmHg diastolic (95% CI 1-9) (P=0.11 and 0.01, respectively) (from placebo, mean (SE) 146 (4)/80 (2) mmHg). GFR remained unchanged. Serum potassium increased (mean 4.3 to 4.6 mmol/l, P=0.02). Intervention to reduce serum potassium was needed in two patients with GFR <35 ml/min/1.73 m(2). Otherwise the dual blockade with Irbesartan was safe and well tolerated. CONCLUSIONS: Dual blockade of the RAS may offer additional renal and cardiovascular protection in type 1 patients with DN responding insufficiently to conventional antihypertensive therapy, including recommended doses of ACEI and diuretics. 相似文献
1000.
目的 :应用荧光定量PCR方法精确检测HBV -DNA的拷贝数 ,为临床判断病毒复制程度提供指标 ;对比分析荧光定量PCR方法和ELISA方法检测HBV -DNA的结果。方法 :用荧光定量PCR法检测 10 14例用ELISA法诊断为乙型肝炎病人的血清HBV -DNA拷贝数。结果 :10 14例病人中 ,病毒拷贝数≥ 1× 10 5的 4 99例 ,阳性率4 9.2 % ;HBeAg阳性患者的HBV -DNA拷贝数≥ 1× 10 5的阳性率显著高于HBeAg阴性患者。结论 :荧光定量PCR检测HBV病毒复制情况结果准确 ,对临床工作指导意义更大 ;HBeAg是一项重要指标。 相似文献