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1.
可逆性胆硷酯酶抑制剂二甲氨基甲酸-5-二氢吲哚酯的合成   总被引:1,自引:0,他引:1  
陈邦华  纪庆娥 《药学学报》1990,25(4):247-252
为了深入研究催醒宁类化合物的结构与抑酶活性的关系,设计合成了-系列1-,3-或5-位不同取代的二氢吲哚类衍生物(中间体和终产物共24个新化合物)。中间体1,3-二甲基-5-烷氧基-2-二氢吲哚酮(A)的C3烷化。采用相转移催化方法进行;反应中还分离到三个副产物(Ⅶ~Ⅸ)。初筛结果表明:这些化合物大多有较强的抑酶活性;1,3-或5-位取代基的改变均明显影响其活性。  相似文献   
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Iridological constitution has a strong familial aggregation and is implicated in heredity. The aetiology of inflammatory bowel disease is still unknown. However, from genetic epidemiological studies there is considerable evidence that genetic factors are associated with both Crohn's disease and ulcerative colitis. We investigated the relationships between Iridological constitution and interleukin 1 beta (IL-1β) gene polymorphism. IL-1β is a major proinflammatiry cytokine, and the polymorphisms of this gene have been shown to be of importance in a number of diseases. Especially, IL-1 has been suspected of involvement in allergic pathogenesis. Also, IL-1β genotype is one of the genetic markers of gastric cancer. Therefore, we classified 166 individuals according to Iris constitution, and determined IL-1β genotype. The frequencies of Iris constitutions as follows: neurogenic type, 41 (24.7%); abdominal connective tissue weakness type, 53 (31.9%); cardio-renal connective tissue weakness type, 50 (30.1%); the others type, 22 (13.3%). Especially, the frequency of abdominal connective tissue weakness type was higher in C/T genotype than in the remaining constitutions although the statistical power was very weak. Furthermore, we first attempted to explore possible involvement of the IL-1β polymorphism and the Iris constitution.  相似文献   
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Previous studies have suggested that glutathione S-transferase (GST) genotypes may play a role in determining susceptibility to cervical cancer, though the data have often been conflicting. The objective of this study was to examine the effect of GSTP1 polymorphism on cervical carcinogenesis. The studied subjects, patients who were pathologically diagnosed with invasive cervical cancer yielding positive results for human papillomavirus (HPV) (n=342), were compared to healthy, normal, female controls (n=707). DNA from peripheral blood samples from studied subjects whose GSTP1 specific sequences had been determined by PCR with allele-specific primers were reviewed in comparison with the normal controls. The genetic susceptibility of GSTP1 (11q 13.1) in cervical carcinogenesis was determined by examining the effect of gene and environmental factors by the different histopathologic types of invasive cervical cancers. In assessing polymorphism GSTP1, the percentages of individuals homozygous for the A allele, homozygous for the G allele, and heterozygous for the two alleles were 66.8%, 3.9%, and 29.3%, respectively, in the control group, and 64.3%, 4.1%, and 31.6%, respectively, among in women with cervical cancer. Compared with GSTP1 G allele positive (GA or G/G), the odds ratio (OR) (95% confidence interval) for GSTP1 A/A was 1.0 (0.7 - 1.4) for invasive cervical cancer. However, the risk increased with GSTP1 A/A among ever smokers (3.9, 1.7 - 8.9, p-value=0.0012) compared with GSTP1 G allele positive among nonsmokers. In particular, this risk was higher among women with squamous cell carcinoma (4.7, 2.0 - 10.8, p=0.0003). Polymorphism of GSTP1 among smoking women was associated with a higher risk of developing cervical cancer.  相似文献   
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This study was designed to determine whether the somatostatin analogue, octreotide, could prevent embryonic loss by normalizing increased uterine insulin-like growth factor-I (IGF-I) action related to hyperoestrogenaemia following superovulation. Superovulated immature and oestradiol-17beta-treated adult rats were infused with 100 or 300 microg/ml of octreotide respectively, or injected daily with 1 or 10 microg of octreotide from day 1 to day 3 of pregnancy. On day 3, embryos were collected from the oviducts and uteri. Uterine luminal fluid was subjected to embryo culture. The amounts of uterine IGF-I and IGF binding proteins (IGFBP) were determined by radioimmunoassay and ligand binding assay respectively. Octreotide infusion normalized uterine IGF-I action following superovulatory and oestradiol-17beta treatment, by reducing IGF-I concentrations and increasing IGFBP concentrations. Octreotide infusion increased the number of normal embryos by 2.7-fold and 1.7-fold in superovulated and oestradiol-17beta- treated rats respectively, and reversed the detrimental effects of uterine luminal fluid on embryonic development caused by superovulatory and oestradiol-17beta treatment. Daily injections with octreotide had similar but reduced effects in all parameters examined in both treatment groups. In conclusion, octreotide may reduce embryonic loss, at least in part, by normalizing IGF-I action following superovulation.   相似文献   
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The applications of dental restorative composite resins containing 2,2 bis [4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane (Bis-GMA), as a base resin, and triethylene glycol dimethacrylate (TEGDMA), as a diluent, are often limited in dentistry due to the relatively large amount of volumetric shrinkage that occurs during the curing reaction. In this study, various new resin matrices were examined for use as dental composites in order to reduce the amount of volumetric shrinkage that occurs in dental composites as a result of curing. Bis-GMA derivatives were synthesized by substituting methyl groups for hydrogen on the phenyl ring. The derivatives of TEGDMA with different chain lengths or reactive groups were also examined. The molecular structural changes in the TEGDMA derivatives were not effective in reducing the level of volumetric shrinkage. The resin matrix containing a Bis-GMA derivative and TEGDMA showed a reduced amount of volumetric shrinkage in proportion to the number of methyl groups on the phenyl rings. Polymerization with a mixture of Bis-GMA, its derivatives and a diluent is a promising strategy for obtaining a polymer with a low amount of volumetric shrinkage. A comparison of the volumetric shrinkage of dental composites containing Bis-GMA, TMBis-GMA (2,2-bis[3,5-dimethyl, 4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane)), and TEGDMA with that prepared from a Bis-GMA and TEGDMA mixture showed that the volumetric shrinkage reduction in the new resin was approximately 50%. Furthermore, the mechanical strength of the former was higher than that of the latter.  相似文献   
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The purpose of this study was to prospectively examine the effectiveness and tolerability of a simple radiotherapy technique for the palliation of symptomatic liver metastases. Twenty‐eight patients with symptomatic liver metastases were enrolled from seven centres, and received targeted (partial or whole) liver irradiation consisting of 10 Gy in two fractions over 2 days. Symptoms at baseline were hepatic pain (27 patients), abdominal distension (19), night sweats (12), nausea (18) and vomiting (eight). Twenty‐two patients (76%) had failed previous treatment with chemotherapy, hormonal therapy and/or high‐dose steroids. Symptoms and potential toxicities were prospectively assessed at the time of treatment, then 2, 6 and 10 weeks later. Individual symptom response rates were 53?66% at 2 weeks. Partial or complete global symptomatic responses were noted in 15 patients (54%) overall. The treatment was well tolerated with two patients (7%) experiencing grade 3 toxicity (one vomiting and one diarrhoea); however, four patients reported temporary worsening of pain shortly after treatment. This simple and well‐tolerated treatment achieves useful palliation.  相似文献   
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Park JS, Kim CJ, Um SJ, Hwang ES, Kim HS, Park SN, Namkoong SE, Kim SJ. Immune response to p53 and HPV-16 E6 proteins in patients with cervical cancer. Int J Gynecol Cancer 1998; 8 : 328–335.
To investigate whether p53 autoantibodies could be found in the sera of patients with cervical cancers, we have therefore studied by radioimmunoprecipitation assay, using in vitro translated p53 protein, sera from such patients. The sero-positive patients for p53 were also evaluated in relation to immunoreactivity to p53 antigens by immunohistochemistry, for genomic alterations of p53 by PCR-SSCP, and for the presence of HPV-16/18 DNAs in the cervical cancer cells. In immunohistochemistry, expression of p53 protein was seen in 47% (14/30) of HPV-16 or -18 positive cervical cancers and 13 % (2/15) of HPV-16/18 negative cervical cancers ( P < 0.01). Eight out of 12 control ovarian cancers (67%) showed positive p53 staining in most tumor cells. Cases of cervical cancer and ovarian cancer, which were positively expressed p53 protein in the tissue or the sera, were studied for genomic alterations in exons 5–8 of the p53 by PCR-SSCP. Serum antibodies to in vitro translated p53 protein were found in two cases from 63 cervical cancers; one patient was stage IIA, having HPV-16 DNA in a tumor of squamous cell type, and another patient was stage IIIB, having HPV-16 and -18 DNAs in an adenocarcinoma. The cervical cancer tissues from the two sero-positive patients were also positive for p53 immunostaining. None of the cervical cancer samples showed aberrant bands, but three of eight cases of ovarian cancer which were positive for p53 protein by immunostaining were shown to have aberrant bands by PCR-SSCP. In contrast to ovarian cancers, alteration of p53 tumor suppressor gene and positive antibody response to p53 protein seem to be rare events in patients with cervical cancer.  相似文献   
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