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31.
从人工液体发酵培养的蜜环菌[Armillaria mellea(Vahl.ex Fr.)Quel.]菌丝体的石油醚提取物中,经硅胶柱层析,低压柱层析和制备性薄层层析分离得到两个新的原伊鲁烷型倍半萜芳香酸酯类化合物。命名为蜜环菌辛素(armillarilin)和蜜环菌壬素(armillarinia),根据光谱(UV,IR,~1HNMR,~(13)CNMR和MS)分析,推定它们的化学结构分别为Ⅰ和Ⅱ。  相似文献   
32.
用Boc-和Tos-基团分别保护氨基和侧链胍基,以1%交联度聚苯乙烯二苯甲氨基树脂为载体,用DCC固相法合成肽,HF断裂肽树脂键和去除侧链保护基团,粗产物经高效液相层析纯化,合成了心肌兴奋肽Phe-Met-Arg-Phe-NH_2及其类似物Phe-Pro-Arg-Phe-NH_2,并观察了此二种肽对大鼠血压和心率的影响。  相似文献   
33.
Cervical cancer continues to be the most common cause of death among women in developing countries. Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MS) are critical enzymes of folate metabolic pathways. In this work, we have conducted a case–control study to assess the role of these two polymorphisms in cervical cancer development. We obtained blood samples from 200 women with cervical cancer and from equal matched controls and analysed using PCR-RFLP method. We found that the methylenetetrahydrofolate reductase variant CT and CT + TT genotypes decreased cervix cancer risk, statistically significant (OR:0.30, 95% CI: 0.18–0.51, P < 0.001 for CT and OR:0.29, 95% CI: 0.18–0.49, P = 0.0000006 for CT + TT). Similarly in those patients who used oral contraceptive with variant CT genotype, there was statistically highly significant reduced risk of cervix cancer (OR:0.25, 95% CI: –0.12–0.49, P < 0.001) of methylenetetrahydrofolate reductase gene. For the methionine synthase, 2756 variant AG and AG + GG genotypes were similarly associated with highly significant reduced risk of cervix cancer (OR: 0.13, 95% CI: 0.07–0.26, P < 0.001 for AG, and OR: 0.15, 95% CI: 0.08–0.27, P < 0.001 for AG + GG) genotypes. In conclusion, our study suggested that methylenetetrahydrofolate reductase and methionine synthase polymorphisms might have protective effect on the risk of cervical cancer in the North Indian women.  相似文献   
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Diabetes is a chronic disease that is characterized by an increased blood glucose level due to insulin resistance. Type 2 diabetes is common in middle aged and old people. In this work, we present a technique to analyze dynamic foot pressures images and classify them into normal, diabetes type 2 with and without neuropathy classes. Plantar pressure images were obtained using the F-Scan (Tekscan, USA) in-shoe measurement system. We used Principal Component Analysis (PCA) and extracted the eigenvalues from different regions of the foot image. The features extracted from region 1 of the foot pressure image, which were found to be clinically significant, were fed into the Fuzzy classifier (Sugeno model) for automatic classification. Our results show that the proposed method is able to identify the unknown class with an accuracy of 93.7%, sensitivity of 100%, and specificity of 83.3%. Moreover, in this work, we have proposed an integrated index using the eigenvalues to differentiate the normal subjects from diabetes with and without neuropathy subjects using just one number. This index will help the clinicians in easy and objective daily screening, and it can also be used as an adjunct tool to cross check their diagnosis.  相似文献   
37.
The epidemiology of hyperuricaemia and gout in Taiwan aborigines   总被引:4,自引:1,他引:4  
To determine the prevalence of hyperuricaemia, gout and gout-related factors in Central Taiwan Atayal aborigines, 342 subjects over 18 yr old were interviewed and examined. A questionnaire was designed to screen for signs and symptoms of gout and gout-related risk factors. Serum uric acid, triglyceride and creatinine were measured in all subjects. The prevalence of hyperuricaemia was 41.4% and that of gout 11.7% in aborigines. The uric acid level was 7.9+/-1.7 mg/dl in males and 5.7+/-1.5 in females, and differed significantly under age 70 yr (P < 0.001). Significantly increased triglyceride, creatinine and alcoholism was found in gouty patients compared with non-gouty patients. In 40 cases with gout, 54% had tophi and 35% of their first- degree relatives had gout. The high prevalence of hyperuricaemia and gout in Taiwan Atayal aborigines, a significant family predisposition, increased creatinine level and alcoholism suggest multiple factors affecting the hyperuricaemia.   相似文献   
38.
Background: The purpose of the present study was to compare iissue harmonic imaging (THI) and conventional sonography in focal hepatic lesions. Methods: Fifty patients with focal hepatic lesions were enrolled for study. Conventional grayscale and THI was performed in all the patients and two sets of images of the lesions were recorded (one each for THI and conventional) and assessed for fluid–solid differentiation, detail and overall image quality. These images were compared with conventional sonographic images and graded better, same or worse as per the case. Lesions were confirmed by fine‐needle aspiration cytology (FNAC)/surgery/other modalities such as computed tomography (CT) or magnetic resonance imaging (MRI). Results: Out of 50 patients with focal hepatic lesions, 21 patients had metastatic lesions (two single; 19 multiple) five patients had hepatocellular carcinoma (HCC), five patients had hydatid cysts, nine had simple hepatic cyst whereas five patients had liver abscess, three had focal fatty infiltration; and lymphoma and hemangioma were seen in one patient each. The first observer ranked THI better than standard sonography in 40 patients (80%) for fluid–solid differentiation, in 38 (76%) for detail and in 39 (78%) for overall image quality. The second observer ranked THI better than standard sonography in 39 patients (78%) for fluid–solid differentiation, in 40 (80%) for detail and in 42 (84%) for overall image quality. Tissue harmonic imaging provided additional information in eight patients (16%) and resulted in treatment alteration in three patients (6%). Conclusion: Tissue harmonic imaging was significantly better than conventional sonography for fluid–solid differentiation, detail and total image quality in focal hepatic lesions, especially in obese patients and patients with poor acoustic window.  相似文献   
39.
Two children are reported in whom intestinal pseudo-obstruction was the initial manifestation of systemic sclerosis. Gastrointestinal symptoms and skin changes resolved or improved in both children following treatment with prednisone and penicillamine (case 1) or methotrexate (case 2), although radiological changes of the gastrointestinal tract persisted at 3 and 2 yr of follow-up, respectively.   相似文献   
40.
Heroin use and addiction pose serious risks and side effects due to overdose. Quantification of heroin in biological samples is challenging due to rapid deacetylation of heroin to its active metabolites. In this study, we report the quantification of metabolic degradation of heroin by-products in biological urine samples. The presence of the drug was monitored after oral administration of heroin at different time intervals. Various biophysical techniques, such as high performance liquid chromatography (HPLC) and mass spectrometry (MS) were used to evaluate the presence of the drug. A competitive fluorescence based immunoassay was developed with a limit of detection (LOD) up to 0.01 ng mL−1 and the IC50 value was 0.1 ng mL−1, while the dipstick assay shows a LOD up to 5 ng mL−1. Rapid detection of narcotic drugs was carried out for biological urine samples collected at various time points. Validation of the developed dipstick was carried out for the standard as well as the spiked urine samples by fluorescence based immunoassay (FIA), using anti-morphine antibodies. A strong correlation (R = 0.94) was obtained between the developed dipstick and FIA assay for biological urine samples collected at various time points. The developed immunochromatographic dipstick is highly sensitive, field applicable and cost effective, and can serve as a first choice for the monitoring of narcotic drugs in blood, urine and saliva in drug addicts and athletes.

Pathway of heroin degradation post oral administration in mice.  相似文献   
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