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991.
在离子型培养基中分别添加6.804,13.610,27.216 g/L 的KH2PO4以及66.39,138.75, 277.4 mg /L 的CaCl2,对通风发酵过程中的不同K^+、Ca^2+浓度影响啤酒酵母代谢产6种有机酸含量的动态变化进行了跟踪检测.研究结果表明,K^+、Ca^2+可能通过作用于酵母细胞膜上的膜蛋白或调控生理代谢网络中代谢流相关的酶,从而使不同的K^+、Ca^2+浓度影响啤酒酵母响应产酸的峰值和峰值响应时间;在通风发酵过程中,啤酒酵母代谢产乳酸较多(多达8.3 mg/mL),产琥珀酸较少(不超过250 μg/mL);发酵终点时,随K^+、Ca^2+浓度增大,啤酒酵母代谢产酒石酸和琥珀酸等含量减少. 相似文献
992.
P. Botas E. Delgado G. Castaño C. Díaz de Greñu J. Prieto F. J. Díaz-Cadórniga 《Diabetic medicine》2003,20(11):904-908
AIMS: To estimate the prevalence of diabetes mellitus with three diagnostic criteria (WHO-1985 and 1999 and ADA-1997), evaluate their concordance and analyse the sensitivity and specificity of the different screening strategies for diabetes. METHODS: A cross-sectional population study with two-step sampling. One thousand and 34 people were selected randomly. A 75-g oral glucose tolerance test (OGTT) was performed and venous blood samples were obtained fasting and at 2 h. RESULTS: The prevalence of known Type 2 diabetes mellitus (DM-2) is 4%[95% confidence interval (CI) 2.8, 5.1]. By WHO-1985 criteria the prevalence of unknown DM-2 is 5.9% (4.5, 7.4); by ADA-1997 criteria 3.5% (2.5, 4.6) and by WHO-1999 criteria 7.3% (5.8, 8.8). Diagnostic overlap and statistical concordance (coefficient K) are WHO-1985/ADA-1997 29.3%, K=0.42; WHO-1985/WHO-1999 80%, K=0.88; ADA-1997/WHO-1999 48%, K=0.63. If only fasting glucose was used (following ADA-1997), 36.3% of those with diabetes (2-h glucose > or =11.1 mmol/l) would be diagnosed. If OGTT was performed (i) in those with a fasting glucose between 6.1 mmol/l and 6.9 mmol/l (9.8% of the population) we would diagnose 66.6%, and (ii) in all those between 5.7 mmol/l and 6.9 mmol/l (18.9% of the population) 81.8% would be diagnosed. CONCLUSIONS: The ADA criteria decrease the prevalence of DM in the adult population of Asturias by 2.4% and concordance with the classical criteria (WHO-1985) was only 29.3%. Using fasting glucose only (ADA-1997) diagnoses 36.3% of those with diabetes. The recent recommendations of the WHO-1999 increases this to 66.6%. To improve the diagnostic strategy for diabetes and detect up to 81.8% of patients, we propose the use of OGTT for all those with a fasting glucose between 5.7 mmol/l and 6.9 mmol/l. 相似文献
993.
YUKAKO ISHIHARA MASAHIRO SEIKE ITARU YOKOUCHI HIROAKI SUDA SHUNICHIRO ISHITSUKA TADAYOSHI KAKEMURA MITSUHIRO YOSHIDA KAZUYA YOSHIMOTO YOSHIHIRO SAKAI CHIDORI OKUMURA YOSHIHISA SAIDA 《Digestive endoscopy》2003,15(3):240-242
A 55‐year‐old‐man had a laparoscopic resection of the sigmoid colon due to colon cancer with submucosal invasion. After the surgery he suffered ileus and had a laparotomy. Six months later he complained of frequent defecation. Colonoscopy confirmed a circular ulcer extending from the anal side of the anastomosis in the sigmoid colon to the mid rectum. Endoscopic ultrasound demonstrated thickening of all layers of the diseased colon and rectum. We diagnosed ischemic colitis. After intravenous drip infusion of prostaglandin, symptoms and colonic stricture gradually improved. Although abdominal angiography revealed a narrowing of the peripheral sigmoid branch of the inferior mesenteric artery, blood flow was unrestricted. Colonoscopy performed 84 days after discharge revealed an ulcer scar. 相似文献
994.
A D Kriketos D G Carey A B Jenkins D J Chisholm S M Furler L V Campbell 《Diabetic medicine》2003,20(4):294-300
AIMS: To examine the relationships between body composition and changes in fasting glycaemia, and in indices of insulin secretion and insulin action over 6 years in females with a family history of Type 2 diabetes with or without prior gestational diabetes ('at risk' group, AR) and control females (control group, C). METHODS: At baseline and at follow-up, an oral glucose tolerance test and dual energy X-ray absorptiometry assessment of body composition were performed. Indices of insulin resistance (HOMA R') and insulin secretion (HOMA beta') were obtained from fasting insulin and glucose concentrations. RESULTS: At baseline, the groups were similar for age, body mass index, fasting levels of plasma glucose and insulin, HOMA R' and HOMA beta'. Despite similar total body fatness, AR had significantly greater waist circumference and central fat (both P < 0.02) compared with C. At follow-up there was a significant increase in central adiposity only in AR, and the fasting plasma glucose (FPG) level was higher in AR compared with C (5.0 +/- 0.2 vs. 4.3 +/- 0.2 mmol/l, P = 0.02). This rise in plasma glucose in AR was related to a decline in HOMA beta' (r = 0.45, P = 0.0065). Both the baseline and the increments in total and central abdominal fat mass were associated with the time-related decline in HOMA beta'. CONCLUSIONS: Six years after initial assessment, AR showed deterioration in FPG levels due predominantly to a decline in insulin secretion index without major change in insulin resistance index. Importantly, baseline body fatness (especially central adiposity), as well as increases in fatness with time, were the major predictors of the subsequent decline of insulin secretion index and the consequent rise in FPG. 相似文献
995.
儿童髓母细胞瘤中ERBB-2的表达 总被引:2,自引:1,他引:1
目的:探讨ERBB-2在儿童髓母细胞中的表达及临床意义.方法:用免疫组织化学LSAB法检测84例获随访的儿童髓母细胞瘤中的ERBB-2表达,按术后生存期3、5、10年分为A、B、C三组.使用Cox回归统计分析.结果:84例儿童髓母细胞瘤中,ERBB-2阳性表达72例(85.71%),A、B、C三组间ERBB-2阳性表达分别为100%,88.9%,40%(P<0.01),Cox回归分析显示ERBB-2是影响生存时间的一个独立的预后因子,它与预后存在负相关关系.结论:ERBB-2表达水平可作为儿童髓母细胞瘤的预后指标之一. 相似文献
996.
997.
杜仲对糖尿病大鼠扑捉行为和阴茎组织神经传导通路的影响 总被引:6,自引:1,他引:5
目的:探讨杜仲改善勃起功能的药效和病理学机制。方法:雄性糖尿病(DM)大鼠30只随机分为3组:A组(10只,DM大鼠赋形剂灌胃组)、B组(10只,DM大鼠西地那非灌胃组)、C组(10只,DM大鼠杜仲灌胃组)及10只正常对照组大鼠(赋形剂灌胃,D组);灌胃4周后观察4组大鼠扑捉行为,透射电镜检查阴茎组织有髓神经纤维超微特征;用免疫组化二步法显示阴茎组织中神经元型一氧化氮合酶(nNOS)的表达。结果:与A组比较,C组大鼠扑捉次数显著增多(P<0.05),阴茎组织中nNOS表达显著增强(P<0.001)。透射电镜显示:A组大鼠阴茎组织有髓神经纤维排布失序,部分变性、板层分离形成透明空泡或网络状,C组大鼠有髓神经纤维排列规整,板层结构清晰。结论:杜仲可通过减轻有髓神经的损伤、增强阴茎组织中nNOS表达改善ED。 相似文献
998.
999.
脑囊虫病患者血清和脑脊液IL-6和SIL-2R的水平及其与癫痫发作的关系 总被引:1,自引:0,他引:1
目的测定脑囊虫病患者血清和脑脊液IL-6和SIL-2R水平,并探讨其与癫痫发作的关系。方法应用双抗体夹心ELISA法测定45例脑囊虫病患者和43例对照组患者血清和脑脊液IL-6利SIL-2R的水平,其中脑囊虫病组又分为癫痫组(23例)和非癫痫组(22例),分别进行了比较分析。结果脑囊虫病组血清SIL-2R水平明显高于对照组(P<0.05);而IL-6水平与对照组比较无显著性差异(P>0.05)。脑囊虫病组脑脊液SIL-2R和IL-6水平均较对照组低(P<0.01,P<0.05);脑囊虫病组血清SIL-2R和IL-6水平与脑脊液SIL-2R和IL-6水平均呈正相关(r=0.322,P<0.05;r=0.768,P<0.01)。脑囊虫病癫痫组血清SIL-2R和IL-6水平与非癫痫组比较均无显著性差异(P>0.05);而脑脊液SIL-2R和IL-6水平癫痫组明显高于非癫痫组(P<0.01)。结论脑囊虫病患者外周血和中枢神经系统存在免疫激活,且SIL-2R和IL-6可能参与了癫痫发生过程。 相似文献
1000.
目的初步探讨血管生成素-2(Angiopoietin-2,Ang-2)在食管鳞状细胞癌组织中的表达及其与肿瘤病理分级、浸润和转移的关系。方法采用S-P免疫组织化学方法,对85例食管鳞癌及22例正常食管组织中的Ang-2表达水平进行检测,并与肿瘤病理分级、浸润深度及淋巴结转移情况进行统计学分析。结果85例食管鳞癌组织中,57例Ang-2表达呈阳性,阳性率为67.06%,显著高于Ang-2在正常食管组织中的表达(P<0.05)。Ang-2表达与肿瘤病理分级和淋巴结转移显著相关(P<0.05)。结论Ang-2的表达与食管鳞癌的临床分期及病理分级呈正相关,提示Ang-2促进肿瘤新生血管形成,参与食管鳞癌的发生和发展,可作为反映食管癌进展的生物学指标。 相似文献