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51.
安宫牛黄丸中小檗碱的HPLC法测定   总被引:4,自引:0,他引:4  
本文报道用HPLC法测定黄连及含黄连中成药安宫牛黄丸中小檗碱型生物碱。实验结果表明选用硅胶柱为固定相,以醋酸乙酯—甲酸—乙醇(15:3:2)为流动相,能使样品中四种小檗碱型的生物碱获得最佳分离。用此法测得不同厂家生产的安宫牛黄丸中盐酸小檗碱的含量为0.331~0.456%,平均回收率为97.23%,变异系数为1.2%。  相似文献   
52.
Carcinoembryonic antigen and carcinoids of the gastrointestinal tract   总被引:1,自引:0,他引:1  
We studied the prognostic significance of immunohistochemically localized carcinoembryonic antigen in 131 nonmetastasizing and 35 metastasizing gastrointestinal carcinoid tumors. The rate of positivity was lower with preabsorbed versus nonabsorbed polyclonal antiserum. Compared with generally used prognostic features (depth of invasion, tumor size, and mitotic rate) positivity for absorbed anticarcinoembryonic antigen was the most specific feature for metastatic tumors but was least sensitive. Although our results demonstrate that anticarcinoembryonic antigen, particularly when absorbed, is highly associated with metastatic disease, depth of invasion and tumor size are better predictors of behavior.  相似文献   
53.
The recent Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC) reiterated long-standing recommendations that Stage 1 hypertension (BP ≥ 140/90 mm Hg) without comorbidity should be treated initially with diuretics (DI) or beta blockers (BB). Yet market research suggests that many physicians prefer to use other drug classes, such as calcium channel blockers and ACE inhibitors.
OBJECTIVES: To explore the determinants of therapeutic choice in hypertension.
METHODS: We surveyed by mail a stratified random sample of 10,000 U.S. cardiologists, internists, and family/general practitioners. Physicians were queried about their practice environment and their knowledge, attitudes, and practices regarding antihypertensive therapy, including their choice of drugs to treat patients with specified clinical profiles. The probability that physicians would follow JNC guidelines Stage 1 hypertension was analyzed using multiple logistic regression with stepwise backward elimination to select variable with p < 0.001.
RESULTS: Completed surveys were received from 1,023 physicians. 86.7% prescribe drug therapy for Stage 1 hypertension, and 19.5% (22.5% of drug prescribers) limit their choices to DI and BB. Guideline conformity was higher among physicians who: practice in academic medical centrers; are older; are general practitioners (versus general internists); have smaller caseloads; have fewer hypertensive patients; have higher proportions of HMO, Medicaid, and uninsured patients; and experience more formulary restrictions. Cardiologists and family practitioners were less likely than internists to follow guidelines.
CONCLUSION: JNC guidelines are better accepted by academic physicians, older physicians who have more expenence using DI and BB, physicians with smaller caseloads and hence more time for follow-up and therapy adjustment, and physicians who face drug reimbursement constraints.  相似文献   
54.
INTERINNOMINO-ABDOMINAL AMPUTATION: CASE REPORT   总被引:1,自引:1,他引:0  
  相似文献   
55.
In a prospective study of 65 patients with bile duct obstruction, various radiologic modalities were compared for their capability to demonstrate the level and cause of obstruction and to indicate accurately tumor resectability. Ultrasound (US) was performed in 65 patients, computed tomography (CT) in 51, direct cholangiography (DC) in 57, and angiography in 35. The level of obstruction was correctly indicated by US in 95% of patients and by CT in 90%, and the cause was correctly indicated by US in 88%, by CT in 63%, and by DC in 89%. In predicting tumor resectability, US was correct in 71% of patients, compared with 42% for CT, 58% for DC, and 25% for angiography. US therefore appears to be the single most useful modality in the evaluation bile duct obstruction.  相似文献   
56.
从秋季采收的菊科植物大丁草Gerbera anandria(L.)Sch Bip.全草中共分出十三种成分。本文报道其中三个新化合物的结构鉴定.它们分别是3,8-dihydroxy-4-methoxy-coumarin(ⅪⅩ),3,8-dihydroxy-4-methoxy-2-oxo-2 H-1-benzopyran-5-carboxylic acid(ⅩⅦ),和5,8-dihydroxy-7-(4-hydroxy-5-methyl-coumarin-3-)-coumarin(ⅩⅪ)。  相似文献   
57.
目的:观察橄榄叶提取物对白陶土及鹿角菜胶诱导的大鼠骨关节炎组织炎症的预防作用及对关节软骨的修复作用。方法:试验于2005-11/12在大连医科大学中日合作医药科学研究所进行。实验动物:选择健康雄性SD大鼠80只。实验材料:受试物橄榄叶提取物[由日本国Eisai食品与化学有限公司(日本国东京市)提供]。实验分组及给药:按体质量将大鼠随机分为5组,每组16只。模型对照组,灌胃给予蒸馏水,消炎痛组,灌胃给予消炎痛2mg/kg体质量,其余3组为橄榄叶提取物组,分别给予橄榄叶提取物(活性成分为以羟基酪醇为主的多酚)25,50,100mg/kg体质量灌胃,连续5d。第1天给药后1h,采用白陶土与鹿角菜胶诱发大鼠单发亚急性关节炎。实验评估:①诱发关节炎后1,3,5d,用容积测量法测定每组8只大鼠的左右后肢足跖体积,计算肿胀度,并同时用游标卡尺测定其胫跗骨关节最大径。②诱发关节炎后第5天,测定大鼠足跖伊文思蓝含量。每组的另8只大鼠,在诱发关节炎第5天麻醉后处死,剪下右足跖做组织病理学检查,观察橄榄叶提取物对大鼠骨关节炎中组织炎症的预防作用及对关节软骨的修复作用。结果:80只大鼠全部进入结果分析。①足跖肿胀度及胫跗骨关节径:诱发关节炎后1,3,5d,橄榄叶提取物50mg/kg组和100mg/kg组大鼠的右后足跖肿胀度均明显小于模型对照组大鼠[1d:(46.7±4.2)%,(44.8±6.8)%,(52.5±4.0)%;3d:(40.4±4.8)%,(37.4±5.7)%,(45.0±2.9)%;5d:(34.5±4.8),(31.7±5.3)%,(40.4±4.0)%,P<0.05],橄榄叶提取物25mg/kg体质量组,50mg/kg体质量组,100mg/kg体质量组大鼠的右后胫跗骨关节径与模型对照组大鼠比较差异无显著性(P>0.05)。②足跖伊文思蓝含量:诱发关节炎后第5天,橄榄叶提取物50mg/kg,100mg/kg组大鼠的右后足跖伊文思蓝含量均明显小于模型对照组大鼠(P<0.05)。③组织病理学检查及评分:组织病理学检查可见,与模型对照组比较,橄榄叶提取物50mg/kg组,100mg/kg组大鼠骨关节炎中组织炎症浸润明显减少,软骨组织无破坏,且组织病理学评分也明显小于模型对照组(P<0.05)。结论:橄榄叶提取物在50mg/kg体质量及以上剂量能有效地预防白陶土与鹿角菜胶诱发的大鼠骨关节炎中组织炎症,且对软骨有修复作用。  相似文献   
58.
目的:为评价三维超声心动图在心血管疾病中的应用前景,验证左室心肌质量对心血管事件和死亡发生的预测价值,应用三维超声心动图检测左室心肌质量,探讨左室心肌质量与心血管病患者远期预后的关系。方法:①超声测定:选择2003-10/2007-04武警医学院附属医院CCU及普通病房住院的64例患者接受左室心肌质量指数、静息左室射血分数测定和NYHA心脏功能分级的评估,仪器采用彩色多普勒超声诊断仪,型号为GE vivid-7。②分组及随访:根据左室肥厚标准和各参数平均数分为2组,左室心肌质量指数男性<131g/m2或女性<100g/m2为Ⅰ组,男性≥131g/m2或女性≥100g/m2为Ⅱ组,连续随访54个月,观察终点为心源性死亡。结果:61例进入结果分析。随访期末发现左室心肌质量指数与远期死亡有着显著的相关性(r=0.592,P=0.000);静息左室射血分数和NYHA心脏功能分级与死亡没有相关性(P>0.05);左室肥厚的Ⅱ组死亡例数多于Ⅰ组(P<0.01),两组的静息左室射血分数和NYHA心脏功能分级比较差异不显著(P>0.05);左室心肌质量指数高于平均数的Ⅱ组与Ⅰ组死亡相对危险比为2.56(95%CI),差异有统计学意义(P=0.020),但是静息左室射血分数和NYHA心脏功能分级之间死亡相对危险比没有统计学意义(P>0.05)。结论:①左室心肌质量与心血管病患者远期预后关系密切,可用于预测心源性死亡的发生情况。②三维超声心动图测定左室心肌质量及功能参数方便准确,可用于心功能定量评估。  相似文献   
59.

Background

Management of high-grade T1 (formerly T1G3) bladder cancer continues to be controversial. Should patients with T1G3 bladder cancer have an immediate radical cystectomy or should they receive intravesical bacillus Calmette-Guérin preserving bladder? Gemcitabine and cisplatin (GC) adjuvant chemotherapy may help to strike a balance between intravesical and early cystectomy. For purposes of this study, we continue to refer high-grade T1 lesion as “T1G3.”

Objective

To evaluate the characteristics and the long-term outcome of GC adjuvant chemotherapy in T1G3 bladder cancer after transurethral resection of bladder tumor (TURBT).

Materials and methods

We, retrospectively, reviewed 48 patients who were newly diagnosed with T1G3 bladder cancer between January 2009 and December 2012. A total of 48 patients received 4 cycles of GC adjuvant chemotherapy after TURBT. One month after 4 cycles of GC adjuvant chemotherapy, response was evaluated by re-TURBT. Median follow-up was 59.5 (range: 18–70) months, all patients have been observed for more than 3 years. Salvage cystectomy was recommended for patients with persistent disease and for tumor progression after initial complete response.

Result

Complete response was achieved in 44 (91.7%) patients. Of complete responders, 5 patients experienced recurrence and 5 patients showed progression. The progression rate and disease-specific survival rate were 10.4% and 91.7% at 3 years, respectively. More than 80% of survivors preserved their bladder. Kaplan-Meier curves showed that concomitant carcinoma in situ (CIS) was the only factor that had an influence on progression-free survival (P = 0.022) and disease-specific survival (P = 0.017). Concomitant CIS was the prognostic factor for progression rate and disease-specific survival rate at 3 years (P = 0.008 and P = 0.035).

Conclusion

GC adjuvant chemotherapy is a safe conservative treatment for T1G3 bladder cancer, but effective is really a phase II study. Patients with T1G3 bladder cancer with concomitant CIS should be treated more aggressively because of the high risk of progression.  相似文献   
60.
BACKGROUND: Testing for antibody to hepatitis B core antigen (anti-HBc) as a surrogate for hepatitis C viremia is no longer needed for blood donor screening. Currently, the important question is how much its use supplements hepatitis B surface antigen (HBsAg) donor screening in preventing transfusion-transmitted hepatitis B virus (HBV) infection. STUDY DESIGN AND METHODS: In a study conducted in the 1970s, 64 blood donors were associated with 15 cases of HBV (1.0%) in 1533 transfusion recipients. Sera from 61 donors at donation and 29 follow-up visits were available for present-day assays for HBsAg, HBV DNA, anti-HBc, and antibody to HBsAg (anti-HBs). RESULTS: HBsAg was found in four previously negative blood donors; HBV DNA was limited to three of these four. Anti-HBc was detected in six HBsAg-negative donors. Two other donors were negative in all assays at donation, but positive for anti- HBc and anti-HBs 2 to 4 months later. The remaining donors were negative for all HBV markers, which left five recipient cases unexplained. No HBV transmission was observed when anti-HBs sample-to- negative control values were > or = 10. CONCLUSION: Some 33 to 50 percent of cases of hepatitis B that could be transmitted by transfusion of blood from HBsAg-negative donors are prevented by anti- HBc screening. Anti-HBc-positive donors unequivocally positive for anti- HBs should be considered noninfectious for HBV and should be allowed to donate. Anti-HBc screening of paid plasmapheresis donors, supplemented by anti-HBs testing, would reduce the amount of HBV to be processed by virus inactivation and increase the content of anti-HBs in plasma pools.  相似文献   
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