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1.
双波长紫外分光光度法测定贝母中腺苷和胸苷的含量   总被引:4,自引:0,他引:4  
将4种贝母的甲醇提取物经薄层色谱法粗分离后,直接用双波长紫外分光光度法测定其含量。结果表明,该方法线性关系好,腺苷和胸苷标准曲线的相关系数均为0.9999,同时也发现平贝、炉贝和伊贝中腺苷都占核苷总量60%以上,而浙贝中仅占约40%,提示贝母生药的抗凝血活性可能与贝母中核苷类化合物的种类和含量的差别有关。  相似文献   
2.
Delta hepatitis virus infection in China   总被引:1,自引:0,他引:1  
To assess the prevalence, epidemiological features and prognostic implications of hepatitis D (Delta) in Sichuan Province, The People's Republic of China, 649 sera (515 from HBsAg positive patients and 134 from HBsAg negative subjects) were tested by radioimmunoassay (RIA) for antibody to the hepatitis D virus (anti-HD). Forty-seven sera (7.2%) showed some degree of reactivity. Serial dilutions of these sera indicated that prozoning was not responsible for the equivocal results. Thirty-four of the 47 sera were submitted under code to a second laboratory for independent analysis. According to those results anti-HD antibodies were detected in four of these sera. The overall prevalence of anti-HD in the HBsAg positive patients therefore was 0.8% (4/515). On the basis of clinical, biochemical and histological data 427 HBsAg positive sera were further divided into acute Type B hepatitis, chronic Type B hepatitis, healthy carrier state and hepatocellular carcinoma (HCC) subgroups. Two of 65 (3.1%) anti-HD positive sera belonged to the acute Type B hepatitis group; one of 104 (0.9%), the chronic Type B hepatitis group and one of 246 (0.4%), the healthy carrier group. No antibody was detected in sera from 12 HBsAg positive HCC patients. All HBsAg negative patients were negative for anti-HD antibody. The results of this study indicate that despite a high prevalence of hepatitis B virus infection, positive serology for delta virus is uncommon in Sichuan Province, The People's Republic of China.  相似文献   
3.
R Gray  R Hills  R Stowe 《Annals of oncology》2003,14(9):1338-1339
This issue of Annals of Oncology sees a report of a trial bythe Italian INTACC intergroup comparing folinic acid-modulatedfluorouracil, combined with levamisole, with fluorouracil andlevamisole alone [1]. This large trial (n = 1703) adds importantlyto our knowledge of the value of folinic acid in the fluorouracil/folinicacid (FUFA) chemotherapy combination, which is now widely acceptedas the standard regimen in colorectal cancer [2]. No statisticallysignificant differences in terms of disease-free survival oroverall survival were found from modulating the action of fluorouracilwith folinic acid. However, the absence of a statistically significantdifference does not of course establish lack of benefit. Therewere fewer deaths (32%  相似文献   
4.
Background: Anesthetic preconditioning (APC) with sevoflurane reduces myocardial ischemia-reperfusion injury. The authors tested whether two brief exposures to sevoflurane would lead to a better preconditioning state than would a single longer exposure and whether dual exposure to a lower (L) concentration of sevoflurane would achieve an outcome similar to that associated with a single exposure to a higher (H) concentration.

Methods: Langendorff-prepared guinea pig hearts were exposed to 0.4 mm sevoflurane once for 15 min (H1-15; n = 8) or 0.4 mm (H2-5; n = 8) or 0.2 mm sevoflurane (L2-5; n = 8) twice for 5 min, with a 5-min washout period interspersed. Sevoflurane was then washed out for 20 min before 30 min of global no-flow ischemia and 120 min of reperfusion. Control hearts (n = 8) were not subjected to APC. Left ventricular pressure was measured isovolumetrically. Ventricular infarct size was determined by tetrazolium staining and cumulative planimetry. Values are expressed as mean +/- SD.

Results: The authors found a better functional return and a lesser percentage of infarction on reperfusion in H2-5 (28 +/- 9%) than in H1-15 (36 +/- 8%; P < 0.05), L2-5 (43 +/- 6%; P < 0.05), or control hearts (52 +/- 7%; P < 0.05).  相似文献   

5.
6.
The effectiveness of a single preinduction intravenous (IV) bolus of esmolol in blunting hemodynamic responses to rapid sequence induction and tracheal intubation was evaluated. In a randomized double-blind study, 32 ASA I and II healthy patients scheduled for surgery were monitored with electrocardiography (EKG) lead V5, arterial cannulation, and impedance cardiography. After preoxygenation and a priming dose of vecuronium (0.01 mg/kg), patients received either saline (n = 12), esmolol 100 mg (n = 10), or esmolol 200 mg (n = 10) as an IV bolus (20 ml volume). This procedure was immediately followed by a 5 ml IV saline flush, cricoid pressure, thiopental sodium 5 mg/kg, and succinylcholine 1.5 mg/kg. Patients receiving 200 mg of esmolol had a 50% reduction in the usual tachycardia associated with induction and a greater decline in systolic blood pressure (SP) (by 50%) prior to intubation as compared with the placebo group (p less than 0.05). The increase in diastolic blood pressure (DP) and the reduction in stroke volume (SV) produced by induction and intubation were similar in all the groups. Plasma norepinephrine levels at 1.5 minutes after intubation increased in the esmolol groups about 130% above that measured in the placebo group. This finding was associated with a more gradual return of peripheral resistance to baseline following tracheal intubation. However, both doses of esmolol effectively attenuated heart rate (HR), SP, and rate pressure product (RPP) increases (p less than 0.05 vs placebo) produced by laryngoscopy and tracheal intubation.  相似文献   
7.
Archives of Sexual Behavior - Although men who have sex with men (MSM) within rural communities are disproportionately impacted by HIV, limited HIV research and programmatic resources are directed...  相似文献   
8.
This paper reports the findings of an evaluation (funded by the Department of Health) of six Communication Aid Centres established in 1983. The evaluation was undertaken to assess the effectiveness of these Centres in meeting their set objectives, and to examine service costs and client satisfaction. The findings show that the work of each Centre was effective in meeting its stated objectives, but that the work of individual Centres reflected its own specialised interests. Two problems with current funding arrangements were highlighted. First, the need to replace the original funding by locally based finance, and second, the funding of communication aids for clients. The findings also show that the specialist service provided by these Centres can be managed at costs per person assessed at, or below, non-specialist services in health districts. Client satisfaction with the services provided by the Centres was high.  相似文献   
9.
10.
Paroxetine in human breast milk and nursing infants   总被引:4,自引:0,他引:4  
OBJECTIVE: The purpose of this study was to determine the extent of infant medication exposure through breast-feeding during maternal treatment with paroxetine. METHOD: Breast milk and paired maternal and infant sera were collected after 10 days of maternal treatment with paroxetine at a stable daily dose (10-50 mg/day). All samples were analyzed by means of high-performance liquid chromatography with ultraviolet detection and a limit of detection of 2 ng/ml. RESULTS: Breast milk paroxetine concentrations were highly variable (2-101 ng/ml) and were present in all breast milk samples (N=108). A significant gradient effect was observed, with greater paroxetine concentrations found in later portions of breast milk (hind milk) than in early portions (fore milk). No clear time course of paroxetine excretion into breast milk was demonstrated, although maternal paroxetine daily dose reliably predicted both trough and peak breast milk concentrations over a 24-hour period. In 16 mother and infant serum pairs, no detectable concentrations of paroxetine were found in the serum of the nursing infants. CONCLUSIONS: This study extends previous data by demonstrating the presence of paroxetine in the breast milk of nursing women treated with this medication. The low concentrations of paroxetine in infant serum and lack of any observable adverse effects after maternal use of this medication while breast-feeding parallels the available data on other selective serotonin reuptake inhibitors.  相似文献   
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