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41.
Alan T. Villavicencio MD Lloyd A. Hey MD Dhavalkumar Patel MD PhD Peter Bressler MD 《The Journal of allergy and clinical immunology》1997,100(6):853-854
J Allergy Clin Immunol 1997;100:853-4. 相似文献
42.
John S. Baer Daniel R. Kivlahan G. Alan Marlatt 《Alcoholism, clinical and experimental research》1995,19(1):54-58
Alcohol use and related problems were studied from the senior year in high school to the first autumn in college for 366 heavy drinking students. Four risk factors-subject sex, family history of drinking problems, prior conduct problems, and type of college residence-were evaluated as predictors of: (1) differential changes in drinking rates, (2) differential changes in alcohol-related problems, and (3) alcohol dependence symptoms during the first college term. Results suggest that both dispositional and environmental factors are associated with changes in drinking rates and the existence of dependence symptoms. Increases in the frequency of drinking were specifically and strongly associated with residence in a fraternity (men) or sorority (women). Three risk factors were associated with increased quantity of drinking: male gender, residence in a fraternity or sorority, and a history of conduct problems. Prior conduct problems were also consistently associated with dependence symptoms during the first term in college. A family history of alcohol problems was not consistently related to changes in use rates or problems, although some analyses suggest interactive effects. Early interventions on college campuses should target individuals using additive risk profiles. 相似文献
43.
We report a case of malakoplakia in association with colonic adenocarcinoma. Tumour-associated malakoplakia in the gastrointestinal tract is a rare finding, generally confined to the colon. It may be locally aggressive, with invasion of pericolic tissues, but is always located adjacent to the tumour. This contrasts with the often more diffuse, multifocal distribution of colonic malakoplakia in association with other pathologies. 相似文献
44.
45.
Septic or inflammatory stimuli suppress drug metabolism by cytochrome P-450 in the liver, presumably at the pretranslational level. We have shown previously that nitric oxide is responsible at least in part for the inhibition by bacterial lipopolysaccharide of phenobarbital-induced CYP2B1/2 activity in vivo. This was attributed to the interaction of nitric oxide with heme in the active-center of cytochrome P450, leading to enzyme inactivation. Here, we report of nitric oxide with heme in the active-center of cytochrome P450, leading to enzyme inactivation. Here, we report that endogeneous nitric oxide also contributes to LPS-induced suppression of CYP2B1/2 in vivo by down-regulating the expression of CYP2B1/2 protein and mRNA. 相似文献
46.
Smoking and raven IQ 总被引:1,自引:0,他引:1
Nicotine has recently been shown to enhance measures of information processing speed including the decision time (DT) component of simple and choice reaction time and the string length measure of evoked potential waveform complexity. Both (DT and string length) have been previously demonstrated to correlate with performance on standard intelligence tests (IQ). We therefore hypothesised that nicotine is acting to improve intellectual performance on the elementary information processing correlates of IQ. In the current experiment we tested this hypothesis using the Raven Advanced Progressive Matrices (APM) test. APM scores were significantly higher in the smoking session compared to the non-smoking session, suggesting that nicotine acts to enhance physiological processes underlying performance on intellectual tasks. 相似文献
47.
Thuy T. Chau Thomas Walter Alan Katz Barry M. Weichman 《Drug development research》1993,28(4):488-495
Pemedolac Na, 1-ethyl-1,3,4,9-tetrahydro-4-(phenylmethyl)-pyrano [3,4-b] indole-1-acetic acid sodium salt, exhibited equipotent analgesic effects after oral, iv, and im administration, suggesting that it is well absorbed. In mouse writhing models, the ED50 values ranged from 0.3 mg (0.81 μmol)/kg (vs. acetylcholine) to 4.3 mg (11.6 μmol)/kg (vs. paraphenylbenzoquinone [PBQ]). In the rat Randall-Selitto model, the ED50 o the compound was approximately 0.001 mg (2.7 nmol)/kg, with a flat dose response curve. The peak effects lasted for 7–9 h, 10–18 h, and 5 h following oral, im, and iv injections, respectively. Intracerebroventricular (i.c.v.) injections of pemedolac Na inhibited the PBQ-induced writing in mice with an ED50 of 43.5 μg (0.12 μmol)/mouse, and this effect was not antagonized by naloxone. It was inactive in the hot plate and tail flick tests, demonstrating that pemedolac Na does not act via an opiate mechanism. These results indicate that pemedolac Na is a viable parenteral and oral analgesic, typified by high analgesic potency, a rapid onset and long duration of action, and an extremely wide safety index. © Wiley-Liss, Inc. 相似文献
48.
A total of 580 breast milk samples were collected from 56 lactating women living in a rural village community in The Gambia, West Africa, and 92 samples were obtained from 57 lactating women living in Cambridge, England. Total zinc content of each sample was measured by atomic absorption spectrometry, and pooled samples of the Gambian breast milks, representing successive periods of lactation, were fractionated into fat, whey and insoluble casein fractions, to examine zinc distribution. The two sets of milks both exhibited a dramatic decline in total zinc concentrations with increasing duration of lactation, in common with previous studies. However, the UK milks unexpectedly had lower zinc contents at all stages than the Gambian milks. Milk zinc levels were not significantly related to either maternal age or parity in the Gambian women. The proportion of zinc found in the sedimentable fraction remained nearly constant with increasing duration of lactation, but the proportion found in the fat fraction increased and the proportion in the whey fraction declined. These observations are potentially relevant for estimations of milk zinc availability and the fulfillment of zinc requirements by infants, and hence for infant feeding practices. 相似文献
49.
Use of suture-mediated vascular closure devices for the management of femoral vein access after transcatheter procedures. 总被引:1,自引:0,他引:1
James A Shaw Elizabeth Dewire Alan Nugent Andrew C Eisenhauer 《Catheterization and cardiovascular interventions》2004,63(4):439-443
Groin complications remain the most common complication of cardiac catheterization procedures. While the use of closure devices is increasing for arterial sheaths, venous sheaths tend to be removed and hemostasis achieved with manual compression. We report our experience using Perclose suture-mediated vascular closure device to achieve hemostasis and early mobility in patients who have had venous access as part of their procedure. There were a total of 42 patients (21 males; average age, 63.5 years) studied. The majority of the patients had 7 Fr sheaths (24), with access sites of sheaths up to 14 Fr being closed with this technique. Two patients developed complications at the access site: one patient requiring rehospitalization for intravenous antibiotics because of late access site infection, and one patient with deep venous thrombosis and pulmonary emboli. We conclude that the use of the Perclose suture-mediated closure device for closure of femoral venous access sites is feasible and should be considered especially in patients with larger venous sheaths and those at increased risk of groin complications. 相似文献
50.
Melanie Inkster Alan Montgomery Peter Donnan Tom MacDonald Frank Sullivan Tom Fahey 《The British journal of general practice》2005,55(521):931-937
BACKGROUND: Studies show that 60-75% of treated patients with hypertension in general practice, still do not reach the recommended blood pressure targets of <150/90 mmHg. AIM: To investigate aspects of hypertension management in relation to sociodemographic variables, antihypertensive drug treatment, and organisational factors in primary care. DESIGN OF STUDY: Observational study over 3 years. SETTING: Eight general practices in Tayside, UK. METHOD: Participants were 560 randomly selected patients aged 40-79 years receiving treatment for hypertension. The outcome measurement was blood pressure control, expressed in binary form based on the British Hypertension Society audit standard of <150/90 mmHg. RESULTS: Of 536 eligible patients, 261 (49%) were defined as having inadequate blood pressure control at the end of the study period. No significant associations were discovered with sex, age, deprivation score and comorbidity. In those patients with inadequate control, 30% had no modifications to their drug treatment during the study period. Blood pressure control at the end of the study period was not associated with number of antihypertensive drugs taken or number of antihypertensive drug modifications. The mean number of clinician contacts was 11 (standard deviation = 8), and mean continuity in primary care was high, although this was not associated with improved blood pressure control. A higher proportion of hypertension-related consultations were associated with increased odds of having inadequate blood pressure control. CONCLUSION: Achieving adequate blood pressure control continues to represent a substantial health problem in a significant proportion of the hypertensive population. Patient, physician and organisational elements play a role in ensuring effective delivery of hypertension care in the community. 相似文献