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271.
Background: Acetaldehyde is suspected of playing a critical role in cancer development in the upper aerodigestive tract (UADT). The high salivary acetaldehyde levels after alcohol drinking are partly due to acetaldehyde production by oral bacteria. Some alcoholic beverages, especially Calvados and shochu, contain very high levels of acetaldehyde. Inactive heterozygous aldehyde dehydrogenase‐2 (ALDH2) increases the risk of UADT cancer in drinkers. Methods: In a randomized cross‐over design study, 19 healthy Japanese volunteers ingested 0.6 g ethanol/kg body weight in the form of 13% ethanol Calvados, 13% ethanol shochu, 13% ethanol red wine, and 5% ethanol beer under the fasting conditions at 3‐week intervals. We monitored blood and salivary acetaldehyde concentrations immediately after drinking, and 30, 60, 90, 120, and 180 minutes after completion of drinking. Results: The acetaldehyde concentration of each beverage was: Calvados 0.60 mM (1.86 mM in 40% undiluted solution), shochu 0.60 mM (1.16 mM in 25% undiluted solution), red wine 0.25 mM, and beer 0.14 mM. The salivary acetaldehyde concentration immediately after drinking wine was significantly lower than the other beverages, and it was significantly lower immediately after drinking beer than Calvados. The acetaldehyde concentrations 30 to 180 minutes after drinking were unrelated to the beverage type. Throughout the observation period the salivary acetaldehyde concentrations were much higher than the blood acetaldehyde concentrations in all 12 active ALDH2 homozygotes (24 to 53 μM in saliva vs. 2 to 5 μM in blood) and in all 7 inactive ALDH2 heterozygotes (37 to 76 μM in saliva vs. 12 to 25 μM in blood), and they were 13 to 25 μM higher in the ALDH2 heterozygotes than in the ALDH2 homozygotes after adjusting for age, body weight, sex, smoking and drinking habits, and time since the last toothbrushing. The values after subtracting the blood acetaldehyde concentration from the salivary acetaldehyde concentration were also higher in the ALDH2 heterozygotes than in the ALDH2 homozygotes. Conclusions: There are differences in exposure of the UADT to high salivary acetaldehyde concentrations according to the type of alcoholic beverage and ALDH2 genotype, and the differences partly explain the differences in the cancer susceptibility of the UADT according to alcoholic beverage and ALDH2 genotype.  相似文献   
272.
Background: The effects of genetic polymorphism of aldehyde dehydrogenase‐2 (ALDH2) on alcohol metabolism are striking in nonalcoholics, and the effects of genetic polymorphism of alcohol dehydrogenase‐1B (ADH1B) are modest at most, whereas genetic polymorphisms of both strongly affect the susceptibility to alcoholism and upper aerodigestive tract (UADT) cancer of drinkers. Methods: We evaluated associations between ADH1B/ADH1C/ALDH2 genotypes and the blood and salivary ethanol and acetaldehyde levels of 168 Japanese alcoholic men who came to our hospital for the first time in the morning and had been drinking until the day before. Results: The ethanol levels in their blood and saliva were similar, but the acetaldehyde levels in their saliva were much higher than in their blood, probably because of acetaldehyde production by oral bacteria. Blood and salivary ethanol and acetaldehyde levels were both significantly higher in the subjects with the less active ADH1B*1/*1 genotype than in the ADH1B*2 carriers, but none of the levels differed according to ALDH2 genotype. Significant linkage disequilibrium was detected between the ADH1B and ADH1C genotypes, but ADH1C genotype did not affect the blood or salivary ethanol or acetaldehyde levels. High blood acetaldehyde levels were found even in the active ALDH2*1/*1 alcoholics, which were comparable with the levels of the inactive heterozygous ALDH2*1/*2 alcoholics with less active ADH1B*1/*1. The slope of the increase in blood acetaldehyde level as the blood ethanol level increased was significantly steeper in alcoholics with inactive heterozygous ALDH2*1/*2 plus ADH1B*2 allele than with any other genotype combinations, but the slopes of the increase in salivary acetaldehyde level as the salivary ethanol level increased did not differ between the groups of subjects with any combinations of ALDH2 and ADH1B genotypes. Conclusions: The ADH1B/ALDH2 genotype affected the blood and salivary ethanol and acetaldehyde levels of nonabstinent alcoholics in a different manner from nonalcoholics, and clear effects of ADH1B genotype and less clear effects of ALDH2 were observed in the alcoholics. Alterations in alcohol metabolism as a result of alcoholism may modify the gene effects, and these findings provide some clues in regard to associations between the genotypes and the risks of alcoholism and UADT cancer.  相似文献   
273.
AIM:To evaluate the association of Helicobacter pylori(H.pylori)-related chronic gastritis stage with upper gastro-intestinal symptoms and gastro-eso-phageal reflux disease(GERD).METHODS:Subjects underwent upper gastrointestinal endoscopy,a questionnaire using a frequency scale for symptoms of GERD(FSSG),and measurements of serum H.pylori-antibody and pepsinogen(PG)levels.They were classified into the following 4 groups in terms of H.pylori-related chronic gastritis stage:Group A(n = 219),H.pylori(-)PG(-);Group B(n = 310),H.pylori(+)PG(-);Group C(n = 279),H.pylori(+)PG(+);and Group D(n = 17),H.pylori(-)PG(+).RESULTS:Reflux esophagitis occurred in 30.6% of Group A,14.5% of Group B,6.8% of Group C,and 0% of Group D(P < 0.001).Scores for acid reflux sympto-ms decreased significantly with chro-nic gastritis stage(from Group A to D)(P < 0.05),while scores for dysmotility symptoms did no-t differ significantly.The prevalence of nonerosive reflux disease(NERD)did not differ amo-ng groups.However,in subjects with GERD,the prevalence of NERD tended to increase with chronic gastritis stage(P = 0.081).CONCLUSION:Acid reflux sympto-ms and the prevalen-ce of reflux esophagitis can be assessed by measuring both serum H.pylori-antibody and PG levels.  相似文献   
274.
Background. Inhaled corticosteroids are used for the treatment of bronchial asthma. Systemic side effects are rare, but local problems, such as oral candidiasis, can occur. Only a proportion of patients encounter this problem, and the mechanism of oral candidiasis induced by inhaled corticosteroids remains obscure. According to reports in immunodeficient patients, oral candidiasis is related to deficiencies in topical immunity, such as salivary IgA. Objectives. We evaluated differences in salivary IgA between asthmatics in whom Candida was detected or not detected from the pharynges, respectively. Methods. Saliva was collected from 18 healthy controls and 37 asthmatic patients treated with inhaled corticosteroids. The amounts of total IgA and the Candida-specific IgA of the saliva were measured. Fungal culture of the pharyngeal wall was also performed. Results. There were no differences in salivary total IgA and Candida-specific IgA between healthy controls and culture-negative asthmatic patients. Salivary total IgA of Candida-positive asthmatic patients was significantly lower than that of Candida-negative patients. However, there was no difference in Candida-specific IgA levels between these two groups. Conclusions. Our results suggest that inhaled corticosteroids can potentially decrease salivary total IgA but that host factors are also important in the development of oral candidiasis.  相似文献   
275.
The proposition that stress level is affected by self‐esteem development, for which acceptance from others in childhood is a key issue, was tested in two health care professions. The sample was 131 from nursing studies and 91 from pharmacy studies at a university in London, and 344 from nursing and 976 from pharmacy in Tokyo. Levels of stress were measured with the Perceived Stress Scale, self‐esteem with the Rosenberg Self‐Esteem Scale and childhood acceptance with the Parental Nurturance Scale. The data were analysed in terms of levels of and causal path between stress, self‐esteem and childhood acceptance. The proposed mechanism was supported among the nursing and pharmacy students in both British and Japanese cultures. The sample was also found to be substantially high on stress and low on self‐esteem and childhood acceptance. The results suggested that those entering the health care profession, such as nursing and pharmacy, have some additional vulnerability to stress compared with the general population. Enhancing self‐esteem was strongly recommended in stress management for health care professions. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
276.

Purpose  

Micropapillary adenocarcinoma is becoming increasingly recognized as a prognostically important histological subtype of carcinoma in various organs. This report presents the clinicopathological findings of lung adenocarcinomas with micropapillary components.  相似文献   
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