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41.
Eight male habitual smokers smoked two cigarettes over a 20-min period following a 12-h period of abstinence. Antecubital venipuncture was performed immediately before, immediately after, and 55 min and 2 h after smoking had ceased. At these times, the mean values (+/- SD) of collagen-induced platelet aggregation were 45 +/- 5, 68 +/- 5, 59 +/- 6 and 52 +/- 5 chart units, respectively, while the corresponding values for the mean platelet aggregate ratio were 0.91 +/- 0.01, 0.82 +/- 0.03, 0.87 +/- 0.02 and 0.90 +/- 0.02, respectively. Mean collagen-induced platelet aggregation was significantly (P less than 0.005) higher immediately after, and 55 min and 2 h after smoking. The mean platelet aggregate ratio was significantly (P less than 0.001) lower immediately after and 55 min after smoking. Correlation coefficients between the concentration of nicotine in each of the 24 plasma samples obtained after smoking and the corresponding values of collagen-induced platelet aggregation and the platelet aggregate ratio were 0.41 (P less than 0.05) and -0.50 (P less than 0.02), respectively. It is concluded that when habitual smokers abstain from smoking overnight, a 20-min period of cigarette smoking may enhance platelet aggregability for as long as 2 h.  相似文献   
42.
Plasma nicotine concentrations following administration by two types of nasal nicotine spray were compared in ten subjects. Absorption was particularly rapid during the first 2.5 min, the average rise in blood nicotine concentrations during this time being 8.6 ng/ml for the two products, followed by a small further rise to an average peak increase of 10.5 ng/ml 5 min after the dose of 2 mg nicotine base (mean 27.8 micrograms/kg). Despite a four-fold Cmax variation between subjects, the levels of individual subjects were fairly consistent across the two products. There were no significant differences between the two products in blood nicotine concentrations or cardiovascular responses, and the correlation between the AUCs from the two products was 0.68 (P = 0.01). Eight subjects reported subjective feelings of light-headedness or slight dizziness, which are not typical after slower absorption from nicotine gum or skin patches. Blood nicotine levels within the smoking range were soon built up with repeated doses, even in the subject with the least efficient nasal absorption. In a second study of ad libitum use under clinical conditions both products appeared sufficiently acceptable for therapeutic use as an aid to smoking cessation. There was no tendency to escalate to excessive use over 4 weeks, and blood nicotine concentrations in nine subjects averaged only 44% of their prior smoking levels. Only one subject had levels equivalent to prior smoking and possible reasons why this was not more common are discussed.  相似文献   
43.
对阳城县3646名15岁以上人群吸烟状况分析表明,男性吸烟率63.71%,女性吸烟率0.64%,男女合计吸烟率31.49%,并对不同年龄、职业、文化程度与吸烟率的关系进行了分析。吸烟心理动机:“烟草成瘾”占32.06%,“消遣”占28.48%,“解除疲劳”占16.90%,“交际”占22.56%。吸烟人群的4周患病率和慢性病患病率均高于不吸烟人群,两组差别有显著性(P<0.05,P<0.001)。  相似文献   
44.
Quality of life was assessed 4–6 months after an acutemyocardial infarction in a randomized double-blind study ofenalapril versus placebo. Quality of life was evaluated usingthe Nottingham Health Profile (NHP), the Physical Symptoms DistressIndex (PSDI), the Work Performance Scale (WPS) and the LifeSatisfaction Index (LSI). The study comprised 36 women (aged46–85 years, mean 68) and 96 males (aged 39–81 years,mean 62). Quality of life did not differ significantly between patientstreated with enalapril versus placebo. The scores were (enalaprilvs placebo, mean± SE): average NHP 15.4 ± 2.3vs 17.1 ± 2.3; PSDI 9.5± 1.0 vs 10.8 ±0.9; WPS 19.8 ± 2.0 vs 19.4 ± 1.4; LSI 24.1 ±1.0 vs 22.5 ±1.4. Men reported a better quality of lifethan women on most assessments, and non-smokers and ex-smokersbetter than smokers. Patients with moderate or severe anginapectoris had a worse quality of life measured by PSDI and NHPthan patients with minimal or no angina pectoris. Patients withcongestive heart failure had a higher PSDI than those without(13.6 ± 1.7 vs 9.4 ± 0.7, P<0.05), while nosignificant differences were observed in the NHP scores. In conclusion, quality of life was similar in enalapril andplacebo- treated patients after an acute myocardial infarction.However, it was reduced in patients with angina pectoris orheart failure and in those who continued smoking.  相似文献   
45.
Lens opacity studies were performed using an electronic Lens Opacity Meter (Interzeag Opacity Lensmeter 701) in a population (n = 321) with ischaemic heart disease. These patients are participating in a trial targetting at the reduction of mortality and incidence of myocardial infarction using a cholesterol-lowering drug, simvastatin. A separate study to evaluate the reliability of the method showed good reproducibility. Repeated measurements after a short time-interval (2–10 days) gave statistically lower opacity values either due to a change in lens transparency or perhaps a change in pigment and cell dispersion in the acqueous caused by repeated mydriasis. Lens opacity values showed a highly significant positive correlation to age. Serum cholesterol, systolic blood pressure and smoking habits showed no significant correlations to the levels of lens opacity when adjustments for age were made.Abbreviations HMG-CoA hydroxy-methylglutarylcoenzyme A - 4S Scandinavian Simvastatin Survival Study - LOM lens opacity meter  相似文献   
46.
4409名学生心理健康状况及家庭环境与吸烟行为分析   总被引:3,自引:0,他引:3  
目的:探讨中学生心理行为特征和心理健康状况及家庭心理环境与中学生吸烟行为的关系.方法:以苏州市4409名初中、高中、职业中学的学生为对象,采用SCL-90、家庭环境量表和自编问题进行问卷调查.结果:反叛性、冒险性强,倾向早熟、毅力差、顺从敏感性高是吸烟的危险因素,而情感调节性和认同敏感性与吸烟无关;吸烟组与对照组SCL-90在总分、阳性项目数、躯体化、强迫症状、人际关系敏感、抑郁、焦虑、敌对、恐怖、偏执、精神病性方面的评分均高于对照组,且有统计学意义(P<0.01);吸烟组在FES-CV中的亲密度、情感表达、知识性、道德宗教观、组织性平均分明显低于对照组(P<0.01),而在FES-CV的矛盾性的平均分则明显高于对照组(P<0.01).结论:中学生行为的反叛性、冒险性、早熟性、毅力性和不良心理健康水平是中学生吸烟的危险因素;同时不良家庭关系也是中学生吸烟的危险因素,一个亲密、融洽的家庭环境可能会减少中学生吸烟,而一个矛盾的家庭则可能会增加中学生吸烟.  相似文献   
47.
AIM: The aim of this study was to compare the population attributable fraction(PAF) for a large baby (> or =4 kg) due to glycaemia, weight and smoking in glucose-tolerant women from different ethnic groups. METHODS: A retrospective review of screening for gestational diabetes (GDM)and associated birth weight was undertaken in New Zealand European (n= 529), Maori (n= 540) and Pacific (n= 916) women. The proportion with a large baby was compared by 1-h post 50-g glucose challenge test tertile and maternal weight tertile. RESULTS: Large babies were more common from Pacific and European than Maori women (24.3%, 18.8%, 8.9%, respectively; P<0.001). Birth weight increased significantly with increasing glucose among Pacific women (P<0.001) even after adjusting for maternal weight and other confounders. The risk of having a large baby was 2.56 (1.82-3.60)-fold greater in women in the highest maternal weight tertile (> or =84 kg), with a significantly greater PAF in Pacific women(27.2%, 12.9%, 16.4%, respectively; P<0.001). The odds ratio (OR) of having a large baby increased with even mildly elevated maternal 1-h glucose concentrations [OR for 5.6-6.2 mmol/l: 1.54 (1.11-2.14); for > or =6.3 mmol/l: 2.06 (1.50-2.82)], with no ethnic differences in PAF (11.1-11.8%, 16.7-18.7%, respectively). Smoking and being Maori were associated with smaller babies. CONCLUSIONS: Increased maternal weight and glycaemia are associated with a greater proportion of large babies among glucose-tolerant women. Growth of Pacific babies may be more sensitive to a higher maternal glucose when the mother is obese.  相似文献   
48.
BACKGROUND: Previous studies on the association between smoking and acne have reported conflicting results. OBJECTIVE: To investigate the association between smoking and acne among school-going adolescents. METHODS: A cross-sectional study was conducted. Smoking was defined as smoking > 3 cigarettes daily for 6 months or more. We defined acne as having > 20 retentional and/or inflammatory facial acne lesions. Multivariate (proportional) logistic regression models were used to adjust for confounding variables. RESULTS: Of the 594 participants, 36.2% had acne. Acne sufferers were less likely to smoke (18.1 vs. 23.7%, P = 0.10). In girls, smoking was significantly associated with lower prevalence of acne (adjusted OR = 0.41, 95% CI = 0.13, 0.82). Smoking, daily cigarette consumption and duration of smoking appeared to be protective in the development of inflammatory acne in girls. No significant associations between acne and smoking variables were detected among boys. Limitations: although this study suggests a significant negative association between smoking and inflammatory acne in girls, it does not prove causality. This association did show a trend for linear relationship. Because of the unexpected differences between boys and girls, sample size may have affected our results. CONCLUSION: The anti-inflammatory effects of smoking may inhibit the development of papulopustular acne in girls more than in boys. However, smoking should not be considered a therapeutic option for acne. Additional studies that consider possible differences across age, gender and type of acne are needed to clarify the association between smoking and acne.  相似文献   
49.
There is a debate about the extent to which the effect of prenatal smoking on infant health outcomes is causal. Poor outcomes could be attributable to mother characteristics, which are correlated with smoking. I examine the importance of selection on the effect of prenatal smoking by using three British cohorts where the mothers' knowledge about the harms of prenatal smoking varied substantially. I find that the effect of smoking on the probability of a low birth weight birth conditional on gestation is slightly more than twice as large in 2000 compared with 1958, implying that selection could explain as much as 50% of the current association between smoking and birth outcomes. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
50.
The increased risk of coronary heart disease in cigarette smokersmay be due at least partly to an elevation of the leucocytecount Chronic passive smoking has also been found to be associatedwith an increased risk of coronary heart disease, but its effecton the leucocyte count has not been reported. In this study250 male factory employees aged 20–64 years were interviewedon smoking behaviour and exposure to environmental tobacco smoke,and blood counts were determined. Urinary cotinine was measureby radio-immunoassay and corrected for urinary creatinine concentrations.Mean leucocyte count was significantly higher among smokerscompared with non-smokers (8,666 compared to 6, 900; p<0.001).On the basis of smoking history, passive smokers had leucocytecounts similar to non-smokers. These findings were confirmedwhen leucocyte counts were compared with urine cotinine to creatinineratios. The association of haematocrlt and haemoglobin withsmoking was similar to that of leucocyte count These findingssuggest that any association of passive smoking with coronaryheart disease is not through an elevation of leucocyte count.  相似文献   
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