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91.
Baltogiannis D Tasos A Voutsinas G Dauaher H Chambilomatis P Giannakopoulos X 《International urology and nephrology》2001,32(3):377-379
Objective: To describe the pattern of bladder cancer mortality in the Epirus district population (North-Western Greece) and to establish
some relationships with cigarette smoking. Patients and methods: Mortality rates of bladder cancer in the Epirus district population were analysed according to the official data from the
Department of Statistics of the University Hospital of Ioannina during the last decade (January 1990–January 2000). Age –standardization
of death rates was done by the direct method, using the world population as a standard. Fisher's test was used as a significance
test for linear regression coefficient in time trend analysis of mortality. Results: The average annual standardized mortality rates from bladder cancer during the study period were 5.23 per 100,000population
(96% Confidence Interval – CI 4.02–5.63)in males and 1.63 per 100,000 population (96% Confidence Interval– CI 1.18–1.96) in
females. Significantly increasing trends of the rates were observed in males (y = 2.421 + 0.231x; p < 0.01), but not in females (y = 1.263 +0.027x; p > 0.05). The greatest increase in age –specific rates in males was observed in the age group of 70 and more years (y = 25.602
+ 3.673x; p < 0.01). In females,all age – specific rates except for the group 60–69 years showed significantly increasing tendency. The
increasing tendency of bladder cancer mortality is followed by the rise of per capita cigarette consumption among the Epirus
district population. Conclusion:Further studies are needed for the explanation of the irregularities in the age-specific rates.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
92.
RATIONALE: Although adolescent smokers appear to display some of the hallmark features of dependence, the biological and behavioral effects of smoking in this population are poorly understood. OBJECTIVES: This study aimed to define empirically the effects of abstinence and smoking in adolescent smokers, using indices validated in adult smokers. METHODS: Subjects were 16 young novice smokers (five male, 11 female), ages 14-18 years. A modified Stroop task measured the ability to inhibit attention to smoking-related cues; the classic Stroop task measured the ability to inhibit a pre-potent response (i.e. reading a word); a rapid information processing (RIP) task measured vigilance. RESULTS: Abstinence increased and smoking decreased the intrusiveness of smoking cues. Parallel effects were seen in commission errors on the RIP task. These effects were restricted to heavier smokers (>11 cigarettes/day). Subjective withdrawal effects predicted the intrusiveness of smoking words during abstinence. The number of cigarettes smoked per day predicted the beneficial effect of smoking on the classic as well as modified Stroop tasks. The physiological effects of abstinence and smoking predicted RIP performance. CONCLUSIONS: Abstinence impairs and smoking improves inhibitory information processing in young novice smokers in a manner similar to adult smokers. Daily frequency of smoking is a critical moderator of these effects. 相似文献
93.
Exposure to airborne pollutants such as tobacco smoke is associated with increased activation of inflammatory-immune processes and is thought to contribute to the incidence of respiratory tract disease. We hypothezised that cigarette smoke (CS) could synergize with activated inflammatory/immune cells to cause oxidative injury or result in the formation of unique reactive oxidants. Isolated human neutrophils were exposed to gas-phase CS, and the production of nitrating and chlorinating oxidants following neutrophil stimulation was monitored using the substrate 4-hydroxyphenylacetate (HPA). Stimulation of neutrophils in the presence of CS resulted in a reduced oxidation and chlorination of HPA, suggesting inhibition of NADPH oxidase or myeloperoxidase (MPO), the two major enzymes involved in inflammatory oxidant formation. Peroxidase assays demonstrated that neutrophil MPO activity was not significantly affected after CS-exposure, leaving the NADPH oxidase as a likely target. The inhibition of neutrophil oxidant formation was found to coincide with depletion of cellular GSH, and a similar modification of critical cysteine residues, such as those in NADPH oxidase components, might be involved in reduced respiratory burst activity. As ,β-unsaturated aldehydes such as acrolein have been implicated in thiol modifications by CS, we exposed neutrophils to acrolein prior to stimulation, and observed inhibition of NADPH oxidase activation in relation to GSH depletion. Additionally, translocation of the cytosolic components of NADPH oxidase to the membrane, a necessary requirement for enzyme activation, was inhibited. Protein adducts of acrolein (or related aldehydes) could be detected in several neutrophil proteins, including NADPH oxidase components, following neutrophil exposure to either CS or acrolein. Alterations in neutrophil function by exposure to (environmental) tobacco smoke may affect inflammatory/infectious conditions and thereby contribute to tobacco-related disease. 相似文献
94.
RATIONALE: Psychomotor stimulants previously have been found to increase the frequency of cigarette smoking, but it is unclear whether this is due to a non-specific increase in general activity or a specific increase in the reinforcing effects of smoking. OBJECTIVES: To investigate whether d-amphetamine increases the relative reinforcing effects of cigarette smoking. METHODS: Ninety minutes after d-amphetamine (7.5, 15 mg/70 kg) or placebo administration, 13 male and female subjects participated in 3-h sessions during which they could make a maximum of 20 choices between cigarette smoking (two puffs per choice), earning money ($0.25 per choice), or neither. In separate sessions, using the same subjects, the effects of d-amphetamine on the frequency of ad libitum smoking was assessed. RESULTS: During choice sessions, d-amphetamine dose-dependently increased smoking choices from 4.2 +/- 0.6 to 5.7 +/- 0.6. During sessions in which subjects smoked ad libitum, d-amphetamine increased number of cigarettes smoked from 2.8 +/- 0.4 to 3.8 +/- 0.6. Breath carbon monoxide (CO) levels, a measure of smoke exposure, showed corresponding dose-related increases. CONCLUSIONS: These results are consistent with previous findings that d-amphetamine increases smoking and provide evidence that this effect is due to a drug-produced increase in the relative reinforcing effects of cigarette smoking. 相似文献
95.
目的从源头上预防、控制和消除某烟标印刷建设项目可能产生的职业病危害,保障劳动者身体健康。方法进行职业卫生学调查,检测职业病危害因素,并对劳动者进行职业健康检查。结果该项目职业卫生情况较好;生产性毒物乙酸乙酯、异丙醇、二甲苯TWA检测值分别为164.9~193.0、67.1~127.1、1.7~6.3mg/m^3,STEL,检测值为204.4~266.0、83.0~190.2、4.3~9.0mg/m^3,生产性噪声强度为83.7~85.0dB(A),均符合国家职业卫生标准;职业健康检查未发现职业病观察对象或患者。结论该建设项目为一般职业病危害的建设项目,职业病危害控制效果基本符合相关法律法规、标准和规范的要求,厂方应继续落实各项职业卫生管理措施。 相似文献
96.
Yuan Xue Tracy L. Williams Ting Li Joshua Umbehr Liang Fang Weiqun Wang Richard C. Baybutt 《Toxicology in vitro》2005,19(8):1061-1069
This study was to evaluate the effects of cigarette smoke constituents upon type II pneumocyte surfactant production in vitro, and how vitamins A and E may alter the response. Freshly isolated type II pneumocytes from Sprague–Dawley rats were incubated 20 h in medium with fetal bovine serum that was or was not treated with cigarette smoke. The number of adherent cells was inversely related to the dose of smoke or benzo(a)pyrene. Despite the decreased number of treated cells, the total amount of surfactant per culture well was unchanged, whereas surfactant production per cell was significantly increased (P < 0.05). Vitamin A concentration was significantly (P < 0.05) lower in the smoke-treated serum compared with untreated serum. When vitamin A or E was added to the cigarette smoke-treated serum, cell adherence and surfactant production returned to control values. In conclusion, cigarette smoke constituents or benzo(a)pyrene alone decreased the number of adherent type II pneumocytes, but did not alter surfactant amounts because of an increased production of surfactant per cell. Type II pneumocytes seem to adjust surfactant production dependent upon the number of type II pneumocytes to produce it and vitamin A or E enhance cell attachment in the presence of the smoke toxins. 相似文献
97.
Puffing behavior (number of puffs, puff duration, puff volume, peak pressure, peak flow, peak latency, and puff interval) and pre- to postsmoking delta tidal CO difference were measured in female subjects in order to assess separate and combined effects of ethanol and caffeine. The subjects smoked two cigarettes of their habitual brand in a preliminary familiarizing session and in each of the subsequent four test sessions. The treatments administered after smoking the first cigarette in the test sessions were: alcohol placebo and caffeine placebo; alcohol placebo and caffeine; alcohol and caffeine placebo; alcohol and caffeine. Test-retest reliability across the first cigarette of each session (which was not smoked under the influence of the treatments) was remarkably high for all the puffing parameters. Ethanol in the dose of 0.7 g/kg intensified cigarette smoking of the second cigarette by increasing delta tidal CO, average puff volume, and total puff volume per cigarette, whereas 0.5 g/kg ethanol and 5 mg/kg caffeine given alone or combined with ethanol failed to influence puffing behavior consistently. 相似文献
98.
G. Sutherland M. A. H. Russell J. Stapleton C. Feyerabend O. Ferno 《Psychopharmacology》1992,108(4):512-518
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
99.
The aim of this present study was to compare the use by smokers and non-smokers of pamphlets about smoking as delivered from different settings. The study was a nation-wide cross-sectional survey of 1924 randomly selected, Danish men and women, aged 14–77 y, who had answered a mailed questionnaire in 1994. Of these 71% also participated in a telephone interview enquiring about the use of health education material, smoking status and socio-demographic variables, 39% of readers of household-delivered anti-smoking pamphlets reported having gained information from them and 22% reported having made changes in their own smoking behaviour such as avoiding smoking in the presence of non-smokers. In general practice settings, these percentages were higher among smokers. Smokers who were thinking of stopping smoking in the near future were in addition more likely to take and to read smoking related health education materials from other places. Non-smokers received (3–49%) and read pamphlets about smoking as frequently as did smokers who did not intend to quit. In conclusion, written health education material was well received by readers, but, when distributed in a more open setting it needs to be targeted towards smokers who are considering stopping smoking. In general practice, smokers not thinking of stopping were open to health education, and pamphlets used in this setting should also target this group. Non-smokers contribute indirectly to smokers quitting by providing support to smokers and pamphlets for non-smokers need to be more targeted towards this social role. 相似文献
100.