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81.
Ashley J 《Health trends》1990,22(4):135-137
The Tenth Revision of the International Classification of Diseases is due to be published this year, and introduced from 1993. The aim of the classification is to facilitate comparisons between countries at the same point in time and within, and between, countries over time. The provision of comparable statistics is essential for facilitating policy decisions relating to health promotion and disease prevention, and for the collection of epidemiological data for research purposes. This article describes the major changes and important features in this revision, and compares them to the Ninth Revision of the International Classification of Diseases.  相似文献   
82.
Plant foods have been associated inversely with colon cancer. Since amajor focus of this study was to identify components of plant foods whichmay account for their association with colon cancer, nutrients which arecommonly found in plant foods also were evaluated. A population-basedcase-control study was conducted in Northern California, Utah, and the TwinCities area of Minnesota (United States). Complete data were available frominterviewer-administered questionnaires on 1,993 cases and 2,410 controls.Higher intakes of vegetables (for highest relative to lowest quintile ofintake) were associated inversely with colon cancer risk: the odds ratio(OR) was 0.7 for both men (95 percent [CI] confidence interval = 0.5-0.9)and women (CI = 0.5-1.0). Associations were stronger among those withproximal tumors. Total fruit intake was not associated with colon cancerrisk although, among men, higher levels of whole grain intake wereassociated with a decreased risk (OR = 0.6, CI = 0.4-0.9 for older men);high intakes of refined grains were associated with an increased risk (OR =1.5, CI = 1.1-2.1). Dietary fiber intake was associated with a decreasedrisk of colon cancer: OR = 0.5 (CI = 0.3-0.9) for older men; OR = 0.7 (CI =0.4-1.2) for older women; OR = 0.6 (CI = 0.4-1.0) for men with proximaltumors; OR = 0.5 (CI = 0.3-0.9) for women with proximal tumors. Othernutrients, for which plant foods were the major contributor - such asvitamin B6, thiamin, and niacin (women only) - also were associatedinversely with colon cancer. Neither beta-carotene nor vitamin C wasprotective for colon cancer. Adjustment of plant foods for nutrients foundin plant foods or for supplement use did not appreciably alter the observedassociations between plant foods and colon cancer.  相似文献   
83.
Between March and November of 1991, approximately 9000 workers from 43 different countries battled the burning oil wells in Kuwait. To document the exposure of persons in Kuwait during the oil well fires to volatile organic compounds (VOCs), we obtained samples of blood from 14 U.S. personnel in Kuwait City in May of 1991 (group I) and 40 American firefighters working in the oil fields in October of 1991 (group II). Concentrations of VOCs in group I and group II were compared with those of a random sample of 114 persons in the United States (reference group). The median concentrations of VOCs in group I were equal to or lower than those in the reference group. We found significant differences between the median concentrations of several VOCs in group 11 and the reference group. Median levels of ethylbenzene were about 10 times higher among group II than among the reference group (0.53 g/I vs 0.052 g/l). Median levels of benzene, m-/p-xylene, o-xylene, styrene, and toluene among group II were more than double those of the reference group. Although firefighters had higher median concentrations of VOCs than the reference group, those American personnel in Kuwait not involved in fighting the oil fires had concentrations of VOCs comparable to those in the reference group. Blood VOC measurements indicate a significant increase in exposure to VOCs in firefighters, but do not demonstrate this in personnel in Kuwait City.  相似文献   
84.
Chemical protective clothing (PC) use while working results in elevated rectal temperatures (Tre) that limit work time. Particle barrier, vapor permeable (PBVP) PCs allow workers to cool themselves by evaporating some sweat. The purpose of this study was to compare the effects on worker productivity of two types of PBVP suits, a Kleenguard (PPPC) (Kimberly Clark), and a Tyvek (PEPC) (DuPont) suit. Fifteen males in a repeated measures design performed four work tests consisting of a walk/arm curl combination at a time-weighted work rate of 1.0 L/min (300 kcal/hr), two in a wet bulb globe temperature (WBGT) of 26 degrees C and two in a WBGT of 18 degrees C, with subjects wearing each suit once in each environment. No significant difference (p > 0.05) was observed between the suits at 18 degrees C WBGT, but a significant difference was found (p < 0.05) between the suits, with the PPPC having a lower Tre in the WBGT = 26 degrees C at the 80th, 100th, and 120th min. A significant difference (p < .05) was also seen in the 26 degrees C WBGT with the PPPC resulting in a lower heart rate (HR) at the 40th, 60th, 80th, 100th, and 120th min and rate of perceived exertion (RPE) at the 75th, 90th, and 120th min. Additionally, a significant difference (p < .05) was seen between PEPC and PPPC for Tre, delta Tre, mean skin temp (mTsk), delta mTsk, and HR, each regressed against time in the 26 degrees C WBGT. Twelve of the 15 subjects also reported feeling cooler in the PPPC versus the PEPC in either WBGT environment.  相似文献   
85.
Few studies have employed a qualitative approach to better understand how both smokers and non-smokers experience and make sense of no-smoking restrictions in their daily lives. We describe qualitative research involving an examination of self-reported interpersonal interactions between smokers and non-smokers in public places regarding exposure to environmental tobacco smoke (ETS). Five focus group discussions and twenty individual in-depth interviews were conducted with smokers and non-smokers in the Metropolitan Toronto region as a complement to a quantitative survey of the adult population of Ontario. Strategies used by non-smokers in responding to ETS exposures included verbal confrontations, non-verbal cues, use of a third party, and moving away. The perceived consequences of such actions, as described by both smokers and non-smokers, are discussed, together with implications for tobacco control policy and practice.  相似文献   
86.
BACKGROUND: The Physiological and Operative Severity Score for enUmeration of Mortality and morbidity (POSSUM) is a simple scoring system previously validated in general surgical patients which enables estimation of the risk of complications and death after operation. The Portsmouth predictor equation (P-POSSUM) is a modification that may result in more accurate prediction of death than POSSUM. The aim of this study was to test the validity of POSSUM and P-POSSUM in patients undergoing major arterial surgery in a specialist unit. METHODS: Physiological and operative severity scores in 221 patients undergoing elective and emergency arterial surgery in a pure vascular practice under a single consultant were recorded prospectively. Observed morbidity and mortality rates were compared with the rates predicted by POSSUM and P-POSSUM using a linear method of analysis. RESULTS: The POSSUM equation overestimated deaths with this analysis but the mortality rate estimated by P-POSSUM was not significantly different from the observed death rate. The risk of morbidity predicted by POSSUM was not significantly different from the observed complication rate. CONCLUSION: The POSSUM methodology combined with the P-POSSUM adjustment for death allows satisfactory prediction of mortality and morbidity rates in patients undergoing vascular surgery.  相似文献   
87.
Pesticides are used on a massive scale in the United States. The widespread use of these pesticides has made it virtually impossible for the average person to avoid exposure at some level. Generally, it is believed that low-level exposure to these pesticides does not produce acute toxic effects; however, various cancers and other noncancer health endpoints have been associated with chronic exposure to several groups of pesticides. Therefore, it is imperative that well-designed studies investigate the potential relationship between contemporary pesticide exposure and health effects. For these studies to be accurate, reliable methods for determining individual exposure must be used. Biological monitoring is a useful tool for assessing exposure to some contemporary pesticides. As with any analytical method, biological monitoring entails many difficulties, but, in many instances, they can be overcome by the logical use of available information and information acquired in carefully designed studies. At the Centers for Disease Control and Prevention (CDC), we have acquired extensive experience in the development and application of specific techniques for biological monitoring of a variety of toxicants, including many of the contemporary-use pesticides. We have used these methods to measure the internal dose of pesticides received by people in acute and chronic incidents resulting from both environmental and industrial exposure. Additionally, we have established normative values, or reference ranges, of several pesticides based on measurements of their metabolites in the urine of randomly selected adults in the US population. These data have been successfully used to distinguish overt exposures from 'background' exposure. In this paper, we present several examples of the usefulness of biological monitoring in urine and blood and describe the difficulties involved with developing methods in these matrices. We also present a general strategy, considerations, and recommendations for developing biological monitoring techniques for measuring the internal dose of contemporary-use pesticides.  相似文献   
88.
Objective: This study was undertaken to evaluate the changes in total and anti-herpes simplex virus (HSV)-specific cervical IgA and IgG antibody profiles during and after pregnancy.Methods: Serum and cervical secretions were obtained from pregnant patients before 20 weeks gestation, at 34-36 weeks gestation, and at 6 weeks postpartum and tested for total IgA and IgG antibody and for IgA and IgG to HSV proteins by Western blot.Results: Seven women were HSV seronegative, 14 HSV-1 seropositive, and 14 HSV-2 +/- HSV-1 seropositive. Minimal changes in the serum anti-HSV profiles were seen over the 3 visits. The total cervical IgA, IgG, and protein levels did not change between the 2 pregnancy visits but tended to increase at the postpartum visit. No consistent change in cervical HSV-specific IgA and IgG was seen during pregnancy, but the levels increased markedly at the postpartum visit.Conclusions: Lower cervical anti-HSV antibody levels may be related to the previously reported increased frequency of a reactivation of HSV during late pregnancy. Further evaluation is necessary to confirm and quantify the changes in genital immunity during pregnancy and to evaluate whether the increased levels at the postpartum visit are sustained.  相似文献   
89.
Ten years after Humanae Vitae, Human Sexuality, a study commissioned by the Catholic Theological Society of America, is being widely discussed. The four propositions that served as the study's theoretical base are examined in an attempt to "better appreciate and evaluate the present significance of Humanae Vitae for Catholics in general and for Catholic health care professionals in particular."  相似文献   
90.
Christians and humanists accept an evolutionary world view and respect those fundamental relations underlying evolutionary development. Both value systems should be able to discuss seriously the risks of altering one of the most fundamental of all relations: that of child to parent.  相似文献   
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