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991.
Hyperacusis and otitis media in individuals with Williams syndrome   总被引:2,自引:0,他引:2  
Williams syndrome is characterized by cardiac defects, varying degrees of physical and developmental delay, stellate eye pattern, possible elevated serum calcium level, and elfin/pixie facial features. A problem perhaps unique to these children is hyperacusis that can be severe enough to disrupt many routine daily activities. Parental questionnaires were used to determine the prevalence of hyperacusis and otitis media in individuals with Williams syndrome. Prevalences of 95% for hyperacusis and 61% for otitis media were found. This was significantly higher than in the general population. Despite the prevalence of hyperacusis, parents of these children were not counseled about management of the problem. The audiologist may become involved with Williams syndrome patients through hearing assessment and management, parental counseling, and research.  相似文献   
992.
Diaphragm pacing stimulation (DPS) for ventilator‐dependent patients provides several advantages over conventional techniques such as phrenic nerve pacing or mechanical ventilator support. To date, the only existing system for DPS uses lead electrodes, percutaneously attached to an external pulse generator (PG). However, for a widespread use of this technique it would be more appropriate to eliminate the need for percutaneous wire and use a totally implantable system. The aim of this study was to determine if it were feasible to replace the external PG by an implantable system. We present here the results of a preliminary study of two different PG, currently used in other electrical stimulation (ES) clinical applications, which could be used as implantable DPS systems. One radio‐frequency‐powered PG, one rechargeable battery‐powered PG, and the current external PG were tested. Each was attached to the externalized part of the wires, connected to the diaphragm and tidal volume (TV) was measured in one ventilator‐dependent patient who has been using the current percutaneous stimulator for 3 years. Results indicated that both implantable PGs could achieve equivalent ventilatory requirements to the current external stimulator. No significant differences were observed between the three PG systems when stimulating the electrodes as used in the patient's own chronically attached PG system. We found that TV increased with increases in charge and frequency as expected when stimulating the patient's electrodes individually and in combination with each PG system. These results are a significant step toward developing a totally implantable DPS system for the ventilator‐dependant patients. Further clinical tests to demonstrate the safety and efficacy of a fully implanted DPS system are warranted.  相似文献   
993.
SOCIAL USES OF MEDICINE   总被引:1,自引:0,他引:1  
Seventy percent of our people need medical or dental treatment, but go without because of lack of proper medical organization. Dr. Armstrong is not merely critical, but is constructive. He shows the absurdity of making physicians dependent on sickness for support, and outlines a plan of community procedure on a rational basis.  相似文献   
994.
Surveys from several countries have identified the presence of risk factors known to be associated with coronary heart disease in children. Data on the distribution of coronary risk factor variables in British children are scarce. This study was therefore designed to test the feasibility of collecting coronary risk factor data from British children and to conduct a preliminary examination of the problem. One hundred and seven children (mean age 12.8 yr) had their height, weight, triceps skinfold and blood pressure checked. Blood samples for cholesterol and HDL-cholesterol analysis were obtained from 93 children. Peak VO2 was determined on 48 children, 76 children had their daily activity monitored and 59 children's stage of sexual maturity was assessed. The boys' peak VO2 was significantly higher than the girls, whether expressed in l.min-1 (p less than 0.05) or ml.kg.-1min-1 (p less than 0.01). No other significant differences (p greater than 0.05) between the sexes were detected. The results indicate that children have relatively high serum cholesterol levels (boys 4.58 +/- 0.79; girls 4.72 +/- 0.80 mmol.l-1). The willingness and enthusiasm of the children, parents and schools to take part in the study clearly demonstrated the feasibility of a large scale study being successfully pursued in the United Kingdom.  相似文献   
995.
The Delphi technique, with an evaluation panel of 56 educators from 28 states during Round One and 55 in Round Two, was used as a method of collecting and organizing judgments of present and future needs for computer competence. Competence statements covered psychomotor, cognitive and affective issues in using the computer and related technology in nursing practice and teaching. Judged to be highly important were 45 of the 68 possible present needs and 44 of the 64 future needs. It was concluded that the most pressing needs for nursing educators are for knowledge of computer technology, information on how to use the computer as an instructional tool, recognition of the nurse's role and issues of computer use in health care and use of the nursing process in the development of computerized care plans.  相似文献   
996.
Study objective:To determine the optimal strategy for the timing of aortic valve replacement in patients with chronic, severe aortic regurgitation with left ventricular dysfunction. Design:Decision analysis comparing early surgery (timed at the onset of left ventricular dysfunction) with delayed surgery (timed at the onset of symptoms) using data from the literature and expert opinion for variables in a representative case scenario (40-year-old man with bicuspid aortic valve disease). Setting:Tertiary care center doing valve replacement surgery. Measurements and main results:The early-surgery approach was preferred based on quality-adjusted life years. Sensitivity analysis showed that the result was not affected by the following variables within their derived ranges: rate of symptom development after onset of left ventricular dysfunction for the delayed-surgery approach, perioperative mortality for both approaches, and occurrence of major monfatal stroke or congestive heart failure for both approaches. Although the decision was sensitive to the yearly postoperative mortality rates, the delayed-surgery operative mortality rate had to be almost as low as the early-surgery rate to change the preference to the delayed-surgery approach. The preference could also change if survival were much more important to the patient in the first five years than after five years or if the patient disliked living on anticoagulants enough to value a year on anticoagulants as worth only 80% of a year not on anticoagulants. Conclusion:This decision analysis provides quantitative support for the impression that patients similar to the case scenario do better with surgery timed at the onset of ventricular dysfunction than with surgery delayed until symptoms develop. It thus supports the practice of following these patients noninvasively in order to time surgery. Received from the Departments of Medicine and Health Administration, University of Toronto; Division of Cardiology, St. Michael’s Hospital; and Division of General Internal Medicine and Clinical Epidemiology, Toronto General Hospital, Toronto, Ontario, Canada. Supported in part by a National Health Research Award (Health and Welfare, Canada) to Dr. Detsky.  相似文献   
997.
AIM: Hydrogen sulfide (H2S) is a prominent gaseous constituent of the gastrointestinal (GI) tract with known cytotoxic properties. Endogenous concentrations of H2S are reported to range between 0.2-3.4 mmol/L in the GI tract of mice and humans. Considering such high levels we speculate that, at non-toxic concentrations, H2S may interact with chemical agents and alter the response of colonic epithelium cells to such compounds. The GI tract is a major site for the absorption of phytochemical constituents such as isothiocyanates, flavonoids, and carotenoids, with each group having a role in the prevention of human diseases such as colon cancer. The chemopreventative properties of the phytochemical agent β-phenyethyl isothiocyanate (PEITC) are well recognized. However, little is currently known about the physiological or biochemical factors present in the GI tract that may influence the biological properties of ITCs. The current study was undertaken to determine the effects of H2S on PEITC mediated apoptosis in colon cancer cells.METHODS: Induction of apoptosis by PEITC in human colon cancer HCT116 cells was assessed using classic apoptotic markers namely SubG1 population analysis,caspase-3 like activity and nuclear fragmentation and condensation coupled with the MTT (3-(4,5-dimethylthiazol2-yl)-2,5-diphenyl tetrasodium bromide) viability assay and LDH leakage.RESULTS: PEITC significantly induced apoptosis in HGT116cells as assessed by SubG1 population formation, nuclear condensation, LDH leakage and caspase-3 activity after 24 h, these data being significant from control groups (P<0.01). In contrast, co-treatment of cells with physiological concentrations of H2S (0.1-1 mmol/L) prevented PEITC mediated apoptosis as assessed using the parameters described.CONCLUSION: PEITC effectively induced cell death in the human adenocarcinoma cell line HCT116 in vitro through classic apoptotic mechanisms. However, in the presence of H2S, apoptosis was abolished. These data suggest that H2S may play a significant role in the response of colonic epithelial cells to beneficial as well as toxic agents present within the GI tract.  相似文献   
998.
ABSTRACT:  Context: Appalachia has been characterized by its poverty, a factor associated with tuberculosis, yet little is known about the disease in this region. Purpose: To determine whether Appalachian tuberculosis risk factors, trends, and rates differ from the rest of the United States. Methods: Analysis of tuberculosis cases reported to the Centers for Disease Control and Prevention's National Tuberculosis Surveillance System (NTSS) within the 50 states and the District of Columbia from 1993 through 2005. Results: The 2005 rate of tuberculosis in rural Appalachia was 2.1/100,000, compared to 2.7/100,000 in urban Appalachia. Urban non-Appalachia had a 2005 tuberculosis rate of 5.4/100,000. Over the 13-year period, tuberculosis rates fell in Appalachia at an annual rate of 7.8%. In one age group (15- to 24-year-olds) the rates increased at an annual rate of 2.8%. Foreign-born Hispanics were the largest racial/ethnic group in this age group. When private providers gave exclusive care for tuberculosis disease, Appalachians were less likely to complete therapy in a timely manner when compared to non-Appalachians (OR 0.6, 95% CI 0.5-0.7). Conclusions: Tuberculosis rates and trends are similar in urban and rural Appalachia. It is crucial for public health officials in Appalachia to address the escalating TB rate among 15- to 24-year-olds by focusing prevention efforts on the growing numbers of foreign-born cases. Due to the increased risk of treatment failure among Appalachians who do not seek care from the health department, public health authorities must ensure completion of treatment for patients who seek private providers.  相似文献   
999.
1000.
Serotonin, which is released when platelets aggregate at carotid lesions, may contribute to cerebral ischemia. Our goal was to test the hypothesis that dietary treatment of atherosclerosis reverses the augmented cerebral vasoconstrictor response to serotonin. We studied normal cynomolgus monkeys, atherosclerotic monkeys, and atherosclerotic monkeys that were fed a normal (regression) diet for 18 months. Morphometric studies indicated that the regression diet reduced intimal area in the carotid arteries by about 50-75%. Cerebral blood flow was measured with microspheres, and microvascular pressure was measured with a micropipette in pial arteries that were approximately 300 micron in diameter. Values for cerebral blood flow and arteriolar pressure were used to calculate resistance of large cerebral arteries (greater than 300 micron diameter). Infusion of serotonin produced a modest increase in the resistance of large cerebral arteries in normal monkeys. Vasoconstrictor responses to serotonin were increased more than fivefold in atherosclerotic monkeys. The major finding of the study is that dietary treatment of atherosclerosis abolishes augmented cerebral responses to serotonin.  相似文献   
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