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991.
Background: Nurses in the UK are now one group of non-medical staff who can prescribe. This practice is evolving for critical care nursing staff who care for critically ill patients during their stay in hospital through ward and outpatient follow-up after admission to critical care.
Aim: The purposes of this paper were to present existing information regarding prescribing to support nurses in critical care currently prescribing and to inform those who are intending to prescribe.
Methods: To develop the position statement, a search of the literature was conducted using key databases. To ascertain the current level and type of prescribing in critical care, a short questionnaire was sent by email to British Association of Critical Care Nursing members, and the results of this are presented in Appendix A.
Outcomes/Results: Evidence was found in relation to the history, context in critical care, educational requirements and issues of consent related to non-medical prescribing.
Conclusions: The position statement is based upon evidence from the literature, National Health Service policy and the Nursing and Midwifery Council regulations. It takes account of the critical care patient pathway before, during and after an admission to critical care.  相似文献   
992.
993.
This study compared the toxicological responses of Sprague-Dawley rats exposed nose-only to mainstream smoke (MS) from Test cigarettes (1, 2, and 3) to those of Control cigarettes without banded cigarette paper technologies (BCPT). Test cigarettes 1 and 2 had bands based on one technology (different band weight application) while Test cigarette 3 had bands based on another technology. The banded papers are representative of current marketed technologies. Rats were exposed to humidified HEPA filtered air (Sham) or to MS at concentrations of 0.06, 0.20, or 0.80 mg wet total particulate matter per liter air. Each exposure group contained 30 animals/sex (sentinel had 20 animals/sex). The study had two phases (13 weeks each): MS exposure (1 h/day, 5 days/week) and recovery without smoke exposure. Endpoints included clinical observations, respiratory physiology, hematology, serum chemistry, blood carboxyhemoglobin (COHb), serum nicotine, body/organ weights, gross pathology, and histopathology. Comparisons conducted were: Sham exposed vs. all cigarettes, Control cigarette vs. all Test cigarettes, and Test 1 vs. Test 2. Control and Test MS had comparable effects on respiratory physiology, COHb, serum nicotine, serum chemistry, and hematology. While some minor differences were observed, Control and Test MS had comparable effects on clinical signs, body/organ weights, and gross pathology/histopathology. Consequently, exposure of rats to equivalent MS concentrations from the four cigarettes induced similar toxicological responses in this study.  相似文献   
994.
995.
Cerebral blood volume (CBV) studies have provided important insight into the effects of illicit substances such as cannabis. The present study examined changes in regional blood volume in the frontal and temporal lobe, and the cerebellum during 28 days of supervised abstinence from cannabis. Dynamic susceptibility contrast MRI (DSCMRI) data were collected on 15 current, long-term cannabis users between 6 and 36 h after the subjects' last reported cannabis use (Day 0), and again after 7 and 28 days of abstinence. Resting state CBV images were also acquired on 17 healthy comparison subjects. The present findings demonstrate that at Day 7, cannabis users continued to display increased blood volumes in the right frontal region, the left and right temporal regions, and the cerebellum. However, after 28 days of abstinence, only the left temporal area and cerebellum showed significantly increased CBV values in cannabis users. These findings suggest that while CBV levels begin to normalize with continued abstinence from cannabis, specifically in frontal areas, other temporal and cerebellar brain regions show slower CBV decreases.  相似文献   
996.
997.

Background  

Since the 1991 Gulf War concerns have been raised about the effects of deployment to the Gulf War on veterans' health. Studies of the reproductive health of Gulf War veterans have reported varied findings.  相似文献   
998.
PURPOSE: A method and computer tool to estimate percentage magnetic resonance (MR) imaging (MRI) breast density using three-dimensional T(1)-weighted MRI is introduced, and compared with mammographic percentage density [X-ray mammography (XRM)]. MATERIALS AND METHODS: Ethical approval and informed consent were obtained. A method to assess MRI breast density as percentage volume occupied by water-containing tissue on three-dimensional T(1)-weighted MR images is described and applied in a pilot study to 138 subjects who were imaged by both MRI and XRM during the Magnetic Resonance Imaging in Breast Screening study. For comparison, percentage mammographic density was measured from matching XRMs as a ratio of dense to total projection areas scored visually using a 21-point score and measured by applying a two-dimensional interactive program (CUMULUS). The MRI and XRM percent methods were compared, including assessment of left-right and interreader consistency. RESULTS: Percent MRI density correlated strongly (r = 0.78; P < 0.0001) with percent mammographic density estimated using Cumulus. Comparison with visual assessment also showed a strong correlation. The mammographic methods overestimate density compared with MRI volumetric assessment by a factor approaching 2. DISCUSSION: MRI provides direct three-dimensional measurement of the proportion of water-based tissue in the breast. It correlates well with visual and computerized percent mammographic density measurements. This method may have direct application in women having breast cancer screening by breast MRI and may aid in determination of risk.  相似文献   
999.
PURPOSE: Saccharomyces cerevisiae, a nonpathogenic yeast, has been used previously as a vehicle to elicit immune responses to foreign antigens, and tumor-associated antigens, and has been shown to reduce tumor burden in mice. Studies were designed to determine if vaccination of human carcinoembryonic antigen (CEA)-transgenic (CEA-Tg) mice (where CEA is a self-antigen) with a recombinant S. cerevisiae construct expressing human CEA (yeast-CEA) elicits CEA-specific T-cell responses and antitumor activity. EXPERIMENTAL DESIGN: CEA-Tg mice were vaccinated with yeast-CEA, and CD4(+) and CD8(+) T-cell responses were assessed after one and multiple administrations or vaccinations at multiple sites per administration. Antitumor activity was determined by tumor growth and overall survival in both pulmonary metastasis and s.c. pancreatic tumor models. RESULTS: These studies demonstrate that recombinant yeast can break tolerance and that (a) yeast-CEA constructs elicit both CEA-specific CD4(+) and CD8(+) T-cell responses; (b) repeated yeast-CEA administration causes increased antigen-specific T-cell responses after each vaccination; (c) vaccination with yeast-CEA at multiple sites induces a greater T-cell response than the same dose given at a single site; and (d) tumor-bearing mice vaccinated with yeast-CEA show a reduction in tumor burden and increased overall survival compared to mock-treated or control yeast-vaccinated mice in both pulmonary metastasis and s.c. pancreatic tumor models. CONCLUSIONS: Vaccination with a heat-killed recombinant yeast expressing the tumor-associated antigen CEA induces CEA-specific immune responses, reduces tumor burden, and extends overall survival in CEA-Tg mice. These studies thus form the rationale for the incorporation of recombinant yeast-CEA and other recombinant yeast constructs in cancer immunotherapy protocols.  相似文献   
1000.
Primary care nurses are very likely to provide a substantial part of the routine care for patients with dementia. In order to examine the knowledge and attitudes of the primary care nurses who undertake the Over-75 Check, towards assessing and managing patients with symptoms of dementia, and to assess their level of support for a clinical practice guideline, a postal questionnaire survey was undertaken of primary care nurses responsible for the Over-75 Check in 209 general practices in Gloucester, Avon and Somerset. The questionnaire ascertained some demographic information about the nurses, their training and the practice routine for the Over-75 Check. It also included a case vignette describing a typical presentation of dementia at an Over-75 Check. A 65% response rate was achieved. Only one-fifth of respondents ever used formal validated cognitive tests as part of the Over-75 Check. In response to the vignette, nearly 10% took no action at all and a further 25% simply referred the patient on. Amongst the remainder there was considerable variation regarding the tasks considered to be within their remit. The respondents strongly supported the introduction of guidelines. Given the variation in professional responsibilities between practices, it is proposed that a clinical practice guideline covering diagnosis, assessment and management of dementia should address the practice as a whole rather than be targeted to specific professionals. The guideline should prompt professionals carrying out an Over-75 Check to recognize symptoms of dementia and raise awareness of the range of tasks which need to be undertaken in confirming diagnosis, assessing needs and managing patients. Results from this study suggest that improved training and increased autonomy for primary care nurses would improve access to services for these patients and their carers.  相似文献   
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