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41.
42.
We conducted a study of the epidemiology of myasthenia gravis (MG) in four locations in central and western Virginia from 1970 through 1984. The population surveyed was 555,851 in 1984. A total of 73 new cases of MG occurred during the survey period, producing an overall average annual incidence rate of 9.1 per million. The point prevalence rate in 1980 was 13.4 per 100,000, and in 1984 it was 14.2. Approximately 15% of the population was black, and we found that incidence and prevalence rates for the black population were higher than the corresponding white population. When the population was subdivided into <50 and 50+ age groups, the incidence and prevalence were significantly higher in the older group. The rates we report here are higher than rates reported from any other locality. The reasons for the higher rates include optimal case identification, survey of a population with a higher incidence, and increasing aging of the population. 相似文献
43.
Intensive versus standard blood glucose awareness training (BGAT) with insulin-dependent diabetes: mechanisms and ancillary effects 总被引:1,自引:0,他引:1
D J Cox L Gonder-Frederick D Julian P Cryer J H Lee F E Richards W Clarke 《Psychosomatic medicine》1991,53(4):453-462
Insulin-dependent diabetes mellitus (IDDM) patients make critical daily self-care decisions on the basis of what they estimate their blood glucose (BG) levels to be. This study: a) replicated efficacy of Standard Blood Glucose Awareness Training (BGAT), b) evaluated the relative efficacy of an Intensive Blood Glucose Awareness Training (BGAT) to enhance patient accuracy of BG estimation, and c) evaluated the mechanisms and ancillary effects of BGAT. Thirty-nine subjects were randomly assigned to one of three groups. Compared with Control, both Standard and Intensive BGAT improved accuracy (p less than 0.001). Intensive BGAT post-treatment accuracy relative to Standard BGAT did not reach statistical significance (p = 0.177). Greater improvement in accuracy was associated with poorer pretreatment accuracy. Only Intensive BGAT improved metabolic control (glycosylated hemoglobin), and this improvement was associated with poorer pretreatment control. The effects of BGAT were highly specific, affecting only accuracy and metabolic control, and not affecting fear of hypoglycemia, diabetes knowledge, of frequency of blood glucose monitoring. 相似文献
44.
Ehsanollah Esfandiari Michael Bailey Christopher R Stokes Timothy M Cox Martin J Evans Alison R Hayman 《Journal of bone and mineral research》2006,21(9):1367-1376
TRACP, a marker of osteoclasts, is also expressed by cells of the immune system. We identified a novel function for TRACP in the dendritic cell. DCs from TRACP knockout mice have impaired maturation and trigger reduced Th1 responses in vivo. We postulate that TRACP has an important role in the presentation of antigens to T cells. INTRODUCTION: TRACP is highly expressed by osteoclasts, activated macrophages, and dendritic cells (DCs). Knockout mice lacking TRACP have an intrinsic defect in osteoclastic resorption and macrophages that display abnormal immunomodulatory responses and cytokine secretion profiles. Our aim in this study was to investigate the significance of TRACP in the inductive phase of the immune response by examining dendritic cells from TRACP(-/-) mice. MATERIALS AND METHODS: Maturational state and function of leukocyte subsets in mice was assessed by flow cytometry. The ability of the immune system to respond to nonspecific activation and to specific antigen was assessed by delayed type hypersensitivity and the presence of isotype-specific serum antibody in vivo and T-cell proliferation and cytokine production in vitro. RESULTS: The ability of lipopolysaccharide (LPS) to upregulate MHC II and CD80 in DCs from TRACP(-/-) mice was reduced compared with wildtype mice, although production of IL-10 by DCs from TRACP-deficient animals was increased. T- and B-cell responses not involving antigen presentation (anti-CD3, TNP-ficoll) were normal in TRACP(-/-) mice, but responses to T-dependent antigens were impaired. Specifically, TRACP(-/-) mice had defective delayed hypersensitivity responses to picryl chloride and reduced proliferative responses to ovalbumin compared with wildtype mice. In response to ovalbumin, but not anti-CD3, T cells from TRACP(-/-) mice produced less interferon-gamma (IFN-gamma), but there was no difference in IL-4 production: TRACP(-/-) mice also produced less ovalbumin (OVA)-specific IgG2a after immunization. CONCLUSIONS: The finding that DCs from TRACP(-/-) mice have impaired maturation and defective Th1 responses shows that TRACP is important for polarizing responses in na?ve T cells to antigen-presented dendritic cells. 相似文献
45.
Effect of 30 per cent maternal nutrient restriction from 0.16 to 0.5 gestation on fetal baboon kidney gene expression 总被引:4,自引:1,他引:3
46.
Charles I. Cox Raju Metherate Norman M. Weinberger John H. Ashe 《Brain research bulletin》1992,28(3):401-410
Neurons of in vitro guinea pig and rat auditory cortex receive a complex synaptic pattern of afferent information. As many as four synaptic responses to a single-stimulus pulse to the gray or white matter can occur; an early-EPSP followed, sequentially, by an early-IPSP, late-EPSP, and late-IPSP. Paired pulse stimulation and pharmacological studies show that the early-IPSP can modify information transmission that occurs by way of the early-EPSP. Each of these four synaptic responses differed in estimated reversal potential, and each was differentially sensitive to antagonism by pharmacological agents. DNQX (6,7-dinitroquinoxaline-2,3-dione), a quisqualate/kainate receptor antagonist, blocked the early-EPSP, and the late-EPSP was blocked by the NMDA receptor antagonist APV (D-2-amino-5-phosphonovalerate). The early-IPSP was blocked by the GABA-a receptor antagonist bicuculline, and the late-IPSP by the GABA-b receptor antagonists 2-OH saclofen or phaclofen. Presentation of stimulus trains, even at relatively low intensities, could produce a long-lasting APV-sensitive membrane depolarization. Also discussed is the possible role of these synaptic potentials in auditory cortical function and plasticity. 相似文献
47.
Brett W. Cox M.D. Kathleen C. Horst M.D. Sherri Thornton C.M.D. Frederick M. Dirbas M.D. 《Medical Dosimetry》2007,32(4):254-262
The purpose of this study was to evaluate the dose to normal tissues as a function of increasing margins around the lumpectomy cavity in accelerated partial breast irradiation (APBI) using 3D-conformal radiotherapy (3DCRT). Eight patients with Stage 0-I breast cancer underwent treatment planning for 3DCRT APBI. The clinical target volume (CTV) was defined as a 15-mm expansion around the cavity limited by the chest wall and skin. Three planning target volumes (PTV1, PTV2, PTV3) were generated for each patient using a 0, 5-, and 10-mm expansion around the CTV, for a total margin of 15, 20, and 25 mm. Three treatment plans were generated for every patient using the 3 PTVs, and dose-volume analysis was performed for each plan. For each 5-mm increase in margin, the mean PTV:total breast volume ratio increased 10% and the relative increase in the mean ipsilateral breast dose was 15%. The mean volume of ipsilateral breast tissue receiving 75%, 50%, and 25% of the prescribed dose increased 6% to 7% for every 5 mm increase in PTV margin. Compared to lesions located in the upper outer quadrant, plans for medially located tumors revealed higher mean ipsilateral breast doses and 20% to 22% more ipsilateral breast tissue encompassed by the 25% IDL. The use of 3DCRT for APBI delivers higher doses to normal breast tissue as the PTV increases around the lumpectomy cavity. Efforts should be made to minimize the overall PTV when this technique is used. Ongoing studies will be necessary to determine the clinical relevance of these findings. 相似文献
48.
49.
R M Thomas A Aldibbiat W Griffin M A A Cox N J Leech J A M Shaw 《Diabetic medicine》2007,24(7):778-783
AIM: To determine potential for amelioration of recurrent severe hypoglycaemia without worsening in overall control in individuals with long-standing Type 1 diabetes (T1DM). METHODS: Twenty-one people with T1DM characterized by altered hypoglycaemia awareness and debilitating severe hypoglycaemia were randomized in a pilot 24-week prospective study to optimized analogue therapy (ANALOGUE; lispro/glargine); continuous subcutaneous insulin infusion therapy (CSII; lispro); or re-education with relaxation of blood glucose targets on existing conventional insulin regimen (EDUCATION). Glycaemic profiles and duration of biochemical hypoglycaemia were measured by continuous subcutaneous glucose monitoring and self-monitored blood glucose. RESULTS: Further severe hypoglycaemia was prevented in five participants (71%) in each group (P = 0.06). Incidence of severe hypoglycaemia was: 0.6 (ANALOGUE), 0.9 (CSII), and 3.7 (EDUCATION) episodes per patient year. Restoration of hypoglycaemia awareness was confirmed by validated questionnaire in three (43%) ANALOGUE, four (57%) CSII and five (71%) EDUCATION patients. Glycated haemoglobin (HbA1c) was significantly improved in the ANALOGUE group between weeks 0 and 24 (8.6 +/- 1.1 vs. 7.6 +/- 0.8%; P = 0.04 for change). Non-significant improvement was seen in the CSII group (8.5 +/- 1.9 vs. 7.4 +/- 1.0%; P = 0.06). No change in HbA1c was seen in the EDUCATION group (8.5 +/- 1.1 vs. 8.3 +/- 1.0%; P = 0.54). There were no episodes of diabetic ketoacidosis or any other adverse events in any group. CONCLUSIONS: In this pilot randomized trial comparing optimized ANALOGUE, CSII or EDUCATION alone in unselected individuals with recurrent severe hypoglycaemia, we show potential for restoring hypoglycaemia awareness and preventing further severe hypoglycaemia with concomitant improvement in glycaemic control in ANALOGUE and CSII groups. 相似文献
50.
Karen Cox 《British journal of nursing (Mark Allen Publishing)》2008,17(13):850-854
The abuse of older people is a significant problem, with estimates intimating that there may be over 340,000 cases per year in the United Kingdom. Despite improvements in screening and assessment to identify and treat those who are abused or at risk of abuse, the healthcare community remains preoccupied with prevalence rather than prevention. In light of the paucity of health-related research evidence to support the effectiveness of preventative measures, the application of crime prevention theory and knowledge is appropriate. Routine activity theory and situational crime prevention literature acknowledges the vulnerability of older people to abuse and the potential of any person employed as a carer to be an abuser. Preventative measures are focused on techniques that make abuse more difficult and more risky for the perpetrator and, therefore, less 'rewarding'. The regulation of healthcare support workers and increased workplace surveillance are examples of the 25 techniques of situational prevention that could be applied in a healthcare setting. 相似文献