全文获取类型
收费全文 | 1491898篇 |
免费 | 96870篇 |
国内免费 | 3318篇 |
专业分类
耳鼻咽喉 | 21889篇 |
儿科学 | 46051篇 |
妇产科学 | 43378篇 |
基础医学 | 207573篇 |
口腔科学 | 44616篇 |
临床医学 | 124835篇 |
内科学 | 289459篇 |
皮肤病学 | 33700篇 |
神经病学 | 115347篇 |
特种医学 | 62398篇 |
外国民族医学 | 517篇 |
外科学 | 231654篇 |
综合类 | 31988篇 |
现状与发展 | 6篇 |
一般理论 | 437篇 |
预防医学 | 106014篇 |
眼科学 | 34951篇 |
药学 | 110508篇 |
6篇 | |
中国医学 | 3110篇 |
肿瘤学 | 83649篇 |
出版年
2018年 | 14931篇 |
2017年 | 13114篇 |
2016年 | 13444篇 |
2015年 | 16230篇 |
2014年 | 20449篇 |
2013年 | 28125篇 |
2012年 | 41459篇 |
2011年 | 38793篇 |
2010年 | 22560篇 |
2009年 | 23511篇 |
2008年 | 35205篇 |
2007年 | 38915篇 |
2006年 | 39694篇 |
2005年 | 45970篇 |
2004年 | 46473篇 |
2003年 | 41316篇 |
2002年 | 36360篇 |
2001年 | 66459篇 |
2000年 | 66437篇 |
1999年 | 59221篇 |
1998年 | 15035篇 |
1997年 | 13638篇 |
1996年 | 13174篇 |
1995年 | 12463篇 |
1992年 | 47565篇 |
1991年 | 46372篇 |
1990年 | 45867篇 |
1989年 | 44624篇 |
1988年 | 41639篇 |
1987年 | 41054篇 |
1986年 | 39304篇 |
1985年 | 36989篇 |
1984年 | 27515篇 |
1983年 | 23213篇 |
1982年 | 13407篇 |
1981年 | 12150篇 |
1979年 | 26820篇 |
1978年 | 18862篇 |
1977年 | 16153篇 |
1976年 | 14614篇 |
1975年 | 17167篇 |
1974年 | 20547篇 |
1973年 | 19747篇 |
1972年 | 18953篇 |
1971年 | 17967篇 |
1970年 | 17001篇 |
1969年 | 16360篇 |
1968年 | 15328篇 |
1967年 | 13835篇 |
1966年 | 12888篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
Lázaro Alessandro S Nunes Paulo Guimar?es Gandra Armindo Antonio Alves Lauro T Kubota Denise Vaz de Macedo 《Clinical journal of sport medicine》2006,16(5):418-421
OBJECTIVE: The authors tested the effect of blood sampling (skin versus venous puncture) on some biochemical and hematological blood parameters in athletes to answer whether skin puncture could be used as a substitute for venous puncture. DESIGN: Comparative study of 2 methods of blood samples collection. SETTING: The blood was collected in the same athletes at 3 different moments of the preparatory training phase. PARTICIPANTS: Fourteen male indoor soccer players (22 +/- 1 years old) and 7 female handball players (18 +/- 1 years old) participated. MAIN OUTCOME MEASUREMENT: Blood was collected in heparin and K3EDTA by Vacutainer BD or Microvette Sarstedt system for biochemical and hematological analyses, respectively. RESULTS: There were no significant statistical differences between the 2 methods for the values of creatine kinase, urea, creatinine, lymphocytes, and platelets. The other hematological analyzes and uric acid exhibited significant higher values in skin blood, although they were all within the normal expected range. A high degree of correlation was observed between the 2 techniques for all parameters. CONCLUSIONS: Skin puncture is a reliable, easy, accurate, and less invasive sampling method for assessing hematological and some biochemical parameters in athletes, respecting that blood samples should always be obtained from the same site, especially in follow-up studies. 相似文献
972.
973.
974.
975.
976.
Francisco Sampaio Pedro Mateus Nuno Bettencourt Carla Costa Dias Luís Ad?o Lino Santos Madalena Teixeira Lino Sim?es Vasco Gama 《Revista portuguesa de cardiologia》2006,25(3):321-327
INTRODUCTION: Ischemic heart disease is a major cause of heart failure in western societies. However, the factors that may influence left ventricular function (LVF) recovery after an acute coronary syndrome (ACS) are still unclear. OBJECTIVE: To identify variables that may influence LVF evolution one year after ACS. METHODS: 104 patients hospitalized with ACS between 7/1/2001 and 12/31/2002 and with systolic dysfunction--defined as an echocardiographic ejection fraction (EF) < or = 45%--were randomly allocated to a planned coronary follow-up program (FUP) or a general cardiology clinic (GC); patients from both groups were also randomly referred to a structured cardiac rehabilitation program (CRP). EF was re-assessed at one year. We compared differences between patients who recovered left ventricular function (EF > 45%; group 1) and those who did not (group 2). RESULTS: One year after discharge, 44.2% of the patients had recovered function. There were no significant differences between the groups in gender (77.7 vs. 76.5% male), age (56 vs. 59 years), hypertension, diabetes, dyslipidemia, smoking habits or family history. A previous history of cardiovascular events was more frequent in group 2 (11.1% vs. 35.3%, p = 0.03). Cardiac catheterization was performed before discharge in 88.8% and 88.2% in groups 1 and 2 respectively (p = NS); no differences were found in coronary anatomy between the two groups. Angioplasty was performed in 54.2% in group 1 and 50% in group 2 (p = NS). There were no differences in the use of angiotensin-converting enzyme inhibitors (83.3% vs. 87.5%), beta-blockers (87.5% vs. 87.5%), nitrates (37.5% vs. 33.3%), aspirin (95.8% vs. 95.8%), statins (79.1% vs. 75%) or diuretics (20.8% vs. 45.8%). There was no significant difference in LVF recovery between patients randomized to FUP or GC (38.5% vs. 54.5%). 87.5% of patients who completed the CRP had normal EF at one year compared to 32.7% of patients not referred to the program (p = 0.009). Although EF improved in both groups, this improvement was greater in patients who completed a CRP (EF 8% vs. 5%, p = 0.003). CONCLUSION: A previous cardiovascular event and completion of a CRP were the only variables that influenced LVF recovery. Thus, enrollment in a CRP, in addition to standard therapy, could be an important therapeutic measure in patients with systolic dysfunction after ACS; our data suggest that these programs should be more widely used. 相似文献
977.
A. Beamonte F. Goldfain-Blanc N. Casadevall D. Bazot H. Bertheux N. Claude 《Comparative clinical pathology》2005,14(1):61-65
As part of the early preclinical development of a new antipsychotic compound, Wistar rats of both sexes were dosed orally for upto 7 days. At high doses, expected changes in appearance and behavior, decreases in bodyweight gain and feed intake but also a fluid and pale bone marrow (BM) were observed. Blood cell counts were normal as were clinical chemical values. BM sections showed a red cell hypoplasia. Circulating reticulocytes and erythroblasts on BM smears were decreased suggesting that the compound might have a selective toxicity for the erythroid lineage. In a mechanistic experiment, rats were dosed for 9 days and phlebotomized after 7 days of exposure to stimulate erythroid regeneration. Red-blood cell mass, reticulocytes and erythropoietin (EPO) levels were monitored before and upto 48 h after bleeding. Results showed that an EPO-mediated pathogenesis could be excluded. The effect of the drug on the formation of Colony-forming units (CFU)-E and CFU-GM was then quantitatively measured in vitro after direct exposure to the compound. In two successive assays, rat or human BM cells were incubated with the drug dissolved in the collection medium at final concentrations of 0.3×10–7 –3×10–5 M. In the presence of adequate growth factors, CFU-E and CFU-GM were cultured and cell proliferation was compared between treated and control groups. Our results showed an expected inhibition by the drug of the growth of erythroid progenitors associated to a similar effect on myeloid progenitors. The CFU-E and CFU-GM of both human and rat sources were totally inhibited from the concentration of 3×10–5 M. The IC50 values were consistent with rat peak plasma levels reached in vivo by the drug. Therefore, the short-term cloning assays performed on rat BM cells were sensitive indicators of the hematotoxicity of the compound and were considered as predictive for human toxicity. 相似文献
978.
979.
Effects of halothane on spinal dorsal horn WDR(wide dynamic range) neuronal activity in cats 总被引:1,自引:0,他引:1
H Nagasaka S Nakamura T Genda T Miyazaki K Aikawa N Matsumoto I Matsumoto T Hori I Sato 《Masui. The Japanese journal of anesthesiology》1991,40(7):1096-1101
The effects of halothane (0.2%, 0.5%, and 1.0%) on the spinal dorsal horn wide dynamic range (WDR) neuronal activity was studied in either spinal cord intact or spinal transected cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left hind foot pads of intact or decerebrate, spinal cord transected (L 1-2) cats. When 10 micrograms of bradykinin was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus in the spinal cat, all of 7 WDR neurons gave excitatory responses which were not depressed by 0.2% and 0.5% halothane but were depressed significantly by 1.0%. On the other hand, when the injection of 10 micrograms of bradykinin into the femoral artery ipsilateral to the recording site was used in the intact cat, 7 of 14 WDR neurons (50%) gave excitatory responses, which were not depressed by 0.2% halothane but were significantly depressed by 0.5% and 1.0% halothane, and 7 of 14 WDR neurons (50%) gave inhibitory responses, which were significantly depressed by 0.2%, 0.5%, and 1.0% halothane. We have found that halothane reduces the excitation as well as the inhibition of dorsal horn WDR neuronal activity induced by bradykinin injection. 相似文献
980.
Conditions that affect the dentition and the materials utilized to treat these conditions are often unfamiliar to the physician. Dental caries and missing teeth are processes routinely treated in dental practice. Recent improvements in dental materials and techniques permit the dentist to restore the dentition to allow for corrected form, function, esthetics, and patient comfort. This paper describes some of the common conditions that affect the dentition, and the modalities routinely used to treat them. 相似文献