全文获取类型
收费全文 | 2475篇 |
免费 | 139篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 30篇 |
儿科学 | 110篇 |
妇产科学 | 39篇 |
基础医学 | 326篇 |
口腔科学 | 101篇 |
临床医学 | 242篇 |
内科学 | 490篇 |
皮肤病学 | 132篇 |
神经病学 | 103篇 |
特种医学 | 304篇 |
外科学 | 230篇 |
综合类 | 37篇 |
预防医学 | 224篇 |
眼科学 | 61篇 |
药学 | 93篇 |
中国医学 | 4篇 |
肿瘤学 | 121篇 |
出版年
2021年 | 28篇 |
2019年 | 25篇 |
2018年 | 24篇 |
2017年 | 23篇 |
2016年 | 32篇 |
2015年 | 44篇 |
2014年 | 54篇 |
2013年 | 87篇 |
2012年 | 63篇 |
2011年 | 62篇 |
2010年 | 72篇 |
2009年 | 79篇 |
2008年 | 67篇 |
2007年 | 86篇 |
2006年 | 72篇 |
2005年 | 63篇 |
2004年 | 57篇 |
2003年 | 49篇 |
2002年 | 57篇 |
2001年 | 53篇 |
2000年 | 50篇 |
1999年 | 44篇 |
1998年 | 96篇 |
1997年 | 79篇 |
1996年 | 93篇 |
1995年 | 65篇 |
1994年 | 71篇 |
1993年 | 65篇 |
1992年 | 58篇 |
1991年 | 38篇 |
1990年 | 46篇 |
1989年 | 68篇 |
1988年 | 74篇 |
1987年 | 64篇 |
1986年 | 57篇 |
1985年 | 59篇 |
1984年 | 43篇 |
1983年 | 27篇 |
1982年 | 35篇 |
1981年 | 26篇 |
1980年 | 16篇 |
1979年 | 28篇 |
1978年 | 18篇 |
1977年 | 22篇 |
1976年 | 22篇 |
1975年 | 21篇 |
1974年 | 15篇 |
1973年 | 21篇 |
1972年 | 16篇 |
1971年 | 13篇 |
排序方式: 共有2647条查询结果,搜索用时 15 毫秒
71.
72.
B. H. Sullivan Jr. COL. MC U. S. ARMY Nelson S. Irey LT. COL. MC U. S. ARMY Vincent J. Pileggi ST LT. MSC U. S. ARMY Richard I. Crone COL. MC U. S. ARMY John R. Gibson LT. COL. MC U. S. ARMY 《Digestive diseases and sciences》1957,2(4):210-223
Summary 1. Twenty-two patients with infectious mononucleosis were studied by liver biopsy and paper electrophoresis of the serum proteins. The findings were compared with a similar group of 30 patients with infectious hepatitis.2. The essential histologic features of infectious mononucleosis were the presence in the hepatic sinusoids and portal tracts of chronic inflammatory cells resembling small lymphocytes, with essentially no parenchymal cell damage. Admixed with this lymphocytic infiltrate, but in relatively minimal numbers, were a few plasma cells and polymorphonuclear leukocytes. In addition, in infectious mononucleosis there were, with rare exceptions, no lipochrome-containing Kupffer cells. Thus, in the majority of cases, the histologic picture was distinct from that seen in infectious hepatitis. Only in comparing a few of the more severe infectious mononucleosis cases with subsiding infectious hepatitis cases was there any tendency for the two pictures to merge, and the distinction on histologic grounds between the two entities could be made in the great majority of cases.3. The most commonly seen abnormalities in the paper electrophoretic patterns of sera obtained from patients with infectious mononucleosis were decreased albumin, increased gamma globulin, not infrequent but variable changes in alpha2 globulin, and the presence of abnormal proteins migrating with mobilities intermediate to alpha2 and beta, and beta and gamma globulins. The abnormalities observed in infectious hepatitis were similar to those of infectious mononucleosis, except that in hepatitis alpha2 globulin was decreased more consistently, gamma globulin increased less frequently, and beta globulin, which was normal in practically all the cases of infectious mononucleosis, was increased in a considerable number of cases.4. Treatment of patients with infectious mononucleosis need not include prolonged bed rest and restriction of activity in an effort to avoid the development of chronic liver disease. 相似文献
73.
P. H. Sebrechts CAPT MC USN J. P. Anderson Jr. LCDR MC USN 《Diseases of the colon and rectum》1971,14(1):57-61
Summary The management of pilonidal cyst disease in a large military hospital is described. Of special interest to the military practice
is the “buddy” system, in which patients help one another to keep their wounds clean and dry. The specific objectives of our
technic are: 1) obtaining excellent hemostasis by the use of zinc peroxide paste; 2) avoiding recurrences by an open-wound
method of treatment; 3) preservation of a pad of subcutaneous tissue over the postsacral fascia, thus reducing long-term morbidity
by insuring a mobile scar; 4) decreasing the duration of hospitalization, achieved by frequently drying the wounds with warm
air.
Read at the meeting of the American Proctologic Society, Hollywood, Florida, April 12 to 16, 1970.
The opinions or assertions contained herein are those of the authors and are not to be construed as official or as reflecting
the views of the Navy Department. 相似文献
74.
Temperature plays a significant role in the vector competence, extrinsic incubation period, and intensity of infection of arboviruses within mosquito vectors. Most laboratory infection studies use static incubation temperatures that may not accurately reflect daily temperature ranges (DTR) to which mosquitoes are exposed. This could potentially compromise the application of results to real world scenarios. We evaluated the effect of fluctuating DTR versus static temperature treatments on the infection, dissemination, and transmission rates and viral titers of Culex tarsalis and Culex quinquefasciatus mosquitoes for West Nile virus. Two DTR regimens were tested including an 11 and 15 °C range, both fluctuating around an average temperature of 28 °C. Overall, no significant differences were found between DTR and static treatments for infection, dissemination, or transmission rates for either species. However, significant treatment differences were identified for both Cx. tarsalis and Cx. quinquefasciatus viral titers. These effects were species-specific and most prominent later in the infection. These results indicate that future studies on WNV infections in Culex mosquitoes should consider employing realistic DTRs to reflect interactions most accurately between the virus, vector, and environment. 相似文献
75.
76.
77.
LN Barlow-Mosha DS Bagenda PK Mudiope MC Mubiru LM Butler MG Fowler PM Musoke 《African health sciences》2012,12(3):249-258
Background
Access to pediatric antiretroviral formulations is increasing in resource-limited countries, however adult FDCs are still commonly used by antiretroviral therapy (ART) programs.Objective
To describe long-term effectiveness of using adult FDC of d4T+3TC+NVP (Triomune) in children for HIV treatment.Methods
Clinical, immunologic, and virologic outcomes of HIV-infected ART-naïve children aged six months to 12 years, were evaluated up to 96 weeks post-ART initiation.Results
From March 2004 to June 2006, 104 children were followed with a median age of 5.4 years, median CD4 cell percent and HIV-1 RNA were 11.0% (IQR 6.7–13.9) and 348,846copies/mL (IQR 160,941–681,313) respectively at baseline. Using Kaplan-Meir estimates, 75% of children had undetectable viral loads (<400copies/mL) at 96weeks of ART. Children with a baseline CD4 cell percent >15% were 3 times more likely to achieve viral load <400copies/mL than those with baseline CD4 cell percent <5% after adjusting for baseline age {aHR = 3.03 (1.10–8.32), p=0.03}; no difference was found among those with CD4 cell percent >5–14.9% and <5%.Conclusion
Treatment with generic adult FDC for HIV-infected Ugandan children led to sustained clinical, immunologic and virologic response during 96 weeks of ART. Early initiation of ART is key to achieving virological success. 相似文献78.
AMJ van Wegberg RAF Evers JGM Burgerhof E van Dam M.R. Heiner-Fokkema MCH Janssen MC de Vries FJ van Spronsen 《Molecular genetics and metabolism》2021,132(1):49-55
BackgroundIn patients with phenylketonuria, stability of blood phenylalanine and tyrosine concentrations might influence brain chemistry and therefore patient outcome. This study prospectively investigated the effects of tetrahydrobiopterin (BH4), as a chaperone of phenylalanine hydroxylase on diurnal and day-to-day variations of blood phenylalanine and tyrosine concentrations.MethodsBlood phenylalanine and tyrosine were measured in dried blood spots (DBS) four times daily for 2 days (fasting, before lunch, before dinner, evening) and once daily (fasting) for 6 days in a randomized cross-over design with a period with BH4 and a period without BH4. The sequence was randomized. Eleven proven BH4 responsive PKU patients participated, 5 of them used protein substitutes during BH4 treatment. Natural protein intake and protein substitute dosing was adjusted during the period without BH4 in order to keep DBS phenylalanine levels within target range. Patients filled out a 3-day food diary during both study periods. Variations of DBS phenylalanine and Tyr were expressed in standard deviations (SD) and coefficient of variation (CV).ResultsBH4 treatment did not significantly influence day-to-day phenylalanine and tyrosine variations nor diurnal phenylalanine variations, but decreased diurnal tyrosine variations (median SD 17.6 μmol/l, median CV 21.3%, p = 0.01) compared to diet only (median SD 34.2 μmol/l, median CV 43.2%). Consequently, during BH4 treatment diurnal phenylalanine/tyrosine ratio variation was smaller, while fasting tyrosine levels tended to be higher.ConclusionBH4 did not impact phenylalanine variation but decreased diurnal tyrosine and phenylalanine/tyrosine ratio variations, possibly explained by less use of protein substitute and increased tyrosine synthesis. 相似文献
79.
80.
Dr. Töres Theorell M.D. Dr. Richard H. Rahe MC USNR 《Behavioral medicine (Washington, D.C.)》2013,39(3):18-24
Abstract Thirty-six men and women who experienced a documented myocardial infarction, half of whom ultimately died from their disease and half of whom survived over a six-year period, provided longitudinal recent life changes and ballistocardiographic data. The 18 patients who died from their coronary disease indicated a significant buildup in life changes which peaked approximately one year prior to death; their serial ballistocardiograms indicated a significant buildup in average force of contraction which was seen to peak approximately six months prior to death. The 18 post-infarction patients who survived the six-year follow-up showed neither a buildup in life change nor a buildup in the ballistocardiographic index of cardiac contraction force. These findings of a life change peak preceding ballistocardiographic evidence of an “overworked” heart are discussed in terms of their possible medical and psychophysiological significances. 相似文献