全文获取类型
收费全文 | 31364篇 |
免费 | 1921篇 |
国内免费 | 158篇 |
专业分类
耳鼻咽喉 | 268篇 |
儿科学 | 503篇 |
妇产科学 | 312篇 |
基础医学 | 4622篇 |
口腔科学 | 931篇 |
临床医学 | 3042篇 |
内科学 | 7518篇 |
皮肤病学 | 460篇 |
神经病学 | 3510篇 |
特种医学 | 1862篇 |
外科学 | 4196篇 |
综合类 | 178篇 |
一般理论 | 11篇 |
预防医学 | 1306篇 |
眼科学 | 606篇 |
药学 | 1809篇 |
中国医学 | 52篇 |
肿瘤学 | 2257篇 |
出版年
2024年 | 28篇 |
2023年 | 268篇 |
2022年 | 439篇 |
2021年 | 826篇 |
2020年 | 514篇 |
2019年 | 714篇 |
2018年 | 798篇 |
2017年 | 617篇 |
2016年 | 880篇 |
2015年 | 998篇 |
2014年 | 1261篇 |
2013年 | 1556篇 |
2012年 | 2527篇 |
2011年 | 2526篇 |
2010年 | 1515篇 |
2009年 | 1359篇 |
2008年 | 2225篇 |
2007年 | 2238篇 |
2006年 | 2162篇 |
2005年 | 2033篇 |
2004年 | 1755篇 |
2003年 | 1673篇 |
2002年 | 1564篇 |
2001年 | 286篇 |
2000年 | 223篇 |
1999年 | 293篇 |
1998年 | 313篇 |
1997年 | 230篇 |
1996年 | 173篇 |
1995年 | 163篇 |
1994年 | 128篇 |
1993年 | 95篇 |
1992年 | 70篇 |
1991年 | 63篇 |
1990年 | 44篇 |
1989年 | 61篇 |
1988年 | 39篇 |
1987年 | 33篇 |
1986年 | 36篇 |
1985年 | 35篇 |
1984年 | 31篇 |
1983年 | 39篇 |
1982年 | 35篇 |
1981年 | 31篇 |
1980年 | 33篇 |
1975年 | 26篇 |
1974年 | 25篇 |
1937年 | 31篇 |
1936年 | 25篇 |
1935年 | 35篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Olle Zetterström Christer Andersson Leif Eriksson ers Fredriksson Johan Friskopp Gunnar Heden Bernt Jansson Tord Lundgren Rolf Nilveus ers Olsson Stefan Renvert Lars Salonen Lars Sjöström ers Winell ers Östgren Stina Gestrelius 《Journal of clinical periodontology》1997,24(9):697-704
Abstract The aim of the present clinical trial was to test tolerability during 2 treatments with EMDOGAIN® in a large number of patients. An open, controlled study design in 10 Swedish specialist clinics was chosen, with a test group of 107 patients treated with EMDOGAIN® in connection with periodontal surgery at 2 surgical test sites per patient. The procedures were performed 2 to 6 weeks apart on one-rooted teeth with at least 4 mm deep intraosseous lesions. A control group of 33 patients underwent flap surgery without EMDOGAIN® at I comparable site. In total 214 test and 33 control surgeries were performed. Serum samples were obtained from test patients for analysis of total and specific antibody levels. 10 of the patients had samples taken before and after the first surgery. 56 other samples were taken after one treatment with EMDOGAIN®, and 63 after 2 treatments. None of the samples, not even from allergy-prone patients after 2 treatments, indicated deviations from established baseline ranges. This indicates that the immunogenic potential of EMDOGAIN® is extremely low when applied in conjunction with periodontal surgery. Comparison between the test and control groups demonstrated the same type and frequency of post-surgical experiences, i.e., reactions caused by the surgical procedure itself. Clinical probing and radiographic evaluation was performed at baseline and 8 months postsurgery. About half of the patients (44 test and 21 control) were also evaluated after 3 years. There was a significant difference between the test and control results at 8 months post surgery. and this difference had increased further at the 3 year follow-up. The 2.5–3 mm increase in attachment and bone level after treatment with EMDOGAIN® was of the same magnitude as seen in the studies with split-mouth design aiming for lest of effectiveness of EMDOGAIN®. 相似文献
12.
Cytokines as therapeutic drugs. 总被引:1,自引:0,他引:1
Cytokines are a growing group of proteins that are responsible for the communication of cells of the immune system, hematopoietic cells, and other cell types. They play a dominant role in various diseases, particularly in promoting and perpetuating inflammation. Cytokine production is a reaction of the body to a pathologic state to restore homeostasis. In such cases, the therapeutic intervention should support the reaction of the body by giving the cytokine itself (agonistic therapeutics). In other cases, manifestation of a disease results from an overproduction of cytokines, making cytokine antagonists desirable therapeutic drugs. Furthermore, cytokines may be good candidates as cancer therapeutics, especially to support the restoration of blood cell populations after chemotherapy or radiation. 相似文献
13.
Galanin-like immunoreactivity has been visualized in nerve fibers in the islets of Langerhans, suggesting an involvement of
galanin in the neural regulation of islet function. In this study, we investigated the effects of galanin on basal and stimulated
insulin and glucagon secretion by infusing the peptide at three different dose rates in rats. We also studied the direct effect
of galanin on insulin secretion from freshly isolated rat islets. At 320 pmol/kg/min, but not at 20 or 80 pmol/kg/min, galanin
lowered basal plasma insulin levels. In contrast, basal plasma glucagon levels were lowered by galanin already at 20 and 80
pmol/kg/min. Furthermore, galanin inhibited both glucose- and arginine-induced insulin release at all three dose levels, whereas
arginine-induced glucagon release was not affected by galanin. Glucose-stimulated insulin secretion from isolated rat islets
was dose-dependently suppressed by galanin (10-6-10-8M). Therefore, it is concluded that galanin in rats inhibits insulin secretion, both in vivo and in vitro, and that at lower
dose levels, the peptide also inhibits basal glucagon release. 相似文献
14.
15.
Andreas Lange Claudia Kistler Tanja B. Jutzi Alexandr V. Bazhin Claus Detlev Klemke Dirk Schadendorf Stefan B. Eichmüller 《Experimental dermatology》2009,18(6):527-535
Abstract: The identification of tumor-specific proteins located at the plasma membrane is hampered by numerous methodological pitfalls many of which are associated with the post-translational modification of such proteins. Here, we present a new combination of detergent fractionation of cells and of subtractive suppression hybridization (SSH) to gain overexpressed genes coding for membrane-associated or secreted proteins. Fractionation of subcellular components by digitonin allowed sequestering mRNA of the rough Endoplasmatic reticulum and thereby increasing the percentage of sequences coding for membrane-bound proteins. Fractionated mRNAs from the cutaneous T-cell lymphoma (CTCL) cell line HuT78 and from normal peripheral blood monocytes were used for SSH leading to the enrichment of sequences overexpressed in the tumor cells. We identified some 21 overexpressed genes, among them are GPR137B, FAM62A, NOMO1, HSP90, SLIT1, IBP2, CLIF, IRAK and ARC. mRNA expression was tested for selected genes in CTCL cell lines, skin specimens and peripheral blood samples from CTCL patients and healthy donors. Several of the detected sequences are clearly related to cancer, but have not yet been associated with CTCL. qPCR confirmed an enrichment of these mRNAs in the rough endoplasmic reticulum fraction. RT-PCR confirmed the expression of these genes in skin specimens and peripheral blood of CTCL patients. Western blotting verified protein expression of HSP90 and IBP2 in HuT78. GPR137B could be detected by immunohistology in HuT78 and in keratinocytes of dysplastic epidermis, but also in sweat glands of healthy skin. In summary, we developed a new technique, which allows identifying overexpressed genes coding preferentially for membrane-associated proteins. 相似文献
16.
Walter S Speidl Markus Exner Jasmin Amighi Wolfgang Mlekusch Schila Sabeti Stefan P Kastl Gerlinde Zorn Gerald Maurer Oswald Wagner Kurt Huber Erich Minar Johann Wojta Martin Schillinger 《Journal of endovascular therapy》2007,14(1):62-69
PURPOSE: To investigate whether balloon angioplasty of the superficial femoral artery (SFA) increases serum levels of C5a and whether C5a predicts risk of restenosis. METHODS: C5a antigen was measured at baseline and 8 hours after intervention in 131 consecutive patients (76 women; median age 72 years) with intermittent claudication who underwent successful primary SFA balloon angioplasty. Patients were followed for a median 10 months [interquartile range (IQR) 6 to 14] for the occurrence of >50% restenosis by duplex ultrasound. RESULTS: Median C5a levels increased significantly from 39.7 ng/mL (IQR 27.8 to 55.0) at baseline to 53.8 ng/mL (IQR 35.6 to 85.1, p<0.001) 8 hours post intervention. During the follow-up period, 70 (53%) patients developed restenosis. Increasing levels of C5a (quartiles) at baseline were significantly associated with an increased risk for restenosis (p=0.0092). Adjusted hazard ratios (95% confidence intervals) for restenosis with increasing quartiles of baseline serum C5a levels were 1.24 (0.60 to 2.58), 1.93 (0.95 to 3.93), and 2.08 (1.02 to 4.21), respectively, compared to the lowest quartile. This effect was independent of nonspecific inflammation as reflected by plasma levels of C-reactive protein. CONCLUSION: Inflammatory mechanisms play a major role in the development of restenosis after angioplasty. The complement component C5a exerts strong chemotactic and proinflammatory effects. Enhanced complement activation prior to PTA, as measured by higher levels of C5a, was significantly associated with restenosis after SFA balloon angioplasty. Pathways of complement inhibition thus may be worth investigating with respect to improving patency rates. 相似文献
17.
18.
19.
Stefan Ockert Hardy Schumacher Dittmar Böckler Katrin Malcherek Jochen Hansmann Jens Allenberg 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):725-730
Background and aims Since the introduction of endovascular aortic aneurysm repair (EVAR) for aortic aneurysms, the number of juxtarenal aortic
aneurysms (JRA) has been growing steadily due to selection bias (neck morphology for EVAR). This case-match study compares
the perioperative outcome and midterm results of suprarenally clamped JRA with infrarenal aortic aneurysms (AAA).
Methods From 1997 to 2004, patients who received open surgery with suprarenal clamping for JRA were included in the study and compared
to matched patients with infrarenal clamping (AAA). Measurements analyzed were the in-hospital mortality and morbidity. Midterm
results were obtained through clinical investigation and magnetic resonance angiography imaging.
Results Thirty-five patients (mean age, 68.4 years; 30 male and 5 female) received suprarenal cross-clamping for JRA. The overall
in-hospital mortality for JRA and for the controls (AAA) with elective aortic repair was 4.5% (6.1% JRA; 3% AAA, p = 0.058). The morbidity of JRA was elevated according to the rate of pulmonary complications (p = 0.021) and the need for re-operation (p = 0.019). The mean follow-up time was 2.3 years (range, 8–96 months). At follow-up, 28 patients (80%) from the JRA group
and 29 patients from the AAA group (82.9%) were alive.
Conclusion Open aortic surgery for JRA with the need for suprarenal cross-clamping shows a slightly elevated in-hospital mortality rate
without statistical significance and equal midterm mortality results in comparison with infrarenally clamped aortic aneurysms. 相似文献
20.
Werner Benzer Marion Platter Neil B Oldridge Helmut Schwann Kurt Machreich Werner Kullich Karl Mayr Axel Philippi Alfred Gassner Jakob D?rler Stefan H?fer 《European journal of cardiovascular prevention and rehabilitation》2007,14(3):441-447
BACKGROUND: An objective of exercise-based cardiac rehabilitation is improvement in patient-reported outcomes such as health-related quality of life as well as anxiety and depressive symptoms. There are no direct comparisons of the effectiveness of inpatient and outpatient exercise-based cardiac rehabilitation programmes on patient-reported outcomes. METHODS: In this non-randomized study we collected patient-reported outcomes data with the MacNew Heart Disease health-related quality of life questionnaire and the Hospital Anxiety and Depression Scale at baseline, 1 month and again 3 months after admission to exercise-based cardiac rehabilitation in a cohort of 216 consecutive patients enrolled either in a 4-week inpatient exercise-based cardiac rehabilitation (n=62) or a 3-month outpatient exercise-based cardiac rehabilitation (n=87) and in a usual care group (n=67) to document the natural course in patient-reported outcome variables without exercise-based cardiac rehabilitation. RESULTS: Although MacNew health-related quality of life scores improved more with inpatient than outpatient exercise-based cardiac rehabilitation by month 1, the improvement was still significant in both groups at month 3 and also in the usual care group when compared to baseline. The health-related quality of life scores in the inpatient group, however, decreased between month 1 and 3 whereas they continued to improve in the outpatient group. The significant reduction in both anxiety and depressive symptoms in both exercise-based cardiac rehabilitation groups by month 1 was maintained at month 3 only with outpatient exercise-based cardiac rehabilitation. No significant changes over the 3 months were observed in the usual care group. CONCLUSION: Significant improvements of 1-month patient-reported outcomes are achieved in patients attending inpatient as well as outpatient exercise-based cardiac rehabilitation when compared with no exercise-based cardiac rehabilitation. In contrast to inpatient exercise-based cardiac rehabilitation, however, outpatient exercise-based cardiac rehabilitation leads to a further improvement of patient-reported outcomes. These results suggest that, if patients have to be admitted for inpatient exercise-based cardiac rehabilitation, this programme should be followed by an outpatient exercise-based cardiac rehabilitation to further improve and stabilize these patient-reported outcome variables. 相似文献