全文获取类型
收费全文 | 6499篇 |
免费 | 492篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 38篇 |
儿科学 | 130篇 |
妇产科学 | 182篇 |
基础医学 | 1124篇 |
口腔科学 | 117篇 |
临床医学 | 636篇 |
内科学 | 1193篇 |
皮肤病学 | 189篇 |
神经病学 | 866篇 |
特种医学 | 224篇 |
外科学 | 568篇 |
综合类 | 59篇 |
一般理论 | 8篇 |
预防医学 | 492篇 |
眼科学 | 347篇 |
药学 | 327篇 |
中国医学 | 9篇 |
肿瘤学 | 491篇 |
出版年
2024年 | 21篇 |
2023年 | 109篇 |
2022年 | 175篇 |
2021年 | 269篇 |
2020年 | 183篇 |
2019年 | 238篇 |
2018年 | 265篇 |
2017年 | 209篇 |
2016年 | 276篇 |
2015年 | 280篇 |
2014年 | 314篇 |
2013年 | 356篇 |
2012年 | 566篇 |
2011年 | 538篇 |
2010年 | 269篇 |
2009年 | 253篇 |
2008年 | 376篇 |
2007年 | 318篇 |
2006年 | 341篇 |
2005年 | 293篇 |
2004年 | 211篇 |
2003年 | 222篇 |
2002年 | 165篇 |
2001年 | 42篇 |
2000年 | 45篇 |
1999年 | 44篇 |
1998年 | 33篇 |
1997年 | 32篇 |
1996年 | 23篇 |
1995年 | 20篇 |
1994年 | 15篇 |
1993年 | 18篇 |
1992年 | 38篇 |
1991年 | 41篇 |
1990年 | 29篇 |
1989年 | 28篇 |
1988年 | 34篇 |
1987年 | 25篇 |
1986年 | 37篇 |
1985年 | 28篇 |
1984年 | 34篇 |
1983年 | 26篇 |
1982年 | 15篇 |
1981年 | 12篇 |
1980年 | 12篇 |
1979年 | 16篇 |
1978年 | 12篇 |
1977年 | 13篇 |
1976年 | 10篇 |
1973年 | 7篇 |
排序方式: 共有7000条查询结果,搜索用时 15 毫秒
1.
2.
3.
The association between family affluence and smoking among 15‐year‐old adolescents in 33 European countries,Israel and Canada: the role of national wealth 下载免费PDF全文
4.
Tobias Kisch Julia Maria Klemens Katharina Hofmann Eirini Liodaki Matthias Gierloff Dirk Moellmeier Felix Stang Peter Mailaender Jens Habermann Matthias Brandenburger 《Medicine》2015,94(41)
The regrowth of amputated digit tips represents a unique regenerative healing in mammals with subcutaneous volume regrowth, restoration of dactylogram, and suppression of scar formation. Although factor analysis in amphibians and even in mice is easy to obtain, safety of harvesting biomaterial from human digit tip amputations for analysis has not yet been described.The aim of this study was to evaluate if recovering wound exudate does hamper clinical outcome or influence microbiologic or inflammation status.A predefined cohort of 18 patients with fresh digit tip amputations was randomly assigned to receive standard therapy (debridement, occlusive dressing) with (n = 9) or without (n = 9) collection of the whole wound exudate in every dressing change. Primary endpoint (lengthening) and secondary endpoints (regeneration of dactylogram, nail bed and bone healing, time to complete wound closure, scar formation, 2-point discrimination, microbiologic analysis, inflammatory factors interleukin (IL)-1α, tumor necrosis factor-α, IL-4, and IL-6) were determined by an independent, blinded observer.Patients’ characteristics showed no significant differences between the groups. All patients completed the study to the end of 3 months follow-up. Exudate collection did not influence primary and secondary endpoints. Furthermore, positive microbiologic findings as well as pus- and necrosis-like appearance neither impaired tissue restoration nor influenced inflammatory factor release.Here, the authors developed an easy and safe protocol for harvesting wound exudate from human digit tip amputations. For the first time, it was shown that harvesting does not impair regenerative healing. Using this method, further studies can be conducted to analyze regeneration associated factors in the human digit tip.DRKS.de Identifier: DRKS00006882 (UTN: U1111-1166-5723). 相似文献
5.
Christiana Winkler Barbara Frick Katharina Schroecksnadel Harald Schennach Dietmar Fuchs 《Food and chemical toxicology》2006,44(12):2003-2007
Antioxidant preservatives prolong the quality of food and ensure the nutritional adequacy, palatability and safety of many processed foods and beverages. Effects of sodium sulfite (E221) and sorbic acid (E200) were investigated in human peripheral blood mononuclear cells (PBMC) which were purified from blood of healthy donors. Cells were stimulated with the mitogen phytohaemagglutinin in vitro, which induces proliferation of T-cells and the production of Th1-type cytokines like interferon-γ. The latter triggers enzyme indoleamine (2,3)-dioxygenase, which degrades tryptophan, and GTP cyclohydrolase I, which leads to increased neopterin production, in monocyte-derived macrophages. Sodium sulfite and sorbic acid suppressed both these biochemical changes in a dose-dependent way (P < 0.01 at 1 mM sodium sulfite and 50 mM sorbic acid). Data demonstrate a suppressive influence of sodium sulfite and sorbic acid on the activated Th1-type immune response. 相似文献
6.
Paul Wexberg MD BM Richard Pacher MD Suzanne Rdler MD Katharina Kiss MD Gilbert Beran MD Michael Grimm MD Gerald Maurer MD Dietmar Glogar MD FESC 《The Journal of heart and lung transplantation》2002,21(12):583-1263
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation. 相似文献
7.
Katharina Pachmann 《Clinical cancer research》2005,11(15):5657; author reply 5657-5657; author reply 5658
8.
W I Schievink B Mokri V V Michels D G Piepgras 《Stroke; a journal of cerebral circulation》1991,22(11):1426-1430
BACKGROUND AND PURPOSE: The familial occurrence of intracranial aneurysms and cervical artery dissections has been described in different families and supports the hypothesis that a primary arteriopathy may play a role in the pathogenesis of these disorders. Although the basis for this arteriopathy is generally not believed to be similar among cases of intracranial aneurysms and cervical artery dissections, several similarities exist in the epidemiology of these disorders and a common underlying arterial abnormality may be suspected. SUMMARY OF REPORTS: The medical records of all 175 patients with spontaneous dissections of the cervical arteries who were seen at the Mayo Clinic between 1970 and 1989 were reviewed to identify families in which intracranial aneurysms and cervical dissections coexisted. Three families were identified in which intracranial aneurysms and cervical artery dissections were observed among siblings. These families are described in detail. CONCLUSIONS: The familial occurrence of intracranial aneurysms and cervical artery dissections within the same families provides support to the importance of a common underlying arteriopathy in the pathogenesis of both these disorders. The underlying vascular defect may, at least in some cases, be inherited. 相似文献
9.
Clinicopathologic correlation of pigmented epiretinal membranes 总被引:1,自引:0,他引:1
G M Cherfan W E Smiddy R G Michels Z de la Cruz C P Wilkinson W R Green 《American journal of ophthalmology》1988,106(5):536-545
We performed clinicopathologic correlation on ten surgically removed pigmented epiretinal membranes causing macular pucker. All cases occurred in eyes with existing retinal holes or tears, including eight cases of macular pucker after previous retinal detachment. These cases probably represented a limited form of proliferative vitreoretinopathy. All membranes contained pigment epithelial cells with polarity, basement membrane, and melanosomes. Cytoplasmic melanin granules accounted for the clinical feature of pigmentation in these eyes. 相似文献
10.
Immunoglobulin Gene Rearrangement in Plasma Cell Dyscrasias: Detection of Small Clonal Cell Populations in Peripheral Blood and Bone Marrow 总被引:1,自引:0,他引:1
Falko Fend Katharina Weyrer Johannes Drach Andrea Schwaiger Florian Umlauft Kurt Grü newald 《Leukemia & lymphoma》1993,10(3):223-229
The bone marrow (BM) and peripheral blood (PB) samples of 71 patients with plasma cell dyscrasias were analysed by the Southern blot technique for the presence of clonal immunoglobulin (Ig) gene rearrangements. 53% of BM samples examined were archival material such as air dried BM slides or frozen trephine biopsies. The results were related to bone marrow plasmacytosis as determined by cytology and flow cytometry, and other clinical parameters. Clonal Ig gene rearrangements were found in BM samples of 45 (83%) of 54 MM patients and in 3 of 6 patients with monoclonal gammopathy of unknown significance (MGUS). Clonal cell populations in the PB were detected in 11 (30%) of 37 examined MM patients, but in none of the patients with MGUS or solitary plasmacytoma of bone. PB involvement was associated with progressive disease. Circulating monoclonal cells were significantly associated with higher M-protein levels (p 0.05). Thus, circulating clonal precursor cells are encountered more frequently in active MM. 相似文献