全文获取类型
收费全文 | 3186244篇 |
免费 | 252992篇 |
国内免费 | 5456篇 |
专业分类
耳鼻咽喉 | 45424篇 |
儿科学 | 100176篇 |
妇产科学 | 86297篇 |
基础医学 | 457721篇 |
口腔科学 | 91813篇 |
临床医学 | 295359篇 |
内科学 | 617077篇 |
皮肤病学 | 66006篇 |
神经病学 | 265280篇 |
特种医学 | 124714篇 |
外国民族医学 | 1104篇 |
外科学 | 471404篇 |
综合类 | 73760篇 |
现状与发展 | 4篇 |
一般理论 | 1436篇 |
预防医学 | 262240篇 |
眼科学 | 75213篇 |
药学 | 237583篇 |
10篇 | |
中国医学 | 5740篇 |
肿瘤学 | 166331篇 |
出版年
2018年 | 32875篇 |
2016年 | 27909篇 |
2015年 | 31728篇 |
2014年 | 45214篇 |
2013年 | 69068篇 |
2012年 | 93232篇 |
2011年 | 98890篇 |
2010年 | 57994篇 |
2009年 | 55604篇 |
2008年 | 93845篇 |
2007年 | 100129篇 |
2006年 | 100461篇 |
2005年 | 98085篇 |
2004年 | 94329篇 |
2003年 | 90956篇 |
2002年 | 89470篇 |
2001年 | 142945篇 |
2000年 | 147492篇 |
1999年 | 124920篇 |
1998年 | 36519篇 |
1997年 | 33094篇 |
1996年 | 33136篇 |
1995年 | 31707篇 |
1994年 | 29821篇 |
1993年 | 27889篇 |
1992年 | 100953篇 |
1991年 | 98152篇 |
1990年 | 94911篇 |
1989年 | 91566篇 |
1988年 | 85168篇 |
1987年 | 83702篇 |
1986年 | 79584篇 |
1985年 | 75881篇 |
1984年 | 57665篇 |
1983年 | 49801篇 |
1982年 | 30145篇 |
1981年 | 26988篇 |
1980年 | 25367篇 |
1979年 | 54626篇 |
1978年 | 38971篇 |
1977年 | 32801篇 |
1976年 | 30695篇 |
1975年 | 32653篇 |
1974年 | 40086篇 |
1973年 | 38530篇 |
1972年 | 36343篇 |
1971年 | 33710篇 |
1970年 | 31714篇 |
1969年 | 29665篇 |
1968年 | 27224篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Predictors of clustering of tuberculosis in Greater Vancouver: a molecular epidemiologic study 总被引:3,自引:0,他引:3 下载免费PDF全文
993.
In einer clusteranalytischen Untersuchung mit 137 Patienten, die einen Parasuizid verübt hatten, wurden 6 Subgruppen unter Berücksichtigung der Klassifikationsvariable “suicide intent” isoliert. Es wurde die Hypothese geprüft, dass sich sowohl die Motivstrukturen als auch die Raten an wiederholten Parasuiziden in Abh?ngigkeit der Clusterl?sung bedeutsam voneinander unterscheiden. Die Ergebnisse unterstützen die Annahme einer zunehmenden Ausdifferenzierung der interpersonell orientierten Motivstrukturen mit sinkendem bzw. einer Einengung der Motivstruktur auf den Todeswunsch mit steigendem “suicide intent”. Es wurden folgende Subgruppen differenziert: eine Suizid-Hochrisikogruppe mit ausschlie?licher Todesintention und -motivation, 2 moderate Suizid-Risikogruppen mit hoher Todesintention und leichten Tendenzen zu interpersoneller Motivation, eine Subgruppe, gekennzeichnet durch eine manipulativ/strategisch orientierte Motivstruktur und auff?llig h?ufigen Parasuizidwiederholungen, eine Subgruppe mit vorrangig appellativ orientierten Motiven, Kontrollverlust und vergleichsweise seltenen Parasuizidwiederholungen und eine Subgruppe mit ambivalenter Motivstruktur (interpersonell und todesorientiert). 相似文献
994.
The authors studied the cumulative probability of pregnancy for up to 4 consecutive embryo transfer (ET) cycles with ICSI performed for male factor. Transfers could be either fresh or frozen. The clinical pregnancy rate (PR) for the first 4 cycles were similar [44% (61/366); 31% (44/138); 45% (14/31); 44% (4/9)]. Delivery rates were also similar. There was a lower PR on the second retrieval vs. the first retrieval (47% vs. 29%), but this may be related to most of the second retrievals occurring in the second transfer cycle (67%, 31/55); this may be explained by women who were poor responders and required another retrieval without a frozen ET. The majority of transfers in cycle 1 were fresh, whereas cycles 2-4 used primarily frozen-thawed embryos. These data should be helpful for patients requiring IVF with ICSI in deciding to continue with more IVF cycles or consider other 相似文献
995.
I Luyeye C Fievet J C Dupont C Durieux N Slimane J F Lecocq C Demarquilly J C Fruchart 《Clinical biochemistry》1988,21(4):255-261
Predefined monoclonal antibodies (Mabs) were used in an immunoenzymometric assay to study the immunochemical heterogeneity of lipoproteins and to search for potential epitopes with pathological importance. By measuring apolipoprotein B (apo B) epitopes in patients with and without angiographically documented coronary artery disease and in patients with type IIa hyperlipoproteinemia, we have found that both types of patients have a significant increase in Apo B-containing particles specifically recognized by one Mab (BL3). We have also observed that the effects of fenofibrate on type IIa patients vary greatly depending on the plasma concentrations of various Apo B-containing lipoproteins. The greatest effects occurred in patients with epitopes recognized by BL3. Lastly, by sequential precipitation of specific epitopes by BL3, we have obtained evidence that the residual epitope(s) may be related to one or more lipoprotein particles. 相似文献
996.
997.
J D Woolgar D S Reddy J V Robbs 《European journal of vascular and endovascular surgery》2002,23(3):255-259
OBJECTIVES: to examine the management and outcome of patients with traumatic popliteal artery pseudoaneurysms with delayed presentation. MATERIALS: over a 2-year period 7 patients with traumatic popliteal pseudoaneurysms presenting to a tertiary referral unit after a delay of 1 month were reviewed. METHODS: a retrospective review of clinical records. RESULTS: the median interval between injury and presentation was 1.5 months (range 1-24 months). Penetrating trauma from gunshot wounds was the cause of the initial vascular injury in 6 patients and a stab wound in one. All patients had large pseudoaneurysms of more than 8 cm filling the popliteal fossa with variable degrees of fixed flexion deformity (FFD) of the knee. Severe FFD of more than 40 degrees was noted in 2 patients and 3 others had mild flexion deformities of 10 to 20 degrees. Six patients underwent repair of the pseudoaneurysm. One patient required an above knee amputation due to an infected false aneurysm. There were no deaths or graft related complications. Despite aggressive post-operative physiotherapy only 2 patients were able to completely straighten the leg at the time of discharge. CONCLUSIONS: in patients with neglected popliteal artery pseudoaneurysms, morbidity is associated with the pre-operative degree of fixed flexion deformity of the knee. 相似文献
998.
999.
1000.
J?rg Müller Klaus Seppi Nadia Stefanova Werner Poewe Irene Litvan Gregor K Wenning 《Movement disorders》2002,17(5):1041-1045
The frequency and pathophysiology of freezing of gait (FoG) in atypical parkinsonism is unknown. We analysed the frequency of FoG in postmortem-confirmed atypical parkinsonian disorders (APD) comprising corticobasal degeneration (CBD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). Sixty-six patients with pathologically confirmed APD (CBD, n = 13; DLB, n = 14; MSA, n = 15; PSP, n = 24) formed the basis for a multicenter clinicopathological study. Clinical features at first and last clinical visit were abstracted from patient records on standardized forms following strict instructions. At the first visit (median 36 months after symptom onset), 24% of APD had FoG (CBD, 8%; DLB, 21%; PSP, 25%; MSA, 40%). Logistic regression analysis showed a significant association of FoG and urinary incontinence (P = 0.04) at first visit. At last visit, 47% of APD had FoG (CBD, 25%; PSP, 53%; DLB, 54%; MSA, 54%). Clinicopathological correlation based on routine postmortem examination failed to identify a consistent neuropathological substrate of FoG. This study demonstrates that (1) FoG is common in APD, and (2) urinary incontinence is significantly associated with FoG in these disorders. Whether FoG and urinary incontinence share similar neuropathological substrates remains to be determined by future studies. 相似文献