全文获取类型
收费全文 | 5495篇 |
免费 | 360篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 49篇 |
儿科学 | 90篇 |
妇产科学 | 75篇 |
基础医学 | 799篇 |
口腔科学 | 79篇 |
临床医学 | 532篇 |
内科学 | 1187篇 |
皮肤病学 | 88篇 |
神经病学 | 775篇 |
特种医学 | 469篇 |
外科学 | 672篇 |
综合类 | 60篇 |
一般理论 | 1篇 |
预防医学 | 276篇 |
眼科学 | 110篇 |
药学 | 321篇 |
中国医学 | 3篇 |
肿瘤学 | 288篇 |
出版年
2024年 | 7篇 |
2023年 | 61篇 |
2022年 | 85篇 |
2021年 | 163篇 |
2020年 | 91篇 |
2019年 | 121篇 |
2018年 | 133篇 |
2017年 | 127篇 |
2016年 | 149篇 |
2015年 | 156篇 |
2014年 | 202篇 |
2013年 | 260篇 |
2012年 | 414篇 |
2011年 | 429篇 |
2010年 | 250篇 |
2009年 | 203篇 |
2008年 | 368篇 |
2007年 | 369篇 |
2006年 | 348篇 |
2005年 | 309篇 |
2004年 | 304篇 |
2003年 | 242篇 |
2002年 | 240篇 |
2001年 | 80篇 |
2000年 | 61篇 |
1999年 | 73篇 |
1998年 | 66篇 |
1997年 | 61篇 |
1996年 | 31篇 |
1995年 | 25篇 |
1994年 | 28篇 |
1993年 | 21篇 |
1992年 | 32篇 |
1991年 | 40篇 |
1990年 | 30篇 |
1989年 | 32篇 |
1988年 | 28篇 |
1987年 | 26篇 |
1986年 | 24篇 |
1985年 | 30篇 |
1984年 | 21篇 |
1983年 | 19篇 |
1982年 | 16篇 |
1981年 | 5篇 |
1979年 | 18篇 |
1978年 | 12篇 |
1977年 | 7篇 |
1976年 | 11篇 |
1974年 | 5篇 |
1967年 | 4篇 |
排序方式: 共有5874条查询结果,搜索用时 15 毫秒
11.
12.
Horst J. Jaeger Klaus D. Mathias Udo Kempkes 《Cardiovascular and interventional radiology》1994,17(6):328-332
A 66-year-old man presented with bilateral subclavian steal syndrome (SSS) due to proximal subclavian artery occlusions. He was treated by percutaneous transluminal balloon angioplasty (PTA) and stent implantation in the left subclavian artery and by PTA alone in the right subclavian artery. We could demonstrate that interventional treatment of symptomatic bilateral SSS is possible. If PTA alone is insufficient, stent implantation should be considered. 相似文献
13.
Andrew C Hartwig Sarah I Mathias Alan S Law G F Gebhart 《Journal of oral and maxillofacial surgery》2003,61(11):1302-1309
PURPOSE: Experimental inflammation of the rat temporomandibular joint (TMJ) is commonly used to study trigeminal nociceptive processing. This study describes spontaneous pain-related behaviors following TMJ inflammation in the rat. The ability of preemptive systemic morphine to attenuate behaviors as well as immediate-early gene expression in the trigeminal nucleus is described. MATERIALS AND METHODS: Adult male Sprague-Dawley rats received an intra-articular injection of mustard oil (0% to 20%, 50 microL) and were observed for behavioral changes. Morphine sulfate (0 to 10 mg/kg SC) was given 30 minutes before mustard oil; this was reversed in one group with naltrexone hydrochloride (5 mg/kg SC). Two hours after injection rats were killed and perfused. Immunohistochemistry for the protein product of the immediate-early gene c-fos was performed, and brain stem sections including the trigeminal subnucleus caudalis were examined for positive nuclei. RESULTS: Mustard oil inflammation of the rat TMJ induces dose-dependent, morphine-sensitive behaviors. Behaviors observed included excessive grooming of the region, a chewing-like behavior, and head shaking. Fos expression in the trigeminal subnucleus caudalis parallels changes in behaviors. Morphine dose dependently attenuates the number of behaviors, as well as Fos expression; this effect is reversed by the micro-opioid receptor antagonist naltrexone. CONCLUSIONS: Mustard oil inflammation of the rat TMJ causes reliable behavioral changes, which may be quantified and, together with Fos expression, used to assess various experimental TMJ treatment modalities. 相似文献
14.
In multiple sclerosis (MS) up-regulation of β-adrenoceptors on peripheral blood mononuclear cells (PBMCs) has been attributed to either autonomic dysfunction, inflammation or a combination of the two. We have compared secondary progressive MS patients with normal subjects (NS) and two models of autonomic dysfunction; pure autonomic failure (PAF) and multiple system atrophy (MSA, Shy-Drager syndrome). There was up-regulation of β-adrenoceptors on PBMCs in MS and PAF patients but not in MSA patients. Only in PAF patients β-adrenoceptor up-regulation was correlated with low plasma levels of noradrenaline (NA) and adrenaline (Ad). In addition to studies in the basal state, measurements also were made after the centrally acting sympatholytic agent clonidine. These were combined with haemodynamic and neurohormonal measurements. After clonidine, there was a fall in blood pressure in NS and MSA patients but not in MS and PAF patients; a rise in growth hormone (GH) in NS and PAF patients but not in MS and MSA patients; and an up-regulation in PBMCs β-adrenoceptors in NS but not in MS, MSA and PAF patients. Up-regulation of β-adrenoceptors on PBMCs in MS could be attributed to autonomic dysfunction but the disparity between MS and PAF patients when considering their plasma levels of NA and Ad argue against. Although the neurohormonal responses to clonidine and the physiological assessment of autonomic function in progressive MS patients, demonstrate central autonomic dysfunction resembling that of the MSA patients, the normal basal β-adrenoceptor densities in the latter, suggests that the up-regulation of these receptors is independent of the central autonomic dysfunction in MS. 相似文献
15.
Sandrine Cappellesso Jean-Fran?ois Valentin Bruno Giraudeau Marie-Denise Boulanger Azmi Al-Najjar Mathias Büchler Jean-Michel Halimi Hubert Nivet Pierre Bardos Yvon Lebranchu Hervé Watier 《Nephrology, dialysis, transplantation》2004,19(2):439-443
BACKGROUND: Genetic factors other than HLA have been reported to be associated with the outcome of organ transplantations. Because binding of FasL to its receptor Fas could play an important role in tubulitis and in the death of graft tubular epithelial cells during kidney allograft rejection, a gene polymorphism recently identified in position -671 in the promoter of the TNFRSF6 gene coding for Fas was investigated in donors. METHODS: A case-control study was performed within a cohort of non-hyperimmunized adult patients who had received cadaveric kidney transplants based on the occurrence or absence of acute cellular rejection in the first 6 months after renal transplantation. Each recipient from the acute rejection group (n = 35) was matched for age (+/- 5 years) and number of HLA-DR mismatches with two recipients within the non-acute rejection group (n = 70). RESULTS: The TNFRSF6-GG genotype was more frequent in donors in the group without rejection episodes. In contrast, patients who received a kidney from a TNFRSF6-A carrier were more likely to experience acute rejection episodes (relative risk nearly 2.1). CONCLUSION: This study suggests that donor TNFRSF6 polymorphism directly or indirectly influences acute kidney rejection episodes. 相似文献
16.
Wilson's disease tremor is associated with magnetic resonance imaging lesions in basal ganglia structures. 总被引:1,自引:0,他引:1
Martin Südmeyer Andreas Saleh Lars Wojtecki Mathias Cohnen Joachim Gross Markus Ploner Harald Hefter Lars Timmermann Alfons Schnitzler 《Movement disorders》2006,21(12):2134-2139
Wilson's disease (WD) is an inherited disorder of copper metabolism yielding marked motor deficits, including a severely disabling tremor. As a structural correlate of the disease, a variety of cerebral abnormalities has been revealed. However, the relationship between motor deficits and cerebral lesions has remained largely unknown. Here, we investigated correlation between WD tremor and cerebral magnetic resonance imaging (MRI) findings. Cerebral MRI abnormalities in 6 symptomatic WD patients were compared to findings in 6 asymptomatic WD patients and 10 healthy controls. All patients were treated with long-term copper chelating therapy. Motor symptoms including tremor were determined by Unified Parkinson's Disease Rating Scale Part III (UPDRS-III). MRI findings in symptomatic WD patients revealed significant symmetric T2*-weighted hypointense signal alterations of globus pallidus, head of the caudate nucleus, and substantia nigra. In contrast, MRI of asymptomatic WD patients did not differ from healthy controls. Correlation analysis revealed a significant positive correlation between MRI basal ganglia lesions and UPDRS action tremor score. Our results demonstrate for the first time that Wilson's disease tremor is associated with lesions of the globus pallidus, the head of the caudate nucleus, and the substantia nigra. 相似文献
17.
18.
Jacques Borrelly Mathias Hossain Aazami 《European journal of cardio-thoracic surgery》2005,28(5):742-749
OBJECTIVE: The wisdom of surgery facing multiple and multi-focal ribs fractures (flail segment) remains controversial. By the present retrospective study, we sought to determine the advisability of surgery as well as the anatomical and biomechanical features of flail segment leading to secondary dislocation. METHOD: From 1970 to 2000, 127 patients underwent flail segment osteosynthesis. Clinical charts, operative reports and imaging data were reviewed retrospectively. Rib osteosynthesis was carried out with Judet staple and Kirschner wires until 1980, since then it has been undertaken with sliding-staples-struts. Postoperative chest X-ray was carried out to classify the flail segments into anterolateral and posterolateral types according to the location of anterior and posterior rib fractures. Each type was then divided into three subgroups of primary parietal, secondary parietal and retreat indications that were inferred retrospectively from final indications of rib osteosynthesis. RESULTS: The mean age of patients (ranging in age from 20 to 84 years) was 56+/-14.4 years with a male predominance (108/19). Seventy percent of flail segments was considered as posterolateral. The mean number of rib fractures per patient was 6+/-0.35. Rib osteosynthesis was undertaken with sliding-staples-struts in 70% of patients. The overall hospital mortality was 16%; it was subsequently reduced to 8% since sliding-staples-struts were used. The mean duration of ventilation was reduced from 5.8+/-0.76 days to 2.98+/-0.83 days with sliding-staples-struts. Seventy-seven percent of patients with posterolateral flail segment and primary parietal indication were extubated within the first 48 h postoperatively, whereas 46% of patients from other subgroups required ventilation for more than 5 days. Similarly, 83% of patients of the former subgroup returned to full previous level of activity compared with a rate of 52% for the latter subgroups. The flail segments were dislocated superoposteriorly for both anterolateral and posterolateral types, evoking the action of anterior serratus muscle. CONCLUSIONS: The anterolateral and posterolateral flail segments are rendered susceptible to secondary dislocation through a complex set of factors, of which the action of anterior serratus muscle is obvious. Restoration of parietal mechanics by early surgical reduction/fixation is a reliable therapeutic option in selected patients and offers encouraging results. 相似文献
19.
Robin M Heidemann Mark A Griswold Nicole Seiberlich Mathias Nittka Stephan A R Kannengiesser Berthold Kiefer Peter M Jakob 《Magnetic resonance in medicine》2007,57(6):1037-1046
MRI with non-Cartesian sampling schemes can offer inherent advantages. Radial acquisitions are known to be very robust, even in the case of vast undersampling. This is also true for 1D non-Cartesian MRI, in which the center of k-space is oversampled or at least sampled at the Nyquist rate. There are two main reasons for the more relaxed foldover artifact behavior: First, due to the oversampling of the center, high-energy foldover artifacts originating from the center of k-space are avoided. Second, due to the non-equidistant sampling of k-space, the corresponding field of view (FOV) is no longer well defined. As a result, foldover artifacts are blurred over a broad range and appear less severe. The more relaxed foldover artifact behavior and the densely sampled central k-space make trajectories of this type an ideal complement to autocalibrated parallel MRI (pMRI) techniques, such as generalized autocalibrating partially parallel acquisitions (GRAPPA). Although pMRI can benefit from non-Cartesian trajectories, this combination has not yet entered routine clinical use. One of the main reasons for this is the need for long reconstruction times due to the complex calculations necessary for non-Cartesian pMRI. In this work it is shown that one can significantly reduce the complexity of the calculations by exploiting a few specific properties of k-space-based pMRI. 相似文献
20.
The effect of desmopressin on nocturnal polyuria, overnight weight loss, and morning postural hypotension in patients with autonomic failure 总被引:4,自引:0,他引:4
C J Mathias P Fosbraey D F da Costa A Thornley R Bannister 《British medical journal (Clinical research ed.)》1986,293(6543):353-354
Day and night urine volume, morning and evening body weight, and supine and sitting blood pressure were measured in five patients with chronic autonomic failure who were not receiving treatment with drugs. All had nocturnal polyuria, overnight weight loss, and a pronounced postural fall in blood pressure, with lowest levels in the morning. Desmopressin (2-4 micrograms given intramuscularly at 8 pm) reduced nocturnal polyuria, diminished overnight weight loss, raised supine blood pressure, and reduced the postural fall, especially in the morning, when patients were often at their worst. Desmopressin may be a useful alternative to, or may supplement, other forms of treatment in some patients with autonomic failure. 相似文献