全文获取类型
收费全文 | 46409篇 |
免费 | 2748篇 |
国内免费 | 114篇 |
专业分类
耳鼻咽喉 | 678篇 |
儿科学 | 2102篇 |
妇产科学 | 1064篇 |
基础医学 | 5684篇 |
口腔科学 | 1939篇 |
临床医学 | 4413篇 |
内科学 | 9494篇 |
皮肤病学 | 1148篇 |
神经病学 | 3863篇 |
特种医学 | 1420篇 |
外国民族医学 | 2篇 |
外科学 | 7128篇 |
综合类 | 169篇 |
一般理论 | 17篇 |
预防医学 | 3067篇 |
眼科学 | 1321篇 |
药学 | 3021篇 |
中国医学 | 184篇 |
肿瘤学 | 2557篇 |
出版年
2023年 | 354篇 |
2022年 | 324篇 |
2021年 | 834篇 |
2020年 | 567篇 |
2019年 | 889篇 |
2018年 | 1386篇 |
2017年 | 993篇 |
2016年 | 1109篇 |
2015年 | 1125篇 |
2014年 | 1397篇 |
2013年 | 2109篇 |
2012年 | 3266篇 |
2011年 | 3682篇 |
2010年 | 1915篇 |
2009年 | 1399篇 |
2008年 | 3121篇 |
2007年 | 3359篇 |
2006年 | 3251篇 |
2005年 | 3285篇 |
2004年 | 3170篇 |
2003年 | 2907篇 |
2002年 | 2794篇 |
2001年 | 919篇 |
2000年 | 1000篇 |
1999年 | 662篇 |
1998年 | 391篇 |
1997年 | 322篇 |
1996年 | 258篇 |
1995年 | 230篇 |
1994年 | 196篇 |
1993年 | 179篇 |
1992年 | 156篇 |
1991年 | 129篇 |
1990年 | 124篇 |
1989年 | 115篇 |
1988年 | 102篇 |
1987年 | 93篇 |
1986年 | 101篇 |
1985年 | 68篇 |
1984年 | 82篇 |
1983年 | 73篇 |
1982年 | 69篇 |
1981年 | 54篇 |
1980年 | 63篇 |
1979年 | 74篇 |
1978年 | 56篇 |
1977年 | 55篇 |
1976年 | 44篇 |
1974年 | 46篇 |
1973年 | 48篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Isabelle Ville Jean-François Ravaud Catherine Diard Henri Paicheler 《Sociology of health & illness》1994,16(3):301-321
In this paper a social constructionist approach is used to frame an analysis of the effects of physical impairment on self-perception. The results are reported of a recent study in which questionnaires were mailed to 314 people who were paraplegic and 284 who were post-polio, as well as to a control group of 327 who had no visible physical impairments. While the people who were paraplegic and those who made up the control group gave similar answers to most of the survey questions, those who were post-polio displayed a consistent, but different, way of reporting on their self-representations. Moreover, this discourse, which included such self-described characteristics as self-control, a sense of duty, and a concern for meticulousness, was consistent in the post-polio group across sex and age. It is concluded that the date of onset of physical impairment is significant in influencing the self-representation of persons with physical impairments. The socio-historical evolution of social practices and cultural expectations and norms with respect to persons with disabilities in Western cultures were taken into account in interpreting the results of this survey. 相似文献
72.
Effects of granulocyte colony-stimulating factor on bacterial translocation due to burn wound sepsis
Orhan Yalçin Gürsel Soybir Ferda Köksoy Hakki Köse Recep Öztürk Baki Çokne§eli 《Surgery today》1997,27(2):154-158
The presence of certain defects in both cellular and humoral immunity after thermal injury has been established. Likewise,
the translocation of enteric bacteria to the mesenteric lymph nodes and to distant organs has also been observed following
serious thermal injury. The effects of granulocyte colony-stimulating factor (G-CSF) on bacterial translocation, the small
bowel mucosa, and cecal bacterial content were investigated in a rat model of burn wound sepsis in which albino Wistar rats
were scalded over 30% of their bodies, after which the lesions were infected by 1×108 colony-forming units (cfu)Pseudomonas aeruginosa. The control group was treated with 5% dextrose solution subcutaneously starting 2 days preburn, while the treatment group
received 100μg/kg human G-CSF subcutaneously. On the 4th day post burn all animals were killed to examine the bowel and culture
of the mesenteric lymph nodes (MLN), livers, and spleens. No significant differences were observed between the groups regarding
the cecal bacterial content and small bowel; however, a difference was seen in the ratio of translocation in the MLN liver
and spleen and quantitative MLN cultures. Based on these findings, G-CSF was thus found to be significantly effective in reducing
bacterial translocation due to burn wound sepsis. 相似文献
73.
Comparison of the inflammatory response between miniaturized and standard CPB circuits in aortic valve surgery. 总被引:1,自引:0,他引:1
Olivier M Bical Yves Fromes Didier Gaillard Marc Fischer Olivier Ponzio Philippe Deleuze Marie-Fran?oise Gerhardt Fran?ois Trivin 《European journal of cardio-thoracic surgery》2006,29(5):699-702
OBJECTIVE: One of the complications of CPB is the systemic inflammatory response syndrome (SIRS). Recent developments tend to minimize the biological impact of CPB in using miniaturized closed circuit with reduced priming volume and less blood-air interface. The benefit of these miniaturized closed circuits in terms of inflammatory response has been proved in coronary surgery. However, in open heart surgery, the CPB circuit is no more closed and the benefit of the miniaturized set-up could disappear. The aim of the study is to compare the SIRS between standard and miniaturized circuits in aortic surgery. METHODS: Forty patients who underwent singular aortic valve replacement were randomly assigned either to a standard CPB (group A, n=20) or to a miniaturized CPB (group B, n=20). Pertinent clinical and surgical data were collected. Hematological parameters (leukocyte and neutrophil counts) and biochemical parameters (C-reactive protein, cytokine tests) were determined pre-, on and post-CPB. RESULTS: There were an increase in leukocyte and neutrophil counts and a decline in hematocrit in both groups. In both groups, there was a raise after CPB, in C-reactive protein, IL-6, TNF-alpha, neutrophil elastase, and IL-10. However, the raises of elastase and TNF-alpha were significantly lower after the weaning of miniaturized CPB (116+/-46 ng/ml and 10+/-4 pg/ml, respectively) compared to standard CPB (265+/-120 ng/ml, P=0.01 and 18+/-7 pg/ml, P=0.03). The raise of IL-10 is also lower with miniaturized circuit (15+/-6 pg/ml) compared to standard circuit (51+/-26, P=0.004). CONCLUSIONS: This study demonstrates in aortic surgery, the lesser inflammatory response of a miniaturized CPB compared to a standard CPB. However, there is always some inflammation after CPB and a small bio-reactive free perfusion circuit is still to be found in open heart surgery. 相似文献
74.
75.
A strain of Aspergillus fumigatus has been isolated from sediments of a mussel bed. When cultured in hyper saline conditions (with sea-water), it produces a cytotoxic and immunosuppressive toxin, gliotoxin, which is excreted in an exudate. In order to know if this toxin could represent a risk for shellfish consumers, an experiment of bioaccumulation of gliotoxin in mussel has been carried out. After 6 days of contamination, toxin was accumulated in the meat of the mussels, at a level up to 2.9 microg/mg of extract weight, with a mode of contamination different to the classical digestive process described for a majority of marine toxins, but similar to the contamination mode of domoic acid. 相似文献
76.
Marc Hermier Norbert Nighoghossian Laurent Derex Patrice Adeleine Marlène Wiart Yves Berthezène Fran?ois Cotton Jean-Baptiste Pialat Pascal Dardel Jér?me Honnorat Paul Trouillas Jean-Claude Froment 《Journal of cerebral blood flow and metabolism》2003,23(11):1362-1370
Prediction of hemorrhagic transformation (HT) in patients treated by intravenous recombinant tissue-type plasminogen activator (rt-PA) is a challenging issue in acute stroke management. HT may be correlated with severe hypoperfusion. Signal changes may be observed at susceptibility-weighted magnetic resonance imaging (MRI) within large perfusion defects. A signal drop within cerebral veins at T2*-weighted gradient-echo MRI may be expected in severe ischemia, and may indicate subsequent risk of HT. The authors prospectively searched for an abnormal visibility of transcerebral veins (AVV) within the ischemic area in patients with hemispheric ischemic stroke, before they were treated with intravenous rt-PA therapy. Any correlation between AVV and baseline clinical or MRI findings, or further HT, was noted. An AVV was present in 23 of 49 patients (obvious, n = 8; moderate, n = 15), and was supported by severe hemodynamic changes at baseline MRI. The AVV was correlated with the occurrence of parenchymal hematoma type 2 at computed tomography during the first week (r = 0.44, P = 0.002). Five of six type 2 parenchymal hematomas occurred in association with obvious AVV. At multiple regression analysis, two baseline MRI factors had an independent predictive value for HT risk during the first week: the AVV and the cerebral blood volume ratio (Nagelkerke R2 = 0.48). 相似文献
77.
Cevat Uçar 《European archives of oto-rhino-laryngology》2006,263(12):1082-1086
We used inferior pedicled composite multi-fractured osteoperiosteal flap (CMOF), our original and new surgical approach, to obliterate the mastoid cavity and reconstruct the external auditory canal (EAC) to prevent the open cavity problems. CMOF was used to obliterate the mastoid cavity and reconstruct the EAC in 24 patients (13 women, 11 men; age span 12–51 years) who underwent radical mastoidectomy to treat the chronic otitis media between 1998 and 2004. Small meatoplasty was done in all 24 patients to relive their aesthetical concerns. Temporal bone CT scanning was done to observe the neo-osteogenesis in the mastoidectomy cavity and the CMOF, and the EAC volume was measured postoperatively. All our patients were followed-up for 2 years. The epithelization of the new EAC in our patients was complete at the end of the second month. Cholesteatoma, granulation, and recurrence of osteitis did not occur in any of the patients. We saw the new bone formation filling the mastoid cavity in the postoperative temporal bone CT scanning images. The mean volume of the new EAC on the 24th month was 1.83 ± 0.56 cm3. We had an almost natural EAC, which owed its existence to the neo-osteogenesis that grows behind the CMOF, which we use to obliterate the mastoid cavity and to reconstruct the EAC.This technique, composite multi-fractured osteoperiosteal flap, was presented in the symposium of Gulhane Military Medical Academy on otology and audiology, 15–18 September, 2005, Antalya, Turkey. 相似文献
78.
Mitochondrial function and mitochondrial DNA in a series of 64 patients suspected of having mitochondrial myopathy 总被引:1,自引:0,他引:1
C Marsac F Degoul G Bonne N Romero I Nelson M Fardeau D Fran?ois G Ponsot J P Harpey B Eymard 《Revue neurologique》1991,147(6-7):462-466
Biochemical results concerning 64 patients suspected of mitochondrial myopathies are presented. Four clinical groups were studied including 21 encephalomyopathies, 42 ocular myopathies, 8 isolated myopathies and 3 cardiomyopathies. In 26 cases, the coexistence of a normal mitochondrial DNA and a mutated mitochondrial DNA (heteroplasmy) was found (19 simple deletions, 4 multiple deletions and 3 punctual mutations) and all cases presented with ocular disorders (excepted 2 cases with MERRF). Furthermore, 1 complex I deficiency (1 ocular myopathy), 1 complex IV deficiency (1 adult encephalomyopathy type Leigh), 3 complexes I + IV deficiencies (2 cases with a cardiomyopathy and 1 familial MELAS) and 2 pyruvate (1 adult from of Leigh's encephalomyopathy) dehydrogenase deficiencies (clinically and genetically different) did not show evidence of mitochondrial DNA mutation. 相似文献
79.
Acute subdural hematoma: Outcome and outcome prediction 总被引:3,自引:0,他引:3
R. Kemal Koç M.D. Hidayet Akdemir I. Suat Öktem Mehmet Meral Ahmet Menkü 《Neurosurgical review》1997,20(4):239-244
Patients with traumatic acute subdural hematoma were studied to determine the factors influencing outcome.Between January 1986 and August 1995, we collected 113 patients who underwent craniotomy for traumatic acute subdural hematoma. The relationship between initial clinical signs and the outcome 3 months after admission was studied retrospectively.Functional recovery was achieved in 38% of patients and the mortality was 60%. 91% of patients with a high Glasgow Coma Scale (GCS) score (9–15) and 23% of patients with a low GCS score (3–8) achieved functional recovery. All of 14 patients with a GCS score of 3 died. The mortality of patients with GCS scores of 4 and 5 was 95% to 75%, respectively. Patients over 61 years old had a mortality of 73% compared to 64% mortality for those aged 21–40 years. 97% of patients with bilateral unreactive pupil and 81% of patients with unilateral unreactive pupil died. The mortality rates of associated intracranial lesions were 91% in intracerebral hematoma, 87% in subarachnoid hemorrhage, 75% in contusion.Time from injury to surgical evacuation and type of surgical intervention did not affect mortality. Age and associated intracranial lesions were related to outcome. Severity of injury and pupillary response were the most important factors for predicting outcome. 相似文献
80.
The relaxant effects of electrical field stimulation (EFS) and exogenously applied acetylcholine (ACh) or acidified NaNO2 (a-NaNO2) were investigated in the isolated mouse corpus cavernosum precontracted with phenylephrine hydrochloride (PE). Tetrodotoxin (TTX) blocked the relaxant effects of EFS completely, whereas it had no effect on the responses to ACh or a-NaNO2. Guanethidine and indomethacin failed to affect the electrically or ACh-induced relaxations. Atropine completely blocked the effect of ACh; however, it caused a slight reduction in the relaxation evoked by EFS.N
G- Nitro-l-arginine (l-NOARG) reduced the effects of EFS and ACh significantly, but it was ineffective on the relaxations induced by a-NaNO2. The inhibitory action ofl-NOARG was partly restored byl-arginine, but not byd-arginine. Methylene blue (MB) and hydroxocobalamin (HC) exhibited significant inhibition on the relaxations evoked by EFS, ACh and a-NaNO2. Hydroquinone (HQ) reduced relaxation due to a-NaNO2, but did not affect that of EFS and ACh. Our findings suggest that EFS-induced relaxations of mouse cavernosal tissue are mediated by a transmitter which probably resembles an organic nitrate. 相似文献