全文获取类型
收费全文 | 7220篇 |
免费 | 689篇 |
国内免费 | 25篇 |
专业分类
耳鼻咽喉 | 65篇 |
儿科学 | 165篇 |
妇产科学 | 189篇 |
基础医学 | 1002篇 |
口腔科学 | 112篇 |
临床医学 | 826篇 |
内科学 | 1655篇 |
皮肤病学 | 55篇 |
神经病学 | 620篇 |
特种医学 | 326篇 |
外科学 | 970篇 |
综合类 | 147篇 |
一般理论 | 9篇 |
预防医学 | 790篇 |
眼科学 | 124篇 |
药学 | 482篇 |
中国医学 | 10篇 |
肿瘤学 | 387篇 |
出版年
2023年 | 44篇 |
2022年 | 78篇 |
2021年 | 158篇 |
2020年 | 98篇 |
2019年 | 168篇 |
2018年 | 173篇 |
2017年 | 118篇 |
2016年 | 152篇 |
2015年 | 209篇 |
2014年 | 241篇 |
2013年 | 308篇 |
2012年 | 456篇 |
2011年 | 439篇 |
2010年 | 285篇 |
2009年 | 232篇 |
2008年 | 405篇 |
2007年 | 374篇 |
2006年 | 350篇 |
2005年 | 360篇 |
2004年 | 320篇 |
2003年 | 319篇 |
2002年 | 320篇 |
2001年 | 161篇 |
2000年 | 170篇 |
1999年 | 154篇 |
1998年 | 64篇 |
1997年 | 51篇 |
1996年 | 50篇 |
1995年 | 58篇 |
1994年 | 41篇 |
1993年 | 41篇 |
1992年 | 108篇 |
1991年 | 104篇 |
1990年 | 109篇 |
1989年 | 102篇 |
1988年 | 87篇 |
1987年 | 90篇 |
1986年 | 82篇 |
1985年 | 88篇 |
1984年 | 57篇 |
1983年 | 58篇 |
1982年 | 39篇 |
1980年 | 39篇 |
1979年 | 58篇 |
1978年 | 52篇 |
1977年 | 41篇 |
1974年 | 44篇 |
1973年 | 48篇 |
1972年 | 34篇 |
1971年 | 38篇 |
排序方式: 共有7934条查询结果,搜索用时 15 毫秒
41.
42.
Audit of 149 consecutive carotid endarterectomies performed by a single surgeon in a district general hospital over a 12-year period. 总被引:1,自引:1,他引:0 下载免费PDF全文
L. C. Tan G. L. Sutton N. J. Taffinder M. Perry T. Fail 《Annals of the Royal College of Surgeons of England》1996,78(4):340-344
Carotid endarterectomy has been established by two large randomised controlled trials (European Carotid Surgery Trial (ECST) and North American Symptomatic Carotid Endarterectomy Trial (NASCET)) as an important surgical procedure for the prevention of ischaemic strokes in patients presenting with transient cerebral ischaemia or non-disabling strokes attributable to severe ipsilateral carotid artery stenosis. The operation carries significant risk of death and stroke and it has been advocated by some that carotid endarterectomy should only be performed in a small number of designated regional centres in order to achieve good surgical results. It is doubtful that the regional centres alone can cope with the increasing numbers of patients requiring carotid endarterectomy and there is therefore a requirement for the procedure to be carried out by vascular surgeons in district general hospitals. It is important that surgical results are audited to ensure that comparable outcomes are achieved. We present an audit of our experience of carotid endarterectomy since 1981. A total of 149 consecutive carotid endarterectomies were performed by a single surgeon with a special interest in carotid surgery. The results are comparable to ECST with a 30-day mortality of 0% and an overall 30-day stroke rate of 5.7% (major strokes) for patients with severe, ie 70-99%, ipsilateral carotid artery stenoses. We have shown that carotid endarterectomy is an operation that can be performed safely and with good results by suitably trained surgeons in district general hospitals. 相似文献
43.
Summary In Malaysia, Tinospora crispa extract is taken orally by Type 2 (non-insulin-dependent) diabetic patients to treat hyperglycaemia. We have evaluated the claimed hypoglycaemic property by adding aqueous extract to the drinking water of normal and alloxan-diabetic rats. After one week, fasting blood glucose levels were significantly (p<0.01) lower and serum insulin levels were significantly (p<0.01) higher in treated diabetic animals (10.4±1.0 mmol/l and 12.8±1.1 U/ml respectively) compared to untreated diabetic controls (17.4±1.7 mmol/l and 8.0±0.7 U/ml respectively). The insulinotropic action of T. crispa was further investigated in vitro using isolated human or rat islets of Langerhans and HIT-T15 cells. In static incubations with rat islets and HIT-T15 B cells, the extract induced a dosage dependent stimulation and potentiation of basal and glucose-stimulated insulin secretion respectively. This insulinotropic effect was also evident in perifused human and rat islets and HIT-T5 B-cells. The observations that (i) in all three models insulin secretory rates rapidly returned to basal levels on removal of the extract and (ii) in rat islets, a second challenge with T. crispa induced an additional, stimulated response, are all consistent with physiological release of insulin by B cells. Moreover, the rate of HIT-T15 glucose utilisation was not affected by incubation with T. crispa, suggesting that the cells were viable throughout. These are the first studies to provide biochemical evidence which substantiates the traditional claims for an oral hypoglycaemic effect of Tinospora crispa, and which also show that the hypoglycaemic effect is associated with increased insulin secretion. 相似文献
44.
Summary The surfaces of 32 encrusted urinary catheters were examined by scanning electron microscopy to investigate the association of bacteria with the encrusting deposits. Deposits consisted of struvite crystals surrounded by aggregates of very small crystallites of hydroxyapatite. Underneath these minerals there was a layer of closely packed bacteria. Impressions of bacteria were also observed in hydroxyapatite. Crystals were often engulfed by the bacterial layer, which thus appeared to bind the crystals to each other and to the catheter surface. This thick layer of bacteria associated with crystals may protect both the bacteria from antibiotics and the crystals from acidic bladder washout solutions intended to dissolve them. Furthermore, the existence of this sessile population explains why urease-producing bacteria are not invariably detected in the urine of patients with encrusted catheters. The observation of this bacterial layer (or biofilm) by scanning electron microscopy provided direct evidence for infection being implicated in catheter encrustation. 相似文献
45.
Equine infectious anemia virus (EIAV) is a lentivirus that causes persistent infections in horses. We hypothesized that high-avidity CTL specific for nonvariable epitopes might be associated with low viral load and minimal disease in EIAV-infected horses. To test this hypothesis, memory CTL (CTLm) responses were analyzed in two infected horses with high plasma viral loads and recurrent disease (progressors), and in two infected horses with low-to-undetectable viral loads and mild disease (nonprogressors). High-avidity CTLm in one progressor recognized an envelope gp90 epitope, and the data documented for the first time in EIAV that viral variation led to CTL escape. Each of the nonprogressors had high-to-moderate avidity CTLm directed against epitopes within Rev, including the nuclear export and nuclear localization domains. These results suggested that the epitope specificity of high- and moderate-avidity CTLm was an important determinant for disease outcome in the EIAV-infected horses examined. 相似文献
46.
Invasive fungal sinusitis and meningitis due to Arthrographis kalrae in a patient with AIDS 总被引:2,自引:0,他引:2
Chin-Hong PV Sutton DA Roemer M Jacobson MA Aberg JA 《Journal of clinical microbiology》2001,39(2):804-807
We report the first described case of Arthrographis kalrae pansinusitis and meningitis in a patient with AIDS. The patient was initially diagnosed with Arthrographis kalrae pansinusitis by endoscopic biopsy and culture. The patient was treated with itraconazole for approximately 5 months and then died secondary to Pneumocytis carinii pneumonia. Postmortem examination revealed invasive fungal sinusitis that involved the sphenoid sinus and that extended through the cribiform plate into the inferior surfaces of the bilateral frontal lobes. There was also an associated fungal meningitis and vasculitis with fungal thrombosis and multiple recent infarcts that involved the frontal lobes, right caudate nucleus, and putamen. Post mortem cultures were positive for A. kalrae. 相似文献
47.
Dominant nonresponsiveness to Helicobacter pylori infection is associated with production of interleukin 10 but not gamma interferon 总被引:3,自引:0,他引:3 下载免费PDF全文
Helicobacter pylori-induced gastritis is an essential precursor lesion for the development of peptic ulcers or gastric adenocarcinoma. We demonstrate that nonresponsiveness to H. pylori SS1 infection is dominantly inherited in mice. F(1) hybrid crosses between a nonresponder mouse and three responder strains all possessed the nonresponder phenotype. Secretion of interleukin-10 but not gamma interferon was associated with nonresponsiveness to infection. 相似文献
48.
Identification of a novel mycobacterial histone H1 homologue (HupB) as an antigenic target of pANCA monoclonal antibody and serum immunoglobulin A from patients with Crohn's disease 下载免费PDF全文
Cohavy O Harth G Horwitz M Eggena M Landers C Sutton C Targan SR Braun J 《Infection and immunity》1999,67(12):6510-6517
pANCA is a marker antibody associated with inflammatory bowel disease (IBD), including most patients with ulcerative colitis and a subset with Crohn's disease. This study addressed the hypothesis that pANCA reacts with an antigen(s) of microbial agents potentially relevant to IBD pathogenesis. Using a pANCA monoclonal antibody, we have previously identified the C-terminal basic random-coil domain of histone H1 as a pANCA autoantigen. BLAST analysis of the peptide databases revealed H1 epitope homologues in open reading frames of the Mycobacterium tuberculosis genome. Western analysis of extracts from six mycobacterial species directly demonstrated reactivity to a single, conserved approximately 32-kDa protein. Direct protein sequencing, followed by gene cloning, revealed a novel 214-amino-acid protein, an iron-regulated protein recently termed HupB. Sequence analysis demonstrated its homology with the mammalian histone H1 gene family, and recombinant protein expression confirmed its reactivity with the 5-3 pANCA monoclonal antibody. Binding activity of patient serum immunoglobulin G (IgG) to HupB did not correlate with reactivity to histone H1 or pANCA, indicating the complex character of the pANCA antigen. However, anti-HupB IgA was strongly associated with Crohn's disease (P < 0.001). These findings indicate that the 5-3 pANCA monoclonal antibody detects a structural domain recurrent among mycobacteria and cross-reactive with a DNA-binding domain of histone H1. The association of HupB-binding serum IgA with IBD provides new evidence for the association of a mycobacterial species with Crohn's disease. 相似文献
49.
M. A. Gemmell S. N. Parmeter Rosemary J. Sutton Ngaire Khan 《Parasitology research》1981,64(2):135-147
The ability of three treatment schedules of mebendazole to kill well-established hydatid cysts was studied. Pregnant sheep, naturally infected withEchinococcus granulosus and/orTaenia hydatigena, were treated daily with mebendazole at a dose rate of 50 mg/kg body weight for either five days, one month, or three months.At autopsy, seven months after the commencement of treatment, no evidence was found that the 5-day treatment schedule had any damaging effect onE. granulosus cysts. The effects of the one month treatment were equivocal. There was evidence of a damaging effect from the 3-month treatment schedule and protoscoleces were not infective to dogs. NoT. hydatigena cysts survived the 1- and 3-month treatments, but organisms from the 5-day treatment were infective to dogs.These results forE. granulosus in sheep suggest that long-term treatment with mebendazole may be required in hydatid disease in man. The results obtained forT. hydatigena in sheep are discussed in relation to the treatment of cysticercosis fromT. solium in man. Mebendazole showed no untoward effect on the sheep or their lambs. 相似文献
50.
Role of Eotaxin-1 (CCL11) and CC chemokine receptor 3 (CCR3) in bleomycin-induced lung injury and fibrosis 下载免费PDF全文
Huaux F Gharaee-Kermani M Liu T Morel V McGarry B Ullenbruch M Kunkel SL Wang J Xing Z Phan SH 《The American journal of pathology》2005,167(6):1485-1496
Eotaxin-1/CCL11 and its receptor CCR3 are involved in recruitment of eosinophils to diverse tissues, but their role in eosinophil recruitment in pulmonary fibrosis is unclear. The present study examined the pulmonary expression of CCL11 and CCR3 during bleomycin (blm)-induced lung injury and determined their importance in the recruitment of inflammatory cells and the development of lung fibrosis. In mice, blm induced a marked pulmonary expression of CCL11 and CCR3. Immunostaining for CCR3 revealed that this receptor was not only expressed by eosinophils but also by neutrophils. CCL11-deficient (CCL11(-/-)) mice developed significantly reduced pulmonary fibrosis. Expression of profibrotic cytokines such as transforming growth factor-beta1 was diminished in the absence of CCL11. Furthermore, increased lung expression of CCL11 significantly enhanced blm-induced lung fibrosis and production of profibrotic cytokines. These effects were also associated with an increase of eosinophil and neutrophil pulmonary infiltration. In contrast, mice treated with neutralizing CCR3 antibodies developed significantly reduced pulmonary fibrosis, eosinophilia, neutrophilia, and expression of profibrotic cytokines. Together, these data suggest that CCL11 and CCR3 are important in the pulmonary recruitment of granulocytes and play significant pathogenic roles in blm-induced lung fibrosis. 相似文献