全文获取类型
收费全文 | 45699篇 |
免费 | 5056篇 |
国内免费 | 152篇 |
专业分类
耳鼻咽喉 | 325篇 |
儿科学 | 1349篇 |
妇产科学 | 907篇 |
基础医学 | 6290篇 |
口腔科学 | 1235篇 |
临床医学 | 5835篇 |
内科学 | 9025篇 |
皮肤病学 | 769篇 |
神经病学 | 3636篇 |
特种医学 | 1884篇 |
外国民族医学 | 1篇 |
外科学 | 6028篇 |
综合类 | 1215篇 |
一般理论 | 26篇 |
预防医学 | 5281篇 |
眼科学 | 852篇 |
药学 | 3815篇 |
中国医学 | 80篇 |
肿瘤学 | 2354篇 |
出版年
2021年 | 588篇 |
2020年 | 361篇 |
2019年 | 647篇 |
2018年 | 736篇 |
2017年 | 532篇 |
2016年 | 604篇 |
2015年 | 713篇 |
2014年 | 959篇 |
2013年 | 1388篇 |
2012年 | 1993篇 |
2011年 | 2001篇 |
2010年 | 1147篇 |
2009年 | 1109篇 |
2008年 | 1907篇 |
2007年 | 2052篇 |
2006年 | 1973篇 |
2005年 | 1898篇 |
2004年 | 1745篇 |
2003年 | 1666篇 |
2002年 | 1628篇 |
2001年 | 1556篇 |
2000年 | 1482篇 |
1999年 | 1477篇 |
1998年 | 613篇 |
1997年 | 507篇 |
1996年 | 499篇 |
1995年 | 516篇 |
1994年 | 454篇 |
1993年 | 493篇 |
1992年 | 1223篇 |
1991年 | 1133篇 |
1990年 | 1094篇 |
1989年 | 1070篇 |
1988年 | 988篇 |
1987年 | 979篇 |
1986年 | 990篇 |
1985年 | 907篇 |
1984年 | 779篇 |
1983年 | 645篇 |
1982年 | 435篇 |
1981年 | 361篇 |
1979年 | 593篇 |
1978年 | 490篇 |
1977年 | 380篇 |
1976年 | 393篇 |
1974年 | 437篇 |
1973年 | 407篇 |
1972年 | 393篇 |
1971年 | 355篇 |
1969年 | 362篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
R C Ayres S G Hübscher J Shaw C Garner R Joplin A Williams J M Neuberger 《The Journal of pathology》1991,165(2):153-161
We have produced a range of monoclonal antibodies which stain human intrahepatic bile ducts of different sizes. Amongst 26 monoclonal antibodies produced, five clones reacted specifically with bile ducts of different sizes, of which three have been maintained in culture and their viability following freezing and thawing confirmed. Staining patterns varied between normal adult liver tissue, normal fetal liver tissue and a variety of hepatobiliary diseases. The antibodies provide further evidence of the immunological heterogeneity of the human intrahepatic biliary tree and support the hypothesis that proliferating bile ductules are derived from periseptal hepatocytes. The preparation of the antibodies, their staining reactions in normal adult, normal fetal and a variety of liver diseases are described. 相似文献
32.
D R Sandeman A P Sandeman P Buxton H H Hughes D W Chadwick I R Williams R D Baker P M Foy D M Shaw 《British journal of neurosurgery》1990,4(4):299-312
The management of patients presenting with supratentorial glioma between 1978 and 1986 is reviewed. Complete follow-up in 517 cases was obtained. One hundred and fifty eight patients were not submitted to any form of surgery, 299 patients were biopsied and 60 patients underwent craniotomy and internal decompression. The no surgery group contained a higher proportion of patients with poor prognostic indicators than either the biopsy or craniotomy groups. The craniotomy group consisted of patients with better prognostic indicators than the biopsy group, in particular, younger age and more favourable site, type and grade of tumour. This was reflected in the difference in outcome between the groups. Median survival was 14 months in the craniotomy group, four months in the biopsy group and 2.2 months in the no surgery group. The outcome in patients with histologically proven malignant gliomas was best in those patients who received radiotherapy. The craniotomy group had a median survival of 18.5 months, a two year survival of 48% and a five year survival of 9%. The median survival following radiotherapy of those patients with proven malignant gliomas who had a biopsy was 9.5 months with a two year survival of 16% and a five year survival of 2%. These results compare favourably with studies which have adopted a more aggressive approach, suggesting that outcome is determined as much by patient selection using favourable prognostic indicators as by the treatment itself. The need for prospective trials of the management of unselected consecutive glioma patients randomizing them to conservative and radical treatment groups in order to define the role of both conventional therapy and radical therapy is discussed. 相似文献
33.
Interaction between insulin and glucose-delivery route in regulation of net hepatic glucose uptake in conscious dogs 总被引:5,自引:0,他引:5
B A Adkins-Marshall S R Myers G K Hendrick P E Williams K Triebwasser B Floyd A D Cherrington 《Diabetes》1990,39(1):87-95
In the presence of fixed basal levels of insulin, the route of intravenous glucose delivery (protal vs. peripheral) determines whether net hepatic glucose uptake (NHGU) occurs. Our aims were to determine if the route of intravenous glucose delivery also plays a role in regulating NHGU in the presence of hyperinsulinemia and to determine if length of fast (18 vs. 36 h) influences regulation of NHGU. Five conscious dogs fasted 18 h were given somatostatin and replacement insulin (245 +/- 34 microU.kg-1.min-1) and glucagon (0.65 ng.kg-1.min-1) infusions intraportally. After a 40-min control period, the insulin infusion rate was increased fourfold, and glucose was infused for 3 h. Glucose was given either through a peripheral vein or the portal vein for 90 min to double the glucose load reaching the liver. The order of infusions was randomized. NHGU was measured with the arterial - venous difference technique. Insulin and glucagon levels were 12 +/- 2, 35 +/- 6, and 36 +/- 5 microU/ml and 55 +/- 12, 61 +/- 13, and 59 +/- 7 pg/ml during the control, peripheral, and portal infusions, respectively. The glucose infusion rate, the load of glucose reaching the liver, and the arterial-portal plasma glucose gradient were 0, 9.58 +/- 2.28, and 10.44 +/- 2.94 mg.kg-1.min-1; 29.4 +/- 3.6, 56.8 +/- 3.4, and 56.8 +/- 2.8 mg.kg-1.min-1; and 2 +/- 1, 5 +/- 1, and -51 +/- 15 mg/dl during the same periods.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
34.
Paul R. Finley R. Jane Williams Carla Fletcher 《Journal of clinical laboratory analysis》1988,2(4):249-255
We have devised assays to detect both circulating alloantibodies to platelets (indirect assay) and platelet-association IgG and IgM (direct assay) using a flow cytometric technique. A variety of patients with immune thrombocytopenia were studied. Employment of a confocal lens in the flow cytometer increased the discrimination power of the instrument. Patients with autoimmune thrombocytopenia (idiopathic thrombocytic purpura [ITP], systemic lupus erythematosus (SLE), lymphoma, leukemia, and drug-induced thrombocytopenia showed a significant increase in platelet-associated antibody. Circulating antibodies to platelets (alloantibodies) were demonstrated in cases of platelet refractoriness and neonatal isoimmune purpura. Day-today precision of the assays ranged from 3% to 6% (coefficient of variation). No interference was shown in the presence of hemoglobin (5 g/L), triglycerides (10 g/L), or polyclonal and monoclonal immunoglobulinemia (50 g/L: IgG, IgA, IgM). The sensitivity of the direct assay was 500 attograms of IgG or IgM platelet. 相似文献
35.
M. P. Williams M. R. Hamilton J. C. Sercombe & R. E. Pounder 《Alimentary pharmacology & therapeutics》1997,11(4):705-710
Background: Dual therapy with ranitidine bismuth citrate plus clarithromycin twice daily for 14 days is an effective regimen for eradicating Helicobacter pylori infection.
Aim: To determine whether this regimen can be improved by the addition of a second antibiotic, tetracycline hydrochloride, whilst reducing the duration of treatment to 7 days.
Methods: Sixty-one out-patients were enrolled to this open treatment study. All had H. pylori infection, as determined by13 C-urea breath test and, for those undergoing endoscopy, by rapid urease test. Patients were treated with ranitidine bismuth citrate 400 mg, clarithromycin 500 mg and tetracycline hydrochloride 500 mg all twice daily for 7 days. Eradication of H.␣pylori was assessed by two separate 13 C-urea breath tests, the first 28–68 days after the completion of treatment, the second 28–162 days later. H. pylori infection was considered cured if both tests were negative.
Results: All 61 patients were included in the intention-to-treat efficacy analysis. Successful eradication of H.␣pylori was achieved in 55/61 patients (90 %; 95% CI: 82–98%). Fifty-nine out of sixty-one patients reported 100% compliance; one patient missed a single dose of medication and the other withdrew at 48 h due to nausea and vomiting. Minor adverse events were reported by 30/61 patients.
Conclusion: One-week triple therapy with ranitidine bismuth citrate, clarithromycin and tetracycline, all twice daily, is a safe and well-tolerated regimen which eradicates H. pylori in 90% of infected patients. 相似文献
Aim: To determine whether this regimen can be improved by the addition of a second antibiotic, tetracycline hydrochloride, whilst reducing the duration of treatment to 7 days.
Methods: Sixty-one out-patients were enrolled to this open treatment study. All had H. pylori infection, as determined by
Results: All 61 patients were included in the intention-to-treat efficacy analysis. Successful eradication of H.␣pylori was achieved in 55/61 patients (90 %; 95% CI: 82–98%). Fifty-nine out of sixty-one patients reported 100% compliance; one patient missed a single dose of medication and the other withdrew at 48 h due to nausea and vomiting. Minor adverse events were reported by 30/61 patients.
Conclusion: One-week triple therapy with ranitidine bismuth citrate, clarithromycin and tetracycline, all twice daily, is a safe and well-tolerated regimen which eradicates H. pylori in 90% of infected patients. 相似文献
36.
Martin Williams 《Transfusion and apheresis science》2007,36(2):213-214
37.
38.
39.
Johannes Bjornsson John R. Goellner David Eugene Williams Mary V. Scheiber 《Journal of cancer research and clinical oncology》1986,111(3):289-290
Preoperative cytologic examinations were performed on bronchial material from 92 patients with postsurgical (pathologic) stage I (American Joint Committee) adenocarcinoma of the lung. All patients were followed up for at least 5 years or until death; thus, cases of adenocarcinoma metastatic to the lungs were virtually excluded. Only 22 patients (24%) had abnormal preoperative cytologic findings. This low cytologic sensitivity is ascribed to the small size and peripheral location of the tumors. Large lesions of high histologic grades were more likely to have positive preoperative cytologic findings than small, well-differentiated ones. 相似文献
40.
Guido Currarino M.D. Bernita Williams M.D. Joan S. Reisch Ph.D. 《Skeletal radiology》1986,15(8):628-630
The length of the thoracic spine was measured in chest roentgenograms of 331 children from birth to 16 years and standards for thoracic spine length in this age group were obtained. 相似文献