全文获取类型
收费全文 | 1806篇 |
免费 | 39篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 30篇 |
妇产科学 | 40篇 |
基础医学 | 73篇 |
口腔科学 | 54篇 |
临床医学 | 382篇 |
内科学 | 530篇 |
皮肤病学 | 80篇 |
神经病学 | 47篇 |
外国民族医学 | 2篇 |
外科学 | 172篇 |
综合类 | 1篇 |
一般理论 | 16篇 |
预防医学 | 129篇 |
眼科学 | 20篇 |
药学 | 221篇 |
肿瘤学 | 31篇 |
出版年
2017年 | 11篇 |
2016年 | 14篇 |
2015年 | 21篇 |
2014年 | 22篇 |
2013年 | 30篇 |
2012年 | 10篇 |
2010年 | 50篇 |
2009年 | 45篇 |
2008年 | 13篇 |
2007年 | 15篇 |
2006年 | 13篇 |
2003年 | 15篇 |
2001年 | 12篇 |
2000年 | 15篇 |
1999年 | 45篇 |
1998年 | 68篇 |
1997年 | 102篇 |
1996年 | 102篇 |
1995年 | 70篇 |
1994年 | 80篇 |
1993年 | 78篇 |
1992年 | 69篇 |
1991年 | 72篇 |
1990年 | 66篇 |
1989年 | 49篇 |
1988年 | 57篇 |
1987年 | 47篇 |
1986年 | 66篇 |
1985年 | 40篇 |
1984年 | 40篇 |
1983年 | 32篇 |
1982年 | 38篇 |
1981年 | 28篇 |
1980年 | 33篇 |
1979年 | 20篇 |
1978年 | 28篇 |
1977年 | 23篇 |
1976年 | 25篇 |
1975年 | 21篇 |
1974年 | 11篇 |
1972年 | 11篇 |
1971年 | 20篇 |
1970年 | 14篇 |
1969年 | 10篇 |
1968年 | 16篇 |
1966年 | 15篇 |
1965年 | 17篇 |
1964年 | 11篇 |
1955年 | 15篇 |
1954年 | 14篇 |
排序方式: 共有1846条查询结果,搜索用时 15 毫秒
51.
Evaluation of a Flexible Endoscope for Laparoscopy 总被引:1,自引:0,他引:1
ROBERT A. SANOWSKI M.D. F.A.C.G. RICHARD A. KOZAREK M.D. EDWARD K. PARTYKA M.D. 《The American journal of gastroenterology》1981,76(5):416-419
Thirty patients underwent diagnostic laparoscopy using an unmodified Olympus GIF-P2 fiberendoscope. Both feasibility and safety of the fiberoptic instrument were evaluated. Compared to conventional laparoscopy, a greater area of the peritoneal cavity was visualized, and biopsies and photographs were successfully obtained. There were neither mechanical nor infectious complications. As has occurred in other areas of endoscopy, use a flexible instrument for laparoscopy appears to offer advantages over conventional rigid laparoscopes. 相似文献
52.
Summary. Peripheral blood stem cell autografts for the treatment of chronic myeloid leukaemia (CML) are currently under evaluation. A patient with CML received intensive chemotherapy followed by granulocyte colony-stimulating factor prior to the collection of peripheral blood derived stem cells. He developed unusually severe, and fatal, hypophosphataemia and this coincided with the rapid rise of his peripheral blood white cell count. The hypophosphataemia was considered to be due to a combination of severe anorexia, sepsis and the rapid growth factor-stimulated myeloid regeneration in CML. 相似文献
53.
Circulating Megakaryocytes and Platelet Release in the Lung 总被引:8,自引:1,他引:8
1. Megakaryocytes were demonstrated in central venous blood of each of23 patients who underwent cardiac catheterization. Cell counts ranged from0.7 to 5.9 megakaryocytes per ml. of blood; the equivalent of one-third ofthese cells were considered to contain a full complement of cytoplasm. It hasbecome evident that megakaryocytes are normal constituents of blood.2. In an attempt to quantify megakaryocyte migration from the bone marrow it was calculated that from 20-50 per cent of the mature megakaryocytepopulation enters the blood and ultimately reaches the lungs. The possibilitythat all megakaryocytes migrate from the marrow is not precluded with certainty by these studies.3. It was estimated that from 7-17 per cent of the bodys platelets are released in the pulmonary capillaries. If all megakaryocytes migrate from thebone marrow, then as much as 33 per cent of the platelet population is delivered to the blood in the lungs. Submitted on January 15, 1965 Accepted on March 13, 1965 相似文献
54.
A method for the preparation of I131-labeled anti-D eluates (I[unknown] anti-D)specific for the D antigen by adsorption and elution from intact D positivered cells is presented. A standard D antigen reference system for the quantitative comparison of the red cell D antigen from various donors was developedon the basis of kinetic studies of the effect of pH, temperature and antigenconcentration on the I[unknown] anti-D reaction with the D antigen. The red cell Dantigen determinations of the blood from 33 Negro and 102 Caucasiandonors showed wide monomodal frequency distributions which indicate aheterogeneity of quantitative D antigen reactivity consistent with previousserologic and I131-labeled anti-D studies. The average red cell D antigenreactivity of the 20 probable D homozygote and 14 established D hemizygoteCaucasian donors was similar to the D antigen reactivity of the 102 randomCaucasian donors. The red cell D antigen reactivity was strongly depressedby the C antigen (or C gene) in Caucasian bloods and enhanced by the Eantigen (or E gene) in Negro bloods. The E antigen (or E gene) may alsohave enhanced the D antigen reactivity in red cells from Caucasian donors,but the difference in D zygosity provides an alternative explanation for theresults. The marked influence on red cell D antigen reactivity in the presenceof the C and E antigen may well have obscured any lesser influence of Dzygosity. Accepted on December 6, 1962 相似文献
55.
Efficacy of a nicotine nasal spray in smoking cessation: a placebo-controlled, double-blind trial 总被引:1,自引:0,他引:1
NINA G. SCHNEIDER RICHARD OLMSTEAD FRENY VAGHAIWALLA MODY KIM DOAN MIKAEL FRANZON MURRAY E. JARVIK CRAIG STEINBERG 《Addiction (Abingdon, England)》1995,90(12):1671-1682
Laboratory trials have demonstrated the efficacy of nicotine replacement in smoking cessation bur absolute success races are low. For many, nicotine gum is hard to use and transdermal nicotine is slow-acting and passive. A new, faster-acting nicotine nasal spray (NNS) can provide easily self-administered relief from cigarette withdrawal. The NNS was tested for safely and efficacy in smoking cessation. Two hundred and fifty-five smokers were randomized to NNS or a piperine placebo. Drug use was limited to 8–32 doses/day for 6 months. Subjects were tested while smoking and at post-cessation daily (week 1) with follow-up at weeks 2, 3, 6 and at 3 months, 6 months and 1 year. Continuous abstinence analyses (CO ≤8 ppm.; no slips) showed that NNS significantly enhanced success rates over placebo overall (p < 0.001) and at all test intervals. Differences at key intervals between active and placebo were: 63% vs. 40% (day 5), 51% vs. 30% (week 3), 43% vs. 20% (6 weeks), 34% vs. 13% (3 months), 25% vs. 10% (6 months) and 18% vs. 8% (1 year). Side effects were common but tolerable. Cotinine measures showed that replacement of nicotine approximated 30% of smoking levels. Hazard functions revealed relapse risks peaked at day 1, day 5 and 3 weeks for strict abstinence. It is concluded NNS is safe, efficacious and a viable alternative treatment for smoking cessation. 相似文献
56.
JACQUES M.T. DE BARKER Ph.D. RICHARD N.W. HAUER M.D. PATRICIA F.A. BAKKER M.D. ANTON E. BECKER M.D. MICHIEL J. JANSE M.D. ETIENNE O. ROBLES DE MEDINA M.D. 《Journal of cardiovascular electrophysiology》1994,5(4):335-344
Abnormal Automaticity in Human Atrium, introduction: A 32-year-old woman was operated upon because of drug refractory atrial tachycardia.
Methods and Results: Electrophysiologic study was performed prior to operation. During surgery, epicardial mapping of the electrical activity of the left atrium was performed. The left atrial appendage was resected and studied in a tissue bath. Thereafter, histologic examination was performed. Polarity of the P wave in the surface ECG suggested that the tachycardia originated high in the left atrium. Epicardial mapping disclosed earliest activation in the apex of the left atrial appendage. Intracellular recordings from surgical specimen made at the site of origin, which was marked during surgery, revealed cells with phase 4 depolarization at cycle lengths ranging from 360 to 540 msec. Exit block prevented spread of activation from the spontaneously firing cells to surrounding tissue. Histology showed that spontaneous activity arose in an area with abnormal cells-characterized by an amorphous, pale eosinophilic staining cytoplasm and absence of nuclei-surrounded by normal myocytes.
Conclusion: The observations indicate that the mechanism of the atrial tachycardia was based on abnormal automaticity in an area consisting of a conglomeration of normal and abnormal myocytes. 相似文献
Methods and Results: Electrophysiologic study was performed prior to operation. During surgery, epicardial mapping of the electrical activity of the left atrium was performed. The left atrial appendage was resected and studied in a tissue bath. Thereafter, histologic examination was performed. Polarity of the P wave in the surface ECG suggested that the tachycardia originated high in the left atrium. Epicardial mapping disclosed earliest activation in the apex of the left atrial appendage. Intracellular recordings from surgical specimen made at the site of origin, which was marked during surgery, revealed cells with phase 4 depolarization at cycle lengths ranging from 360 to 540 msec. Exit block prevented spread of activation from the spontaneously firing cells to surrounding tissue. Histology showed that spontaneous activity arose in an area with abnormal cells-characterized by an amorphous, pale eosinophilic staining cytoplasm and absence of nuclei-surrounded by normal myocytes.
Conclusion: The observations indicate that the mechanism of the atrial tachycardia was based on abnormal automaticity in an area consisting of a conglomeration of normal and abnormal myocytes. 相似文献
57.
LAWRENCE SHERMAN M.D. SADASHIV S. SHENOY M.D. † SATEESH K. SATCHIDANAND M.D. ‡ PETER R. NEUMANN M.D. GEORGE G. BARRIOS M.D. RICHARD M. PEER M.D. 《The American journal of gastroenterology》1979,72(2):160-164
Of the multitude of sources capable of producing massive hemorrhage from the gastrointestinal tract, one of the rarest forms is arteriovenous malformation (AVM) of the stomach. The typical patient is a middle-aged male who presents with recurrent painless massive hematemesis and an unremarkable past medical history. Until recently the diagnostic work-up has often presented a dilemma, with the lesion rarely being confirmed prior to laparotomy. The patient whom we have encountertd with AVM of the stomach confirms our belief in the use of visceral angiography as a vital tool in the diagnosis of obscure gastrointestinal bleeding. We present this case as one which is unusual in its diagnostic work-up, therapeutic approach and pathologic findings. 相似文献
58.
YUKO UCHIMURA‐MAKITA M.D. YUKIKO NAKANO M.D. Ph.D. TAKEHITO TOKUYAMA M.D. MAI FUJIWARA M.D. YOSHIKAZU WATANABE M.D. AKINORI SAIRAKU M.D. HIROSHI KAWAZOE M.D. HIROYA MATSUMURA M.D. NOZOMU ODA M.D. HIROKI IKANAGA M.D. CHIKAAKI MOTODA M.D. KENTA KAJIHARA M.D. Ph.D. NOBORU ODA M.D. Ph.D. RICHARD L. VERRIER Ph.D. YASUKI KIHARA M.D. Ph.D. 《Journal of cardiovascular electrophysiology》2014,25(9):1021-1027
59.
SANGHAMITRA MOHANTY M.D. M.S. F.H.R.S. PRASANT MOHANTY M.B.B.S. M.P.H. LUIGI DI BIASE M.D. Ph.D. F.H.R.S. RONG BAI M.D. F.H.R.S. CHINTAN TRIVEDI M.D. M.P.H. PASQUALE SANTANGELI M.D. FRANCESCO SANTORO M.D. RICHARD HONGO M.D. STEVEN HAO M.D. SALWA BEHEIRY R.N. DAVID BURKHARDT M.D. JOSEPH G. GALLINGHOUSE M.D. RODNEY HORTON M.D. JAVIER E. SANCHEZ M.D. SHANE BAILEY M.D. PATRICK M. HRANITZKY M.D. JASON ZAGRODZKY M.D. ANDREA NATALE M.D. F.H.R.S. F.E.S.C. F.A.C.C. 《Journal of cardiovascular electrophysiology》2014,25(9):930-938
60.
JOY DOWNTON JOHN DENT RICHARD HEDDLE JAMES TOOULI PETER J. BUCKLE A. MALCOLM MACKINNON J. BRYANT WYMAN 《Journal of gastroenterology and hepatology》1987,2(4):317-324
The aim of this study was to investigate the hypothesis that the prolonged and substantial elevation of gastric pH which can be achieved with the antisecretory agent omeprazole will result in healing of peptic oesophagitis. Eight patients with erosive or ulcerative peptic oesophagitis were treated with omeprazole (30 mg daily) for 8 weeks. Complete healing occurred in seven patients after 8 weeks of omeprazole therapy. Only a small area of residual ulceration persisted in one unhealed patient. Heartburn resolved within the first 2 weeks of therapy in all but one patient. Specific food intolerances also were eliminated in most cases. Post-prandial oesophageal pH monitoring during omeprazole administration showed abolition of acid reflux episodes (pH < 4). This effect appeared to be due solely to the antisecretory effect of omeprazole, since motility measurements demonstrated a continued high frequency of reflux while concurrent gastric pH monitoring showed sustained elevation of gastric pH above 4. These results support the hypothesis that a prolonged and potent inhibition of gastric acid secretion renders refluxed gastric juice sufficiently innocuous to allow healing of severe peptic oesophagitis. 相似文献