首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2994篇
  免费   165篇
  国内免费   31篇
耳鼻咽喉   30篇
儿科学   106篇
妇产科学   26篇
基础医学   466篇
口腔科学   81篇
临床医学   339篇
内科学   897篇
皮肤病学   120篇
神经病学   66篇
特种医学   273篇
外科学   226篇
综合类   55篇
预防医学   141篇
眼科学   124篇
药学   184篇
中国医学   2篇
肿瘤学   54篇
  2018年   27篇
  2016年   30篇
  2015年   33篇
  2014年   31篇
  2013年   86篇
  2012年   47篇
  2011年   50篇
  2010年   62篇
  2009年   46篇
  2008年   51篇
  2007年   72篇
  2006年   90篇
  2005年   71篇
  2004年   71篇
  2003年   74篇
  2002年   75篇
  2001年   83篇
  2000年   98篇
  1999年   91篇
  1998年   94篇
  1997年   110篇
  1996年   113篇
  1995年   82篇
  1994年   83篇
  1993年   79篇
  1992年   65篇
  1991年   46篇
  1990年   43篇
  1989年   79篇
  1988年   63篇
  1987年   56篇
  1986年   60篇
  1985年   44篇
  1984年   56篇
  1983年   30篇
  1982年   32篇
  1981年   37篇
  1980年   53篇
  1979年   27篇
  1978年   27篇
  1977年   37篇
  1976年   41篇
  1975年   38篇
  1972年   27篇
  1965年   50篇
  1964年   50篇
  1963年   47篇
  1962年   42篇
  1961年   40篇
  1960年   65篇
排序方式: 共有3190条查询结果,搜索用时 15 毫秒
101.
Ball  ED; Mills  LE; Coughlin  CT; Beck  JR; Cornwell  GG d 《Blood》1986,68(6):1311-1315
Second or third chemotherapy-induced remissions in acute myelogenous leukemia (AML) are limited by early relapse of the leukemia. We developed monoclonal antibodies (MoAbs) that are cytotoxic to myeloid leukemia cells to treat bone marrow from these patients ex vivo for autologous transplantation. In this pilot study, bone marrow was harvested from ten patients with AML in remission, treated with one or two complement-fixing MoAbs, PM-81 and AML-2-23, which react with myeloid differentiation antigens, incubated with rabbit complement, and cryopreserved. These MoAbs were chosen because they have broad reactivity with AML cells but not with pluripotent progenitor cells. At the time of transplant, 6 patients were in second complete remission, 1 each was in third complete or partial remission, and 2 were in early first relapse. The patients were treated with cyclophosphamide (60 mg/kg a day for 2 days) and total body irradiation (200 cGy twice a day for 3 days) and given infusions of MoAb-treated bone marrow. Full bone marrow reconstitution was observed in eight patients; two patients did not recover platelets. Seven of the ten patients are surviving and disease-free at 21.0, 15.0, 13.0, 10.0, 6.0, 3.0, and 2.0 months posttransplant. Treating bone marrow with MoAbs to myeloid differentiation antigens does not interfere with pluripotential stem cell engraftment. Longer follow-up and a controlled study are necessary to prove that the apparent efficacy of this therapeutic approach in some patients is attributable to MoAb-mediated killing of leukemia cells.  相似文献   
102.
Using accepted diagnostic criteria we have selected, for study, 160 patients with Crohn's disease involving the colon. There is a remarkable discrepancy between the clinical diagnosis prior to or at the time of initial admission to this hospital and the diagnosis following definitive investigation and observation of the progression of disease.
The peak age incidence occurred in the second decode The colitis group showed a greater percentage of patients over 30 years of age. Although histopathology was not obtained in all patients, there appeared to be sparing of the ascending colon in a small percentage (9%) of patients with ileocolitis.
Comparison of the clinical features of granulomatous disease limited to the colon and granulomatous ileocolitis shows a significantly greater incidence of extraintestinal symptoms and overt bleeding in the former. Nausea, vomiting, subacute obstruction, abdominal mass and internal fistulas were substantially more common in ileocolitis but the difference was not statistically significant. In this series retroperitoneal abscess did not occur in patients with disease localized to the colon. In the 10 patients with ileocolitis who developed an abscess, however, the site of fistula was the colon in four patients. In one of these, the abscess was left-sided.  相似文献   
103.
104.
Stem Cell Migration and Proliferation During Severe Anemia   总被引:3,自引:2,他引:3  
The pluripotential stem cell (CFU) compartment of marrow and spleen wasevaluated in mice subjected to an intense erythroid stimulus associated withphenylhydrazine-induced anemia. Erythroid hyperplasia occurred in both marrow and spleen. CFU in the marrowgradually declined to approximately 50per cent of control levels (day 5) whiletheir numbers in the spleen increased(fourfold) by day 3 and were maintainedat this level for several days. Thesechanges in numbers of marrow andsplenic CFU were not associated withCFU proliferation. Thereafter, CFU inthe marrow, but not in the spleen, entered active cell cycle. The data suggestthat CFU migrate from marrow to spleenduring the demands of severe anemia.The induction of marrow CFU into cyclefurther suggests a negative feedback,which, perhaps through cell-cell interaction, maintains stem cells at a criticalcompartment size. The failure of splenicCFU to cycle may reflect the converseeffect, i.e. an inhibition on stem cell proliferation in the wake of an expandedstem cell pool.

Submitted on March 17, 1970 Revised on May 14, 1970 Accepted on June 9, 1970  相似文献   
105.
Factor V deficiency has been identified in 8 of 8 patients 7--20 yr of age, with Philadelphia-positive (Ph1+) chronic myelogenous leukemia (CML). In these 8 patients, factor V deficiency was not due to hepatic dysfunction, factor V inhibitors, or disseminated intravascular coagulation. In 3 patients, factor V activity rose 10%--12% (0.10--0.12 U/ml) after the infusion of 28--31 ml/kg body weight of fresh frozen plasma (FFP). The rise persisted less than 14 hr. The mean measured postinfusion rise in factor V was 18% of the expected rise calculated from the volume of FFP infused in the patients' plasma volume. In 4 patients, a small transient rise in factor V activity occurred after splenectomy or plateletpheresis. Factor V deficiency was completely corrected after a marked reduction in bone marrow cellularity in 2 patients with Ph1+ CML treated with extensive chemotherapy, total body irradiation, and bone marrow transplantation. Factor V deficiency was retrospectively observed in 6 of 20 patients, ages 20--80 yr, with Ph1+ CML and 3 of 6 patients with other myeloproliferative disorders. The factor V deficiency appears to be associated with the large myeloid- megakaryocytic cell mass characteristic of CML and other myeloproliferative disorders.  相似文献   
106.
107.
Heart failure (HF) constitutes the growing cardiovascular burden and the major public health issue, but comprehensive statistics on HF epidemiology and related management in Europe are missing. The Heart Failure Association (HFA) Atlas has been initiated in 2016 in order to close this gap, representing the continuity directly rooted in the European Society of Cardiology (ESC) Atlas of Cardiology. The major aim of the HFA Atlas is to establish a contemporary dataset on HF epidemiology, resources and reimbursement policies for HF management, organization of the National Heart Failure Societies (NHFS) and their major activities, including education and HF awareness. These data are gathered in collaboration with the network of NHFS of the ESC member and ESC affiliated countries. The dataset will be continuously improved and advanced based on the experience and enhanced understanding of data collection in the forthcoming years. This will enable revealing trends, disparities and gaps in knowledge on epidemiology and management of HF. Such data are highly needed by the clinicians of different specialties (aside from cardiologists and cardiac surgeons), researchers, healthcare policy makers, as well as HF patients and their caregivers. It will also allow to map the snapshot of realities in HF care, as well as to provide insights for evidence‐based health care policy in contemporary management of HF. Such data will support the ESC/HFA efforts to improve HF management ant outcomes through stronger recommendations and calls for action. This will likely influence the allocation of funds for the prevention, treatment, education and research in HF.  相似文献   
108.
109.
Cardiogenic shock (CS) is a complex multifactorial clinical syndrome with extremely high mortality, developing as a continuum, and progressing from the initial insult (underlying cause) to the subsequent occurrence of organ failure and death. There is a large spectrum of CS presentations resulting from the interaction between an acute cardiac insult and a patient's underlying cardiac and overall medical condition. Phenotyping patients with CS may have clinical impact on management because classification would support initiation of appropriate therapies. CS management should consider appropriate organization of the health care services, and therapies must be given to the appropriately selected patients, in a timely manner, whilst avoiding iatrogenic harm. Although several consensus‐driven algorithms have been proposed, CS management remains challenging and substantial investments in research and development have not yielded proof of efficacy and safety for most of the therapies tested, and outcome in this condition remains poor. Future studies should consider the identification of the new pathophysiological targets, and high‐quality translational research should facilitate incorporation of more targeted interventions in clinical research protocols, aimed to improve individual patient outcomes. Designing outcome clinical trials in CS remains particularly challenging in this critical and very costly scenario in cardiology, but information from these trials is imperiously needed to better inform the guidelines and clinical practice. The goal of this review is to summarize the current knowledge concerning the definition, epidemiology, underlying causes, pathophysiology and management of CS based on important lessons from clinical trials and registries, with a focus on improving in‐hospital management.  相似文献   
110.
Bartonella henselae is associated with a wide spectrum of clinical manifestations, including cat scratch disease, endocarditis and meningoencephalitis, in immunocompetent and immunocompromised patients. We report the first molecularly confirmed case of B. henselae infection in an AIDS patient in state of Rio de Janeiro, Brazil. Although DNA sequence of B. henselae has been detected by polymerase chain reaction in a lymph node biopsy, acute and convalescent sera were nonreactive.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号