全文获取类型
收费全文 | 3752篇 |
免费 | 321篇 |
国内免费 | 149篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 123篇 |
妇产科学 | 50篇 |
基础医学 | 495篇 |
口腔科学 | 40篇 |
临床医学 | 430篇 |
内科学 | 844篇 |
皮肤病学 | 77篇 |
神经病学 | 339篇 |
特种医学 | 397篇 |
外科学 | 288篇 |
综合类 | 68篇 |
预防医学 | 382篇 |
眼科学 | 92篇 |
药学 | 266篇 |
2篇 | |
中国医学 | 1篇 |
肿瘤学 | 314篇 |
出版年
2021年 | 26篇 |
2019年 | 52篇 |
2018年 | 56篇 |
2017年 | 33篇 |
2016年 | 40篇 |
2015年 | 61篇 |
2014年 | 44篇 |
2013年 | 124篇 |
2012年 | 142篇 |
2011年 | 152篇 |
2010年 | 119篇 |
2009年 | 114篇 |
2008年 | 141篇 |
2007年 | 244篇 |
2006年 | 133篇 |
2005年 | 151篇 |
2004年 | 109篇 |
2003年 | 106篇 |
2002年 | 116篇 |
2001年 | 121篇 |
2000年 | 100篇 |
1999年 | 111篇 |
1998年 | 115篇 |
1997年 | 107篇 |
1996年 | 100篇 |
1995年 | 81篇 |
1994年 | 60篇 |
1993年 | 75篇 |
1992年 | 69篇 |
1991年 | 83篇 |
1990年 | 99篇 |
1989年 | 116篇 |
1988年 | 91篇 |
1987年 | 74篇 |
1986年 | 81篇 |
1985年 | 79篇 |
1984年 | 64篇 |
1983年 | 55篇 |
1982年 | 37篇 |
1981年 | 40篇 |
1980年 | 42篇 |
1979年 | 51篇 |
1978年 | 32篇 |
1977年 | 41篇 |
1976年 | 55篇 |
1975年 | 43篇 |
1974年 | 27篇 |
1973年 | 23篇 |
1972年 | 24篇 |
1971年 | 26篇 |
排序方式: 共有4222条查询结果,搜索用时 15 毫秒
131.
Proliferation of myeloid progenitor cells in human long-term bone marrow cultures is stimulated by interleukin-1 beta 总被引:3,自引:0,他引:3
Fibbe WE; Goselink HM; Van Eeden G; Van Damme J; Billiau A; Voogt PJ; Willemze R; Falkenburg JH 《Blood》1988,72(4):1242-1247
To study the effect of interleukin-1 (IL-1) beta on the proliferation of hematopoietic progenitor cells (HPC) in long-term bone marrow cultures (LTBMC), stromal cell layers were established from normal human bone marrow. Autologous cryopreserved mononuclear phagocyte- and T-lymphocyte-depleted bone marrow cells were reinoculated on the stromal layers in fresh culture medium, with or without the addition of human IL-1 beta (30 U/mL). Once a week, half of the culture supernatant was replaced with fresh culture medium with or without IL-1, and all nonadherent cells were returned to the flasks. At weekly intervals during a period of 5 weeks, one culture was sacrificed to determine the total number of cells and hematopoietic progenitor cells, present in the adherent and the nonadherent cell fractions. In IL-1-stimulated cultures, the number of cells recovered during a period of 5 weeks exceeded the number of cells in unstimulated control cultures by 1.5 times. This difference was attributed to a twofold increase in the number of adherent cells. The number of HPC recovered from IL-1- stimulated cultures was not different from that recovered from controls. The levels of colony-stimulating activity (CSA) in supernatants from IL-1-stimulated cultures were significantly higher than those in supernatants from control cultures. These results indicate that IL-1 enhances the recovery of cells in LTBMC by stimulating the proliferation of HPC with the concurrent release of CSA from stromal cells, without diminishing the number of HPC. 相似文献
132.
Weisdorf DJ; Verfaillie CM; Davies SM; Filipovich AH; Wagner JE Jr; Miller JS; Burroughs J; Ramsay NK; Kersey JH; McGlave PB 《Blood》1995,85(12):3452-3456
Delay in hematologic recovery after bone marrow transplantation (BMT) can extend and amplify the risks of infection and hemorrhage, compromise patients' survival, and increase the duration and cost of hospitalization. Because current studies suggest that granulocyte- macrophage (GM) colony-stimulating factor (CSF) may potentiate the sensitivity of hematopoietic progenitor cells to G-CSF, we performed a prospective, randomized trial comparing GM-CSF (250 micrograms/m2/d x 14 days) versus sequential GM-CSF x 7 days followed by G-CSF (5 micrograms/kg/d x 7 days) as treatment for primary or secondary graft failure after BMT. Eligibility criteria included failure to achieve a white blood cell (WBC) count > or = 100/microL by day +21 or > or = 300/microL by day +28, no absolute neutrophil count (ANC) > or = 200/microL by day +28, or secondary sustained neutropenia after initial engraftment. Forty-seven patients were enrolled: 23 received GM-CSF (10 unrelated, 8 related allogeneic, and 5 autologous), and 24 received GM- CSF followed by G-CSF (12 unrelated, 7 related allogeneic, and 5 autologous). For patients receiving GM-CSF alone, neutrophil recovery (ANC > or = 500/microL) occurred between 2 and 61 days (median, 8 days) after therapy, while those receiving GM-CSF+G-CSF recovered at a similar rate of 1 to 36 days (median, 6 days; P = .39). Recovery to red blood cell (RBC) transfusion independence was slow, occurring 6 to 250 days (median, 35 days) after enrollment with no significant difference between the two treatment groups (GM-CSF: median, 30 days; GM-CSF+G- CSF; median, 42 days; P = .24). Similarly, platelet transfusion independence was delayed until 4 to 249 days (median, 32 days) after enrollment, with no difference between the two treatment groups (GM- CSF: median, 28 days; GM-CSF+G-CSF: median, 42 days; P = .38). Recovery times were not different between patients with unrelated donors and those with related donors or autologous transplant recipients. Survival at 100 days after enrollment was superior after treatment with GM-CSF alone. Only 1 of 23 patients treated with GM-CSF died versus 7 of 24 treated with GM-CSF+G-CSF who died 16 to 84 days (median, 38 days) after enrollment, yielding Kaplan-Meier 100-day survival estimates of 96% +/- 8% for GM-CSF versus 71% +/- 18% for GM-CSF+G-CSF (P = .026). These data suggest that sequential growth factor therapy with GM-CSF followed by G-CSF offers no advantage over GM-CSF alone in accelerating trilineage hematopoiesis or preventing lethal complications in patients with poor graft function after BMT.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
133.
Distribution of human herpesvirus-8 latently infected cells in Kaposi's sarcoma, multicentric Castleman's disease, and primary effusion lymphoma 总被引:3,自引:0,他引:3 下载免费PDF全文
Dupin N Fisher C Kellam P Ariad S Tulliez M Franck N van Marck E Salmon D Gorin I Escande JP Weiss RA Alitalo K Boshoff C 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(8):4546-4551
Human herpesvirus 8 (HHV-8, also called KSHV) is linked to the etiopathogenesis of Kaposi's sarcoma (KS), multicentric Castleman's disease (MCD), and primary effusion lymphoma (PEL). The universal presence of HHV-8 in early KS has not yet been shown. We used a mAb (LN53) against latent nuclear antigen-1 (LNA-1) of HHV-8 encoded by ORF73 to study the distribution of the cell types latently infected by HHV-8 in patch, plaque, and nodular KS, MCD, and PEL. In early KS, HHV-8 is present in <10% of cells forming the walls of ectatic vessels. In nodular KS, HHV-8 is present in cells surrounding slit-like vessels and in >90% of spindle cells, but not in normal vascular endothelium. In addition, HHV-8 colocalizes with vascular endothelial growth factor receptor-3 (VEGFR-3), a marker of lymphatic and precursor endothelium. In early KS lesions, VEGFR-3 is more extensively expressed than LNA-1, indicating that HHV-8 is not inducing the proliferation of VEGFR-3-positive endothelium directly. In MCD, HHV-8 is present in mantle zone large immunoblastic B cells. No staining for LNA-1 is seen in samples from multiple myeloma, prostate cancer, and angiosarcoma, supporting the absence of any etiological link between these diseases and HHV-8. 相似文献
134.
135.
136.
137.
Background
The kallikrein-kinin system (KKS) is an endogenous pathway involved in angiogenesis and tumourigenesis, both vital for cancer growth and progression.Objectives
To investigate the effect of two bradykinin receptor (B1R and B2R) agonists on growth and motility of prostate tumour (DU145) and micro-vascular endothelial cells (dMVECs).Methods
Increasing concentrations of selective B1R and B2R agonists were added to cultured cells. Cell proliferation and migration were assessed using the 3-[4,5 dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) and modified Boyden Chamber assays, respectively. Where significant stimulation was found, the influence of an antagonist was also investigated.Results
Neither growth nor motility of endothelial cells was affected by either agonist. In DU145 cells, while the B2R agonist was without any significant effect, the B1R agonist stimulated proliferation and migration at concentrations of 10nM and 50nM respectively. Further, this effect was abrogated when cells were pre-incubated with a B1R antagonist.Conclusions
Unlike the physiologically-active B2R, the pathologically-inducible B1R may be implicated in prostate tumourigenic events. The involvement of the KKS in malignant prostate pathology supports on-going exploration of bradykinin receptor antagonists as target candidates in the development of alternate approaches to cancer therapy. 相似文献138.
Linda J. Adams Judy Salmon Jennifer A. Donald Philip B. Mitchell Peter R. Schofield 《American journal of medical genetics. Part A》1996,67(5):485-487
To examine whether genes that predispose to schizophrenia also confer a predisposition to other psychiatric disorders such as bipolar affective disorder (BAD), we tested for linkage between the recently identified schizophrenia susceptibility locus D6S260 and the inheritance of BAD in 12 large Australian pedigrees. We found no evidence for linkage over a region of 12–27 cM from the D6S260 locus, depending on the model used. Our results therefore do not provide support for the continuum theory of psychosis. © 1996 Wiley-Liss, Inc. 相似文献
139.
Jane S. Paulsen David P. Salmon Andreas U. Monsch Nelson Butters Michael R. Swenson Mark W. Bondi 《Journal of clinical psychology》1995,51(1):48-58
This study compared the discriminative utility of problem-solving and memory tasks in patients with Alzheimer's and Huntington's disease and in age-, education-, and gender-matched normal control subjects. Problem-solving was assessed with a modified version of the Wisconsin Card Sorting Test. Memory was measured with a 10–item, 6-trial version of the Buschke Selective Reminding Test. Receiver Operating Characteristic curves were plotted to determine which measure provided the highest sensitivity (i.e., hit rate) and specificity (i.e., correct rejection rate). Both tests provided excellent detection of dementia (88 to 98% classification accuracy), but were less robust in differentiating between dementia groups. Findings underscore the suitability of both measures to detect mild dementia, but emphasize the importance of specific memory measures to differentiate between cortical and subcortical dementia. 相似文献
140.
Anke de Haan Markus A. Landolt Eiko I. Fried Kristian Kleinke Eva Alisic Richard Bryant Karen Salmon Sue-Huei Chen Shu-Tsen Liu Tim Dalgleish Anna McKinnon Alice Alberici Jade Claxton Julia Diehle Ramón Lindauer Carlijn de Roos Sarah L. Halligan Rachel Hiller Christian H. Kristensen Beatriz O.M. Lobo Nicole M. Volkmann Meghan Marsac Lamia Barakat Nancy Kassam-Adams Reginald D.V. Nixon Susan Hogan Raija-Leena Punamäki Esa Palosaari Elizabeth Schilpzand Rowena Conroy Patrick Smith William Yule Richard Meiser-Stedman 《Journal of child psychology and psychiatry, and allied disciplines》2020,61(1):77-87