全文获取类型
收费全文 | 548篇 |
免费 | 52篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 12篇 |
妇产科学 | 7篇 |
基础医学 | 45篇 |
口腔科学 | 11篇 |
临床医学 | 35篇 |
内科学 | 76篇 |
皮肤病学 | 5篇 |
神经病学 | 9篇 |
特种医学 | 168篇 |
外科学 | 195篇 |
综合类 | 5篇 |
预防医学 | 9篇 |
眼科学 | 1篇 |
药学 | 24篇 |
肿瘤学 | 13篇 |
出版年
2018年 | 4篇 |
2016年 | 9篇 |
2015年 | 12篇 |
2014年 | 9篇 |
2013年 | 4篇 |
2012年 | 10篇 |
2011年 | 11篇 |
2010年 | 16篇 |
2009年 | 16篇 |
2008年 | 30篇 |
2007年 | 45篇 |
2006年 | 20篇 |
2005年 | 15篇 |
2004年 | 10篇 |
2003年 | 7篇 |
2002年 | 22篇 |
2001年 | 26篇 |
2000年 | 17篇 |
1999年 | 23篇 |
1998年 | 31篇 |
1997年 | 19篇 |
1996年 | 9篇 |
1995年 | 11篇 |
1994年 | 17篇 |
1993年 | 10篇 |
1992年 | 6篇 |
1991年 | 17篇 |
1990年 | 8篇 |
1989年 | 16篇 |
1988年 | 15篇 |
1987年 | 10篇 |
1986年 | 13篇 |
1985年 | 17篇 |
1984年 | 15篇 |
1983年 | 8篇 |
1982年 | 8篇 |
1980年 | 6篇 |
1979年 | 6篇 |
1978年 | 11篇 |
1977年 | 8篇 |
1976年 | 14篇 |
1975年 | 7篇 |
1974年 | 4篇 |
1973年 | 2篇 |
1971年 | 4篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1968年 | 2篇 |
1967年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有620条查询结果,搜索用时 11 毫秒
51.
52.
Lord BI; Woolford LB; Wood LM; Czaplewski LG; McCourt M; Hunter MG; Edwards RM 《Blood》1995,85(12):3412-3415
BB-10010 is a genetically engineered variant of human macrophage inflammatory protein-1 alpha with improved solution properties. We show here that it mobilizes stem cells into the peripheral blood. We investigated the mobilizing effects of BB-10010 on the numbers of circulating 8-day spleen colony-forming units (CFU-S8), CFU-S12, and progenitors with marrow repopulating ability (MRA). A single subcutaneous dose of BB-10010 caused a twofold increase in circulating numbers of CFU-S8, CFU-S12, and MRA 30 minutes after dosing. We also investigated the effects of granulocyte colony-stimulating factor (G- CSF) and the combination of G-CSF with BB-10010 on progenitor mobilization. Two days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA progenitors by 25.7-, 19.8-, and 27.7-fold. A single administration of BB-10010 after 2 days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA even further to 38-, 33-, and 100- fold. Splenectomy resulted in increased circulating progenitor numbers but did not change the pattern of mobilization. Two days of treatment with G-CSF then increased circulating CFU-S8, CFU-S12, and MRA by 64-, 69-, and 32-fold. A single BB-10010 administration after G-CSF treatment further increased them to 85-, 117-, and 140-fold, respectively, compared with control. We conclude that BB-10010 causes a rapid increase in the number of circulating hematopoietic progenitors and further enhances the numbers induced by pretreatment with G-CSF. BB- 10010 preferentially mobilized the more primitive progenitors with marrow repopulating activity, releasing four times the number achieved with G-CSF alone. Translated into a clinical setting, this improvement in progenitor cell mobilization may enhance the efficiency of harvest and the quality of grafts for peripheral blood stem cell transplantation. 相似文献
53.
Role of listeriolysin O in cell-to-cell spread of Listeria monocytogenes 总被引:13,自引:0,他引:13 下载免费PDF全文
Listeria monocytogenes is a facultative intracellular bacterial pathogen that escapes from a host vacuolar compartment and grows rapidly in the cytosol. Listeriolysin O (LLO) is a secreted pore-forming protein essential for the escape of L. monocytogenes from the vacuole formed upon initial internalization. However, its role in intracellular growth and cell-to-cell spread events has not been testable by a genetic approach. In this study, purified six-His-tagged LLO (HisLLO) was noncovalently coupled to the surface of nickel-treated LLO-negative mutants. Bound LLO mediated vacuolar escape in approximately 2% of the mutants. After 5.5 h of growth, cytosolic bacteria were indistinguishable from wild-type bacteria with regard to formation of pseudopod-like extensions, here termed listeriopods, and spread to adjacent cells. However, bacteria in adjacent cells failed to multiply and were found in double-membrane vacuoles. Addition of bound LLO to mutants lacking LLO and two distinct phospholipases C (PLCs) also resulted in spread to adjacent cells, but these triple mutants became trapped in multiple-membrane vacuoles that are reminiscent of autophagocytic vacuoles. These studies show that neither LLO nor the PLCs are necessary for listeriopod formation and uptake of bacteria into neighboring cells but that LLO is required for the escape of L. monocytogenes from the double-membrane vacuole that forms upon cell-to-cell spread. 相似文献
54.
下消化道出血221例分析 总被引:2,自引:2,他引:2
0 引言 下消化道出血是消化科的常见病 ,是指十二指肠空肠移行部 ,屈氏韧带以下的小肠和大肠疾病引起的肠道出血 .有人认为一般不包括痔和肛裂出血 [1 ] .临床最常见为慢性出血 ,但有时出血量大危及生命 ,需要做紧急处理 ,现将我院1992 - 0 1/ 1999- 0 8门诊及病房收治的 2 2 1例下消化道出血进行分析 ,报告如下 :1 临床资料 男 12 0例 ,女 10 1例 ,年龄 14~ 72 (平均 42 )岁 ,病程 16 h~ 10 a.患者分别以脓血便、暗红色血便、鲜血便或果酱色血便为主诉前来就诊 ,其中有休克症状的大出血者6例 .血 Hb<110 g·L- 1 40例 ,<80 g·L- 1… 相似文献
55.
BACKGROUND: Systemic hypertension affects many allograft recipients, is an important risk factor for chronic graft dysfunction, and is linked to reduced graft survival. The condition may up-regulate the expression of inflammatory host cells and their products. These, in turn, may significantly injure vascular endothelium and other components of allografted kidneys. METHODS: Lewis rats received orthotopic F344 renal allografts, a standard model of chronic rejection. Renovascular hypertension was produced by placing a silver clip (0.25 mm) on the renal artery of the retained contralateral native kidney 4 weeks after transplantation. Sham-clipped rats served as normotensive controls. Four recipient groups (Gp) were studied: Gp 1, rats with an allograft plus a clipped native kidney; Gp 2, those with an allograft and a sham-clipped native kidney; Gp 3, isografted animals with a clipped native kidney; and Gp 4, those bearing an isograft and a sham-clipped native kidney. Systolic blood pressure and proteinuria were measured every 2 weeks for 24 weeks. Grafts were assessed serially for morphologic and immunohistologic changes. RESULTS: Systemic blood pressure rose to hypertensive levels in Gps 1 and 3 within a week of clipping but never increased in Gps 2 and 4. Proteinuria developed in hypertensive animals but remained at baseline in normotensive controls. Intimal thickening of allograft arteries progressed to luminal obliteration with extensive perivascular and interstitial fibrosis by 24 weeks. In contrast, vascular changes in isografts of hypertensive hosts were restricted to medial hypertrophy. Tumor necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta, platelet derived growth factor (PDGF), endothelin, Il-6, major histocompatibility complex (MHC) class II, and B7 were up-regulated in allografts in hypertensive hosts. Vascular deposition of immunoglobulin (IgG) was increased. These changes were markedly less pronounced in Gp 3 isografts and minimal in the kidneys of the normotensive animals of Gps 2 and 4. CONCLUSIONS: An experimental model is presented that examines the influence of recipient hypertension in the pathogenesis of chronic dysfunction and injury developing in rat renal allografts over time. 相似文献
56.
Boston has played a significant role in the development of renal transplantation. In Boston was performed the first successful isograft between identical twins (1954) the first successful allograft between fraternal twins (1959) and the first successful allograft from a cadaveric donor (1962). An immunosuppressive drug was also described in Boston by hematologists Schwartz and Dameschek (1959) and modified for renal transplantation in dogs (1961) and used for the first time in a human recipient in March 1962. By 1965 renal transplantation had become a clinical reality. Three hundred and ninety-eight of 589 recipients (68%) since 1950 are still alive, a remarkable figure considering that it includes all the earliest experimental transplants. One hundred and ninety-five of 295 (68%) with living-related donor transplants still have functioning allografts; 104/265 (39%) with cadaveric donor transplants have functioning grafts currently. Since 1968 transplants from living-related donors have an 80% one year survival whereas cadaveric donor transplants have approximately a 50% one year survival. Seventy-nine per cent of all one year survivors have had excellent psycho-social rehabilitation. 相似文献
57.
Intratemporal vascular tumors: detection with CT and MR imaging 总被引:1,自引:0,他引:1
Lo WW; Shelton C; Waluch V; Solti-Bohman LG; Carberry JN; Brackmann DE; Wade CT 《Radiology》1989,171(2):445-448
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion. 相似文献
58.
K Tanaka L A Turka J W Kupiec-Weglinski E L Milford H Ueda T Diamantstein C B Carpenter N L Tilney 《Transplantation》1990,50(1):125-131
Although the ability of Ts to prevent allograft rejection has been well established, their intrinsic characteristics and dependence upon lymphokines remain poorly defined. The cells from unmodified LEWxBN bulk 5-day rat MLR inhibit both proliferation in test MLR and generation of CTL, as well as prolonging the survival of donor-specific test cardiac allografts following adoptive transfer. We have examined the effects of a panel of mAb directed against functionally distinct epitopes on the p55 subunit of rat IL-2R on the generation and in vitro/in vivo activity of MLR-generated Ts. ART-18 (which blocks IL-2-dependent T cell growth) was the only mAb from the panel that profoundly suppressed alloreactive T cell proliferation in primary MLR (47.5%). However, the generation of Ts was never affected by any mAb (% suppression in test MLR = 40-60%). Neither ART-18 nor ART-65 (which does not affect T cell proliferation) interfered with the efficacy of Ts to inhibit CTL generation in fresh bulk MLR. Adoptive transfer of cells (3-10 x 10(6] from ART-18 or ART-65-modulated MLR into naive LEW rats prolonged (LEW x BN)F1 test cardiac allograft survival to 11-13 days (P less than 0.05 as compared with acutely rejecting hosts). All in vitro and in vivo effects exerted by MLR-generated cells were antigen-specific. In unmodified MLR, Ts were IL-2R+ (ca. 50% of total blasts), as shown by cell separation using magnetic beads. In contrast, in MLR with ART-18 added, Ts were primarily IL-2R- (ca. 10% of blasts). Thus, antirat p55 subunit IL-2R mAb do not inhibit MLR-generated Ts functionally operative in vitro and in vivo. IL-2R- Ts precursors requiring lymphokine(s) other than IL-2 may differentiate into IL-2-dependent Ts effectors. Such divergent IL-2 requirements for Ts growth in vitro may explain the Ts-sparing effects in allograft recipients treated with anti-IL-2R mAb. 相似文献
59.
60.
LG Essen 《MedR Medizinrecht》2002,20(6):311-313
Ohne Zusammenfassung 相似文献