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141.
多效唑(MET)对啤酒花试管苗生长和移栽的影响 总被引:5,自引:0,他引:5
在培养基中加入0.1-0.2mg/L浓度的多效唑(MET),啤酒花试管苗植株矮壮,单株生根数量增加、移栽成活率提高13%。0.5-2.0mg/L时,试管苗基部愈伤组织增多,枝叶失绿,生长受到抑制。初步发现多将唑对啤酒花试管苗的效力与葡萄糖用量呈正相关。 相似文献
142.
M. Bownes Thomas W. Cline Howard A. Schneiderman 《Development genes and evolution》1977,181(3):279-284
Summary
Daughterless is a temperature-sensitive, maternal effect mutation ofDrosophila melanogaster. Homozygousdaughterless females raised at temperatures above 22°C do not produce any female progeny. It was possible to rescue these female embryos by injecting cytoplasm from non-mutant unfertilized eggs into embryos fromdaughterless mothers. Cytoplasm from unfertilized eggs laid by homozygousdaughterless mothers was ineffective. Surprisingly, the cytoplasm from developing embryos with either wild-type ordaughterless mothers could also effect rescue. Based upon this data, we suggest that male and female embryos ofdaughterless mothers differ in their ability to initiate the synthesis of a product during the nuclear multiplication (cleavage) stage of embroniic development in the absence of a putativeda
+ maternally-synthesized factor, and that this is the basis for the sex-specific action of theda maternal effect. 相似文献
143.
G. Gopinath A. K. Mahapatra J. C. Bharadwaj R. Banerji D. N. Sharma P. N. Tandon 《Journal of biosciences》1989,14(3):255-260
A feasibility study of neural transplantation in adult rhesus monkey was undertaken. Fresh and preserved neocortex containing
multiplying and maturing neurons obtained from 55–70 gestation days were transplanted into the striatum, cerebellum and cerebral
cortex of adult monkeys. Tissues were preserved for 4 days either at subzero temperature in the freezer compartment of the
ordinary refrigerator in Ringer lactate or incubated in culture medium. While 2 monkeys out of 5 injected with preserved tissue
had successful transplants after 4 months, all the 10 monkeys injected with fresh tissue had no transplants. The size of the
two surviving transplants was small. The neurons in the transplants were mainly in clusters. Many of the cells were immature
and some showed early degenerative changes. Neuronal processes were restricted to the transplants and thus showed lack of
morphological integration with the host tissue. Further studies are in progress to define the nature of the embryonic tissue
of primate which can grow and survive and also the role of neural grafts in functional recovery following experimental lesions
of the brain regions. 相似文献
144.
Gerald Drews Kay Kohlhaw Daniel Palmes Petra Madaj-Sterba Thomas Hartwig Johann Hauss Hans-Ullrich Spiegel 《Journal of Experimental Animal Science》2000,41(3)
Sampling of rat hepatic tissue for histomorphological analysis is usually performed in two different ways: either by killing the animals or by minilaparotomy.In this study we describe a percutaneous core biopsy technique which has been used on day 7, 14 and 21 after allogeneic rat liver transplantation (DA → LEW) in order to examine grafts for rejection in different treatment groups. Fifty-two liver biopsies were performed in 24 animals using a 16-gauge intravenous cannula. Forty-five provided usable specimens which were sufficient for both light or electron microscopy and immunohistochemical analyses to determine the degree of graft rejection. In 7 cases (13.5%) sampling was unsuccessful, especially on day 21 after transplantation, as the plastic cannula could not penetrate the hardened tissue. In 3 animals (5.8%) puncture was immediately followed by death due to perforation of the diaphragm or ether intoxication.In conclusion, this technique is a reliable method for providing ample tissue samples from the rat liver with a low risk of complications. 相似文献
145.
146.
Micro‐vesicles derived from human Wharton's Jelly mesenchymal stromal cells mitigate renal ischemia‐reperfusion injury in rats after cardiac death renal transplantation 下载免费PDF全文
147.
Winnie Ip Juliana M.F. Silva Hubert Gaspar Arindam Mitra Shreenal Patel Kanchan Rao Robert Chiesa Persis Amrolia Kimberly Gilmour Gul Ahsan Mary Slatter Andrew R. Gennery Robert F. Wynn Paul Veys Waseem Qasim 《Cytotherapy》2018,20(6):830-838
Background
Adenovirus (ADV) reactivation can cause significant morbidity and mortality in children after allogeneic stem cell transplantation. Antiviral drugs can control viremia, but viral clearance requires recovery of cell-mediated immunity.Method
This study was an open-label phase 1/2 study to investigate the feasibility of generating donor-derived ADV-specific T cells (Cytovir ADV, Cell Medica) and to assess the safety of pre-emptive administration of ADV-specific T cells in high-risk pediatric patients after allogeneic hematopoietic stem cell transplantation (HSCT) to treat adenoviremia. Primary safety endpoints included graft-versus-host disease (GvHD), and secondary endpoints determined antiviral responses and use of antiviral drugs.Results
Between January 2013 and May 2016, 92 donors were enrolled for the production of ADV T cells at three centers in the United Kingdom (UK), and 83 products were generated from 72 mobilized peripheral blood harvests and 20 steady-state whole blood donations. Eight children received Cytovir ADV T cells after standard therapy and all resolved ADV viremia between 15 and 127 days later. ADV-specific T cells were detectable using enzyme-linked immunospot assay (ELISpot) in the peripheral blood of all patients analyzed. Serious adverse events included Grade II GvHD, Astrovirus encephalitis and pancreatitis.Conclusion
The study demonstrates the safety and feasibility of pre-emptively manufacturing peptide pulsed ADV-specific cells for high-risk pediatric patients after transplantation and provides early evidence of clinical efficacy. 相似文献148.
Nikolaos Zogas Garyfalia Karponi Fotios Iordanidis Stylianos Malasidis Vasilios Paraskevas Anastasia Papadopoulou Zaharias George Scouras Achilles Anagnostopoulos Evangelia Yannaki 《Cytotherapy》2018,20(1):149-164
Background aims
Acute graft-versus-host disease (aGVHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation, mediated by alloreactive donor T cells. Toll-like receptors (TLRs), a family of conserved pattern-recognition receptors (PRRs), represent key players in donors' T-cell activation during aGVHD; however, a regulatory, tolerogenic role for certain TLRs has been recognized in a different context. We investigated whether the ex vivo–induced TLR-2,-4,-7 tolerance in donor cells could prevent alloreactivity in a mismatched transplantation model.Methods
TLR-2,-4,-7 tolerance was induced in mouse splenocytes, after stimulation with low doses of corresponding ligands. Cellular and molecular changes of the TLR-tolerant splenocytes and purified T cells were assessed by immunophenotypic and gene expression analyses. Incidence of aGVHD was evaluated by the clinical score and survival as well as histopathology of target tissues.Results
Only the R848-induced TLR7 tolerance prevented aGVHD. The TLR7 ligand–induced tolerance lasted for a critical post-transplant period and was associated with distinct cellular and molecular signatures characterized by induction of regulatory T cells, reduced alloreactivity and balanced regulation of inflammatory signaling and innate immune responses. The TLR7-tolerant T cells preserved the immunological memory and generated in vitro virus-specific T cells upon antigen stimulation. The anti-aGVHD tolerization effect was direct and specific to TLR7 and required the receptor–ligand interaction; TLR7–/– T cells isolated from B6 TLR7–/– mice presented a distinct gene expression profile but failed to prevent aGVHD.Discussion
We propose an effective and clinically applicable ex vivo approach for aGVHD prevention through a transient and reversible immune reprogramming exerted by TLR7-tolerant donor lymphocytes. 相似文献149.
Ryotaro Yoshida Akihiro Matsuura Kuniko Einaga Yumiko Ushio Naoki Yamamoto Yukio Yoneda 《Microbiology and immunology》1997,41(2):149-159
It has been reported that the rejection of tumor allografts is mainly mediated by cytotoxic T lymphocytes (CTLs). Here, we characterized the cytotoxic effector cells of C57BL/6 (B6; H-2b) mice infiltrating into the rejection site of the i.p. allografted Meth A fibrosarcoma (or P815 mastocytoma) cells of H-2d origin. Two types of cytotoxic cells (i.e., CD8+ CTLs and macrophages (Mφs)) were identified by flow cytometric fractionation of the infiltrates or by specific in vitro elimination of cells either with antibody (Ab)-coated beads or with an Ab-plus complement. Of particular interest, these effector cells showed distinct and unique target specificities. First, the CTLs were inactive against transplanted tumor (e.g., Meth A) cells, whereas they were cytotoxic against donor-related concanavalin A (Con A) blasts as well as CTLL-2 (H-2b) cells transfected with a class I gene of H-2d origin. A cold target competition assay suggested that the CTLs were composed of multiple sets of T cells, each of which specifically recognized different allo-antigens. Second, the Mφs lysed the allografted tumor cells but were inert toward the Con A blasts and the CTLL-2 transfectants. Unexpectedly, the infiltration of Mφs preceded the infiltration of CTLs by several days during the course of rejection. These results indicate that two distinct populations of unique cytotoxic cells (i.e., CTLs and Mφs) are induced in the allografted tumor rejection site, and that the infiltration of cytotoxic Mφs responsible for rejection precedes that of the CTLs cytotoxic against cells expressing donor-related allo-antigens. 相似文献
150.
Omar Bagasra Bernice M. Eppright Ivan Damjanov 《Cancer immunology, immunotherapy : CII》1998,15(1):27-31
Summary A latex bead technique modified for measuring the plaque-forming cell (PFC) response to teratocarcinoma tumor antigens in syngeneic animals is described.With this method one can detect both the primary (IgM) and the secondary (IgG) immune response to tumor antigens. Optimal detection of the PFC response depends on the proper ratio of sheep red blood cells to latex beads and the dose of tumor cell antigen used for immunization. The presence of fetal calf serum interfered with immunization of animals and the coating of the latex beads with the tumor cell antigens. The plaques obtained in response to immunization with teratocarcinoma cell antigens varied in size, probably reflecting the complex immune response to more than one class of antigens on tumor cells. 相似文献