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81.
An autopsy case of systemic histiocytosis with excessive deposition of K-type light chain crystals was reported in a 58 year-old man who had consistently showed K-type light chain paraproteinemia, Bence Jones proteinuria and hypogammaglobulinemia for about 10 years until his death. However, no bony destruction was found by repeated X-ray examinations. At autopsy, extensive hyperplasia of crystal-storing histiocytes was observed in the bone marrow, spleen, liver, lymph nodes, interstitial tissues of visceral organs and loose connective tissues. In the bone marrow and some other tissues, mild proliferation of plasmocytoid cells containing small crystals were found, Histochemically the crystals positively stained with various methods for amino acids and proteins, especially with Weigerts'method for fibrin Ultra-structurally intralysosomal crystal deposition was confirmed in the storage histiocytes and derivation of the crystals from Golgi's sacculi in the plasmocytoid cells was suggested. Biochemically the crystals were regarded as mainly consisting of dimers of a variable half of light chain immunoglobulin and immunochemically and immunohistochemically reacted to anti- type light chain serum. Such a generalized storage histiocytosis may be secondarily induced by immunoglobulin synthesized in plasmocytoid cells.  相似文献   
82.
2,4,6-Triphenyl-3,4-dihydro-s-tetrazin-1(2H)-yl ( 1 ) (1,3,5-triphenylverdazyl) was allowed to react with ethyl- and butyllithium, ethyl-, isopropyl-, and butylmagnesium bromide, as well as benzylmagnesium chloride to give the coupling products 2a–d . These results indicate that structures corresponding to 2 are present in the polymers resulting from vinyl monomers containing the verdazyl structure, if they are initiated with alkyllithium or a Grignard reagent. A reaction mechanism is discussed.  相似文献   
83.
The current knowledge of the distribution of the mouse mammary tumor virus (MMTV) proviral genomes and the mechanism of mammary tumorigenesis by MMTV in mice, with the main emphasis on Asian feral mice, is reviewed. The relevant earlier discoveries on the mode of MMTV transmission are summarized to provide an outline of the biology of MMTV. Finally, the viral etiology of human breast cancer will be discussed.  相似文献   
84.
CED-9 prevents apoptosis in embryonic cells of Caenorhabditis elegans but not in mammalian cells. We show here that the prevention of apoptosis in mammalian cells requires a CED-3-cleaved form (68-280) of CED-9 which is localized in the inner mitochondrial membrane. The viability of PC12 and HeLa cells was significantly increased after death stimuli when truncated CED-9 was expressed in these cells but full-length CED-9 did not. The truncated CED-9 expressed in these cells was largely localized to the inner mitochondrial and the endoplasmic reticulum membranes, while full-length CED-9 was detected mainly in endoplasmic reticulum fractions. Moreover, truncated CED-9 in purified mitochondria was resistant to trypsin digestion, but full-length CED-9 was not. These results suggest that the CED-3-cleaved form of CED-9 prevents apoptosis in mammalian cells by localizing to the inner mitochondrial membrane.  相似文献   
85.
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor.  相似文献   
86.
87.
Our previous study showed that the saliency of a target increases the gain of smooth pursuit initiation. In this study, we examined the interocular transfer of this effect in five humans. A square red frame surrounding the target was used as a cue to indicate the initial target position. In the cue condition, the responses were similar, irrespective of the eye to which the cue was presented, and were significantly larger than in the no-cue condition. The result suggests that central pathways that receive input from both eyes mediate the effect of saliency on smooth pursuit initiation.  相似文献   
88.
This study was carried out to determine the role of nitric oxide (NO) in Staphylococcus aureus infection in mice. NO production in spleen cell cultures was induced by heat-killed S. aureus. Expression of mRNA of the inducible isoform of NO synthase (iNOS) was induced in the spleens and kidneys of S. aureus-infected mice. When mice were treated with monoclonal antibodies (MAbs) against tumor necrosis factor alpha (TNF-α) or gamma interferon (IFN-γ) before S. aureus infection, the induction of iNOS mRNA expression in the kidneys was inhibited. These MAbs also inhibited NO production in spleen cell cultures stimulated with heat-killed S. aureus. NO production in the spleen cell cultures and levels of urinary nitrate plus nitrite were suppressed by treatment with aminoguanidine (AG), a selective inhibitor of iNOS. The survival rates of AG-treated mice were significantly decreased by either lethal or sublethal S. aureus infections. However, an effect of AG administration on bacterial growth was not observed in the spleens and kidneys of mice during either type of infection. Production of TNF-α and IFN-γ was not affected by AG treatment in vitro and in vivo. These results suggest that NO plays an important role in protection from lethality by the infection, but the protective role of NO in host resistance against S. aureus infection was not proved. Moreover, our results show that TNF-α and IFN-γ regulate NO production while NO may not be involved in the regulation of the production of these cytokines during S. aureus infection.  相似文献   
89.
Conserved tRNA gene cluster in starfish mitochondrial DNA   总被引:10,自引:0,他引:10  
Summary Partial sequencing of mtDNA from four long-diverged species of starfish reveals the existence of a conserved cluster of 13 tRNA genes, organized in a manner similar to that of the tRNA cluster of sea urchin mtDNA, but located at a position distant from the presumed replication origin. These findings suggest that a clustered organization of tRNA genes may have been present in the ancestral mitochondrial genome, and raise the possibility that tRNAs may have catalyzed the dispersal rather than the accumulation of the genes which encode them.  相似文献   
90.
Activated T cells responding to murine minor histocompatibility antigens (HA) were characterized according to the patterns of lymphokine activity production. Although B10.D2/nSN and BALB/c are mutually non-reactive in mixed lymphocyte reaction (MLR), graft-versus-host reaction (GVHR) can be induced by the injection of a large amount of B10.D2/nSN lymphoid cells into irradiated BALB/c recipient mice. Spleen cells from such GVHR mice spontaneously produced interleukin 3 (IL-3)-dependent cell-stimulating activity in cultures, but did not produce interleukin 2 (IL-2). Normal B10.D2/nSN spleen cells also produced IL-3-like activity, but not IL-2 in MLR supernatants, in response to irradiated BALB/c splenocytes. In addition, B-cell stimulatory factor-1 (BSF-1)/interleukin 4 (IL-4) and colony-stimulating factor (CSF) activity were detected in MLR supernatants. The properties of the produced lymphokine activities were similar to those produced in syngeneic transplant mice and syngeneic MLR, but a difference in the time course of lymphokine production existed between GVHR and syngeneic transplant mice. These results indicate that T cells may be activated in vivo in allogeneic transplantation when the donor and the recipient are matched for major HA, and are non-reactive in MLR. Also, the character of lymphokine-producing T cells activated by minor HA may not be qualitatively different from those responding to irradiated syngeneic cells.  相似文献   
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