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71.
The hypophysis of the brook trout is irrigated by blood vessels which originate from the internal carotid arteries. These are: (1) branches of the ventral hypothalamic arteries that give rise to an extensive capillary plexus in the neurohypophysis from which vessels extend into all regions of the adenohypophysis; (2) branches of the caudal hypothalamic artery that irrigate the saccus vasculosus and continue anteriorly to supply the ventral areas of the meta-adenohypophysis; (3) a caudal hypophyseal artery which vascularizes a portion of the meta-adenohypophysis however, this vessel is not always present; (4) a pair of small arteries which supply the peripheral regions of the gland directly from the carotids. Most of the neurosecretory fibers of the preoptic-hypophyseal tract terminate close to capillaries in the neurohypophysis. A few axons extend into meso-adenohypophyseal tissue. It is suggested that the secretory activities of the pro-, meso- and metaadenohypophyses are governed by hypothalamic factors that are chiefly transmitted to the gland cells via the vascular system (indirect control). However, the activity of the meso-adenohypophysis may also be regulated by factors which are transmitted directly to the cells from the endings of neurosecretory fibers which have traversed the neurohypophysis (direct control). The distribution and abundance of neurosecretion in the ventral hypophysis suggest the possibility of storage of hypothalamic products within this region.  相似文献   
72.
Defects in the gene that encodes SHP-1 protein tyrosine phosphatase result in multiple hematopoietic abnormalities and generalized autoimmunity in viable motheaten (me(v)) mice. These mice also exhibit early thymic involution and abnormalities in T cell development. Here, we describe the use of fetal thymic organ culture (FTOC) and bone marrow adoptive transfer to study the effects of SHP-1 deficiency on thymocyte development. Chimeric FTOC established with normal bone marrow placed onto deoxyguanosine-treated fetal thymic lobes or onto scid fetal thymic lobes generated T cells. Bone marrow from SHP-1-deficient me(v)/ me(v) mice generated decreased numbers of T cells in chimeric FTOC established using deoxyguanosine-treated thymi but generated normal numbers in chimeric FTOC established using scid thymi. However, scid fetal thymi seeded with me(v)/ me(v) bone marrow also exhibited morphological abnormalities and contained elevated numbers of macrophages. Addition of IL-7 to me(v)/ me(v) bone marrow-seeded scid FTOC led to increased cell numbers, particularly of macrophages. Intrathymic injection of IL-7 partially restored the ability of progenitor cells in me(v)/ me(v) bone marrow to populate the thymus of adoptive recipients. We conclude that abnormal T cell development in me(v)/ me(v) mice may in part be due to defects in the ability of bone marrow-derived accessory cells to provide bioavailable IL-7 to developing thymocytes.  相似文献   
73.
Infections are a common complication of allogeneic bone marrow transplantation and the leading cause of transplantation-related mortality. It had been hypothesized that transplantation following nonmyeloablative preparative regimens would result in fewer infections by causing less mucosal injury, less graft-versus-host disease, and allowing earlier immune reconstitution. We have retrospectively reviewed the infectious complications of 65 consecutive patients with advanced hematologic malignancies who underwent bone marrow transplantation using a novel preparative regimen consisting of cyclophosphamide, thymic irradiation, and in vivo T-cell depletion. Cytomegalovirus (CMV) infection occurred in 52% of cases in which the donor or recipient had evidence of prior CMV exposure. Using a strategy of preemptive therapy and secondary prophylaxis with ganciclovir, no CMV disease occurred. Infections with gram-positive bacteria predominated over the first 100 days after bone marrow transplantation. Thereafter, the relative proportion of gram-negative infections increased without a significant increase in episodes of neutropenia. The rate of bacterial infections was not influenced by relapse of the underlying malignancy. Seven patients developed infections with Aspergillus species, which was the most common infectious cause of death in these patients. Infections with viruses other than CMV (n=10) and with protozoan organisms (n=2) also occurred. The use of HLA-mismatched donors, the occurrence of grade II-IV acute graft-versus-host disease, and treatment with corticosteroids did not influence the risk of CMV or bacterial or fungal infections in patients who underwent transplantation following this preparative regimen. Overall, the incidence and spectrum of infections in this series was similar to the reported incidence of infections following conventional myeloablative allogeneic stem cell transplantation. We conclude that a quantitative T-cell deficiency in these extensively T-cell depleted patients may be a risk factor for infection, even in the absence of graft-versus-host disease.  相似文献   
74.
75.
Susceptible strains of mice that are naturally or experimentally infected with murine intestinal helicobacter species develop hepatic inflammatory lesions that have previously been described as chronic active hepatitis. The inflammatory infiltrates in some models of chronic autoimmunity or inflammation resemble tertiary lymphoid organs hypothesized to arise by a process termed lymphoid organ neogenesis. To determine whether hepatic inflammation caused by infection with helicobacter could give rise to tertiary lymphoid organs, we used fluorescence-activated cell sorting, immunohistochemistry, and in situ hybridization techniques to identify specific components characteristic of lymphoid organs in liver tissue sections and liver cell suspensions from helicobacter-infected mice. Small venules (high endothelial venules [HEVs]) in inflammatory lesions in Helicobacter species-infected livers were positive for peripheral node addressin. Mucosal addressin cell adhesion molecule also stained HEVs and cells with a staining pattern consistent with scattered stromal cells. The chemokines SLC (CCL 21) and BLC (CXCL13) were present, as were B220-positive B cells and T cells. The latter included a na?ve (CD45lo-CD62Lhi) population. These findings suggest that helicobacter-induced chronic active hepatitis arises through the process of lymphoid organ neogenesis.  相似文献   
76.
77.
This study chronicles an at-risk mother's experience in an alternative foster care program. Influenced by attachment theory, the Children's Ark reunited children with their mothers in a supervised home environment while also providing residential support, intensive therapy, and education. After losing custody of her infant Kindra, 18-year-old Anna participated in the Ark for 2 years, after which she regained custody of Kindra. We assessed Anna and Kindra at multiple times using a variety of instruments, including a semi-structured interview, the Adult Attachment Interview, and the Strange Situation procedure. Anna moved from a profoundly insecure state of mind to a secure one, while Kindra moved from a resistant to a secure attachment. Qualitative analyses of Anna's interviews documented growth in her capacity to use the important relationships at the Ark as secure bases and to welcome rather than fear intimacy with Kindra. The qualitative analyses also described growth in Anna's capacities for reflective functioning and positive changes in her internal working model. We conclude with an analysis of the process of change from the perspective of attachment theory.  相似文献   
78.
BACKGROUND: There is a continued need to develop more effective cancer immunotherapy strategies. Exosomes, cell-derived lipid vesicles that express high levels of a narrow spectrum of cell proteins represent a novel platform for delivering high levels of antigen in conjunction with costimulatory molecules. We performed this study to test the safety, feasibility and efficacy of autologous dendritic cell (DC)-derived exosomes (DEX) loaded with the MAGE tumor antigens in patients with non-small cell lung cancer (NSCLC). METHODS: This Phase I study enrolled HLA A2+ patients with pre-treated Stage IIIb (N = 4) and IV (N = 9) NSCLC with tumor expression of MAGE-A3 or A4. Patients underwent leukapheresis to generate DC from which DEX were produced and loaded with MAGE-A3, -A4, -A10, and MAGE-3DPO4 peptides. Patients received 4 doses of DEX at weekly intervals. RESULTS: Thirteen patients were enrolled and 9 completed therapy. Three formulations of DEX were evaluated; all were well tolerated with only grade 1-2 adverse events related to the use of DEX (injection site reactions (N = 8), flu like illness (N = 1), and peripheral arm pain (N = 1)). The time from the first dose of DEX until disease progression was 30 to 429+ days. Three patients had disease progression before the first DEX dose. Survival of patients after the first DEX dose was 52-665+ days. DTH reactivity against MAGE peptides was detected in 3/9 patients. Immune responses were detected in patients as follows: MAGE-specific T cell responses in 1/3, increased NK lytic activity in 2/4. CONCLUSION: Production of the DEX vaccine was feasible and DEX therapy was well tolerated in patients with advanced NSCLC. Some patients experienced long term stability of disease and activation of immune effectors.  相似文献   
79.
Multivalent MHC class II molecules containing peptide antigens are useful tools for the detection of antigen specific human CD4+ T cells. Tetramers produced by exogenous peptide loading onto empty class II molecules are comparable to tetramers with peptide tethered to the class II chain covalently, but have many practical advantages. Conditions for optimal peptide loading to generate tetramers are discussed and optimal conditions of using tetramers for staining T cells are examined. As the frequency of antigen specific CD4+ T cells in peripheral blood is low, we demonstrate that an in vitro expansion step is effective in detecting low frequency T cells. Two new applications with tetramers, their uses for mapping T cell epitopes and for the detection of low affinity T cells are described. In a clinical setting, potential applications include using these reagents for monitoring disease progression during clinical intervention.  相似文献   
80.
Alagille syndrome is an autosomal dominant disorder affecting multiple organ systems, predominantly the liver, heart, skeleton, eye, face, and kidney. The phenotype in Alagille syndrome is highly variable both within and between families. We report monozygotic twins with Alagille syndrome concordant for a mutation in Jagged1 but discordant for clinical phenotype. The twins' monozygosity was confirmed by molecular testing. A de novo splice site mutation was identified in exon 6 (1329 + 2T --> G) in both children. Both twins display a severe form of Alagille syndrome; however, one twin has a severe pulmonary atresia with mild liver involvement, while the other has tetralogy of Fallot and severe hepatic involvement, which has required liver transplantation. Potential mechanisms for phenotypic variability among monozygotic twins are discussed. This is the first reported case of discordance in phenotype in monozygotic twins with Alagille syndrome. This case implies that genotypic variations alone do not explain the clinical variability seen in Alagille syndrome and supports the contributory role of nongenetic factors in phenotype determination.  相似文献   
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