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991.

OBJECTIVE

To assess the pathological features of Gleason score 6 prostate cancers after radical prostatectomy in the low (<4 ng/mL) and intermediate range of prostate‐specific antigen level (4–10 ng/mL), as such prostate cancers are considered to be well differentiated tumours with a low risk for recurrence after therapy.

PATIENTS AND METHODS

In all, 1354 patients with T1c prostate cancer and PSA levels of <10.0 ng/mL had a radical retropubic prostatectomy. Patients with Gleason score 6 tumours were divided into two groups, those with PSA levels of <4 and 4.0–10.0 ng/mL. Extracapsular extension, positive surgical margins, biochemical recurrence (BCR) and mean time to BCR were evaluated.

RESULTS

Of the 1354 patients, there were 437 (32.3%) with Gleason score 6 prostate cancers. Patients in the low PSA group had less extraprostatic disease than those with a higher level (5.9% vs 14.5%) and both groups had an almost equal proportion of positive surgical margins (9.4% vs 11.0%). In the low PSA group there was statistically significantly shorter BCR than in the high PSA group, with a mean time to BCR of 1.7 vs 3.1 years.

CONCLUSIONS

These results show a statistically significantly higher rate of extraprostatic disease and earlier BCR in men with a high than a low PSA level even in Gleason score 6 prostate cancer. As the rate of BCR and extracapsular extension are significantly related to prostate cancer mortality, these findings further support the concept of screening using low PSA levels.  相似文献   
992.
The aim of this study was to determine platelet activity and reactivity and the effects of unfractionated heparin (UFH) and enoxaparin on platelet function during carotid eversion endarterectomy under local anesthesia. Twenty symptomatic patients undergoing carotid endarterectomy were randomly assigned to either 5,000 units of UFH or body weight-adjusted enoxaparin (0.5 mg/kg body weight) as an intraoperative intravenous bolus. The activity of platelets was assessed by measuring the expression of CD62p and CD41 with flow cytometry. Additionally, platelet-leukocyte aggregates (PLAs) were enumerated. The reactivity of platelets was evaluated by measuring the expression of the same antigens after stimulation. In addition, platelet reactivity was also analyzed using a PFA-100 analyzer. A significant increase in platelet activity was observed during surgery for CD41 and CD62p (p = .002 and < .001, respectively). The number of PLAs showed no significant changes during surgery. Yet there was a significant difference between patients treated with UFH and patients treated with enoxaparin. No difference for platelet activity or reactivity for patients receiving either UFH or enoxaparin prior to cross-clamping of the carotid arteries was seen. The formation of PLAs after endarterectomy was significantly higher in the UFH group; thus, PLAs are probably a useful surrogate parameter for measuring platelet activity.  相似文献   
993.
994.
Schizophrenia is associated with neuroanatomical abnormalities. Gray matter decrease seems to predate first schizophrenic episode. Whether white matter abnormalities predate the onset of psychotic symptoms is unclear. We investigated this issue using voxel-based morphometry (VBM) of structural magnetic resonance images to examine individuals with prodromal symptoms who were at ultra high-risk (UHR) of developing schizophrenia and compared them to first-episode schizophrenic patients and healthy controls. White matter volume maps from high-resolution magnetic resonance T1 weighted whole brain images were analyzed in a cross-sectional study using SPM2 in 30 UHR patients, 23 first-episode schizophrenic patients and 29 healthy controls. UHR patients showed significant lower white matter volume in the right superior temporal lobe compared to healthy controls. First-episode patients with schizophrenia showed widespread smaller white matter volume bilaterally compared to UHR patients. This study provides first evidence for smaller white matter volume in the right temporal lobe of UHR patients, one of the key structures in the pathophysiology of schizophrenia. Furthermore, white matter abnormalities seem to progress after transition into schizophrenia.  相似文献   
995.
To assess the risk of acquiring a West Nile virus (WNV) infection in Germany, we investigated samples from migrating and from resident birds. Because of their stay in or migration through WNV-endemic regions, these birds are at risk to become infected with WNV. Blood samples from 3,399 birds, representing 87 bird species, were collected in Germany in 2000 and in 2002-2005. Overall, 53 birds belonging to 5 species had WNV-neutralizing antibodies. Fifty-nine birds belonging to 9 species were reactive by WNV immunofluorescence assay, and 8 birds had neutralizing antibodies against Usutu virus. Because of maternal antibody transfer via egg yolk, WNV-antibody titers in white stork nestlings were generally lower than those in adults. Despite a relatively high percentage of stork nestlings with antibodies, no viral genomes were detectable by polymerase chain reaction. In Germany, the prevalence of antibodies to WNV in migrating birds wintering in Africa or southern Europe is comparatively low.  相似文献   
996.
OBJECTIVE: Insufficient angiogenesis with tissue ischemia and accumulation of extracellular matrix are hallmarks of systemic sclerosis (SSc). Based on the severely decreased oxygen levels in the skin of patients with SSc, we aimed to investigate the role of hypoxia in the pathogenesis of SSc. METHODS: Subtractive hybridization was used to compare gene expression in dermal fibroblasts under hypoxic and normoxic conditions. Dermal fibroblasts were further characterized by exposure to different concentrations of oxygen and for different time periods as well as by interference with hypoxia-inducible factor 1alpha (HIF-1alpha). The systemic normobaric hypoxia model in mice was used for in vivo analyses. RESULTS: Several extracellular matrix proteins and genes involved in extracellular matrix turnover, such as thrombospondin 1, proalpha2(I) collagen, fibronectin 1, insulin-like growth factor binding protein 3, and transforming growth factor beta-induced protein, were induced by hypoxia in SSc and healthy dermal fibroblasts. The induction of these genes was time- and dose-dependent. Experiments with HIF-1alpha-knockout mouse embryonic fibroblasts, deferoxamine/cobalt ions as chemical stabilizers of HIF-1alpha, and HIF-1alpha small interfering RNA consistently showed that extracellular matrix genes are induced in dermal fibroblasts by HIF-1alpha-dependent, as well as HIF-1alpha-independent, mechanisms. Using the systemic normobaric hypoxia mouse model, we demonstrated that dermal hypoxia leads to the induction of the identified extracellular matrix genes in vivo after both short exposure and prolonged exposure to hypoxia. CONCLUSION: These data show that hypoxia contributes directly to the progression of fibrosis in patients with SSc by increasing the release of major extracellular matrix proteins. Targeting of hypoxia pathways might therefore be of therapeutic value in patients with SSc.  相似文献   
997.
OBJECTIVE: To investigate the pathologic nature of features termed "bone erosion" and "bone marrow edema" (also called "osteitis) on magnetic resonance imaging (MRI) scans of joints affected by rheumatoid arthritis (RA). METHODS: RA patients scheduled for joint replacement surgery (metacarpophalangeal or proximal interphalangeal joints) underwent MRI on the day before surgery. The presence and localization of bone erosions and bone marrow edema as evidenced by MRI (MRI bone erosions and MRI bone marrow edema) were documented in each joint (n=12 joints). After surgery, sequential sections from throughout the whole joint were analyzed histologically for bone marrow changes, and these results were correlated with the MRI findings. RESULTS: MRI bone erosion was recorded based on bone marrow inflammation adjacent to a site of cortical bone penetration. Inflammation was recorded based on either invading synovial tissue (pannus), formation of lymphocytic aggregates, or increased vascularity. Fat-rich bone marrow was replaced by inflammatory tissue, increasing water content, which appears as bright signal enhancement on STIR MRI sequences. MRI bone marrow edema was recorded based on the finding of inflammatory infiltrates, which were less dense than those of MRI bone erosions and localized more centrally in the joint. These lesions were either isolated or found in contact with MRI bone erosions. CONCLUSION: MRI bone erosions and MRI bone marrow edema are due to the formation of inflammatory infiltrates in the bone marrow of patients with RA. This emphasizes the value of MRI in sensitively detecting inflammatory tissue in the bone marrow and demonstrates that the inflammatory process extends to the bone marrow cavity, which is an additional target structure for antiinflammatory therapy.  相似文献   
998.
OBJECTIVE: To determine the nature of the initial changes of joint inflammation occurring before, at the time of, and shortly after onset of clinically apparent arthritis. METHODS: Human tumor necrosis factor (TNF)-transgenic mice were assessed for clinical, histologic, immunophenotypic, serologic, and molecular changes at the preclinical phase of arthritis, at the onset of disease, and at the stage of early clinical disease. In addition, the effects of a genetic osteoclast deficiency and pharmacologic inhibition of TNF were studied in these initial phases of disease. RESULTS: Initial articular changes were observed even before the start of clinical symptoms. Infiltration of the tendon sheaths by granulocytes and macrophages as well as formation of osteoclasts next to the inflamed tendon sheaths were the first pathologic events. Tenosynovitis rapidly led to remodeling of the sheaths into pannus-like tissue, which formed osteoclasts that invaded the adjacent mineralized cartilage. Early lesions were associated with up-regulation of interleukin-1 (IL-1) and IL-6 as well as activation of p38 MAPK and ERK. In contrast, absence of osteoclasts led to uncoupling of tenosynovitis from invasion into cartilage and bone. TNF blockade also attenuated the pathologic changes associated with tenosynovitis. CONCLUSION: Structural damage begins even before the onset of clinical symptoms of arthritis and involves the tendon sheaths as well as adjacent cartilage and bone. These results suggest that tenosynovitis is an initiating feature of arthritis and that joint destruction starts right from the onset of disease. Our findings thus underscore the importance of immediate initiation of an effective therapy in patients with rheumatoid arthritis.  相似文献   
999.
Age-related thymopoietic insufficiency has been proposed to be related to either defects in lymphohematopoietic progenitors or the thymic microenvironment. In this study, we examined whether keratinocyte growth factor (KGF), an epithelial cell-specific growth factor, could increase thymopoietic capacity in aged mice by restoration of the function of thymic epithelial cells (TECs). The thymic cellularity in KGF-treated aged mice increased about 4-fold compared to placebo-treated mice, resulting in an equivalent thymic cellularity to young mice. Enhanced thymopoiesis was maintained for about 2 months after a single course of KGF, and sustained improvement was achieved by administration of monthly courses of KGF. With the enhanced thymopoiesis after KGF treatment, the number of naive CD4 T cells in the periphery and T-cell-dependent antibody production improved in aged mice. KGF induced increased numbers of TECs and intrathymic interleukin-7 (IL-7) production and reorganization of cortical and medullary architecture. Furthermore, KGF enhanced thymopoiesis and normalized TEC organization in klotho (kl/kl) mice, a model of premature degeneration and aging, which displays thymopoietic defects. The result suggests that TEC damage is pathophysiologically important in thymic aging, and KGF therapy may be clinically useful in improving thymopoiesis and immune function in the elderly.  相似文献   
1000.
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