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51.
Cross-linking of Fas and Fas ligand (FasL) induces apoptosis in Fas-bearing cells and regulates apoptosis. Fas is widely expressed in normal human tissues, but FasL expression has been considered to be restricted to lymphoid tissues. Recent studies have demonstrated that FasL is also expressed in some nonlymphoid tissues. To screen the in situ expression of FasL in normal human tissues, immunohistochemistry was performed using paraffin-embedded human tissues. FasL immunostaining was easily detected in testis, neurons, trophoblasts, tonsil, lymph node, Paneth cells, hepatocytes, renal tubular epithelium and bronchial epithelium, consistent with previous reports. Surprisingly, FasL was also expressed in many other cell types, including thymic medulla, skeletal muscle, cardiac muscle, pituitary gland, parathyroid gland, prostate glands, oocytes, epithelium of fallopian tube, endometrial glands, and gastric parietal cells. These findings demonstrate that FasL is widely expressed in human tissues and suggest that wide but cell-type specific expression of FasL may not only be implicated in the regulation of immune homeostasis but also in the regulation of cell death and life in many cell types in vivo.  相似文献   
52.
Transfer of extensor carpi radialis longus or brevis for opponensplasty   总被引:4,自引:0,他引:4  
For the restoration of thumb opposition many types of tendon transfer techniques have been described. The flexor digitorum superficialis (FDS) of the ring finger is commonly selected as a motor. On occasion, however, the quality of the flexor muscles of the fingers or wrist is not good enough for tendon transfer and another available muscle must be selected. In this situation, we have preferred to use an extensor carpi radialis longus (ECRL) or brevis (ECRB) transfer to restore opposition of the thumb. Follow-up examination, at an average 5 years and 10 months after operation, showed that the results of ten of 11 transfers were excellent and the other was good.  相似文献   
53.
Wang JC  Yoo S  Delamarter RB 《Spine》1999,24(5):425-427
STUDY DESIGN: A review of all the presentations at three major spine specialty meetings held over a 3-year period. OBJECTIVES: To determine the rate of publication in peer-reviewed journals after presentations at major spine meetings conducted annually by the following three organizations: North American Spine Society (NASS), Scoliosis Research Society (SRS), and International Society for the Study of the Lumbar Spine (ISSLS). SUMMARY OF BACKGROUND DATA: The rate of publication for presentations at national and international meetings has been determined for medical and surgical subspecialties. This rate has been used to judge the quality of the content of the meetings and to determine the validity of the research presentations. METHODS: All presentations either in poster or oral presentation form were entered into a database covering a 3-year period for spine specialty meetings conducted annually by the following three organizations: NASS 1990 to 1992, SRS 1991 to 1993, and ISSLS 1991 to 1993. A computer search for each abstract was performed with the Melvyl Medline Plus database to determine if the abstract had been published in a peer-reviewed journal from 1990 to the end of 1997. Publication rates for presentations at these three meetings were determined over a 3-year period. RESULTS: A total of 1186 abstracts were listed over a 3-year period in the final programs of these three meetings for the years 1991 to 1993 (SRS, ISSLS) and 1990 to 1992 (NASS). Of these 1186 abstracts, 516 were published in peer-reviewed journals, giving an overall publication rate of 43.5%. The publication rates for the three different meetings (NASS, SRS, ISSLS) were similar, with values of 40%, 47%, and 45% respectively. More than 90% of the publications resulting from these meetings were published within a period of 4 years from the data of the meeting. CONCLUSIONS: The publication rates of presentations at three major spine specialty meetings are high and quite comparable with the publication rates of meetings in other medical subspecialties. This reflects the high quality of the meeting programs and validates their selection process.  相似文献   
54.
Previous studies have suggested that hepatic arterial flow in heterotopic partial liver transplants is necessary to ensure graft survival and regenerative capacity. This report presents findings in a syngeneic rat strain (Lewis) that partial liver transplants can be successfully heterotopically transplanted in the long term with the only inflow coming from the portal vein. When the host liver undergoes a nearly complete resection at 3-4 weeks, the transplanted liver regenerates to maintain the health of the host. Moderate to massive hepatocellular necrosis occurs in the first 3 months postoperatively, with recovery by 4-5 months. Liver transplants 8-10 months postoperatively appear architecturally normal. No host liver tissues were found to be regenerating after subtotal host liver resection. We conclude that portal vein reconstruction without hepatic arterial inflow can sustain a partial liver transplant in the long term, replacing the function of the host liver.  相似文献   
55.
This periodic report includes intermittent results of consecutive pancreaticoduodenal (Pd) and kidney (Kt) transplants in inbred rats and results on double kidney transplants that did not follow sequential transplant protocol. Eight 24-month-old Lewis pancreas, kidney, and aorta served histological controls showing normal histological architecture with no atherosclerosis developed in the aorta. Thirty-four month old pancreas and thirty-two month old kidneys, which resided in young hosts for at least three occasions, appeared as youthful Pd and Kt grafts. They show normal histological appearance for more than the expected life span of a Lewis rat. The fact that not only pancreases but also kidneys outlived their host leads to the study of other different organs' viability as aged valuable grafts. Nevertheless, the threats by the development of atherosclerosis in graft-associated aortas resulted in slow progression of the follow-ups.  相似文献   
56.
Laser in situ keratomileusis for the treatment of myopia   总被引:3,自引:0,他引:3  
  相似文献   
57.
Bioassay-guided fractionation of an H2O extract of the barks of Fraxinus rhynchophylla has furnished two inducible nitric oxide synthase (iNOS) inhibitory compounds, ferulaldehyde (1) and scopoletin (3) together with a coumarin, fraxidin (2). Compounds 1 and 3 showed inhibition of nitric oxide (NO) synthesis in a dose-dependent manner by murine macrophage-like RAW 264.7 cells stimulated with interferon-gamma (IFN-gamma) plus lipopolysaccharide (LPS). The inhibition of NO synthesis of 1 was reflected in the decreased amount of iNOS protein, as determined by Western blotting.  相似文献   
58.
Lee SJ  Yun YS  Lee IK  Ryoo IJ  Yun BS  Yoo ID 《Planta medica》1999,65(7):658-660
A new lignan named as hibiscuside, (+)-pinoresinol 4-O-[beta-glucopyranosyl (1--->2)-alpha-rhamnoside] (1), and a known lignan, syringaresinol (2) were isolated from the root bark of Hibiscus syriacus together with two feruloyltyramines (3,4) and three known isoflavonoids (5,6,7). The structures of these compounds have been established on the basis of their NMR, mass UV spectra. Among these phenolic compounds, 6"-O-acetyldaidzin (5), 6"-O-acetylgenistin (6), and 3-hydroxydaidzein (7) with IC(50) values of 8.2, 10.6, and 4.1 microM, respectively, significantly inhibited lipid peroxidation in rat liver microsomes. Hibiscuside (1), E- and Z-N-feruloyl tyramines (3,4) exhibited moderate antioxidant activity.  相似文献   
59.
Aiming at the development of anticancer agents by modification of phenolic benzo[c]phenanthridine alkaloid, additional hydroxyl group was put on C10 position of fagaridine (1) by a biomimetic synthetic procedure to afford 10-hydroxyfagaridine (12). All of the synthetic intermediates were also screenedin vitro antitumor activities against five different cell lines as well as12. Among them the representative cytotoxic results are shown as follows;p-quinone (11) [ED50 (A549=0.22 μg/ml), (HCT15=0.21 μg/ml), fagaridine (1) (HCT 15=0.41 μg/ml), olefin (6) (HCT 15=0.06 μg/ml), acetal (7) (SKMEL-2=0.07 μg/ml), dihydrofagaridne (10) (A549=0. 38 μg/ml), 10-hydroxyfagaridine (12) (A 549=0.45 μg/ml). From these observation three main remarks can be drawn; (i) the iminium part of benzo[c]phenanthridine is not essential for showing acitvities, (ii) the additional hydroxyl group did not contribute to enhance the cytotoxicity, (iii) the 3-arylisoquinolin-1(2H)-one derivatives were found to display significantin vitro antitumor activity.  相似文献   
60.
PURPOSE: We have proposed to characterize the mechanism through which bioactive surgical sutures generate a T(H)1 immune response and to define the immune-stimulating half-life of the sutures. EXPERIMENTAL DESIGN: Bioactive sutures of interferon gamma (IFNgamma), interleukin 2 (IL-2), anti-CD3/CD28, anti-CD3/CD28 + IL-2, or anti-CD3/CD28 + IFNgamma sutures were used to stimulate lymphocytes from normal donors and from head and neck cancer patients in vitro over a 24-day period. Cell supernatants were analyzed by ELISA, and T cells were phenotyped to characterize the immune response generated. Intracellular cytokine staining was performed to measure the expansion of flu-specific T cells. Electromobility shift assay and supershift assay were used to measure the intranuclear DNA binding activity of nuclear factor kappaB and its p65 subunit in T cells activated by sutures in the presence and absence of a proteasome inhibitor, MG-132. RESULTS: Anti-CD3/CD28, anti-CD3/CD28 + IL-2, or anti-CD3/CD28 + IFNgamma generated a prolonged T(H)1 immune response for 18 days in vitro. Anti-CD3/CD28 expanded flu-specific T cells. Activated T cells demonstrated enhanced CD40 ligand (CD40L) expression within 72 hours of stimulation, which stimulated other cells to secrete IL-12. Stimulated T cells demonstrated increased intranuclear expression of nuclear factor-kappaB, which was blocked by MG-132, and also reduced CD40L and IL-12 expression. CONCLUSIONS: This is the first report to demonstrate that bioactive surgical sutures can generate a prolonged T(H)1 immune response and expand flu-specific T cells. Bioactive sutures, which are primarily a T-cell stimulant, also stimulated other cells to secrete IL-12 and prolonged the immune response. Sutures may provide a novel in situ stimulating strategy for enhancing the immune system of cancer patients.  相似文献   
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