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41.
TNF-?? is an endogenous signaling protein which controls physiological activities and participates in immune response. It is known to interact with TNF receptors (TNFR), of which have two kinds leading to totally different effects. Binding of TNF-?? to TNFR1 can induce either cell proliferation or cell death, i.e., necroptosis, depending on the kinds of protein to which it binds during the signaling cascade. On the contrary, binding of TNF-?? to TNFR2 induces only cell death process. TNF-?? can also cause antiviral effect by inducing interferon, and can inhibit tumor growth. Moreover, TNF-?? helps action of immune cells and it leads to increasement of tumor cell lysis. TNF-?? also makes tumor vessels more permeable and induces coagulation and thrombosis in the tumor vessels, which ultimately contribute to antitumor effect. However, TNF-?? also has several toxic effects, which include the change in redox status of antioxidant factors, induction of excess inflammation response, and action as pro-inflammatory cytokine of itself. These toxicities need to be considered when developing TNF-?? as an anticancer agent. In this review, pharmaceutical approaches to optimize and utilize its antitumor activity of TNF-?? as well as to decrease its adverse effect are discussed.  相似文献   
42.
Abstract

To increase healing rate of tympanic membrane (TM) perforations, patching procedure has been commonly conducted. Biocompatible, biodegradable patching materials which is not limited across cultures is needed. The authors evaluated the effectiveness of novel transparent duck’s feet collagen film (DCF) patch in acute traumatic TM perforation. This procedure was compared with spontaneous healing and paper patching. Cell proliferation features were observed in paper and DCF patches. Forty-eight TMs of 24 rats were used for animal experiment, perforations were made on each TMs, and divided into three groups according to treatment modality. Sixteen were spontaneously healed, 16 were paper patched and 16 were DCF patched. The gross and histological healing results were analyzed. Both paper and DCF patch showed no cytotoxicity, but cell proliferations were more active in DCF than paper in early stage. In animal study, the healing of TM perforations were completed within 14 days in all three groups, but found to be faster in DCF patch group than paper patch or spontaneous healing group. The DCF patches were transparent and size of DCF patches were gradually decreased, so there were no need to remove the DCF patches to check the wound status or after the completion of healing. According to this result, authors concluded that DCF patch is transparent, biocompatible and biodegradable material, and can induce fast healing in acute traumatic TM perforations.  相似文献   
43.
Biopsying of children is often difficult to accomplish and traumatic. Consequently, techniques that avert biopsy are welcome in children. We describe the use of handheld dermoscopy for confirmation of the diagnosis of lesions with dermal thinning, including focal dermal hypoplasia, aplasia cutis, and striae. The major advantage of this technique is rapid diagnosis in the absence of a surgical procedure.  相似文献   
44.
Although momilactone B has been studied as an allelochemical of rice (Oryza sativa L.), to date we have no report showing the effect of momilactone B on mammalian cells. This study was undertaken to examine whether this allelochemical has anticancer activity on cancer cells. We show here that momilactone B at micromolar doses has antitumor efficacy by inducing apoptosis in several blood cancer cells including human leukemic T cells. In addition, our study elucidated that anticancer activity of momilactone B on human leukemic T cells resulted from the induction of apoptosis via caspase and mitochondria. From these results, momilactone B can be considered as a novel therapeutic strategy for human leukemic T cells from its direct apoptosis-inducing activity.  相似文献   
45.
Cells can resist and even recover from stress induced by acute hypoxia, whereas chronic hypoxia often leads to irreversible damage and eventually death. Although little is known about the response(s) to acute hypoxia in neuronal cells, alterations in ion channel activity could be preferential. This study aimed to elucidate which channel type is involved in the response to acute hypoxia in rat pheochromocytomal (PC12) cells as a neuronal cell model. Using perfusing solution saturated with 95% N2 and 5% CO2, induction of cell hypoxia was confirmed based on increased intracellular Ca2+ with diminished oxygen content in the perfusate. During acute hypoxia, one channel type with a conductance of about 30 pS (2.5 pA at -80 mV) was activated within the first 2~3 min following onset of hypoxia and was long-lived for more than 300 ms with high open probability (Po, up to 0.8). This channel was permeable to Na+ ions, but not to K+, Ca+, and Cl- ions, and was sensitively blocked by amiloride (200 nM). These characteristics and behaviors were quite similar to those of epithelial sodium channel (ENaC). RT-PCR and Western blot analyses confirmed that ENaC channel was endogenously expressed in PC12 cells. Taken together, a 30-pS ENaC-like channel was activated in response to acute hypoxia in PC12 cells. This is the first evidence of an acute hypoxia-activated Na+ channel that can contribute to depolarization of the cell.  相似文献   
46.
An understanding of the differences in clinical manifestations and laboratory abnormalities between subtypes of cutaneous lupus erythematosus (CLE) is still lacking. The purpose of this study was to analyze demographic, clinical and histological features of CLE according to three main presentation subsets: acute (ACLE), subacute (SCLE) and chronic (CCLE). A 10‐year retrospective analysis was performed on data from patients who were diagnosed with CLE between March 2005 and September 2015 in a Korean tertiary referral dermatology clinic. We compared demographic data and clinical and histological findings between three different CLE groups. An overall sample of 220 patients with CLE consisted of 67 patients with ACLE, 25 patients with SCLE and 135 patients with CCLE. Patients with CCLE regardless of systemic lupus erythematosus (SLE) presence had lower prevalence of anemia, urinary abnormalities and elevated erythrocyte sedimentation rate. Furthermore, CCLE patients who only had skin lesions showed lower female predominance, lower extracutaneous manifestation, fewer laboratory and immunological abnormalities including low antinuclear antibody titers and the lowest positivity for C3, C4 and anti‐dsDNA, anti‐Ro, anti‐Sm and anti‐RNP antibodies, and more prominent perieccrine inflammation and dermal fibrosis in histological findings. Considering distinct cutaneous manifestations of LE, a comprehensive awareness of each CLE subtype is important for achieving a favorable prognosis through appropriate diagnosis and management. This study provides comparative clinical and histological profiles of patients with different CLE subtypes in Korea.  相似文献   
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The chitosan-caffeic acid (CCA) conjugate shows a hepatoprotective effect against oxidative stress-induced hepatic damage in cultured hepatocytes. The objective of this study is the verification of the hepatoprotective effect of the CCA in vivo against ethanol-induced liver injury in mice. The administration of ethanol resulted in the increase of the serum-aminotransferase activities (AST and ALT), triglycerides, total cholesterol, and lipid peroxidation. The CCA co-administration, however, significantly (p < 0.05) ameliorated these serum biomarkers. The antioxidant-enzyme activities in the liver tissue, including those of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), were significantly decreased by a chronic ethanol administration, whereas the hepatic lipid-peroxidation level was increased. Moreover, the chronic ethanol administration elevated the gene expression of pro-inflammatory cytokines such as tumor-necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the liver tissue. The CCA co-administration, however, significantly (p < 0.05) increased the activities of the SOD, CAT, and GPx and caused the down-regulation of the TNF-α- and IL-6-gene expressions in the liver tissue. An histopathologic evaluation also supported the hepatoprotective effect of the CCA against ethanol-induced hepatotoxicity in the mice.  相似文献   
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