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81.
AIM: To evaluate whether serum levels of nitric oxide (NO^.) and plasma levels of cyclic guanosine monophosphate (cGMP) and total glutathione (GSH) are altered in patients with alcoholic cirrhosis and to examine their correlation with the severity of liver disease.
METHODS: Twenty-six patients with alcoholic liver cirrhosis were studied. Serum levels of NO^. and plasma levels of cGMP and GSH were measured in 7 patients with compensated alcoholic cirrhosis (Child-Pugh A) and 19 patients with advanced cirrhosis (Child-Pugh B and C). The model for end-stage liver disease (MELD) score was evaluated. Sixteen healthy volunteers served as controls. Liver enzymes and creatinine levels were also tested.
RESULTS: NO^. and cGMP levels were higher in patients with Child-Pugh B and C cirrhosis than in Child-Pugh A cirrhosis or controls (NO^.: 21.70 ± 8.07 vs 11.70 ± 2.74; 21.70± 8.07 vs 7.26 ± 2.47 μmol/L, respectively; P 〈 0.001) and (cGMP: 20.12 ± 6.62 vs 10.14 ± 2.78; 20.12 ± 6.62 vs 4.95 ± 1.21 pmol/L, respectively; P 〈 0.001). Total glutathione levels were lower in patients with Child-Pugh B and C cirrhosis than in patients with Child-Pugh A cirrhosis or controls (16.04 ± 6.06 vs 23.01 ± 4.38 or 16.04 ± 6.06 vs 66.57 ±26.23 μmol/L, respectively; P 〈 0.001). There was a significant correlation between NO^. and cGMP levels in all patients with alcoholic cirrhosis. A significant negative correlation between reduced glutathione/glutathione disulfide and the MELD score was found in all cirrhotic patients.
CONCLUSION: Our results suggest a role for oxidative stress in alcoholic liver cirrhosis, which is more significant in decompensated patients with higher levels of NO^. and cGMP and lower GSH levels than in compensated and control patients. Altered mediator levels in decompensated patients may influence the hemodynamic changes in and progression of liver disease.  相似文献   
82.
目的 探讨血小板源性生长因子-C(plelet-derived growth fctor-C,PDGF-C)和血小板源性生长因子-D(plelet-derived growth fctor-D,PDGF-D)与IgA肾病患者不同程度肾间质纤维化的关系及意义.方法 将50例肾组织标本按肾间质纤维化程度分为4组(对照组、轻度组、中度组、重度组).应用免疫组化方法检测各组PDGF-C及PDGF-D的表达,并将PDGF-C/-D的表达情况与肾间质纤维化程度及临床指标(24h尿蛋白、尿素氮、肌酐)进行相关性分析.结果 IgA肾病患者肾组织PDGF-C/-D的表达水平明显高于对照组(P<0.05),且与肾间质纤维化的程度成正相关(r=0.654和r=0.571,P<0.01).此外,IgA肾病肾组织PDGF-C/-D的表达与血尿素氮(BUN)及血肌酐(Scr)水平呈正相关(P<0.05),与24h尿蛋白定量无明显相关性.结论 随着肾小管间质病变程度的加重,PDGF-C、PDGF-D的表达量明显上调,PDGF-C/-D可能在IgA肾病肾间质纤维化的发生、发展过程中起着重要的作用.  相似文献   
83.
Sclerosing mesenteritis is a rare condition that is characterized by fibrosis affecting mainly small-bowel mesentery, which in extensive cases may mimic advanced intra-abdominal malignancy. Establishing the diagnosis in such cases is a clinical and histopathologic challenge. We report the successful management of a case of extensive sclerosing mesenteritis with occult ileal perforation, which was possibly the triggering cause. Severe complications occurred as a result of both the disease itself and its surgical treatment. Despite the complex course and life-threatening complications, a good prognosis can be expected. Although occasional recovery has been attributed to spontaneous regression and response to immunosuppressive therapy, a search for, and full eradication of, possible triggering focus is of paramount importance.Reprints are not available.  相似文献   
84.
85.
Aims Aortic stenosis (AS) is characterized by extensive remodellingof the valves, including infiltration of inflammatory cells,extracellular matrix degradation, and fibrosis. The molecularmechanisms behind this adverse remodelling have remained obscure.In this article, we study whether cathepsin G, an angiotensinII (Ang II)-forming elastolytic enzyme, contributes to progressionof AS. Methods and results Stenotic aortic valves (n=86) and controlvalves (n=17) were analysed for cathepsin G, transforming growthfactor-ß1 (TGF-ß1), and collagens I andIII with RT–PCR and immunohistochemistry. Valvular collagen/elastinratio was quantified by histochemistry. In stenotic valves,cathepsin G was present in mast cells and showed increased expression(P<0.001), which correlated positively (P<0.001) withthe expression levels of TGF-ß1 and collagens I andIII. TGF-ß1 was also present in mast cell-rich areasand cathepsin G induced losartan-sensitive TGF-ß1expression in cultured fibroblasts. Collagen/elastin ratio wasincreased in stenotic valves (P<0.001) and correlated positivelywith smoking (P=0.02). Nicotine in cigarette smoke activatedmast cells and induced TGF-ß1 expression in culturedfibroblasts. Fragmented elastin was observed in stenotic valvescontaining activated cathepsin G-secreting mast cells and innormal valves treated with cathepsin G. Conclusion In stenotic aortic valves, mast cell-derived cathepsinG may cause adverse valve remodelling and AS progression.  相似文献   
86.
目的:在细胞水平探索miR-21在调控TGF-β1诱导的大鼠骨髓间充质干细胞向肌成纤维细胞分化中的作用。方法:全髓培养法培养原代大鼠骨髓间充质干细胞,培养至第三代时用TGF-β1分组诱导培养,检测TGF-β1对大鼠BMSCs促纤维化的作用及该过程中不同浓度梯度TGF-β1诱导以及不同时间段miR-21的表达变化;通过转染miR-21 mimics(高表达)不同时间点检测其对α-SMA表达的影响。结果:TGF-β1能促进大鼠骨髓间充质干细胞向成纤维,肌成纤维细胞分化;大鼠骨髓间充质干细胞向成纤维,肌成纤维细胞分化后miR-21表达上调;上调miR-21能促进大鼠BMSCs的纤维化作用。结论:miR-21 mimics能够促进大鼠BMSCs的纤维化作用。  相似文献   
87.
Objective Liver fibrosis is an important predictor of mortality in nonalcoholic fatty liver disease(NAFLD). Peripheral artery disease(PAD) and liver fibrosis share many common metabolic dysfunctions.We aimed to explore the association between PAD and risk of fibrosis deterioration in NAFLD patients.Methods The study recruited 1,610 NAFLD patients aged ≥ 40 years from a well-defined community at baseline in 2010 and followed up between August 2014 and May 2015. Fibrosis deterioration was defined as the NAFLD fibrosis score(NFS) status increased to a higher category at the follow-up visit.PAD was defined as an ankle-brachial index of 0.90 or 1.40.Results During an average of 4.3 years' follow-up, 618 patients progressed to a higher NFS category.PAD was associated with 92% increased risk of fibrosis deterioration [multivariable-adjusted odds ratio(OR): 1.92, 95% confidence interval(CI): 1.24, 2.98]. When stratified by baseline NFS status, the OR for progression from low to intermediate or high NFS was 1.74(95% CI: 1.02, 3.00), and progression from intermediate to high NFS was 2.24(95% CI: 1.05, 4.80). There was a significant interaction between PAD and insulin resistance(IR) on fibrosis deterioration(P for interaction = 0.03). As compared with non-PAD and non-IR, the coexistence of PAD and IR was associated with a 3.85-fold(95% CI: 2.06, 7.18) increased risk of fibrosis deterioration.Conclusion PAD is associated with an increased risk of fibrosis deterioration in NAFLD patients,especially in those with IR. The coexistence of PAD and IR may impose an interactive effect on the risk of fibrosis deterioration.  相似文献   
88.
Background and purposePulmonary fibrosis (PF) is a progressing lung injury initiated by pulmonary inflammation (PI). Bleomycin (BLM) is the most common pathogenesis of PF through early PI and extensive extracellular matrix deposition. This study is aimed to determine whether NO-releasing KMUP-1 inhibits PI and PF, and if so, the benefits of KMUP-1S resulted from simvastatin (SIM)-bonding to KMUP-1.Experiment approachC57BL/6 male mice were intra-tracheally administered BLM (4 U/kg) at day 0. KMUP-1 (1–5 mg/kg), KMUP-1S (2.5 mg/kg), SIM (5 mg/kg), Plus (KMUP-1 2.5 mg/kg + SIM 2.5 mg/kg), and clarithromycin (CAM, 10 mg/kg) were orally and daily administered for 7 and 28 days, respectively, to mice, sacrificed at day-7 and day-28 to isolate the lung tissues, for examining the inflammatory and fibrotic signaling and measuring the cell population and MMP-2/MMP-9 activity in broncholaveolar lavage fluid (BAL).Key resultsKMUP-1 and KUP-1S significantly decreased neutrophil counts in BAL fluid. Fibroblastic foci were histologically assessed by H&E and Masson's trichrome stain and treated with KMUP-1 and references. Lung tissues were determined the contents of collagen and the expressions of TGF-β, α-SMA, HMGB1, CTGF, eNOS, p-eNOS, RhoA, Smad3, p-Smad3, MMP-2 and MMP-9 by Western blotting analyses, respectively. These changes areregulated by NO/cGMP and inhibited by various treatments. KMUP-1 and KMUP-1S predominantly prevented HMGB1/MMP-2 expression at day-7 and reduced TGF-β/phosphorylated Smad3 and CTGF at day-28.Conclusions and implicationsKMUP-1 and KMUP-S restore eNOS, inhibit iNOS/ROCKII/MMP-2/MMP-9, attenuate histologic collagen disposition and reduce BALF inflammatory cells, potentially useful for the treatment of BLM-lung PF.  相似文献   
89.
Cadmium is a potential environmental and industrial pollutant affecting human tissues and organs including liver and testes. The protective role of fenugreek seed powder (FSP) was investigated in male rats subjected to cadmium-induced testicular injury and hepatic dysfunction. Testicular damage and hepatotoxicity were induced by oral administration of cadmium chloride (5 mg/kg body weight, once a day) for 7 weeks. FSP was given at 5% w/w in chow diet for 8 weeks, starting 1 week before cadmium administration. FSP intake significantly increased serum testosterone level and testis weight that were reduced by cadmium. FSP also compensated deficits in hepatic and testicular antioxidant defense system, interleukin-4 and nitric oxide levels, reduced serum liver function enzyme activities and suppressed lipid peroxidation in hepatic and testicular tissues resulted from cadmium administration. Additionally, FSP attenuated the cadmium-induced elevations in hepatic and testicular tumor necrosis factor-α and transforming growth factor-beta1 levels as well as cadmium deposition and hydroxyproline content. The protective effect afforded by FSP was mainly due its antioxidant, antifibrotic and anti-inflammatory effects. In conclusion, the results of the present work indicated that FSP may represent a promising medicinal herb to protect hepatic and testicular tissues from the detrimental effects of cadmium.  相似文献   
90.
《Seminars in immunology》2014,26(3):229-236
TNF-like weak inducer of apoptosis (TWEAK), a TNF family ligand, and its only known signaling receptor, FGF-inducible molecule-14 (Fn14), have emerged as a key molecular pathway regulating tissue responses after acute tissue injury and in contexts of chronic injury and disease, including autoimmunity, chronic inflammation, fibrosis, and malignancy. Usually dormant due to the low level of Fn14 expression in healthy tissues, this axis is specifically activated by the upregulation of Fn14 expression locally within injured tissues, thereby triggering a wide range of activities in tissue parenchymal and stromal cells as well as tissue progenitor cells. Current evidence supports that although transient TWEAK/Fn14 pathway activation may be beneficial for tissue repair after acute injury, excessive or sustained TWEAK/Fn14 activation due to repeated injury or chronic disease mediates significant tissue damage and pathological tissue remodeling. This paradigm for the dichotomous function of the TWEAK/Fn14 pathway is discussed, highlighting emerging findings, complexities, and implications for the treatment of tissue damage-associated pathologies and cancer.  相似文献   
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