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991.
目的 研究syndecan-4对碱性成纤维细胞生长因子(bFGF)诱导人肾小球系膜细胞(HMC)增殖及细胞外基质(ECM)分泌的影响,并探讨syndecan-4-蛋白激酶Cα(PKCα)途径在其中的作用。 方法 免疫荧光方法观察syndecan-4在HMC上的表达。筛选有效的syndecan-4-siRNA转染HMC,噻唑蓝(MTT)比色法检测HMC在bFGF不同作用时间下的增殖差异;ELISA法检测细胞上清液中的Ⅰ、Ⅳ型胶原和纤连蛋白(FN)含量;荧光定量PCR观察syndecan-4和PKCα含量的变化。 结果 syndecan-4蛋白在HMC有表达。bFGF可促进HMC的增殖及FN、Ⅳ型胶原的分泌,使得每百万看家基因中PKCα拷贝数明显增加。转染syndecan-4 siRNA后,显著降低了HMC的增殖速度(48~60 h时点,P < 0.01)、ECM分泌(FN:24 h时点,P < 0.01,48~96 h,P < 0.05;Ⅳ型胶原:72~96 h时点,P < 0.05)及PKCα含量 (0 h时点,P < 0.05,12 ~48 h时点,P < 0.01)。 结论 syndecan-4参与调控bFGF诱导HMC的增殖及ECM分泌过程。syndecan-4-PKCα途径可能在其中扮演重要作用。  相似文献   
992.
目的:观察噻唑烷二酮(TZDs)对2型糖尿病(T2DM)伴代谢综合征(MS)患者治疗前后血清高敏C反应蛋白(hsCRP)、纤维蛋白原(FIB)水平的变化及其影响因素,探讨TZDs与糖、脂代谢和炎性因子的关系。方法:采用随机对照方法将50例T2DM伴MS的患者随机分为用TZDs治疗组和不用TZDs治疗组,进行为期2周的临床观察。结果:两组患者治疗2周后与基线值比较空腹血糖(FBG)、餐后2h血糖(2hBG)、总胆固醇(TC)、甘油三酯(TG)、hsCRP均下降,但以上指标在用TZDs治疗组差别具有显著性,而且hsCRP下降更有显著性,同时还发现用TZDs治疗组治疗前后比较纤维蛋白原(FIB)差别也具有非常显著性。2组患者治疗2周后组内和组间比较HDLC、LDLC无明显变化。结论:T2DM伴MS与慢性亚临床炎症密切相关,TZDs在降低血糖、调节血脂、改善胰岛素抵抗(IR)、提高胰岛素敏感性的同时还有明显抗炎作用。  相似文献   
993.
The purpose of this study was to determine the cost savings from a societal perspective for recombinant human Bone Morphogenetic Protein-2 (rhBMP-2) in grade III A and B open tibial fractures treated with a locked intramedullary nail and soft-tissue management in the UK, Germany, and France. Health care system costs (direct health care costs) and costs for productivity losses (indirect health care costs) were calculated using the raw data from the Bone Morphogenetic Protein Evaluation Group in Surgery for Tibial Trauma “BESTT study”. Return-to-work time for estimation of productivity losses was assumed to correspond with the time of fracture healing. For calculation of secondary interventions costs and productivity losses the respective 2007/2008 national tariffs for surgical procedures and average national wages for the UK, Germany, and France were used. For a 1 year perspective, overall treatment costs per patient after the initial surgery of the control vs. the rhBMP-2 group were €44,757 vs. €36,847 for the UK, €50,197 vs. €40,927 for Germany and €48,766 vs. €39,474 for France in favour of rhBMP-2 with overall savings overall savings per case of rhBMP-2 treatment of €7911 for the UK, €9270 for Germany, and €9291 for France which was mainly due to reduced productivity losses by significant faster fracture healing in the rhBMP-2 group (p = 0.01). These savings largely offset the upfront price of rhBMP-2 of €2266 (£1790) in the UK, €2970 in Germany, and €2950 in France. Total net savings can be estimated to be €9.6 million for the UK, €14.5 million for Germany, and €11.4 million for France. The results depend on the methodology used particularly for calculation of productivity losses and return-to-work time which was assumed to correspond with fracture healing time. In summary, despite the apparent high direct cost of rhBMP-2 in grade III A and B open tibial fractures, at a national level there are net cost savings from a societal perspective for all three countries.  相似文献   
994.
Although varicella is a common disease of childhood, renal complications are quite rare. We report here the interesting case of a-22 month-old boy exhibiting renal cortical necrosis related to an acquired protein S deficiency following varicella. Ten days after the vesicle eruption appearance, he presented with ecchymosed heels, oligoanuric kidney failure, anemia [hemoglobin (Hb) 78 g/L], schizocytosis (2.5%), but normal platelet count. Kidney sonography and magnetic resonance imaging evoked renal cortical necrosis. All together, these features suggested acquired protein S deficiency secondary to varicella. Strikingly, it was confirmed by a dramatic decrease in protein S plasma activity and a huge increase in immunoglobulin (Ig)G antibodies against protein S in the plasma. Anticoagulation therapy in addition with plasmapheresis and steroid pulses allowed a dramatic decrease in the antibodies against protein S and recovery of normal protein S activity. Undelayed diagnosis and treatment did not avoid kidney insufficiency but prevented life-threatening complications. In the light of this case report, protein S deficiency due to antibody inhibition should be carefully monitored anytime in the context of varicella when kidney insufficiency or necrosis occurs.  相似文献   
995.
Hong M  Zhang X  Hu Y  Wang H  He W  Mei H  Yu J  Guo T  Song S 《Thrombosis research》2009,123(3):556-564

Introduction

Few studies were concerned about searching for specific biomarkers for thromboembolic (arterial and venous) diseases by the use of Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOF-MS).

Materials and Methods

We screened for potential biomarkers in 69 plasma samples, including samples from 20 patients with idiopathetic deep vein thrombosis (DVT), 20 patients with acute myocardial infarction (AMI), and 29 healthy controls without a history of thromboembolism. Pretreated plasma samples were analyzed on the Protein Biology System IIc plus SELDI-TOF-MS (Ciphergen Biosystems, Fremont, CA). Proteomic spectra of mass to charge ratio (m/z) were generated by the application of plasma to immobilized metal affinity capture (IMAC-3) ProteinChip arrays activated with copper.

Results

A pattern of three biomarkers (m/z: 2 667, 5 914, and 6 890 Da, respectively) with a total accuracy of 100% was selected based on their collective contribution to the optimal separation between patients with AMI and healthy controls. Another spattern consisting of only one biomarker (m/z: 5 914 Da) could totally discriminate patients with DVT and control subjects. For further analysis between patients with AMI and those with DVT, a pattern of four biomarkers (m/z: 3 418, 5 271, 33 378, and 68 125 Da, respectively) was selected with a total accuracy of 82.5%.

Conclusions

Plasma proteomic profiling with SELDI-TOF-MS and ProteinChip technologies provides high sensitivity and specificity in discriminating patients with thrombosis and healthy subjects. The discovered biomarkers might show great potential for early diagnosis of thromboembolic diseases.  相似文献   
996.

Introduction

The present case-control study was designed in order to investigate the association between plasma protein Z (PZ) levels, the intron F G79A polymorphism and unexplained pregnancy loss.

Materials and Methods

51 women with at least two consecutive or three non-consecutive fetal losses between the 8th and 12th week of gestation and 47 apparently healthy parous women of reproductive age with no history of pregnancy loss (controls) were enrolled. Allele frequencies of the PZ intron F G79A polymorphism and PZ levels were measured.

Results

PZ levels (mg/L) were significantly lower in cases (mean±S.D. 1.28 ± 0.56) than controls (1.97 ± 0.76, p < 0.001) and in carriers of the A allele (1.46 ± 0.62), compared to GG homozygous subjects (1.72 ± 0.81, p = 0.044). A higher proportion of cases (41.2%) were PZ-deficient (< 1 mg/L), compared to controls (10.6%, p = 0.001). No significant difference in the frequency of at least one A allele carriers was observed between cases (39.2%) and controls (40.4%).

Conclusion(s)

It is possible that low PZ levels are a novel risk factor for unexplained recurrent miscarriage or fetal death. The presence of the F 79A allele is associated with significantly lower PZ levels, but, in the present study, was unrelated to unexplained early pregnancy loss.  相似文献   
997.
目的 检测胃腺癌组织和淋巴结转移灶中细胞骨架相关蛋白上皮钙黏素(E-cad)及埃兹蛋白(Ezrin)的表达,观察其与胃腺癌侵袭和转移的关系,探讨胃腺癌的浸润和转移机制.方法 用SP免疫组织化学法检测80例胃癌和40例淋巴结转移灶中E-cad和Ezrin的表达.结果 E-cad和Ezrin在癌旁正常胃黏膜上皮为胞膜表达,而在胃腺癌组织中E-cad出现胞膜、胞质两种表达形式,Ezrin在肿瘤细胞中则为胞质表达.在胃腺癌原发灶中,E-cad、Ezrin的表达与胃腺癌的分化程度相关.E-cad的膜表达及Ezrin的表达随分化程度降低而下降(P<0.01;P<0.05),E-cad的浆表达随分化程度降低而升高(P<0.01).E-cad浆表达的升高与浸润深度、淋巴结状态相关且在原发灶显著高于转移灶(P<0.01;P<0.05;P<0.01).在淋巴结转移灶中,E-cad的膜表达在淋巴结转移的早期阶段高于晚期阶段(P<0.05).另外,E-cad膜表达及Ezrin的表达呈正相关(P<0.01).结论 胃腺癌中E-cad的表达异常导致了细胞之间的黏附力下降,从而在胃腺癌的侵袭和转移中发挥重要作用.埃兹蛋白参与调节胃腺癌细胞的分化,可能通过与E-cadherin/catenin作用来调控肿瘤细胞的黏附和侵袭.  相似文献   
998.
Although 3-aminopropyltriethoxysilane (APTES) is widely adopted as a monolayer in biosensors, experimental silanization takes at least 1 h at high temperature. Therefore, the feasibility of the silanization with APTES in a short reaction time and at room temperature was investigated. The surface modification of glass slides using a self-assembled monolayer of APTES with a concentration of 10% was studied by immobilizing FITC. APTES was successfully immobilized on the glass slide. The effect of reaction temperature and time of silanization were investigated. Various silanization conditions of APTES were examined by contact angle measurement and fluorescence microscopy. The surface of glass patterns with a gold thin film as background was characterized by determining the fluorescent intensities following the immobilization of fluorescein isothiocyanate (FITC), protein A-FITC, antimouse IgG-FITC and sheep anti-bovine albumin-FITC. The normalized fluorescent intensity indicated that a short period (4 min) of silanization at 25°C suffices to form an APTES thin film by the immobilization of protein A on a glass surface. Such a condition does not require microheaters and temperature sensors in a microfluidic system, which will significantly reduce the manufacturing process, cost, and reaction time in the future.  相似文献   
999.

OBJECTIVE

To screen a publicly available immunohistochemistry (IHC) based web‐atlas, to identify key proteins in bladder cancer that might serve as potential biomarkers.

MATERIALS AND METHODS

The first version of the Human Protein Atlas (HPA 1.0), with 660 proteins, was visually examined to identify proteins with a variable staining pattern among the 12 tissue samples representing bladder cancer. None or limited previous characterization in bladder cancer, as well as a supportive Western blot, were also required. The selected proteins were then evaluated in an independent set of patient samples (106 tumour samples of differing stage and grade) represented in a tissue microarray (TMAi). The IHC expression of the identified proteins in the TMAi was scored and related to tumour stage and grade.

RESULTS

The expression profiles of the 13 proteins selected from the web‐atlas were confirmed in the TMAi. Expression patterns for seven proteins were significantly altered (P < 0.05) with higher stage and/or grade. Three of those (CN130, DSG3, PHF6) lack characterization in bladder cancer, whereas the remaining four proteins have previously been suggested as key proteins/potential biomarkers in cancer, some of them also in bladder cancer.

CONCLUSION

New candidate proteins for urinary bladder cancer were identified through screening of the publicly available HPA 1.0. Although further evaluation is necessary, this strategy is promising in the search for new biomarkers, with potential to improve the management of patients with this disease.  相似文献   
1000.
目的:应用增强型绿色荧光蛋白(EGFP)来标记葡萄糖调节蛋白78(GRP78),从而研究其与免疫细胞结合的情况。方法:通过在原核表达的GRP78的C末端连接一个EGFP来显示跟踪该蛋白的表达,进而通过流式细胞仪检测该蛋白同小鼠脾脏免疫细胞结合的情况。结果:GRP-EGFP融合蛋白分子量为126kD,Western Blot证实该蛋白表达正确,并且表达GRP78-EGFP的BL21菌在紫外光激发下发射出强烈的绿色荧光;与EGFP单体相比较,GRP78-EGFP主要与中性粒细胞相结合,其平均结合率为5.15%。结论:绿色荧光蛋白标记的GRP78蛋白在原核中的表达具有天然构象并能发挥标记目的蛋白的作用。  相似文献   
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