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991.
Infections caused by Rasamsonia argillacea complex have been reported in various clinical settings. Cystic fibrosis (CF) is one of the main underlying conditions. An observational cohort study of CF patients with Rasamsonia in respiratory samples was conducted. Eight isolates from 6 patients were identified as R. argillacea complex and tested for antifungal susceptibility. All isolates had high MICs to voriconazole and posaconazole and low MECs to echinocandins. Four patients experienced lung function decline in the year preceding first Rasamsonia isolation. This continued in the year following first isolation in 3 out of 4 cases. Antifungal therapy was initiated in 2 patients, to which only one exhibited a clinical response. Three out of 6 patients died within 3 years of isolating Rasamsonia. Genotyping suggests that similar genotypes of Rasamsonia can persist in CF airways. Consistent with other fungi in CF, the clinical impact of airway colonisation by Rasamsonia is variable. In certain patients, Rasamsonia may be able to drive clinical decline. In others, though a clear impact on lung function may be difficult to determine, the appearance of Rasamsonia acts as a marker of disease severity. In others it does not appear to have an obvious clinical impact on disease progression.  相似文献   
992.
OBJECTIVE: It has been observed that the cytopathic changes in hairy leukoplakia (HL) correlate with ultra-structural evidence of intra-keratinocyte herpes-type viral particles. In situ hybridization is considered to be the definitive confirmation of Epstein-Barr virus (EBV)-induced HL. This study evaluated the consistency of histopathological findings, which many believe to be diagnostic, with in situ hybridization for EBV-DNA in 60 patients with lesions clinically suggestive of HL.
MATERIALS AND METHODS: Hematoxylin and eosin (H&E)-stained sections were reviewed independently by three oral pathologists who did not know the hybridization results. The presence in keratinocytes of nuclear inclusions and/or homogenization, believed to be specific for EBV in these lesions, was used as an indicator for infection. Cytoplasmic changes were evaluated separately.
RESULTS: With in situ hybridization, 48 cases were positive and 12 were negative. When the two methods were compared, pathologist concurrence ranged from 83% to 92%. False negatives ranged from 6% to 19%, and false positives ranged from 8% to 25%. Cytoplasmic ballooning, homogenization, and perinuclear clearing were evident in all cases of hybridization-confirmed HL; however, these changes were also noted in 75% (9/12) of the cases with negative hybridization results. Most confirmed HL cases exhibited both nuclear homogenization and inclusions, although the former was more consistently seen.
CONCLUSION: Cytoplasmic changes did not agree well with EBV-DNA hybridization results, whereas nuclear changes demonstrated good, but not complete, agreement. In appropriate clinical settings, the finding of nuclear inclusions and/or homogenization may be of diagnostic value. However, because the potential for false positives and negatives is high, H&E cytopathology should not be used as a substitute for in situ hybridization in the definitive diagnosis of oral hairy leukoplakia.  相似文献   
993.
994.

Background

Multiple sclerosis is a chronic disease of uncertain aetiology. Variations in its disease course make it difficult to impossible to accurately determine the prognosis of individual patients. The Sylvia Lawry Centre for Multiple Sclerosis Research (SLCMSR) developed an "online analytical processing (OLAP)" tool that takes advantage of extant clinical trials data and allows one to model the near term future course of this chronic disease for an individual patient.

Results

For a given patient the most similar patients of the SLCMSR database are intelligently selected by a model-based matching algorithm integrated into an OLAP-tool to enable real time, web-based statistical analyses. The underlying database (last update April 2005) contains 1,059 patients derived from 30 placebo arms of controlled clinical trials. Demographic information on the entire database and the portion selected for comparison are displayed. The result of the statistical comparison is provided as a display of the course of Expanded Disability Status Scale (EDSS) for individuals in the database with regions of probable progression over time, along with their mean relapse rate. Kaplan-Meier curves for time to sustained progression in the EDSS and time to requirement of constant assistance to walk (EDSS 6) are also displayed. The software-application OLAP anticipates the input MS patient's course on the basis of baseline values and the known course of disease for similar patients who have been followed in clinical trials.

Conclusion

This simulation could be useful for physicians, researchers and other professionals who counsel patients on therapeutic options. The application can be modified for studying the natural history of other chronic diseases, if and when similar datasets on which the OLAP operates exist.
  相似文献   
995.
目的:观察天麻注射液和续断注射液对氟哌啶醇诱导痴呆模型大鼠抗氧化酶活性作用,探讨两种药物延缓衰老可能的作用机制。方法:实验于2003/2005在湖北民族学院医学实验中心和华中科技大学同济医学院动物实验中心完成。实验分组:通过对雄性Wistar大鼠进行电跳台行为学训练,选择训练合格的大鼠40只,随机分为对照组、模型组、天麻注射液组和续断注射液组。实验干预:模型组腹腔注射氟哌啶醇注射液0.001mg/g,2次/d,持续3d。天麻注射液组腹腔注射氟哌啶醇注射液0.001mg/g,2次/d,持续7d,第4天腹腔注射天麻注射液0.003mL/g。续断注射液组用同样的方法注射续断注射液。对照组腹腔注射生理盐水,2次/d,持续7d。实验评估:运用回避反映箱观察各组大鼠行为学的变化,测定各组大鼠血、肝、肾、海马、大脑皮质超氧化物歧化酶和谷胱甘肽过氧化物酶活性。结果:实验大鼠40只均进入结果分析。①3min内犯错次数:模型组均在2次以上,天麻注射液组和续断注射液组明显降低,与对照组接近。②天麻注射液组和续断注射液组血、肝、肾、海马、大脑皮质中超氧化物歧化酶活性明显高于模型组和对照组(P<0.01)。天麻注射液组各组织中超氧化物歧化酶活性明显高于续断注射液组(P<0.01)。③天麻注射液组和续断注射液组血、肝、肾、海马、大脑皮质中谷胱甘肽过氧化物酶活性明显高于模型组和对照组(P<0.01)。天麻注射液组血液中谷胱甘肽过氧化物酶活性高于续断注射液组(P<0.05)。续断注射液组肝、海马中谷胱甘肽过氧化物酶活性高于天麻注射液组(P<0.05)。在肾和大脑皮质中谷胱甘肽过氧化物酶活性天麻注射液组和续断注射液组相似(P>0.05)。结论:①天麻和续断具有明显的抗氧化作用,天麻的抗氧化作用强于续断。②抗氧化作用可能是两种药物的抗衰老机制之一。  相似文献   
996.
Aim: Little is known about pyridoxine nutriture of children treated with isoniazid (INH) regimens. This study documents plasma pyridoxal 5′‐phosphate (PLP) concentrations in children, HIV‐infected and HIV‐uninfected, receiving INH regimens. Methods: Children from the Western Cape of South Africa hospitalized for tuberculosis (TB) management were studied. Plasma PLP concentrations were determined on enrolment, 1‐month after commencing TB treatment, and again after 4‐month’s treatment. The children received a supplement meeting pyridoxine requirements. Results: Nineteen HIV‐infected and 33 HIV‐uninfected children received INH (dosage range 4–20 mg/kg) daily. Mean PLP plasma concentrations on enrolment were 8.32 (SD 6.75) ng/mL and 11.28 (SD 3.02) ng/mL in HIV‐infected and HIV‐uninfected children, respectively (p = 0.11) and after 4‐month’s treatment 6.75 (SD 2.71) ng/mL and 14.76 (SD 7.96) ng/mL (p < 0.001). On enrolment 9 (50%) HIV‐infected and 5 (15%) HIV‐uninfected children (p = 0.016) had suboptimal PLP concentrations (<6 ng/mL); after 4‐month’s treatment 8 (42%) and 2 (6%) (p = 0.004). Conclusion: Plasma PLP concentrations in children treated for TB were low on enrolment in HIV‐infected and HIV‐uninfected children; after 4‐month’s treatment low values were still common in HIV‐infected children. Additional pyridoxine supplementation of malnourished children treated for tuberculosis is advisable, particularly those HIV‐infected.  相似文献   
997.
998.
Schnyder's crystalline corneal dystrophy (SCCD) is an autosomal dominant eye disease characterized by a bilateral clouding of the central cornea, arcus lipoides and/or visible crystalline deposits of cholesterol in the stroma. There is accumulation of phospholipid, unesterified cholesterol and cholesterol ester in the corneal stroma; this is believed to be due to an imbalance in the local factors affecting lipid/cholesterol transport or metabolism. The cellular mechanism of abnormal lipid transport and metabolism in SCCD is of interest due to its potential involvement in atherosclerosis, and its implications for the pathogenesis of cerebrovascular, coronary and peripheral vascular disease as well as corneal opacification. To determine the chromosomal location of the SCCD locus, genome-wide linkage analysis has been performed in two large Swede-Finn kindreds recently identified in central Massachusetts. After analysing 300 microsatellite markers > 90% of the genome was excluded from linkage to the SCCD locus. We now report the chromosomal assignment of the gene for SCCD in both families to be 1p34.1-p36; the maximum multipoint lod- score was 8.48 in the interval between D1S214 and D1S503. From haplotype analysis, the SCCD locus lies in the 16 cM interval between markers D1S2663 and D1S228. Several candidate genes for SCCD have been localized to the 1p34.1-p36 interval.   相似文献   
999.
Adenovirus-mediated gene transfer to muscle is a promising technology for gene therapy of Duchenne muscular dystrophy (DMD). However, currently available recombinant adenovirus vectors have several limitations, including a limited cloning capacity of approximately 8.5 kb, and the induction of a host immune response that leads to transient gene expression of 3-4 weeks in immunocompetent animals. Gene therapy for DMD could benefit from the development of adenoviral vectors with an increased cloning capacity to accommodate a full-length (approximately 14 kb) dystrophin cDNA. This increased capacity should also accommodate gene regulatory elements to achieve expression of transduced genes in a tissue-specific manner. Additional vector modifications that eliminate adenoviral genes, expression of which is associated with development of a host immune response, might greatly increase long-term expression of virally delivered genes in vivo. We have constructed encapsidated adenovirus minichromosomes theoretically capable of delivering up to 35 kb of non-viral exogenous DNA. These minichromosomes are derived from bacterial plasmids containing two fused inverted adenovirus origins of replication embedded in a circular genome, the adenovirus packaging signals, a beta-galactosidase reporter gene and a full-length dystrophin cDNA regulated by a muscle-specific enhancer/promoter. The encapsidated minichromosomes are propagated in vitro by trans-complementation with a replication-defective (E1 + E3 deleted) helper virus. We show that the minichromosomes can be propagated to high titer (> 10(8)/ml) and purified on CsCl gradients due to their buoyancy difference relative to helper virus. These vectors are able to transduce myogenic cell cultures and express dystrophin in myotubes. These results suggest that encapsidated adenovirus minichromosomes may be useful for gene transfer to muscle and other tissues.   相似文献   
1000.
Optically pure L-3(2-hydroxyphenyl) alanine(L-o-tyrosine ,Ⅲa,),L-3-(3-hydroxyphenyl) alanine(L-m-tyrosine,Ⅲb )and L-3-(4-hydroxyphenyl )alanine(L-p-tyrosine,Ⅲc )were synthesized by the stereocontrolled amination of corresponding hydroxycinnamic acld(Ⅱ)catalyzed by L-phenylalanine ammonia-lyase(PAL,EC4.3.1.5 )contained in Rhodoterula rubramycelium. The amination of compound Ⅱ was completed in aqueous ammonia solution( 6.4mol·L-1,pH10.5, 30℃) with the conversion of 74.9%(Ⅱa),21.1%(Ⅱb)and 20.6%(Ⅱc)respectively.The absolute configuration of the products Ⅲa~c were confirmed by circular dichroism(CD),and chiral high-performance ligand exchange chromatography(HPLEC)showed that productsⅢ were optically pure L-isomers.  相似文献   
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