首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3980篇
  免费   289篇
  国内免费   171篇
耳鼻咽喉   48篇
儿科学   125篇
妇产科学   141篇
基础医学   572篇
口腔科学   62篇
临床医学   522篇
内科学   874篇
皮肤病学   139篇
神经病学   261篇
特种医学   398篇
外科学   306篇
综合类   90篇
预防医学   186篇
眼科学   86篇
药学   339篇
  1篇
中国医学   15篇
肿瘤学   275篇
  2023年   19篇
  2022年   28篇
  2021年   90篇
  2020年   58篇
  2019年   88篇
  2018年   105篇
  2017年   92篇
  2016年   84篇
  2015年   125篇
  2014年   157篇
  2013年   213篇
  2012年   246篇
  2011年   267篇
  2010年   196篇
  2009年   180篇
  2008年   234篇
  2007年   297篇
  2006年   187篇
  2005年   176篇
  2004年   136篇
  2003年   114篇
  2002年   108篇
  2001年   89篇
  2000年   52篇
  1999年   80篇
  1998年   106篇
  1997年   95篇
  1996年   83篇
  1995年   67篇
  1994年   56篇
  1993年   57篇
  1992年   20篇
  1991年   37篇
  1990年   32篇
  1989年   64篇
  1988年   58篇
  1987年   47篇
  1986年   41篇
  1985年   33篇
  1984年   35篇
  1983年   16篇
  1982年   29篇
  1981年   19篇
  1980年   19篇
  1979年   14篇
  1978年   8篇
  1977年   20篇
  1976年   30篇
  1975年   16篇
  1974年   5篇
排序方式: 共有4440条查询结果,搜索用时 15 毫秒
1.
Lucio phenomenon is an atypical reaction of leprosy, characterized by vasculitic lesions that can mimic antiphospholipid syndrome (APS) clinically. Distinguishing the two can be difficult as antiphospholipid autoantibodies may be present in patients with leprosy. We report on a 32‐year‐old female patient presenting with a sudden onset of fever, hemorrhagic bullae, and skin necrosis on her lower legs. She was treated for APS due to the presence of antiphospholipid antibodies but had an inadequate response. A skin biopsy revealed thrombotic vasculopathy and necrotizing vasculitis associated with aggregation of foam cells in the perivascular area and subcutis, with acid‐fast bacilli in the histiocytes and blood vessel walls. Direct immunofluorescence showed IgM, C3, and fibrinogen deposition in the superficial and deep dermal blood vessels. The pathology confirmed the diagnosis of Lucio phenomenon, and appropriate therapy was given. It is essential to evaluate the patient comprehensively, including clinical, serological, and pathological aspects, to obtain the correct diagnosis.  相似文献   
2.
高效液相色谱法测定人血浆中阿莫西林浓度及药代动力学   总被引:6,自引:0,他引:6  
谭力  周继红  罗楠  袁倚盛 《药学学报》1997,32(7):558-560
高效液相色谱法测定人血浆中阿莫西林浓度及药代动力学谭力周继红罗楠袁倚盛(南京军区南京总医院中心仪器分析科,南京210001)阿莫西林(amoxicilin)为β内酰胺类抗生素,其抗菌谱广,口服受食物影响小,对大多数病人耐受性良好,因而在临床上得以广泛...  相似文献   
3.
Elimination of antibiotic-resistant plasmids by quinolone antibiotics   总被引:2,自引:0,他引:2  
Of 7 plasmids we tested, the plasmid pORF2 was eliminated in vitro with the most efficiency by treatment with subinhibitory concentrations of novobiocin, coumermycin and 10 quinolones. It showed a cure rate of 43% by enoxacin; 12% by novobiocin, pefloxacin, ciprofloxacin and CI-934; 7% by coumermycin and ofloxacin; 9% by amifloxacin; and 4% by AM-833. On the other hand, pSC194, pBR322 and pMH612 were poorly cured in vitro by quinolones, except pSC194 which was cured 33% by enoxacin. R1, pP1603, and pUB110 were unaffected by the treatment. Mice were challenged intraperitoneally with a 2XLD50 of Escherichia coli carrying the ORF2 plasmid and were treated per os with 1 X or 1/2 X ED50 of either enoxacin or CI-934. The frequency of loss of ampicillin resistance determined 3 h after treatment shows curing effects of 92% for CI-934, 89% for enoxacin and 20% for untreated control.  相似文献   
4.
W C Hsiao  P Braun  E R Becker  S R Thomas 《JAMA》1987,258(6):799-802
This article describes the design and methods of a study currently under way to develop a Resource-Based Relative Value Scale (RBRVS); an alternative basis for establishing the payment rate for the services and procedures (S/Ps) of physicians in medical and surgical specialties. Physician resource inputs to be measured include (1) S/P time, (2) pre-S/P and post-S/P times, (3) intensity, (4) practice costs, including malpractice premiums, and (5) the cost of specialty training. These five factors will be combined to produce an RBRVS denominated in nonmonetary units. In the initial phase of the study, data on time and intensity will be obtained through a national survey of physicians who perform these S/Ps. In the second, consensus phase of the project, the investigators will convene a panel of representatives of the medical profession, third-party payers, consumers, and other interested parties to examine areas of agreement and disagreement as to how an RBRVS should be used for policy purposes. The final results of this study are expected by the summer of 1988.  相似文献   
5.
We report MRI and angiographic findings of an unusual giant arachnoid granulation in the left sigmoid sinus in a boy with headache. Its signal intensity was lower than that of cerebral cortex on T1-weighted images and higher on T2 weighting, mimicking dural sinus thrombosis. Received: 17 February 1997 Accepted: 17 February 1997  相似文献   
6.
BACKGROUND AND PURPOSE: Marine luminous bacteria were isolated and identified from samples in shallow coastal waters of Taiwan during the relatively warm seasons. METHODS: Identification of the luminous isolates was performed based on differences of phenotypic and genotypic characteristics together with data from phylogenetic analysis. RESULTS: Twenty seven strains of marine luminous bacteria were isolated. They were divided into five types based on differences of phenotypic characteristics. However, they could be clustered into only two genotypes according to the analysis of restriction patterns of polymerase chain reaction-amplified 16S rRNA genes digested with various restriction enzymes. The characterization data together with the 16S rRNA gene-based phylogenetic analysis revealed that the isolates included in phenotype I (seven isolates) could be Photobacterium leiognathi, and those included in phenotypes II-V (twenty isolates) might be classified as Vibrio harveyi. However, phylogeny based on gyrB sequences indicated that phenotypes II-V could be classified into two species, V. harveyi and Vibrio campbellii. CONCLUSION: Culturable luminous bacteria in the shallow coastal waters of Taiwan during the sampling period are dominated by V. harveyi/campbellii and P. leiognathi, and the former species appeared to be more prevalent and numerous than the latter species in general.  相似文献   
7.
Gerstmann-Str?ussler-Scheinker disease (GSS) is a rare, dominantly inherited neurodegenerative disease that can sometimes be transmitted to experimental animals through intracerebral inoculation of brain homogenates from patients. Substitution of leucine for proline at codon 102 of the prion protein gene has been found in several families with the disease; this mutation is genetically linked to GSS. Mice containing murine prion protein transgenes with this mutation spontaneously develop neurologic symptoms of ataxia, lethargy, and rigidity accompanied by spongiform degeneration throughout the brain. Thus, many of the clinical and pathological features of the GSS have been reproduced in this transgenic mouse paradigm; to our knowledge, this study illustrates, for the first time, that a neurodegenerative process similar to a human disease can be genetically modeled in animals. Whether or not this transgenic mouse model of GSS may facilitate the understanding of common neurodegenerative disorders such as Alzheimer disease remains to be established.  相似文献   
8.
9.
Adverse reaction to intravenous gadoteridol   总被引:1,自引:0,他引:1  
  相似文献   
10.
Propionic acidemia is a rare hereditary disease which is an autosomal recessive disorder. Defect of propionyl CoA carboxylase results in abnormal accumulation of propionate and its metabolites which interfere the pathway of glycine cleavage and the urea cycle. This organic acidemia is characterized by a wide spectrum of clinical and biochemical findings, including recurrent vomiting, difficult feeding, lethargy, hypotonia, metabolic ketoacidosis, hyperglycinemia and hyperammonemia during the acute episodes. We present a male newborn infant who sustained this disorder and was managed successfully with blood exchange transfusion, peritoneal dialysis, supplemented with sodium benzoate and sodium bicarbonate therapy. Urine gas chromatography disclosed significant elevation of propionate and its metabolites which subsided 2 days after peritoneal dialysis. Special designed formula was then given with restriction of protein intake and supplement with sodium benzoate and sodium carbonate. Prenatal genetic counseling is necessary in further pregnancy. Diagnosis can be obtained when propionyl CoA carboxylase activity is low in cultured amniotic fluid cells or chorion villi sample or when there is abnormally high methylcitrate level in amniotic fluid.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号