全文获取类型
收费全文 | 1844篇 |
免费 | 88篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 42篇 |
儿科学 | 131篇 |
妇产科学 | 20篇 |
基础医学 | 246篇 |
口腔科学 | 70篇 |
临床医学 | 95篇 |
内科学 | 346篇 |
皮肤病学 | 31篇 |
神经病学 | 104篇 |
特种医学 | 44篇 |
外科学 | 285篇 |
综合类 | 58篇 |
一般理论 | 1篇 |
预防医学 | 60篇 |
眼科学 | 56篇 |
药学 | 196篇 |
中国医学 | 10篇 |
肿瘤学 | 140篇 |
出版年
2023年 | 9篇 |
2022年 | 18篇 |
2021年 | 65篇 |
2020年 | 35篇 |
2019年 | 34篇 |
2018年 | 47篇 |
2017年 | 38篇 |
2016年 | 46篇 |
2015年 | 46篇 |
2014年 | 64篇 |
2013年 | 77篇 |
2012年 | 134篇 |
2011年 | 187篇 |
2010年 | 79篇 |
2009年 | 54篇 |
2008年 | 108篇 |
2007年 | 120篇 |
2006年 | 108篇 |
2005年 | 85篇 |
2004年 | 84篇 |
2003年 | 81篇 |
2002年 | 70篇 |
2001年 | 35篇 |
2000年 | 32篇 |
1999年 | 35篇 |
1998年 | 11篇 |
1997年 | 18篇 |
1996年 | 7篇 |
1995年 | 6篇 |
1994年 | 5篇 |
1993年 | 9篇 |
1992年 | 19篇 |
1991年 | 12篇 |
1990年 | 9篇 |
1989年 | 6篇 |
1988年 | 9篇 |
1987年 | 19篇 |
1986年 | 14篇 |
1985年 | 10篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 9篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1977年 | 5篇 |
1974年 | 5篇 |
1973年 | 6篇 |
1971年 | 5篇 |
排序方式: 共有1935条查询结果,搜索用时 31 毫秒
1.
Surendra Singh Susan John Thykkoothathil Pappy Joseph Thilak Soloman 《Journal of Medical Imaging and Radiation Oncology》2003,47(2):127-134
We report the MRI features in a series of four patients with primary angiitis of the central nervous system (PACNS). Based on MRI features, clinical presentation, paraclinical investigations and laboratory tests, including cerebrospinal fluid (CSF) analysis, various differentials were considered. In two patients with MRI findings of cortical, subcortical and deep white matter lesions, lack of mass effect, focal areas of bleed and heterogeneous parenchymal, leptomeningeal or pial enhancement and a normal magnetic resonance angiography, a differential diagnosis of primary angiitis of the CNS was also considered. In all patients, an open brain biopsy was advised to establish a definitive diagnosis of PACNS. Here, we briefly discuss the MRI features, correlation with clinical presentation and paraclinical parameters for the diagnosis of this entity. We also briefly review the literature. 相似文献
2.
3.
4.
Richard B. Dewey Jr Surendra D. Rao Stephanie L. Holmburg Ronald G. Victor 《European journal of neurology》1998,5(6):593-599
Eight patients with parkinsonism who developed severe orthostatic sypotension, were treated with oral ergotamine/caffeine. Significant long-term improvement in standing systolic blood pressure and symptoms of syncope and light-headedness were observed in four of these patients. One patient in whom the drug was effective discontinued it because of nausea. Another lost benefit after 2 weeks of sucessful therapy. Significant supine systolic hypertension occureed in only one patient, which was easily managed by nifedipine given at night. Symptoms or signs of ergotism were not observed. Oral ergotamine/caffeine should be considered as a cost-effective teratment for refactory orthostatic hypotension in carefully selected patients with parkinsonism. 相似文献
5.
Chandradhar Dwivedi Radhey S. Misra Anshumali Chaudhari Surendra S. Parmar 《Journal of the National Medical Association》1980,72(10):953-955
Monoamine oxidase inhibitory and anticonvulsant properties of 2-substituted styryl-6-bromo-3-(4-ethylbenzoate/4 benzhydrazide)-4-quinazoles are studied. All styryl quinazolone esters except compound number 9 exhibited monoamine oxidase inhibitory properties during oxidative deamination of kynuramine. Corresponding hydrazides were found to have relatively higher activity. All these quinazolones were able to protect against pentylenetetrazol induced seizures. These observations in general do not prove that monoamine oxidase inhibitory properties represent the biochemical basis for the anticonvulsant activity of these compounds. 相似文献
6.
Rapid detection and quantitation of hepatitis B virus DNA by real-time PCR using a new fluorescent (FRET) detection system. 总被引:6,自引:0,他引:6
Sani Hussein Aliyu Muktar Hassan Aliyu Hamisu M Salihu Surendra Parmar Hamid Jalal Martin David Curran 《Journal of clinical virology》2004,30(2):191-195
BACKGROUND: The diagnosis of hepatitis B virus (HBV) has until recently been based on traditional serologic methods targeting viral antigens and antibodies to viral proteins. The development of molecular methods allowing for the quantitation of HBV DNA is proving clinically valuable for monitoring therapy and detecting early treatment failures. OBJECTIVES: Here we report a new real-time (LightCycler) quantitative PCR for the detection of HBV DNA based on sequence specific hybridisation probes (designed in-house), targeting the HBV surface antigen. STUDY DESIGN: The assay was evaluated using a 10-fold dilution series of standard HBV DNA [Eurohep standard reference 1, genotype A, HBsAg subtype adw with a unitage of 10(6) WHO. i.u./ml] and 89 clinical serum samples. The performance was measured against a quantified standard HBV DNA working reagent (NIBSC code 98/780) and the sensitivity compared with our conventional thermal-block PCR. RESULTS AND CONCLUSION: Real-time PCR detected HBV DNA in 45% (40/89) and thermal-block PCR in 16% (14/75) of clinical samples. Results for 26 samples were below the detection limit of the thermal-block PCR but could be quantified by real-time (LightCycler) PCR. The LightCycler assay was at least 5 logs more sensitive than thermal-block PCR and could detect HBV in a linear range between 5 and 10(7) i.u. per reaction. The broad generic nature of the PCR primers coupled with the enhanced sensitivity and specificity of the fluorescent hybridisation probes makes this assay potentially valuable for both routine diagnostic and epidemiological work. 相似文献
7.
F. J. Taylor Varadaraj Shenoy C. P. Olinger J. F. Wasserman 《Medical & biological engineering & computing》1979,17(4):443-448
Intercranial aneurysm present an especially serious clinical problem, since their rupture generally results in death or permanent
brain damage. Recent work, conducted by the authors, indicated that this anomaly can be detected using spectral signature
analysis. A low-cost turnkey noninvasive aneurysm-detection system is being tested for this purpose. Using polarity-coincident
noise-added one-bit correlators, aneurysms have been successfully detected. 相似文献
8.
A rare case of a segmental small intestinal (jejunal) lipomatosis is described. A 33-year-old male was admitted with a clinical diagnosis of an acute intestinal obstruction. A plain erect abdominal x-ray showed multiple air-fluid levels. On an exploratory laparotomy, a jejunojejunal intussusception was found secondary to a segmental submucosal lipomatosis. This was treated by a segmental resection and anastomosis, which resulted in a complete cure. Here we present this case with a review of the relevant literature. 相似文献
9.
Nagarkatti R Kumar R Sharma SK Ghosh B 《International archives of allergy and immunology》2004,134(3):206-212
BACKGROUND: Asthma is a complex airway disorder, and a number of genetic loci have been found to be associated with asthma. The 5q31-33 region is one of the most important loci linked to asthma and atopic disorders. However, association studies with candidate genes in this region, such as IL4, were inconclusive, as both positive and negative results were obtained in several populations studied. The aim of our case-control study was to determine the association between IL4 and asthma in North Indians. PATIENTS AND METHODS: Polymorphisms in the promoter and a dinucleotide repeat in the 2nd intron in IL4 were genotyped by sequencing and GeneScan analysis, respectively, in ethnically matched, unrelated patients (n = 171) and controls (n = 128), following the guidelines of the American Thoracic Society. RESULTS: The proximal promoter region of the IL4 gene was found to be invariant. Previously reported polymorphisms, -590 C/T and +33 C/T, were found to be absent in our population. The chi2 test using only large expected cell counts (more than 5% of the sample size) showed a significant association between allele size and disease status (chi2 = 38.08, d.f. = 6, p < 0.05). In addition, a significant difference was observed for the allele and genotype frequencies (p < 0.0005 and p = 0.0009, respectively) in the patient and the control groups using the Fisher-Freeman-Halton test. CONCLUSION: Our studies indicate that the promoter of the IL4 gene is invariant in our population. The case-control studies on the CA repeat polymorphism in the 2nd intron of the IL4 gene have shown interesting results and indicate the need for further family-based studies. 相似文献
10.