全文获取类型
收费全文 | 3436篇 |
免费 | 350篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 31篇 |
儿科学 | 102篇 |
妇产科学 | 45篇 |
基础医学 | 453篇 |
口腔科学 | 187篇 |
临床医学 | 242篇 |
内科学 | 724篇 |
皮肤病学 | 72篇 |
神经病学 | 181篇 |
特种医学 | 98篇 |
外科学 | 496篇 |
综合类 | 199篇 |
一般理论 | 1篇 |
预防医学 | 210篇 |
眼科学 | 145篇 |
药学 | 273篇 |
1篇 | |
中国医学 | 22篇 |
肿瘤学 | 321篇 |
出版年
2023年 | 42篇 |
2022年 | 65篇 |
2021年 | 132篇 |
2020年 | 96篇 |
2019年 | 103篇 |
2018年 | 117篇 |
2017年 | 104篇 |
2016年 | 120篇 |
2015年 | 138篇 |
2014年 | 155篇 |
2013年 | 157篇 |
2012年 | 251篇 |
2011年 | 214篇 |
2010年 | 120篇 |
2009年 | 124篇 |
2008年 | 162篇 |
2007年 | 156篇 |
2006年 | 143篇 |
2005年 | 139篇 |
2004年 | 168篇 |
2003年 | 103篇 |
2002年 | 112篇 |
2001年 | 81篇 |
2000年 | 83篇 |
1999年 | 76篇 |
1998年 | 33篇 |
1997年 | 27篇 |
1996年 | 25篇 |
1995年 | 15篇 |
1994年 | 28篇 |
1993年 | 16篇 |
1992年 | 35篇 |
1991年 | 42篇 |
1990年 | 55篇 |
1989年 | 36篇 |
1988年 | 33篇 |
1987年 | 35篇 |
1986年 | 34篇 |
1985年 | 31篇 |
1984年 | 27篇 |
1983年 | 18篇 |
1982年 | 12篇 |
1981年 | 9篇 |
1980年 | 10篇 |
1979年 | 34篇 |
1977年 | 14篇 |
1975年 | 7篇 |
1974年 | 7篇 |
1972年 | 11篇 |
1971年 | 9篇 |
排序方式: 共有3803条查询结果,搜索用时 15 毫秒
31.
Squamous cell carcinoma antigen as an adjunct tumour marker in primary carcinoma of the lung. 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《Journal of clinical pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
AIMS--To determine (1) the detection rate of primary carcinoma of the lung by serological assay of CEA (carcinoembryonic antigen); and (2) whether addition of seroassay of squamous cell carcinoma related antigen before treatment improves detection sensitivity. METHODS--A prospective study spanning 27 months was conducted at the University Hospital, Kuala Lumpur. Serum CEA (Abbott IMx) and serum squamous cell carcinoma antigen (Abbott IMx) from patients clinically suspected of having primary carcinoma of the lung, were assayed using the microparticle enzyme immunoassay method. RESULTS--Thirty seven cases of histologically confirmed primary lung carcinoma were studied. Of these, 17 were squamous cell carcinomas, 10 adenocarcinomas, nine small cell carcinomas, and one large cell carcinoma. The patients' ages ranged from 34-82 years. The male:female ratio was 3.6:1. Squamous cell carcinoma antigen was raised above the cutoff value of 1.5 ng/ml in 94.1% of squamous cell carcinomas, 20.0% of adenocarcinomas, and 11.1% of small cell carcinomas. By comparison, CEA was raised above the cutoff value of 3.0 ng/ml in 70.6% of squamous cell carcinomas, 77.8% of small cell carcinomas, and 100% of adenocarcinomas. CEA and squamous cell carcinoma antigen were not raised in the patient with large cell carcinoma and in 14 healthy volunteers. None of 15 patients with a variety of benign lung diseases showed a rise of CEA, while two patients--a 25 year old Indian woman with pneumonia and a 64 year old Malay man with bronchial asthma--had raised squamous cell carcinoma antigen values above the cutoff. Serum CEA and squamous cell carcinoma antigen values did not seem to correlate with stage or degree of differentiation of the tumours. CONCLUSIONS--The findings suggest that CEA is a good general marker for carcinoma, particularly adenocarcinoma. In contrast, squamous cell carcinoma antigen is more specific for squamous carcinoma. 相似文献
32.
Retroviral resistance mediated by the murine Fv1 gene is believed to result from a direct interaction between the Fv1 gene product and the viral capsid protein. To study the mechanism of Fv1 action, the expression and intracellular localisation of the Fv1 protein were examined. Only very low levels of protein expression seem necessary for virus restriction but the site of expression appears crucial. Active Fv1 was found in association with tubules of the trans-Golgi network, whereas an inactive form was localised in the endoplasmic reticulum. We hypothesize that Fv1 is compartmentalised in the cell on the pathway taken by virus en route to the nucleus, suggesting that incoming virus must pass the trans-Golgi network during its transit to the nucleus. 相似文献
33.
M. Willems L. Sheng T. Roskams B. Ramdani J. M. Doutrelepont F. Nevens P. Durez S. Treille M. Adler V. Desmet J. Fevery S. H. Yap 《Journal of medical virology》1994,44(3):266-271
Recently, evidence has been presented for a possible association between hepatitis C virus (HCV) infection and essential mixed cryoglobulinemia (EMC). Eleven consecutive patients with EMC and two with cryoglobulinemia type I were examined for the presence of markers of HCV infection. Eleven of 13 patients (10 with EMC and 1 with type I cryoglobulinemia) had anti-HCV antibodies (as determined by a second generation anti-HCV assay) and HCV-RNA in plasma or serum. HCV-RNA was also detected in liver biopsies of five patients. Genotyping showed that HCV genotype 1 was found in 10 of 11 patients with HCV-RNA (9 genotype 1b and 1 genotype 1a) and only one patient had HCV genotype 2. However, a similar high prevalence of genotype 1b (100%) was found in a group of 14 consecutive patients with chronic hepatitis C, who had no clinical evidence of cryoglobulinemia. Concomitant infection was present in three patients with genotypes 2, 3 and 4, respectively. These findings stress the high prevalence of HCV infection in patients with EMC and further study shows that a difference in genotype prevalence was not found between HCV-related EMC and chronic hepatitis C without clinical manifestations of EMC. © 1994 Wiley-Liss, Inc. 相似文献
34.
Kim CK Kim SW Park CS Kim BI Kang H Koh YY 《The Journal of allergy and clinical immunology》2003,112(1):64-71
BACKGROUND: The pathogenetic basis for the relationship between acute bronchiolitis and asthma has not yet been completely elucidated. OBJECTIVE: The aim of this study was to compare these 2 diseases in terms of their patterns of airway cytokine response (T(H)1 or T(H)2). METHODS: By using a bronchoalveolar lavage (BAL) technique, this study investigated the cytokine levels of BAL fluid in children with acute asthma who had no identifiable respiratory syncytial virus (RSV) infection (n = 18) and in infants with acute bronchiolitis caused by RSV (n = 22). Comparisons were made with normal control subjects (n = 14). IFN-gamma (T(H)1) and IL-4 and IL-5 (T(H)2) levels were measured in concentrated BAL fluids by means of ELISA. RESULTS: The IL-5 level (P <.001) and IL-5/IFN-gamma ratio (P <.001) were significantly increased in the asthmatic group with no identifiable RSV infection and in the RSV-induced bronchiolitis group compared with values in the control group. When infants in the bronchiolitis group were divided into eosinophil-positive and eosinophil-negative subgroups, the eosinophil-positive subgroup had significantly increased IL-5 levels (P <.001) and IL-5/IFN-gamma ratios (P <.01) compared with those in the control group, but similar cytokine responses were not induced in the eosinophil-negative subgroup. The percentage of BAL eosinophils correlated significantly with levels of BAL IL-5 in both the asthma group (r = 0.80, P =.000) and the bronchiolitis group (r = 0.82, P =.000). CONCLUSIONS: These findings suggest that a subgroup of the RSV-induced bronchiolitis group results in a T(H)2-type response, and this could provide a valuable framework to explain the link between RSV-induced bronchiolitis and asthma. 相似文献
35.
Tan JA George E Tan KL Chow T Tan PC Hassan J Chia P Subramanium R Chandran R Yap SF 《Clinical and experimental medicine》2004,4(3):142-147
Abstract
β-thalassemia is the most-common genetic disorder of hemoglobin synthesis in Malaysia, and about 4.5% of the population are
heterozygous carriers of the disorder. Prenatal diagnosis was performed for 96 couples using the Amplification Refractory
Mutation System and Gap-Polymerase Chain Reaction. We identified 17 β-globin defects-initiation codon for translation (T-G),
-29 (A-G), -28 (A-G), CAP +1 (A-C), CD 8/9 (+G), CD 15 (G-A), CD 17 (A-T), CD 19 (A-G), Hb E (G-A), IVS1-1 (G-T), IVS1-5 (G-C),
CD 41/42 (-CTTT), CD 71–72 (+A), IVS2-654 (CT), poly A(A-G), 100-kb Gγ(Aγδβ)° and 45-kb Filipino deletions. The 192 β-alleles studied comprised Chinese (151 patients), Malay (21), Orang Asli from
East Malaysia (15), Filipino (1), Indian (1), Indonesian Chinese (2), and Thai (1). In the Chinese, 2 β-globin defects at
CD 41/42 and IVS2-654 were responsible for 74% of β-thalassemia. β-mutations at CD 19, IVS1-1 (G-T), IVS1-5, poly A, and hemoglobin
E caused 76% of the hemoglobin disorders in the Malays. The Filipino 45-kb deletion caused 73.3% of bthalassemia in the Orang
Asli. Using genomic sequencing, the rare Chinese β-mutation at CD 43 (G-T) was confirmed in 2 Chinese, and the Mediterranean
mutation IVS1-1 (G-A) was observed in a Malay β-thalassemia carrier. The β-globin mutations confirmed in this prenatal diagnosis
study were heterogenous and 65 (68%) couples showed a different globin defect from each other. The use of specific molecular
protocols has allowed rapid and successful prenatal diagnosis of β-thalassemia in Malaysia. 相似文献
36.
A. P. Kiyasov A. A. Gumerova S. V. Petrov S. H. Yap 《Bulletin of experimental biology and medicine》1998,126(1):748-750
Isolated human hepatocytes cultured in liver biomatrix express cytokeratins 8 and 18. By the end of the first and during the
second week in culture, hepatocytes, express these cytokeratins and react with antibodies to cytokeratin-19. Cytokeratin-7
was found in individual cholangiocytes contaminating the culture. The presence of cytokeratin-19 in hepatocytes during the
second week of culturing can be regarded as its reexpression.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 7, pp. 118–120, July, 1998 相似文献
37.
Yap KL 《The Malaysian journal of pathology》1994,16(1):49-56
The aim of this study was to optimize the conditions for the passive adsorption of polyclonal antibody onto plain surface polystyrene latex particles and its performance in a slide latex agglutination test for rotavirus antigen detection. Cleaning of latex particles by washing through repetitive centrifuging, decanting and resuspending in distilled water was adequate in removing surfactants from the particles' surfaces to enable coating. A study of antibody concentration, incubation temperature and buffer pH revealed that optimum coating was achieved with a 3-fold excess of antibody to the calculated total particle surface capacity for the antibody in a glycine-saline buffer of pH 9.2 at 40 degrees C for 4 hours. The ionic strength and pH of the latex suspending buffer and the sample buffer were critical factors determining the sensitivity of the test and the appearance of non-specific agglutination. Ultrasonication, addition of glycerol and Tween 20, either individually or in combination, were able to suppress non-specific agglutination in some batches of latex reagents. Polyethylene glycol 6000 enhanced the quality of agglutination as well as reduced the time of its appearance, especially in reagents that produced poor agglutination. 相似文献
38.
39.
Summary. The origin of severe acute respiratory syndrome-associated corona-virus (SARS-CoV) is still a matter of speculation, although more than one year has passed since the onset of the SARS outbreak. In this study, we implemented a 3-step strategy to test the intriguing hypothesis that SARS-CoV might have been derived from a recombinant virus. First, we blasted the whole SARS-CoV genome against a virus database to search viruses of interest. Second, we employed 7 recombination detection techniques well documented in successfully detecting recombination events to explore the presence of recombination in SARS-CoV genome. Finally, we conducted phylogenetic analyses to further explore whether recombination has indeed occurred in the course of coronaviruses history predating the emergence of SARS-CoV. Surprisingly, we found that 7 putative recombination regions, located in Replicase 1ab and Spike protein, exist between SARS-CoV and other 6 coronaviruses: porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), bovine coronavirus (BCoV), human coronavirus 229E (HCoV), murine hepatitis virus (MHV), and avian infectious bronchitis virus (IBV). Thus, our analyses substantiate the presence of recombination events in history that led to the SARS-CoV genome. Like the other coronaviruses used in the analysis, SARS-CoV is also a mosaic structure. 相似文献
40.