全文获取类型
收费全文 | 830篇 |
免费 | 51篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 30篇 |
妇产科学 | 18篇 |
基础医学 | 125篇 |
口腔科学 | 19篇 |
临床医学 | 115篇 |
内科学 | 146篇 |
皮肤病学 | 10篇 |
神经病学 | 103篇 |
特种医学 | 36篇 |
外科学 | 80篇 |
综合类 | 3篇 |
预防医学 | 64篇 |
眼科学 | 20篇 |
药学 | 83篇 |
中国医学 | 6篇 |
肿瘤学 | 18篇 |
出版年
2023年 | 8篇 |
2022年 | 9篇 |
2021年 | 18篇 |
2020年 | 24篇 |
2019年 | 14篇 |
2018年 | 35篇 |
2017年 | 23篇 |
2016年 | 24篇 |
2015年 | 24篇 |
2014年 | 31篇 |
2013年 | 41篇 |
2012年 | 53篇 |
2011年 | 49篇 |
2010年 | 29篇 |
2009年 | 25篇 |
2008年 | 39篇 |
2007年 | 61篇 |
2006年 | 50篇 |
2005年 | 35篇 |
2004年 | 49篇 |
2003年 | 28篇 |
2002年 | 28篇 |
2001年 | 19篇 |
2000年 | 18篇 |
1999年 | 17篇 |
1998年 | 9篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 10篇 |
1991年 | 11篇 |
1990年 | 6篇 |
1989年 | 4篇 |
1988年 | 9篇 |
1987年 | 13篇 |
1986年 | 4篇 |
1985年 | 6篇 |
1984年 | 7篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1980年 | 4篇 |
1979年 | 6篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1974年 | 6篇 |
1973年 | 2篇 |
1966年 | 2篇 |
1965年 | 1篇 |
排序方式: 共有881条查询结果,搜索用时 15 毫秒
1.
S Flor D Guay J Opsahl K Tack G Matzke 《International journal of clinical pharmacology research》1991,11(3):115-121
The pharmacokinetics of the new fluoroquinolone antimicrobial ofloxacin were studied in 18 subjects with normal renal function or varying degrees of renal impairment, including patients undergoing continuous ambulatory peritoneal dialysis (CAPD) and haemodialysis. Apparent total body and renal clearances declined and elimination half-life increased with decreasing creatinine clearance. CAPD and haemodialysis removed clinically insignificant fractions of ofloxacin body burden over the study period (6-15% and 9-11% of the dose, respectively). The apparent volume of distribution, peak concentration, time to peak concentration, and non-renal clearance were not altered significantly by renal insufficiency. An extended dosing interval of 24-48 h is recommended, depending upon the degree of renal impairment, when creatinine clearance falls below 50 mL/min. In addition, supplemental doses would not appear to be necessary during CAPD and following haemodialysis. 相似文献
2.
3.
Telma T Florêncio Haroldo S Ferreira Jairo C Cavalcante Gabriela R Stux Ana L Sawaya 《European journal of cardiovascular prevention and rehabilitation》2007,14(2):346-348
OBJECTIVE: To test the hypothesis that short stature is associated with abdominal obesity, insulin resistance and lipid profile changes. METHODS: Anthropometric data were collected from 237 women (18-60 years old), residents of a shantytown in Maceió. Biochemical profiles of 60 individuals drawn from this population were determined. RESULTS: Total and low-density lipoprotein (LDL) cholesterol levels and insulin resistance rose with increasing waist : hip circumference ratio, particularly in women. Short, overweight individuals exhibited larger biochemical alterations than overweight individuals of average stature. CONCLUSION: Short stature, when associated with overweight, is a risk factor for increased insulin resistance and alterations in lipid profile. 相似文献
4.
5.
Clade analysis and surface antigen polymorphism of hepatitis B virus American genotypes 总被引:4,自引:0,他引:4
Eight genotypes (A-H) of hepatitis B virus (HBV) have been described, HBV genotypes F and H being autochthonous to America. HBV genotype F has been classified in four clusters. The objective of this study was to gain insight into the molecular epidemiology of HBV American genotypes, as well as to analyze the genotype-related polymorphism in some functional domains of the surface proteins. The sequences of the S region of 106 isolates genotype F and H were analyzed, out of which 47 isolates genotype F circulated in different Venezuelan populations. Most of the Venezuelan isolates genotype F were grouped in cluster III (n = 39) and 7 in cluster II. One isolate obtained from a blood donor could not be classified in any clade and harbored amino acid substitutions characteristic of a vaccine escape mutant (G145R) and a stop codon in the surface antigen. Amino acid analysis of the PreS and S gene products showed unique genetic characteristics in genotype F and H sequences in some important domains involved in the early steps of infection. Out of 30 available sequences, two complete genome sequences of HBV genotype F from Venezuela were obtained. Phylogenetic analysis of these complete genomes confirmed the presence of four clusters inside genotype F, differing in more than 4% nucleotide divergence. Our extended analysis showed that genotype F clades Ia, III, and IV exhibit a restricted geographic distribution (Central America, the North and the South of South America, respectively) while clades Ib and II are found in all the Americas except in the Northern South America and North America respectively. 相似文献
6.
Amygdala-prefrontal coupling depends on a genetic variation of the serotonin transporter 总被引:12,自引:0,他引:12
Heinz A Braus DF Smolka MN Wrase J Puls I Hermann D Klein S Grüsser SM Flor H Schumann G Mann K Büchel C 《Nature neuroscience》2005,8(1):20-21
Major depression is conditionally linked to a polymorphism of the human serotonin transporter gene (SLC6A4). During the presentation of aversive, but not pleasant, pictures, healthy carriers of the SLC6A4 short (s) allele showed stronger activation of the amygdala on functional magnetic resonance imaging. s carriers also showed greater coupling between the amygdala and the ventromedial prefrontal cortex, which may contribute to the abnormally high activity in the amygdala and medial prefrontal cortex seen in major depression. 相似文献
7.
Localization of Somatosensory Evoked Potentials in Primary Somatosensory Cortex: A Comparison Between PCA and MUSIC 总被引:1,自引:0,他引:1
The aim of this study was to test source modeling strategies for EEC-data from a clinical group of amputees. The experimental conditions (measuring time, age and condition of the patients) resulted in low quality EEC-data. Noise reduction was achieved by a principal component analysis (PCA) and a multiple signal classification (MUSIC). A comparison of the results of these two methods with traditional signal handling yielded superior results for the MUSIC algorithm. 相似文献
8.
Molecular and serological evaluation of surface antigen negative hepatitis B virus infection in blood donors from Venezuela 总被引:2,自引:0,他引:2
Gutiérrez C Devesa M Loureiro CL León G Liprandi F Pujol FH 《Journal of medical virology》2004,73(2):200-207
Surface antigen negative hepatitis B virus (HBV) infection was evaluated in Venezuela, by molecular characterization of blood samples positive for antibodies to core antigen (anti-HBc) and negative for surface antigen (HBsAg) in blood donors (residual infections). HBV DNA was found in 11/258 samples (4.3%), and was significantly associated with high levels of anti-HBc antibodies (>25 UI/ml, P < 0.05), while no correlation was found between the presence of HBV DNA and the levels of anti-HBs. Synonymous and non-synonymous mutations were found in the HBV surface region (but not vaccine escape mutants) and in the precore/core region (precore mutants in 2/7 samples and 33-45 bp deletions near the N-terminal core region in 4/19 samples). While HBV genotype F prevails among HBsAg positive samples from blood donors in Venezuela, residual infection isolates were mainly genotypes A and D. Phylogenetic analysis of viral surface and core region revealed discrepancies in genotype designation in 6/9 samples, suggesting the presence of mixed infection or recombination. In conclusion, HBV residual infection in Venezuela does not seem to be frequently observed in HBV genotype F. This type of infection is frequently associated with variants exhibiting mutations in the surface gene that might be affecting the correct recognition by commercial tests, with precore mutants and with core internal deletions. These variants do not seem to cause severe liver disease, and on the contrary, were found circulating at low viremia. 相似文献
9.
N. Matamoros Florí J. Mila Llambi T. Español Boren S. Raga Borja G. Fontan Casariego 《Journal of clinical immunology》1997,17(4):333-339
The Spanish Registry for Primary Immunodeficiency Diseases (REDIP) was organized in 1993. One thousand sixty-nine cases of primary immunodeficiency diseases (PID) were registered in patients diagnosed between January 1980 and December 1995. PID diagnosis was made according to the World Health Organization criteria. The most frequent disorders were IgA deficiency (n = 394) and common variable immunodeficiency (n = 213), followed by severe combined immunodeficiency (n = 61), C1 inhibitor deficiency (n = 52), X-Iinked agammaglobulinemia (n = 49), IgG subclass deficiency (n = 48), and chronic granulomatous disease (n = 32). A comparative study between REDIP and data recently obtained from the European registry (ESID Report, 1995) revealed important differences between phagocytic disorders and complement deficiencies reported in both registries, 4.9 vs 8.7 and 6.0 vs 3.6, while percentages of predominantly antibody deficiencies and T cell and combined deficiencies concurred with those reported in the European registry, 69.3 vs 64.7 and 14.7 vs 20.2, respectively. The heterogeneous nature of the geographical distribution of cases submitted may indicate underdiagnosis of PID in some country areas; surprisingly, the interval between the onset of clinical symptoms and diagnosis was significant, even in immunodeficiency diseases, such as IgA deficiency, which are easy to diagnose. 相似文献
10.
Bronchocentric granulomatosis: a complication of allergic bronchopulmonary aspergillosis. 总被引:1,自引:0,他引:1
G Hanson N Flor I Wells H Novey S Galant 《The Journal of allergy and clinical immunology》1977,59(1):83-90
Hypersensitivity to the fungal antigens of Aspergillus fumigatus may result in a spectrum of immune injury collectively known as allergic bronchopulmonary aspergillosis (ABPA). This report describes a 14-yr-old boy who presented clinical findings consistent with ABPA,including a history of asthma, blood eosinophilia, serum precipitins, and IgE antibodies to Aspergillus fumigatus. Sputum Aspergillus, pulmonary infiltrates, and dual types I and III skin reactions to Aspergillus fumigatus were observed also. Pathology of the resected right upper lobe revealed severe bronchial destruction with the findings of bronchocentric granulomatosis. Noninvasive septate fungal hyphae compatible with Aspergillus were identified. Cultures from sputum and surgical specimens grew Aspergillus and Mycobacterium intracellulare avium. The PPD-B (purified protein derivative-Batty) intradermal skin test produced a 6 mm induration (PPD-S was negative). The patient's condition has been well controlled with prednisone and several antituberculous drugs. In addition, inflammatory and immunologic parameters have begun to return to normal. The relationship between ABa and the atypical mycobacterial infection is not clear. The association of ABPA with the severe bronchial destruction seen in bronchocentric granulomatosis is emphasized to alert physicans to this serious sequelae of ABa seen in the asthmatic. 相似文献