全文获取类型
收费全文 | 1071篇 |
免费 | 74篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 32篇 |
妇产科学 | 20篇 |
基础医学 | 132篇 |
口腔科学 | 12篇 |
临床医学 | 130篇 |
内科学 | 208篇 |
皮肤病学 | 26篇 |
神经病学 | 49篇 |
特种医学 | 110篇 |
外科学 | 127篇 |
综合类 | 28篇 |
预防医学 | 126篇 |
眼科学 | 10篇 |
药学 | 76篇 |
中国医学 | 1篇 |
肿瘤学 | 60篇 |
出版年
2023年 | 7篇 |
2022年 | 8篇 |
2021年 | 36篇 |
2020年 | 11篇 |
2019年 | 24篇 |
2018年 | 33篇 |
2017年 | 25篇 |
2016年 | 22篇 |
2015年 | 29篇 |
2014年 | 51篇 |
2013年 | 77篇 |
2012年 | 47篇 |
2011年 | 53篇 |
2010年 | 63篇 |
2009年 | 46篇 |
2008年 | 48篇 |
2007年 | 52篇 |
2006年 | 42篇 |
2005年 | 41篇 |
2004年 | 25篇 |
2003年 | 22篇 |
2002年 | 23篇 |
2001年 | 17篇 |
2000年 | 11篇 |
1999年 | 17篇 |
1998年 | 29篇 |
1997年 | 33篇 |
1996年 | 31篇 |
1995年 | 17篇 |
1994年 | 21篇 |
1993年 | 13篇 |
1992年 | 11篇 |
1991年 | 13篇 |
1990年 | 14篇 |
1989年 | 14篇 |
1988年 | 8篇 |
1987年 | 10篇 |
1986年 | 11篇 |
1985年 | 10篇 |
1984年 | 12篇 |
1983年 | 6篇 |
1982年 | 14篇 |
1981年 | 9篇 |
1980年 | 11篇 |
1979年 | 6篇 |
1978年 | 6篇 |
1977年 | 8篇 |
1976年 | 7篇 |
1975年 | 6篇 |
1973年 | 4篇 |
排序方式: 共有1158条查询结果,搜索用时 15 毫秒
11.
12.
Life expectancy in British Marfan syndrome populations 总被引:2,自引:0,他引:2
JR Gray AB Bridges RR West L. McLeish AG Stuart JCS Dean MEM Porteous M. Boxer SJ Davies 《Clinical genetics》1998,54(2):124-128
A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970–1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3 ± 16.5 years. 50% median cumulative survival in the total cohort (n = 206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome. 相似文献
13.
Arbour NC; Zlotogora J; Knowlton RG; Merin S; Rosenmann A; Kanis AB; Rokhlina T; Stone EM; Sheffield VC 《Human molecular genetics》1997,6(5):689-694
Achromatopsia is an autosomal recessive disease of the retina,
characterized clinically by an inability to distinguish colors, impaired
visual acuity, nystagmus and photophobia. A genome-wide search for linkage
was performed using an inbred Jewish kindred from Iran. To facilitate the
genome-wide search, we utilized a DNA pooling strategy which takes
advantage of the likelihood that the disease in this inbred kindred is
inherited by all affected individuals from a common founder. Equal molar
amounts of DNA from all affected individuals were pooled and used as the
PCR template for short tandem repeat polymorphic markers (STRPs). Pooled
DNA from unaffected members of the kindred was used as a control. A
reduction in the number of alleles in the affected versus control pool was
observed at several loci. Upon genotyping of individual family members,
significant linkage was established between the disease phenotype and
markers localized on chromosome 2. The highest LOD score observed was 5.4
(theta = 0). When four additional small unrelated families were genotyped,
the combined peak LOD score was 8.2. Analysis of recombinant chromosomes
revealed that the disease gene lies within a 30 cM interval which spans the
centromere. Additional fine-mapping studies identified a region of
homozygosity in all affected individuals, narrowing the region to 14 cM. A
candidate gene for achromatopsia was excluded from this disease interval by
radiation hybrid mapping. Linkage of achromatopsia to chromosome 2 is an
essential first step in the identification of the disease-causing gene.
相似文献
14.
15.
There are compelling molecular and epidemiological data which indicate that infection with certain genital human papillomaviruses (HPVs), such as HPV 16 and HPV 18, has a critical role in initial changes that lead to cervical and probably other anogenital cancers. These observations prompted us to investigate the prevalence of cervical infection with genital human papillomaviruses in Tunisia. We used the polymerase chain reaction (PCR) to detect and type HPV DNA. The prevalence of HPV infection in a population of 106 Tunisian women recruited at the Offices Nationaux de la Famille et de Population (ONFP) was 13.6%. Molecular HPV typing indicated a high prevalence of HPV at high oncogenic risk; Our results indicate that the infection with genital human papillomaviruses is frequent in the Tunisian population. 相似文献
16.
A. Hammami G. Arlet S. Ben Redjeb F. Grimont A. Ben Hassen A. Rekik A. Philippon 《European journal of clinical microbiology & infectious diseases》1991,10(8):641-646
In a Tunisian hospital 27 babies, including 12 who were premature, in a single intensive care unit suffered acute gastroenteritis in the period from January to May 1988. The mean age at the onset of gastroenteritis was 8.4 days; nine babies died.Salmonella wien was isolated from stools (all babies) and blood (4 babies). It was also isolated from the stools of one nurse and from a mattress. Twelve of the babies had received cefotaxime, which was successfully replaced by oral colimycin. The outbreak was stopped by the implementation of infection control measures. All isolates ofSalmonella wien were of the same biotype, and had the same antibiotic resistance pattern (third generation cephalosporins, monobactams, aminoglycosides, chloramphenicol, trimethoprim and sulphonamides) and plasmid DNA restriction pattern. The isolates were all susceptible to a combination of cefotaxime and clavulanic acid (a -lactamase inhibitor), which displayed synergy, suggesting the presence of a -lactamase (geometric mean MICs 11.24 µg/ml for cefotaxime alone and 0.24 µg/ml in combination with 0.1 µg/ml potassium clavulanate). All isolates produced TEM-1 and SHV-2 -lactamase which was not transferable toEscherichia coli by conjugation. The presence of the SHV-2 enzyme inSalmonella wien may allow it to adapt to newer -lactams which is a cause for concern in this hospital. 相似文献
17.
Assessment of the mutagenicity of dichloroacetic acid in lacI transgenic B6C3F1 mouse liver 总被引:2,自引:0,他引:2
Dichloroacetic acid (DCA) is a chlorination byproduct found in finished
drinking water. When administered in drinking water this chemical has been
shown to produce hepatocellular adenomas and carcinomas in B6C3F1 mice over
the animal's lifetime. In this study, we investigated whether mutant
frequencies were increased in mouse liver using treatment protocols that
yielded significant tumor induction. DCA was administered continuously at
either 1.0 or 3.5 g/l in drinking water to male transgenic B6C3F1 mice
harboring the bacterial lacI gene. Groups of five or six animals were
killed at 4, 10 or 60 weeks and livers removed. At both 4 and 10 weeks of
treatment, there was no significant difference in mutant frequency between
the treated and control animals at either dose level. At 60 weeks, mice
treated with 1.0 g/l DCA showed a 1.3-fold increase in mutant frequency
over concurrent controls (P = 0.05). Mice treated with 3.5 g/l DCA for 60
weeks had a 2.3-fold increase in mutant frequency over the concurrent
controls (P = 0.002). The mutation spectrum recovered from mice treated
with 3.5 g/l DCA for 60 weeks contained G:C-->A:T transitions (32.79%)
and G:C-->T:A transversions (21.31%). In contrast, G:C-->A:T
transitions comprised 53.19% of the recovered mutants among control
animals. Although only 19.15% of mutations among the controls were at T:A
sites, 32.79% of the mutations from DCA-treated animals were at T:A sites.
This is consistent with the previous observation that the proportion of
mutations at T:A sites in codon 61 of the H-ras gene was increased in
DCA-induced liver tumors in B6C3F1 mice. The present study demonstrates
DCA-associated mutagenicity in the mouse liver under conditions in which
DCA produces hepatic tumors.
相似文献
18.
Female sterilisation is an important component of National Family Welfare Programme. The target group is best motivated during the puerperium for such a procedure. However laparoscopic sterilisation which has got some distinct advantages, is not technically feasible at this time. The authors have used a technique where the advantages of cosmetic appearance, reduced post operative morbidity and reversibility can be conferred on the puerperal women.After trying out the method individually in some cases, a formal case control study design has been made and an evaluation study has been performed in 122 cases. The technique has been found to be cosmetically more acceptable, both at clientele and peer evaluation levels (p<0.001). Though all the four parameters of post operative morbidity have shown better results for the technique evaluated as against the conventional technique, statistical significance has been achieved in two of the parameters (p<0.05).KEY WORDS: Cosmetics, Female sterilisation, Post operative morbidity 相似文献
19.
Hossein Kalantari Rajnish Jaiswal Isaac Bruck Hussein Matari Farzaneh Ghobadi Jeremy Weedon Getaw Worku Hassen 《The American journal of emergency medicine》2013,31(11):1595-1597
BackgroundTraditionally, intracranial pressure is measured by direct ventriculostomy, which is invasive. Noninvasive measures such as bedside ultrasound and magnetic resonance imaging have been advocated and utilized recently to assess the intracranial pressure. The role of this study is to determine the degree of agreement between measurements of the optic nerve sheath diameter by computed tomography (CT) and magnetic resonance imaging (MRI).Materials and MethodsRetrospective chart review of 100 consecutive patients who had both MRI and CT scan of the head from January 1, 2011, until March 31, 2013, at our center was performed. A discrepancy of 0.2 mm between the 2 measurements was set as acceptable difference. The measurements of optic nerve sheath diameter (ONSD) were compared for agreement between the 2 modalities using the method by Bland and Altman.ResultsA total of 100 patients with both MRI and CT scan of the head were selected. Of these 100 patients, 24 were male and 76 were female. The average age was 63 years. No ONSD abnormality was detected in any of the patients. The discrepancy in measurements of the ONSD between CT and MRI in transverse plane was less than the predetermined cut-off value of 0.2 mm. Within-subject variance was estimated at 0.0058 for both CT and MRI.ConclusionComparable results without significant discrepancy as predetermined by the study groups were obtained from CT scan. Measurement of ONSD by CT scan can be used to indirectly asses the intracranial pressure in addition to clinical assessment and other signs of increased intracranial pressure on CT scan. 相似文献
20.
Arij Mechergui Wafa Achour Assia Ben Hassen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2014,122(5):437-442
In the present work, nearly the entire 16S rRNA gene sequences of 46 clinical samples of Neisseria spp. were determined, and the aligned sequences were analyzed to investigate the diversity of 16S rRNA genes in each commensal Neisseria species. Two 16S rRNA types were identified in two Neisseria sicca strains, three 16S rRNA types in five Neisseria macacae strains, fourteen 16S rRNA types in twenty Neisseria flavescens isolates, and fourteen 16S rRNA types in nineteen Neisseria mucosa isolates. The number of nucleotides that were different between 16S rRNA sequences within specie ranged from 1 to 15. We found high intraspecific sequence variation in 16S rRNA genes of Neisseria spp. strains. 相似文献