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排序方式: 共有682条查询结果,搜索用时 15 毫秒
1.
山东省部分地区献血员丙型肝炎病毒感染状况及分型研究   总被引:2,自引:0,他引:2  
选择424例有偿献血员用ELISA检测抗-HCV,对抗-HCV阳性血清用ELISA进行血清学分型,对己确定血清型者采用RT-PCR作基因分型.结果424例献血员中,HCV感染率为21.70%(92/424),献全血并血浆者的HCV感染率(45.14%)显着高于只献全血者(6.94%);92例抗-HCV阳性者中,血清学分型率为34.78%(32份),其中血清学Ⅰ型30例(93.75%)、Ⅱ型2例(6.25%):该32例血清中有30例可用基因分型,其中基因Ⅱ型26例(86.67%)、Ⅲ型3例(10%)、Ⅱ/Ⅲ型混合感染1例(3.33%),两种分型方法的一致率为93.33%(28/30).表明山东省部分地区献血人群的HCV感染率较高;献血浆是该献血人群HCV感染的危险因素;其HCV感染以血清学I型和基因Ⅱ型为主.  相似文献   
2.
BackgroundHigh-risk human papillomavirus (hrHPV) DNA positive women require triage testing to identify those with high-grade cervical intraepithelial neoplasia or cancer (≥CIN2).ObjectiveComparing three triage algorithms (1) E7 mRNA testing following HPV16/18/31/33/45/52/58 genotyping (E7 mRNA test), (2) HPV16/18 DNA genotyping and (3) cytology, for ≥CIN2 detection in hrHPV DNA-positive women.Study designhrHPV DNA-positive women aged 18–63 years visiting gynecology outpatient clinics were included in a prospective observational cohort study. From these women a cervical scrape and colposcopy-directed biopsies were obtained. Cervical scrapes were evaluated by cytology, HPV DNA genotyping by bead-based multiplex genotyping of GP5+6+-PCR-products, and presence of HPV16/18/31/33/45/52/58 E7 mRNA using nucleic acid sequence-based amplification (NASBA) in DNA positive women for respective HPV types. Sensitivities and specificities for ≥CIN2 were compared between E7 mRNA test and HPV16/18 DNA genotyping in the total group (n = 348), and E7 mRNA test and cytology in a subgroup of women referred for non-cervix-related gynecological complaints (n = 133).ResultsSensitivity for ≥CIN2 of the E7 mRNA test was slightly higher than that of HPV16/18 DNA genotyping (66.9% versus 60.9%; ratio 1.10, 95% CI: 1.0002–1.21), at similar specificity (54.8% versus 52.3%; ratio 1.05, 95% CI: 0.93–1.18). Neither sensitivity nor specificity of the E7 mRNA test differed significantly from that of cytology (sensitivity: 68.8% versus 75.0%; ratio 0.92, 95% CI: 0.72–1.17; specificity: 59.4% versus 65.3%; ratio 0.91, 95% CI: 0.75–1.10).ConclusionFor detection of ≥CIN2 in hrHPV DNA-positive women, an algorithm including E7 mRNA testing following HPV16/18/31/33/45/52/58 DNA genotyping performs similar to HPV16/18 DNA genotyping or cytology.  相似文献   
3.
快速盐析法提取DNA在HLA基因分型中的应用   总被引:28,自引:4,他引:28  
采用快速盐析方法提取人类有核细胞DSA,并在临床肾移植的HLA基因配型中应用。通过对210份不同组织来源的样本与标准酚氯仿法同步对比研究显示:快速盐析法提取模板DNA,无污染和有害作用;操作简单、快速,总耗时110分钟;方法稳定可靠,无一例失败;所获DNA质量好,纯度高,达到酚氯仿法所获DNA的水平;用于临床肾移植基因型均获成功,与酚氯仿法结果完全相同。证实该法提取的DNA适用于临床器官移植基因水  相似文献   
4.
ObjectiveThe objective of this study was to review our experience with abdominal radical trachelectomy in patients with early-stage cervical cancer.MethodsWe performed a retrospective review of all patients who underwent an abdominal radical trachelectomy at the Instituto de Cancerologia—Clinica las Americas in Medellin, Colombia, between April 2002 and January 2008. Data collected included age, stage, histopathologic subtype, tumor size, evidence of lymph-vascular space invasion, estimated blood loss, number of perioperative blood transfusions, number and disease status of lymph nodes removed, disease status of surgical specimen, length of hospital stay, intraoperative and postoperative complications, follow-up time, and fertility outcomes.ResultsFifteen patients underwent an abdominal radical trachelectomy during the study period. The median patient age was 30 years (range, 25–38). Three patients had stage IA2 and 12 had stage IB1 cervical cancer. Eleven patients had squamous cell carcinoma and 4 had adenocarcinoma. Thirteen patients were diagnosed by cervical conization and 2 by colposcopically directed biopsy. All patients had tumors smaller than 2 cm. The median estimated blood loss was 400 ml (range, 200–1000). The median surgical time was 265 min (range, 210–330). The median number of units of packed red blood cells transfused per patient was 2. The median number of lymph nodes removed was 26 (range, 11–48). The median length of hospitalization was 3 days (range, 2–7). The median follow-up time was 32 months (range, 5–32). There was 1 intraoperative complication and 6 postoperative complications in 4 patients. No patient has had a recurrence. Three patients were able to conceive spontaneously; 1 delivered at 31 weeks' gestation, and 2 delivered at term.ConclusionAbdominal radical trachelectomy is feasible and can be performed safely in a developing country in well-selected patients with early cervical cancer who wish to preserve their fertility.  相似文献   
5.

AIMS:

The aim of this study was to evaluate the frequencies of the HLA genotypes DQ2 and DQ8 and the alleles A1*05, A1*0201, B1*0201 and B1*0302 in individuals with celiac disease in Recife, northeastern Brazil.

METHODS:

HLA DQ2 and DQ8 genotyping was performed for 73 individuals with celiac disease and 126 first-degree relatives with negative transglutaminase serology. The alleles DQA1*05, DQA1*0201, DQB1*02 and DQB1*0302 were identified by sequencing using specific primers and the EU-DQ kit from the Eurospital Laboratory, Trieste, Italy and double-checked by the All Set SPP kit (Dynal).

RESULTS:

Among the 73 cases, 50 (68.5%) had the genotype DQ2, 13 (17.8%) had DQ8, 5 (6.8%) had DQ2 and DQ8, and 5 did not have any of these genotypes. Among the 5 negative individuals, four had the B1*02 allele and one did not have any of the alleles studied. B1*02 was the most frequent allele in both groups (94% in the patients and 89% in the control relatives).

CONCLUSIONS:

In this study, celiac disease was associated with the genotypes DQ2 and DQ8. DQ2 predominated, but the distribution of the frequencies was different from what has been found in European populations and was closer to what has been found in the Americas. The high frequencies of the HLA genotypes DQ2 and DQ8 that were found in first-degree relatives would make it difficult to use these HLA genotypes for routine diagnosis of celiac disease in this group.  相似文献   
6.

Background

Our ability to detect single nucleotide polymorphisms (SNPs) and gene mutations has become commonplace in the clinical laboratory setting. Molecular genetic testing for gene variants associated with hypercoagulability has become a standard of practice for Factor V and Factor II polymorphisms.

Methods

In this study, we evaluated a novel technology that allows for the routine assessment of these SNPs, the Verigene® System (Nanosphere Inc, Northbrook, IL), as a low-density array that does not require PCR amplification prior to detection. Precision was assessed by using multiple operators for within and between run performance evaluations. Accuracy was assessed by evaluating 176 DNA samples from patients who had been previously tested for the SNPs of interest in this multicenter study.

Results

No mis-calls were made during the precision studies. Testing of the 176 DNA samples resulted in individual call rates for the F5, F2 and MTHFR genotypes of 98.3%, 94.9%, and 92.6%, respectively.

Conclusions

The Verigene®F5/F2/MTHFR Nucleic Acid Tests for the Factor V (1691G>A), Factor II (20210G>A) and MTHFR (677C>T) genes were robust methods for SNP detection without the need for DNA amplification. The ease of use and performance of this system makes it suitable for the clinical laboratory setting.  相似文献   
7.
Objective Human Lyme Borreliosis (LB), which is caused by Borrefia burgdorferi sensu lato (B. burgdorferi), has been identified as a major arthropod-borne infectious disease in China. We aimed to develop a multiple locus variable-number tandem repeat (VNTR) analysis (MLVA) assay for the genotyping of Borrelia burgdorJ:eri strains detected in China. Methods B. garinii PBi complete 904.246 kb chromosome and two plasmids (cp26 and Ip54) were screened by using Tandem Repeats Finder program for getting potential VNTR loci, the potential VNTR loci were analyzed and identified with PCR and the VNTR loci data were analyzed and MLVA clustering tree were constrcted by using the categorical coefficient and the unweighted pair-group method with arithmetic means (UPGMA). Results We identified 5 new VNTR loci through analyzing 47 potential VNTR loci. We used the MLVA protocol to analyse 101 B. burgdorferi strains detected in China and finally identified 51 unique genotypes in 4 major clusters including B. burgdorferi sensu stricto (B.b.s.s), B. garinii, B. a[zelii, and B. valaisiana, consistent with the current MLSA phylogeny studies. The allele numbers of VNTR-1, VNTR-2, VNTR-3, VNTR-4, and VNTR-5 were 7, 3, 9, 7, and 6. The Hunter-Gaston index (HGI) of five VNTR loci were 0.79, 0.22, 0.77, 0.71, and 0.67, respectively. The combined HGI of five VNTR loci was 0.96. Clustering of the strains of Xinjiang, Inner Mongolia and Heilongjiang was confirmed, and this situation was consistent with the close geographical distribution of those provinces. Conclusion The MLVA protocol esytablished in this study is easy and can show strains' phylogenetic relationships to distinguish the strains of Borrelia species. It is useful for further phylogenetic and epidemiological analyses of Borrelia strains.  相似文献   
8.
9.
[目的]从蜱标本中分离到3株Roseomonas(玫瑰单胞菌),了解其与国内及国外的Roseomonas(玫瑰单胞菌)分离株之间的基因型别关系。[方法]鉴于国内外还没有对Roseomonas(玫瑰单胞菌)基因分型的成型方法可以利用,采用了传统的基于16SrDNA的方法进行不同分离株的比较。[结果]3分离株XTD509、XTD510、XTD622在系统进化树中聚在同一簇内,且与美国分离株R.cervicalisATCC49957聚在一个小的分支内,同源性高达99.1%;与我国另2分离株JS018、TH-G33在系统进化树位于大的不同分支。[结论]该3分离株属于同一基因型,且可能与菌株R.cervicalisATCC49957为同一个种。  相似文献   
10.
Li Q  Li LY  Huang SW  Li L  Chen XW  Zhou WJ  Xu XM 《Clinical biochemistry》2008,41(9):681-687

Background

β-thalassemia represents a great heterogeneity as over 200 mutations have been identified for the β-globin gene responsible for this disease. A rapid genotyping test with high accuracy, selectivity, and reproducibility suitable for the determination of known mutations is needed for prenatal screening and post-natal diagnosis of this disease in clinical setting.

Design and methods

We have performed the validation of a DHPLC assay for direct genotyping of known causative mutations in β-globin gene using the chromatographic pattern-based strategy under partially-denaturing conditions.

Results

DHPLC assay was established based on the analysis of 795 DNA samples from a group of various genotypes for the 20 mutations and 8 polymorphisms in β-globin gene then validated on 319 tests in a blind study. The results obtained with this assay were in concordance with the results obtained by DNA sequence analysis.

Conclusion

This simple method can meet the requirements of direct genotyping of known β-thalassemia mutations and/or polymorphisms in the clinical setting for Chinese and in general as a model for other populations.  相似文献   
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