全文获取类型
收费全文 | 589篇 |
免费 | 58篇 |
国内免费 | 13篇 |
专业分类
儿科学 | 16篇 |
妇产科学 | 7篇 |
基础医学 | 136篇 |
口腔科学 | 8篇 |
临床医学 | 78篇 |
内科学 | 140篇 |
皮肤病学 | 9篇 |
神经病学 | 33篇 |
特种医学 | 86篇 |
外科学 | 33篇 |
综合类 | 2篇 |
预防医学 | 20篇 |
眼科学 | 3篇 |
药学 | 26篇 |
中国医学 | 1篇 |
肿瘤学 | 62篇 |
出版年
2022年 | 3篇 |
2021年 | 6篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 11篇 |
2014年 | 4篇 |
2013年 | 5篇 |
2012年 | 16篇 |
2011年 | 14篇 |
2010年 | 12篇 |
2009年 | 8篇 |
2008年 | 16篇 |
2007年 | 30篇 |
2006年 | 19篇 |
2005年 | 28篇 |
2004年 | 17篇 |
2003年 | 20篇 |
2002年 | 24篇 |
2001年 | 16篇 |
2000年 | 18篇 |
1999年 | 16篇 |
1998年 | 29篇 |
1997年 | 21篇 |
1996年 | 26篇 |
1995年 | 20篇 |
1994年 | 14篇 |
1993年 | 14篇 |
1992年 | 15篇 |
1991年 | 8篇 |
1990年 | 8篇 |
1989年 | 27篇 |
1988年 | 30篇 |
1987年 | 18篇 |
1986年 | 15篇 |
1985年 | 16篇 |
1984年 | 9篇 |
1983年 | 11篇 |
1982年 | 13篇 |
1981年 | 5篇 |
1980年 | 11篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1977年 | 11篇 |
1976年 | 7篇 |
1975年 | 7篇 |
1974年 | 2篇 |
1970年 | 2篇 |
1969年 | 3篇 |
1967年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有660条查询结果,搜索用时 31 毫秒
1.
目的快速鉴定血培养中的金黄色葡萄球菌和凝固酶阴性葡萄球菌(CoNS),结合临床快速判定是否为污染菌。方法采用荧光原位杂交法鉴定血培养中的金黄色葡萄球菌和CoNS,杂交结果若为CoNS,根据临床资料进行判断,并与文献推荐的污染判断法进行结果比较。结果探针的特异性经由标准菌株和临床分离菌株证实。金黄色葡萄球菌探针的特异性和敏感性均为100%,GoNS探针的特异性和敏感性分别为100%和95.5%。179株CoNS中117株判断为污染菌,污染率为68%,与文献推荐的污染判断方法一致。结论荧光原位杂交法适用于血培养中的金黄色葡萄球菌和CoNS的快速鉴定,以排除CoNS污染。 相似文献
2.
偏头痛大鼠脑内5-羟色胺1F和诱导型一氧化氮合酶基因的表达变化及针刺的干预效应 总被引:3,自引:0,他引:3
目的:前期实验已证实针刺治疗偏头痛疗效优越。观察针刺对偏头痛大鼠脑内5-羟色胺1F和诱导型一氧化氮合酶mRNA表达的调控作用。方法:实验于2005-11/2006-05在中南大学湘雅医院中西医结合研究所实验室完成。①选用SD大鼠40只,按随机数字表法分为4组(n=10),除正常对照组外,其余3组均复制大鼠偏头痛模型。模型对照组只造模,不作其他处理;针刺治疗组造模后进行针刺;针刺预防组针刺后造模电刺激20min。针刺方法:针刺大鼠双侧太冲、阳陵泉穴20min。采用疏密波,电流强度0.3~0.6mA,留针20min,1次/d,共5次。②实验完毕后取脑干及三叉神经节匀浆,采用反转录-聚合酶链反应法测定5-羟色胺1F和诱导型一氧化氮合酶mRNA表达。结果:进入结果分析正常对照组10只,模型对照组、针刺治疗组、针刺预防组各9只,共脱失3只。①与正常对照组比较,模型对照组大鼠诱导型一氧化氮合酶mRNA表达显著增强(P<0.01),5-羟色胺1FmRNA表达显著减弱(P<0.01)。②与模型对照组比较,针刺预防组和针刺治疗组诱导型一氧化氮合酶mRNA表达明显减弱(P<0.01),5-羟色胺1FmRNA表达显著增强(P<0.01)。结论:针刺调控5-羟色胺1F和诱导型一氧化氮合酶mRNA的表达可能是针刺防治偏头痛的分子机制。 相似文献
3.
Retrorenal colon: implications for percutaneous diskectomy 总被引:1,自引:0,他引:1
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary. 相似文献
4.
5.
6.
A cytogenetic study of 53 human gliomas 总被引:8,自引:1,他引:8
R B Jenkins D W Kimmel C A Moertel C G Schultz B W Scheithauer P J Kelly G W Dewald 《Cancer Genetics and Cytogenetics》1989,39(2):253-279
Cytogenetic studies were performed on human glioma samples obtained by stereotactic biopsy, stereotactic craniotomy, or routine craniotomy. Using in situ culture and robotic harvesting techniques, we obtained suitable metaphases in 50 (94%) of 53 tumors, including 28 diffuse astrocytomas, four juvenile pilocytic astrocytomas, two gliosarcomas, three other miscellaneous astrocytomas, eight oligodendrogliomas, four mixed oligodendroglioma-astrocytomas, and four ependymomas. Cytogenetic studies were performed only on primary cultures; the mean culture time was 9.6 days (range 1-31 days). One or more chromosomally abnormal clones were observed in 35 (66%) tumors. Eleven (21%) other specimens had random nonclonal chromosome abnormalities. In four (8%) specimens, no chromosome abnormalities were noted. The results of this study suggest that grade 3 and 4 tumors are more likely to contain an abnormal clone than tumors of grade 1 or 2 (p less than 0.01). The most common numeric chromosome abnormalities were -6, +7, -10, -13, -14, -15, -18, and -Y. The most common structural abnormalities involved 1p, 6q, 7q, 8p, 9p, 11p, 11q, 13q, and 19q. Four tumors had two or more independent clones and ten contained subclones demonstrating karyotype evolution. With in situ culture and robotic harvesting techniques, cytogenetic studies can be successful on nearly all human gliomas, including those derived from small stereotactic biopsies. 相似文献
7.
Female phenotype and multiple abnormalities in sibs with a Y chromosome and partial X chromosome duplication: H--Y antigen and Xg blood group findings. 总被引:4,自引:7,他引:4 下载免费PDF全文
R Bernstein T Jenkins B Dawson J Wagner G Dewald G C Koo S S Wachtel 《Journal of medical genetics》1980,17(4):291-300
A mentally retarded female child with multiple congenital abnormalities had an abnormal X chromosome and a Y chromosome; the karyotype was interpreted as 46,dup(X)(p21 leads to pter)Y. Prenatal chromosome studies in a later pregnancy indicated the same chromosomal abnormality in the fetus. The fetus and proband had normal female genitalia and ovarian tissue. H--Y antigen was virtually absent in both sibs, a finding consistent with the view that testis-determining genes of the Y chromosome may be suppressed by regulatory elements of the X. The abnormal X chromosome was present in the mother, the maternal grandmother, and a female sib: all were phenotypically normal and showed the karyotype 46,Xdup(X)(p21 leads to pter) with non-random inactivation of the abnormal X. Anomalous segregation of the Xga allele suggests that the Xg locus was involved in the inactivation process or that crossing-over at meiosis occurred. 相似文献
8.
Chromosome abnormalities clustering and its implications for pathogenesis and prognosis in myeloma. 总被引:19,自引:0,他引:19
C S Debes-Marun G W Dewald S Bryant E Picken R Santana-Dávila N González-Paz J M Winkler R A Kyle M A Gertz T E Witzig A Dispenzieri M Q Lacy S V Rajkumar J A Lust P R Greipp R Fonseca 《Leukemia》2003,17(2):427-436
The nonrandom recurrent nature of chromosome abnormalities in myeloma suggests a role for them in disease pathogenesis. We performed a careful cytogenetic analysis of patients with abnormal karyotypes (n = 254), to discern patterns of association, search for novel abnormalities and elucidate clinical implications. Patients with karyotypic abnormalities suggestive of myelodysplasia/acute leukemia were excluded. In this study we compared survival by abnormality only between patients with abnormal karyotypes. Patients with abnormalities were more likely to have features of aggressive disease as compared to all other patients without abnormalities entered into the myeloma database (lower hemoglobin, higher beta(2)-microglobulin, labeling-index and plasmocytosis; all P < 0.0001). Several groups of patients could be readily identified; hypodiploid (22%), pseudodiploid (36%), hyperdiploid (31%) and near-tetraploid (11%). Clustering associations were seen among several trisomies and monosomy of chromosome 13 and 14. Several monosomies (-2, -3, -13, -14 and -19), 1p translocations/ deletions, and hypodiploidy were associated with a significantly shorter survival. Trisomy of chromosome 13 was rare ( <2%). Even among patients with abnormal karyotypes, specific chromosome abnormalities can impart biologic variability in myeloma, including several monosomies, hypodiploidy and abnormalities of 1p. 相似文献
9.
A MacDonald GW Rylance D Asplin SK Hall IW Booth 《Archives of disease in childhood》1998,78(2):122-126
A 1993 MRC working group on phenylketonuria suggested standardising blood phenylalanine measurements by taking blood samples at the same time each day. Since it is not known how representative of a 24 hour period a single phenylalanine concentration is, the aim of this study was to investigate the 24 hour variability of plasma phenylalanine in well controlled children with phenylketonuria. Sixteen subjects, 12 girls and four boys aged 1 to 18 years, had hourly venous blood samples collected for 13 hours between 09.00 and 21.00 on one day. Serial skin puncture blood specimens were then collected at 24.00, 03.00, and 06.00 within the same 24 hour period. All food and drink was weighed. The median variation in plasma phenylalanine concentration was 155 mumol/l/day, with a minimum of 80 and a maximum of 280. The highest concentration occurred in the morning between 6.00 and 9.00 in 63% of subjects; the lowest occurred between midday and midnight in 94%. Concentrations < 100 mumol/l occurred in 46% of children below 11 years, three having concentrations < 30 mumol/l for two, six, and seven hours respectively. Three of five subjects had concentrations above the MRC guidelines for 24% of the period studied. Except in two subjects, the blood concentrations did not rise in response to phenylalanine consumption. However, the greater the quantity of protein substitute taken between waking and the 16.00 specimen, the larger the decrease in daytime phenylalanine concentration (r = -0.7030) (p < 0.005). There is therefore wide variability in phenylalanine concentrations in a 24 hour period in children with phenylketonuria which is not reflected in a single observation. Further study is needed to investigate the effects of timing of protein substitute on the stability of phenylalanine concentrations. 相似文献
10.
Schmitz C Welz A Dewald O Kozlik-Feldmann R Netz H Reichart B 《The Annals of thoracic surgery》2000,69(4):1270-1271
A 9-year-old boy with Kawasaki disease survived after two severe myocardial infarctions. Thereafter pharmacologically untreatable ventricular arrhythmia and rapidly deteriorating heart failure developed in the patient. After 19 days of biventricular and a further 27 days of left univentricular mechanical circulatory support with the Berlin Heart (Cardiotechnica, Berlin, Germany) assist device the boy successfully underwent heart transplantation. At a follow-up of 54 months, the boy is leading an active and unrestricted life. 相似文献