全文获取类型
收费全文 | 1443篇 |
免费 | 43篇 |
国内免费 | 75篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 50篇 |
妇产科学 | 39篇 |
基础医学 | 181篇 |
口腔科学 | 21篇 |
临床医学 | 159篇 |
内科学 | 330篇 |
皮肤病学 | 39篇 |
神经病学 | 84篇 |
特种医学 | 269篇 |
外科学 | 126篇 |
综合类 | 30篇 |
预防医学 | 57篇 |
眼科学 | 26篇 |
药学 | 75篇 |
中国医学 | 3篇 |
肿瘤学 | 64篇 |
出版年
2023年 | 7篇 |
2021年 | 16篇 |
2020年 | 11篇 |
2019年 | 12篇 |
2018年 | 17篇 |
2016年 | 14篇 |
2015年 | 20篇 |
2014年 | 22篇 |
2013年 | 27篇 |
2012年 | 32篇 |
2011年 | 32篇 |
2010年 | 44篇 |
2009年 | 60篇 |
2008年 | 35篇 |
2007年 | 65篇 |
2006年 | 43篇 |
2005年 | 51篇 |
2004年 | 29篇 |
2003年 | 29篇 |
2002年 | 25篇 |
2001年 | 38篇 |
2000年 | 42篇 |
1999年 | 24篇 |
1998年 | 90篇 |
1997年 | 72篇 |
1996年 | 69篇 |
1995年 | 54篇 |
1994年 | 46篇 |
1993年 | 49篇 |
1992年 | 28篇 |
1991年 | 25篇 |
1990年 | 30篇 |
1989年 | 41篇 |
1988年 | 46篇 |
1987年 | 32篇 |
1986年 | 29篇 |
1985年 | 32篇 |
1984年 | 21篇 |
1983年 | 20篇 |
1982年 | 22篇 |
1981年 | 11篇 |
1980年 | 19篇 |
1979年 | 10篇 |
1978年 | 15篇 |
1977年 | 21篇 |
1976年 | 16篇 |
1975年 | 18篇 |
1974年 | 6篇 |
1972年 | 6篇 |
1970年 | 6篇 |
排序方式: 共有1561条查询结果,搜索用时 27 毫秒
11.
12.
In any case of latent syphilis without conclusive history, an examination of the cerebrospinal fluid (CSF) is generally recommended. The present paper deals with the question whether particular findings obtained by serologic tests on the blood can supply sufficient proof to rule out any specific involvement of the central nervous system in an individual patient. Serologic investigation on 148 blood-CSF sample pairs revealed striking correlations between several blood and CSF parameters on a high level of statistical significance. Based on blood serology data alone, a multi-dimensional, non-parametric statistical test (the k-nearest-neighbor method) was able to rule out specific involvement of the CSF in more than one third of the patients. We consider our approach useful in certain cases where CSF examination should rather be avoided, especially in patients with impaired general condition due to other diseases. Yet, in any case of neurological irregularity, CSF examination should generally be carried out regardless of the results of blood serology. 相似文献
13.
CA Schroeter† L Kaas† JJ Waterval† PM Bos‡ HAM Neumann§ 《Journal of the European Academy of Dermatology and Venereology》2007,21(9):1170-1174
AIM: The aim of this pilot study was an investigation on photodynamic therapy (PDT) whether it is a good alternative for treating periungual and subungual warts of the hands. STUDY DESIGN: Twenty patients (mean age: 30.5 years) with a total of 40 periungual and subungual warts were treated with PDT. A photosensitizer, 20%delta-aminolevulinic acid was applied on the warts. After a mean incubation time of 4.6 h (SD: 1.2), the warts were irradiated with the VersaLight for 5-30 min (15.2 +/- 4.3 min). RESULTS: After a mean of 4.5 treatments a mean clearance of 100% was achieved in 90% of the patients. One patient (5%) showed a clearance of 50% and another showed no improvement. The subungual or periungual location of the wart had no influence on the number of treatments or end result (P > 0.05). There were two recurrences during the mean follow-up period of 5.9 months (SD: 7.6). Besides mainly pain and hyperpigmentation, most treatments had no side-effects. CONCLUSION: PDT can offer a good alternative for treating periungual warts of the hands. Larger studies are indicated. 相似文献
14.
JJ Piccininni 《The Journal of the Canadian Chiropractic Association》1994,38(4):223-226
This paper examines various devices used in strength building exercise programs. These include free weights, pulley machines, variable resistance weight machines, isokinetic units and elastic tubing and banding. Advantages and disadvantages of each are discussed and examined from the view point of the health care provider and the suitability of each type of device for prescribed progressive resistance exercise programs for patients. In addition to such practical aspects such as cost and maintenance, biomechanical factors, types of contraction elicited, ease of patient instruction and proprioception benefits are also compared in order to assist the clinician in selecting the most appropriate equipment for each individual patient. 相似文献
15.
16.
17.
18.
Verschuren MC; Blom B; Bogers AJ; Spits H; van Dongen JJ 《International immunology》1998,10(12):1873-1880
Recombination of deltaRec to psiJalpha will delete the TCR delta gene,
which is thought to play an important role in the bifurcation of the TCR
alphabeta versus TCR gammadelta differentiation lineages. We recently
detected a DNA-binding protein in human thymocytes, the so- called PJA-BP,
which recognizes the psiJalpha gene segment and might be one of the factors
involved in the regulation of preferential deltaRec- psiJalpha
rearrangements. We now investigate PJA-BP expression and its correlation
with TCR delta gene deletion in thymocytes. Our electrophoretic mobility
shift assay experiments showed that the PJA-BP is evolutionary conserved in
human, murine and simian thymocytes. Using a large series of human
hematopoietic malignancies (n = 30), we conclude that PJA-BP expression is
thymocyte specific and seems to be restricted to thymocytes committed to
the TCR alphabeta lineage. Analysis of seven well-defined human thymocyte
subpopulations showed that preferential deltaRec-psiJalpha rearrangements
as well as PJA-BP expression can be detected from the immature
CD34-/CD1+/CD3- /CD4+/CD8alpha+beta- thymocyte differentiation stage
onwards. These experiments indicate that expression of PJA-BP in human
thymocytes starts simultaneously with preferential deltaRec-psiJalpha
rearrangements, which supports our hypothesis that PJA-BP is one of the
factors involved in the preferential recombination of deltaRec to
psiJalpha.
相似文献
19.
Del-Favero J; Krols L; Michalik A; Theuns J; Lofgren A; Goossens D; Wehnert A; Van den Bossche D; Van Zand K; Backhovens H; van Regenmorter N; Martin JJ; Van Broeckhoven C 《Human molecular genetics》1998,7(2):177-186
Autosomal dominant cerebellar ataxia with retinal degeneration (ADCAII) was
previously mapped by linkage analysis studies to chromosome 3p12- p21.1
(SCA7). Positional cloning efforts have recently identified a novel gene,
SCA7 , containing a translated CAG repeat, expanded in SCA7 patients. We
cloned the SCA7 gene from a yeast artificial chromosome (YAC) clone contig
spanning the SCA7 candidate region. Using a combination of genomic
sequencing and cosmid-based exon trapping, two expressed sequence tags were
identified. Sequencing of the corresponding cDNA clones and RT-PCR analysis
identified the full- length SCA7 cDNA. Together, our sequence data defined
the intron/exon boundaries of the first two coding exons of the SCA7 gene,
with the first exon containing the expanded CAG repeat. Further, sequence
comparison with the published SCA7 cDNA identified one additional putative
exon in the 5'-UTR region of the SCA7 gene. The SCA7 gene was mapped on the
YAC contig in the 2.5 cM interval between D3S1600 and D3S1287. In one
extended Belgian SCA7 pedigree the expanded alleles ranged from 38 to at
least 55 repeats with allele lengths being inversely correlated with onset
age of ADCAII symptoms. The SCA7 repeats increased in length in successive
generations. Normal alleles had from four to 18 repeats, with 10 repeats
being the most common allele.
相似文献
20.
JJ Favre Ph Chaffanjon JG Passagia JP Chirossel 《Surgical and radiologic anatomy : SRA》1995,17(2):133-138
Summary The authors report the results of a series of dissections and anatomic sections of the fronto-basal region of the brain and of the anterior cranial fossa in human cadavers. The constant presence of an arachnoidal cistern above the olfactory nerve was verified. The arachnoid separates from the pial membrane and forms a bridge with the ventral part of the olfactory bulb and tract, from the lateral edge of the olfactory sulcus to the medial edge of the gyrus rectus. The cistern is wide in its anterior portion, between the gyrus rectus and the olfactory bulb, and is reduced to a virtual slit in its posterior portion where the tract is lodged in the olfactory sulcus. The olfactory nerve can be separated without damaging fronto-basal arachnoidial adhesions over several centimeters. Dissection of this region after intravascular injection of colored media shows the constant presence of an artery destined to the olfactory bulb and tract. It originates either from the lateral surface of the anterior cerebral a. (segment A2), or from the medial fronto-basal a., and consistently provides terminal branches in front of the olfactory trigone in the medial olfactory sulcus. At their ventral extremity, the olfactory structures are therefore vascularised independently for several centimeters, from the lower face of the frontal lobe. The independent vascularisation of the olfactory nerve, the tenuous and easily detachable adhesions, and the actual presence of a true arachnoidal cistern all contribute to enabling surgical techniques which conserve olfactory function during anterior approaches.
Vascularisation du nerf olfactif. Rapports méningés et applications chirurgicales
Résumé Les auteurs rapportent les résultats d'une série de dissections et de coupes de la région fronto-basale de l'encéphale et de la fosse crânienne antérieure sur sujets cadavériques. La présence constante d'une citerne arachnoïdienne au dessus du n. olfactif a été vérifiée. L'arachnoïde se sépare du feuillet pial et passe en pont à la partie ventrale du bulbe et du tractus olfactifs, du bord latéral du sillon olfactif au bord médial du gyrus rectus. La citerne est large dans sa portion antérieure, entre le gyrus rectus et le bulbe olfactif, se réduit à une fente virtuelle postérieure lorsque le tractus se loge dans le sillon olfactif. Le n. olfactif peut être séparé sans dommage des adhérences arachnoïdiennes fronto-basales sur quelques centimètres. La dissection de cette région, après injection intravasculaire de masses colorées montre, de façon originale, la présence constante d'une artère destinée au tractus et au bulbe olfactifs. Elle naît soit de la face latérale de l'a. cérébrale antérieure (segment A2), soit de l'a. fronto-basale médiale, pour donner ses branches terminales toujours en avant du trigone olfactif dans le sillon orbitaire médial. Sur quelques centimètres à leur extrémité ventrale, les structures olfactives ont donc une vascularisation indépendante de la face inférieure du lobe frontal. L'indépendance vasculaire du n. olfactif, des adhérences ténues, facilement détachables, et la réalité vérifiée d'une véritable citerne arachnoïdienne permettent d'imaginer des techniques conservatrices de la fonction olfactive utilisées dans plusieurs indications de la chirurgie de la fosse crânienne antérieure.相似文献