全文获取类型
收费全文 | 1004篇 |
免费 | 81篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 37篇 |
儿科学 | 84篇 |
妇产科学 | 14篇 |
基础医学 | 108篇 |
口腔科学 | 47篇 |
临床医学 | 75篇 |
内科学 | 165篇 |
皮肤病学 | 20篇 |
神经病学 | 81篇 |
特种医学 | 122篇 |
外科学 | 93篇 |
综合类 | 26篇 |
预防医学 | 52篇 |
眼科学 | 5篇 |
药学 | 68篇 |
中国医学 | 1篇 |
肿瘤学 | 94篇 |
出版年
2021年 | 22篇 |
2020年 | 13篇 |
2019年 | 4篇 |
2018年 | 15篇 |
2017年 | 7篇 |
2016年 | 24篇 |
2015年 | 22篇 |
2014年 | 26篇 |
2013年 | 49篇 |
2012年 | 50篇 |
2011年 | 35篇 |
2010年 | 36篇 |
2009年 | 47篇 |
2008年 | 34篇 |
2007年 | 36篇 |
2006年 | 45篇 |
2005年 | 33篇 |
2004年 | 27篇 |
2003年 | 28篇 |
2002年 | 22篇 |
2001年 | 24篇 |
2000年 | 22篇 |
1999年 | 31篇 |
1998年 | 44篇 |
1997年 | 32篇 |
1996年 | 29篇 |
1995年 | 16篇 |
1994年 | 27篇 |
1993年 | 26篇 |
1992年 | 17篇 |
1991年 | 15篇 |
1990年 | 10篇 |
1989年 | 21篇 |
1988年 | 21篇 |
1987年 | 14篇 |
1986年 | 18篇 |
1985年 | 10篇 |
1984年 | 12篇 |
1983年 | 11篇 |
1982年 | 14篇 |
1981年 | 14篇 |
1980年 | 14篇 |
1978年 | 8篇 |
1977年 | 8篇 |
1976年 | 12篇 |
1975年 | 4篇 |
1974年 | 4篇 |
1972年 | 6篇 |
1967年 | 4篇 |
1957年 | 4篇 |
排序方式: 共有1092条查询结果,搜索用时 15 毫秒
1.
BARI NUHOLU ALI AYYILDIZ VECIHI FIDAN ÖZDEN CEBECI UUR KOAR CANKON GERMIYANOLU 《International journal of urology》2006,13(2):109-110
OBJECTIVE: Nocturnal enuresis is a common pediatric problem, the etiology of which is unclear. In recent years, various studies have been published stating that children with nocturnal enuresis exhibit growth and skeletal maturation retardation. METHODS: In this cross-sectional study, we included 27 patients (16 boys, 11 girls) between the ages of 6 and 14 years who had presented with primary nocturnal enuresis (PNE) complaints. We included in the evaluation 19 healthy subjects (12 boys, 7 girls), who were the siblings of the children with PNE, as the control group. RESULTS: The patients in both groups were similar in chronological age, bone age, height and weight, with no significant difference between groups (P>0.05). CONCLUSION: The two groups in our study consisted of the same genetic background. Thus, our results were found to be different from the previous studies. We have concluded that there is no direct relationship between enuresis nocturnal and skeletal maturation. 相似文献
2.
3.
The relationship between the immunological and biological activities of thyroid-stimulating hormone (TSH) isoforms present in the three human pituitary preparations 68/38 (1st IRP), 80/558 (2nd IRP) and 63/14 (MRC Research Standard A) was investigated. The isoforms were separated by chromatofocusing. Six peaks of immunoactivity were detected in 80/558, with pI values (means +/- S.E.M.) of 6.6 +/- 0.1, 6.2 +/- 0.1, 5.9 +/- 0.1, 5.5 +/- 0.1, 5.2 +/- 0.1 and 4.9 +/- 0.1. Four peaks, with pI values of 6.8 +/- 0.1, 5.9 +/- 0.1, 5.5 +/- 0.1 and 5.2 +/- 0.1, were observed for 68/38. Standard 63/14 had five peaks, with pI values of 6.9 +/- 0.1, 6.4 +/- 0.1, 5.9 +/- 0.1, 5.4 +/- 0.1 and 4.9 +/- 0.1. For each standard, six fractions around the peak areas and at the top and bottom of the gradient were pooled and microconcentrated to < 1.0 ml. Microconcentrated TSH samples were assayed in three TSH bioassays based upon FRTL-5 thyroid cells, utilizing cyclic AMP accumulation, iodide and thymidine uptake as end-points and standard 80/558 as reference preparation. The more acidic forms of TSH showed a higher biological:immunological (B:I) ratio for cyclic AMP accumulation with, for example, 63/14 having a maximum of 3.7 (pI 4.9) and a minimum of < 0.7 (pI 6.9). In contrast, the maximum and minimum B:I ratios for iodide uptake for 63/14 were 3.8 (pI 6.9) and < 0.8 (pI 4.6), and for thymidine uptake, maximum and minimum ratios were 7.2 (pI 6.9) and 1.1 (pI 4.6) respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
5.
Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients 总被引:1,自引:1,他引:0
al-Wakeel JS; Mitwalli AH; Huraib S; al-Mohaya S; Abu-Aisha H; Chaudhary AR; al-Majed SA; Memon N 《Nephrology, dialysis, transplantation》1997,12(7):1420-1424
High serum fluoride (F-) in patients with chronic renal failure (CRF) and
end-stage renal disease (ESRD) is associated with risk of renal
osteodystrophy and other bone changes. This study was done to determine F-
in normal healthy controls and patients with ESRD on haemodialysis (HD) or
peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females)
and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in
the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l)
of F- content in drinking water. Control subjects showed a mean serum F-
concentration of 1.08 +/- 0.350 microM/l. Males in control group showed
slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than
females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F-
concentration did not correlate significantly with age and sex among
control subjects, whereas such correlation was observed in patients with
ESRD on dialysis. Mean serum F- concentration was significantly higher in
patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal
controls. When grouped according to sex, the mean serum F- concentration in
males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than
females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped
according to age, it was observed that F- concentration was significantly
higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with
age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated
with age and sex, being higher in males and above 20 years. Despite
appreciable clearance of F- (39-90%) across the peritoneum, patients on
CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs
2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their
serum F- concentration above 3.0 microM/l, posing the risk of renal
osteodystrophy.
相似文献
6.
AR Jones BSC AJP Sandison FRCS WJ Owen MS FRCS 《International journal of clinical practice》1997,51(5):294-295
Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons. 相似文献
7.
The cochleae of anaesthetized guinea pigs were prepared for scanning electron microscopy, immediately after exposure to an intense tone. Stereocilia on hair cells showing relatively small degrees of disruption were analyzed. If the bundles of stereocilia showed no or only a very slight degree of disorganization, the fine links emerging from the tips of the shorter stereocilia remained intact. If the stereocilia were separated more than a very little, the tip links between stereocilia were no longer visible. However, it was possible for tip links to remain intact in some parts of the hair bundle, while tip links in other, more disrupted parts, were lost. In outer hair cells, tip links did not seem any more vulnerable in one position than in another. In inner hair cells, it was commonly found that the tip links running between the tallest stereocilia and the next row of shorter stereocilia had broken, while the tip links running between the other shorter rows of stereocilia remained intact. The results suggest that tip links between stereocilia are preserved as long as the other links between the stereocilia and the cytoskeleton of the stereocilium remain intact. When the latter are damaged the tip links fracture. The results also suggest that, if the tip links are indeed involved in transduction, some degree of stimulus transduction can continue in damaged inner hair cells, albeit with a reduced sensitivity. 相似文献
8.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
9.
The effect of conduct disorder on adult social functioning in the areas of work, sexual/love relationships, social relationships and criminality was studied in a sample of young adults who spent much of their childhoods in group-cottage children's homes and an inner-city comparison group. Most subjects with conduct disorder had pervasive (but not necessarily severe) social difficulties compared to peers without conduct disorder. Less than half of this group met DSM-III adult criteria for antisocial personality disorder and just over half were given a diagnosis of personality disorder on interviewer clinical ratings. A latent class model that used both the retrospective and contemporaneous indicators of conduct disorder confirmed the very high continuity with adult social difficulties. Current diagnoses did not adequately describe this group and conduct disorder appeared to be an almost necessary condition for multiple social disability in adults in these samples. 相似文献
10.
P?Mallick J?Chakrabarti Mallick B?Guha AR?Khuda-BukhshEmail author 《BMC complementary and alternative medicine》2003,3(1):7