全文获取类型
收费全文 | 871篇 |
免费 | 52篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 31篇 |
妇产科学 | 39篇 |
基础医学 | 70篇 |
口腔科学 | 40篇 |
临床医学 | 63篇 |
内科学 | 200篇 |
皮肤病学 | 20篇 |
神经病学 | 39篇 |
特种医学 | 107篇 |
外科学 | 91篇 |
综合类 | 25篇 |
预防医学 | 56篇 |
眼科学 | 10篇 |
药学 | 107篇 |
中国医学 | 4篇 |
肿瘤学 | 28篇 |
出版年
2021年 | 26篇 |
2020年 | 6篇 |
2019年 | 4篇 |
2018年 | 16篇 |
2017年 | 8篇 |
2016年 | 19篇 |
2015年 | 16篇 |
2014年 | 21篇 |
2013年 | 33篇 |
2012年 | 39篇 |
2011年 | 23篇 |
2010年 | 32篇 |
2009年 | 40篇 |
2008年 | 31篇 |
2007年 | 35篇 |
2006年 | 36篇 |
2005年 | 24篇 |
2004年 | 28篇 |
2003年 | 28篇 |
2002年 | 29篇 |
2001年 | 30篇 |
2000年 | 23篇 |
1999年 | 29篇 |
1998年 | 35篇 |
1997年 | 28篇 |
1996年 | 23篇 |
1995年 | 14篇 |
1994年 | 22篇 |
1993年 | 23篇 |
1992年 | 11篇 |
1991年 | 10篇 |
1990年 | 9篇 |
1989年 | 18篇 |
1988年 | 21篇 |
1987年 | 12篇 |
1986年 | 20篇 |
1985年 | 9篇 |
1984年 | 8篇 |
1983年 | 11篇 |
1982年 | 9篇 |
1981年 | 12篇 |
1980年 | 12篇 |
1978年 | 6篇 |
1977年 | 10篇 |
1976年 | 13篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1968年 | 2篇 |
1967年 | 4篇 |
1966年 | 2篇 |
排序方式: 共有932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.
4.
MP Costi D Tondi M Rinaldi D Barlocco G Cignarella DV Santi C Musiu I Pudu G Vacca P La Colla 《European journal of medicinal chemistry》1996,31(12):1011-1016
A new series of N-(substituted)benzyl-1,8-naphthalimides 4, structurally related to the previously reported thymidylate synthase (TS) inhibitor naphthaleins 3, were synthesized and compounds tested for their inhibition of several species of TS. Moreover, their in vitro cytotoxicity together with antimycotic and antibacterial properties were assayed. While no activity was detected in the antibacterial tests, the m-nitro (4ae) and the p-nitro (4af) derivatives were found able to partially inhibit TS at low micromolar concentrations. Introduction of nitro or (substituted)-amino groups in position 4 of the naphthalic ring always led to less active compounds. 相似文献
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.
The authors report their experience in the study of renal transplant recipients by MR, in order to determine its clinical potentials. The main purpose of this work is to focus on MR patterns in relation to clinical findings of rejected or normally functioning kidney. Twenty-four patients were examined with a 0.5 T superconductive magnet, body coil, spin-echo pulse sequence (SE) and inversion-recovery (IR). MRI patterns could be seen in normally functioning kidneys and transplant rejections, while variable MRI findings were observed in transplants with acute tubular necrosis (ATN). In the normally functioning transplanted kidney there is a clear corticomedullary differentiation (CMD), and the extent of vascular penetration into the renal parenchyma is clearly seen. In transplant rejection, CMD is either diminished or absent, and there is no vascular penetration into the parenchyma; to differentiate acute from chronic rejections, the increase/decrease in renal size and the change in renal shape (spherical shape in acute transplant rejection) respectively must be observed. MRI proves thus to be useful in the study of renal transplants, even in case of questionable clinical findings, and in patients in whom renal biopsy is contraindicated. 相似文献
7.
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
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.
Since its inception in November 1997, the Cervical Cancer Screening Program of Paraná (CCSPP), Brazil, has resulted in the cytological screening of 2,244,158 women, the coverage of the female population increasing from 43% to 86%. One thousand six hundred one cases screened by cytology, submitted to colposcopy, and subjected to treatment were selected. Cytopathological results were compared with those obtained on the basis of histological analyses of the loop electrical excision procedure specimens, and were subjected to statistical analyses. The data obtained were then compared with cytohistological correlation results from the first year of the program. Considering the exact correlation between cytological and histological diagnoses, the correlation index increased from 53.34% in the first year to 67.3% at the end of 5 yr of the program. Variations that occurred in each diagnostic category are discussed. This study demonstrates a significant improvement in the concordance between cytological and histological results for the 5-yr period compared with the first year of the CCSPP. 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