全文获取类型
收费全文 | 1062篇 |
免费 | 76篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 58篇 |
妇产科学 | 8篇 |
基础医学 | 93篇 |
口腔科学 | 29篇 |
临床医学 | 170篇 |
内科学 | 214篇 |
皮肤病学 | 13篇 |
神经病学 | 28篇 |
特种医学 | 252篇 |
外科学 | 94篇 |
综合类 | 21篇 |
预防医学 | 41篇 |
眼科学 | 7篇 |
药学 | 78篇 |
中国医学 | 6篇 |
肿瘤学 | 30篇 |
出版年
2024年 | 3篇 |
2023年 | 8篇 |
2021年 | 9篇 |
2020年 | 6篇 |
2019年 | 6篇 |
2018年 | 22篇 |
2017年 | 12篇 |
2016年 | 18篇 |
2015年 | 20篇 |
2014年 | 26篇 |
2013年 | 26篇 |
2012年 | 16篇 |
2011年 | 19篇 |
2010年 | 41篇 |
2009年 | 58篇 |
2008年 | 31篇 |
2007年 | 14篇 |
2006年 | 20篇 |
2005年 | 9篇 |
2004年 | 15篇 |
2003年 | 19篇 |
2002年 | 18篇 |
2001年 | 24篇 |
2000年 | 13篇 |
1999年 | 16篇 |
1998年 | 51篇 |
1997年 | 53篇 |
1996年 | 66篇 |
1995年 | 49篇 |
1994年 | 43篇 |
1993年 | 47篇 |
1992年 | 15篇 |
1991年 | 11篇 |
1990年 | 19篇 |
1989年 | 40篇 |
1988年 | 35篇 |
1987年 | 37篇 |
1986年 | 38篇 |
1985年 | 27篇 |
1984年 | 19篇 |
1983年 | 11篇 |
1982年 | 26篇 |
1981年 | 17篇 |
1980年 | 9篇 |
1979年 | 8篇 |
1978年 | 10篇 |
1977年 | 12篇 |
1976年 | 12篇 |
1975年 | 13篇 |
1969年 | 2篇 |
排序方式: 共有1145条查询结果,搜索用时 15 毫秒
11.
Carol Smillie B.N. B.Ed. M.S.C. Katherine Coffin B.A. ME.D. Kathryn Porter B.A. Brenda Ryan B.A. M.B.A. 《Journal of community health》1988,13(3):156-170
The International Conference on Primary Health Care, meeting in Alma-Ata, in the Soviet Union, September 12, 1978, expressed the need for urgent action by all governments, all health and development workers and the world community, to protect and promote the health of all people of the world. The world was caught by the phrase which emerged from this conference, Health For All by the Year 2000 and many have examined the articles of the Alma-Ata declaration and tried to implement them in their corner of the world. This paper describes a community-based smoking-cessation program which was implemented in the province of Nova Scotia, Canada, during the years 1980–1984. Primary to this project was the belief that people have the right and the duty to participate individually and collectively in planning and implementing their health care. This paper describes one community's effort in putting this belief into practice.Carol Smillie, B.N. BE.d. M.S.c. is an Assistant Professor at the School of Nursing, Dalhousie University, Halifax, Nova Scotia, Canada B3H 3J5, Katherine Coffin, BA, MEd is the Program Officer, Nova Scotia Office, Health Promotion Directorate Health and Welfare Canada, 5251 Duke Street, Halifax, Nova Scotia. Canada B3J 1P3. Kathryn Porter, B.A. (Gen)., is the Information and Education Coordinator, Nova Scotia Division Canadian Cancer Society. Brenda Ryan, B.A., M.B.A. is Program Evaluation Analysist, Nova Scotia Department of Health, 6088 Hollis Street, Halifax. Nova Scotia, Canada. This Project was funded by Health and Welfare Canada, Nova Scotia Department of Health, Nova Scotia Division Canadian Cancer Society, Requests for reprints should be addressed to: Professor Carol Smillie. 相似文献
12.
Carlo Alberto Maggi Riccardo Patacchini Paolo Santicioli Sandro Giuliani Damiano Turini Gabriele Barbanti Patrizia Beneforti Daniele Misuri Alberto Meli 《Naunyn-Schmiedeberg's archives of pharmacology》1989,339(4):415-423
Summary (1) Longitudinal muscle strips from the human small intestine (jejunum/ileum) responded to electrical field stimulation (1–50 Hz) with frequency-related primary contractions which were largely atropine- (3 M) sensitive. When the tone was raised by addition of galanin (0.3 – 1 M), prostaglandin (PG) E2 (1–10 M) or neurokinin A (NKA, 0.1 M), a frequency-related relaxation was evident which was potentiated by atropine. All the responses to field stimulation were abolished by tetrodotoxin (1 M), thus indicating their neural origin. (2) The atropine-sensitive primary contraction to field stimulation was virtually abolished by omega conotoxin fraction GVIA (CTX, 0.1–0.3 M) while the relaxations were CTX-resistant. The field stimulation-induced relaxations, which were observed in the presence of atropine and guanethidine (3 M), were also unaffected by apamin (0.1 M). (3) NKA and substance P (SP) produced a concentration- (1 nM–1 M for both peptides) related contraction, NKA being about 53 times more potent than SP. [Pro9]SP sulphone and [MePhe7]-NKB, selective agonists of the NK-1 and NK-3 receptor, respectively, were barely effective. On the other hand, [\Ala8]NKA(4–10), a selective NK-2 receptor agonist, had a potent contractile activity, similar to that of NKA. (4) Galanin (1 nM–1M) produced an atropine- and tetrodotoxin-resistant concentration-related contraction of longitudinal muscle of human isolated small intestine. The response to galanin did not show any sign of fading and was particularly suitable to study the evoked relaxations. (5) Calcitonin gene-related peptide (CGRP) (10–100 nM) consistently inhibited the nerve-mediated contractions of strips from the ileum while the effect on the jejunum was less pronounced. Vasoactive intestinal polypeptide (VIP, 0.1–1 M) inhibited nerve-mediated contractions both in the ileum and the jejunum. (6) These experiments indicate that both cholinergic excitatory and non-adrenergic non-cholinergic nerves affect motility of the longitudinal muscle of the human small intestine. Furthermore, several neuropeptides produce potent motor effects, the contractile response to tachykinins being apparently mediated by activation of NK-2 receptors. 相似文献
13.
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
14.
15.
16.
17.
Mai A Artico M Valente S Sbardella G Turini P Befani O Vedova LD Agostinelli E 《Medicinal chemistry (Shāriqah (United Arab Emirates))》2005,1(2):117-124
A novel series of 5-substituted-3-(1H-pyrrol-2-yl)-2-oxazolidinones 2a-s has been described as pyrrole analogues of toloxatone and befloxatone, two phenyl-oxazolidinones active as anti-MAO agents and used in antidepressant therapy. Tested against MAO-A and MAO-B enzymes, the majority of 2a-s show highly potent inhibitory effect against the A isoform of the enzyme, with Ki values in the range 0.52-0.004 microM, whilst their anti-MAO-B activity is considerably lower (Ki = >100-0.5 microM). Structurally, 2a-s differs for the substituent inserted at the C5 position of the 2-oxazolidinone ring (hydroxymethyl (2a-d), methoxymethyl (2e-h), azidomethyl (2i-l), methylaminomethyl (2m-p), and aminomethyl (2q-s)), and the size of the alkyl chain at the pyrrole N1 position (methyl, ethyl, allyl, or benzyl). As a rule, apart from the C5 substitution, the bulkier is the alkyl group at the pyrrole-N1, the lower is the anti-MAO-A activity of the compounds, being the N1-methyl derivatives 2a, 2e, 2i, and 2q among the most potent (K(iMAO-A) = 0.087-0.004 microM) and A-selective (A-selectivity ratio: >11,111-41) compounds in this series. Exceptions are represented by the N1-benzyl derivative 2d (K(iMAO-A) = 0.009 microM) and the N1-allylpyrrole 2o (K(iMAO-A) = 0.04 microM). In comparison with the reference drugs, these highly active derivatives are more potent than toloxatone, slightly less potent than befloxatone, and several times more A-selective than both the references. Such results indicate that 2a-s may represent a new promising series of antidepressant agents. 相似文献
18.
A second locus (GLC3B) for primary congenital glaucoma (Buphthalmos) maps to the 1p36 region 总被引:10,自引:0,他引:10
Akarsu AN; Turacli ME; Aktan SG; Barsoum-Homsy M; Chevrette L; Sayli BS; Sarfarazi M 《Human molecular genetics》1996,5(8):1199-1203
Primary congenital glaucoma (gene symbol: GLC3) is an ocular disorder that
occurs for 0.01-0.04% of blind people. In the majority of familial cases
reported so far, this condition is inherited as an autosomal recessive
trait. We have recently used a group of 17 GLC3 families with a minimum of
two affected offspring and consanguinity in most of the parental generation
and mapped the first GLC3 locus (GLC3A) to the 2p21 region. Six families
did not show any linkage to the GLC3A locus and thus provided evidence for
genetic heterogeneity of this disorder. A total of eight families unlinked
to the 2p21 region were used to search for the chromosomal location of the
second GLC3 locus. Herein, we describe mapping of a new locus (designated
GLC3B) for primary congenital glaucoma to the short arm of chromosome 1
(1p36.2-36.1) that is situated centromeric to the neuroblastoma and
Charcot-Marie-Tooth type 2A (CMT2A) loci. A total of 17 DNA markers were
genotyped from this region of chromosome 1. Four families showed no
recombination with the two markers D1S2834 and D1S402 with a maximum lod
score of 4.510 and 4.157 respectively. Pairwise and multipoint linkage
analysis and inspection of the haplotypes revealed that the remaining four
families are not linked to this part of chromosome 1, thus providing
further evidence that at least one more locus for the autosomal recessive
form of GLC3 must exist in the genome. Based on the recombination events,
the overall linkage map of this region is: tel-D1S1192-D1S1635-D1S1193 -
(D1S1597/-D1S489/D1S228)- [GLC3B/D1S2834/D1S402] - (D1S1176/D1S507/D1S407)
- D1S2728-(MFAP2/D1S170) - D1S1368 - D1S436- D1S1592-cen.
相似文献
19.
Striated intramural gallbladder lucencies on US studies: predictors of acute cholecystitis 总被引:1,自引:0,他引:1
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent. 相似文献
20.
Xuejin Ma ME Xiaoxi Chen MD Guoyuan Jiang MBBS Lin Jiang MD Tingchao Li MBBS Ling Wei MBBS Shiguang Li MD 《The breast journal》2021,27(12):890-894
Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type. 相似文献