全文获取类型
收费全文 | 2189篇 |
免费 | 146篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 100篇 |
妇产科学 | 87篇 |
基础医学 | 231篇 |
口腔科学 | 49篇 |
临床医学 | 170篇 |
内科学 | 587篇 |
皮肤病学 | 107篇 |
神经病学 | 150篇 |
特种医学 | 87篇 |
外国民族医学 | 1篇 |
外科学 | 345篇 |
综合类 | 21篇 |
预防医学 | 152篇 |
眼科学 | 26篇 |
药学 | 93篇 |
中国医学 | 8篇 |
肿瘤学 | 109篇 |
出版年
2023年 | 9篇 |
2022年 | 19篇 |
2021年 | 47篇 |
2020年 | 35篇 |
2019年 | 50篇 |
2018年 | 64篇 |
2017年 | 45篇 |
2016年 | 44篇 |
2015年 | 52篇 |
2014年 | 70篇 |
2013年 | 96篇 |
2012年 | 142篇 |
2011年 | 122篇 |
2010年 | 81篇 |
2009年 | 98篇 |
2008年 | 102篇 |
2007年 | 106篇 |
2006年 | 91篇 |
2005年 | 94篇 |
2004年 | 114篇 |
2003年 | 96篇 |
2002年 | 83篇 |
2001年 | 54篇 |
2000年 | 96篇 |
1999年 | 68篇 |
1998年 | 36篇 |
1997年 | 35篇 |
1996年 | 36篇 |
1995年 | 27篇 |
1994年 | 31篇 |
1993年 | 12篇 |
1992年 | 34篇 |
1991年 | 33篇 |
1990年 | 18篇 |
1989年 | 15篇 |
1988年 | 23篇 |
1987年 | 17篇 |
1986年 | 21篇 |
1985年 | 15篇 |
1984年 | 13篇 |
1983年 | 9篇 |
1982年 | 15篇 |
1981年 | 8篇 |
1979年 | 7篇 |
1978年 | 8篇 |
1977年 | 7篇 |
1976年 | 7篇 |
1975年 | 8篇 |
1974年 | 7篇 |
1971年 | 8篇 |
排序方式: 共有2359条查询结果,搜索用时 328 毫秒
11.
X Sala-Barangé R Vilana C Ribas M Marquez X Iglesias Gu?u 《Journal de radiologie》1988,69(8-9):539-541
The authors explain the clinical case of a female patient suffering from secondary sterility; she was submitted, among other test, to the H.S.G. in order to study the possibility of a among other tests, to the H.S.G. in order to study the possibility of a cervical failure. The radiological findings obtained of Morgagni's Hydatis, not described previously in literature and their laparoscopic confirmation justify, we believe, its publication. 相似文献
12.
F Calero J Jimeno F Rodríguez-Escudero J Asins Codoner J Mendana J Iglesias F Murillo F Ugalde A Armas A Rementería 《European journal of gynaecological oncology》1992,13(1):83-89
We have evaluated the clinical toxicity of Epirubicin 80 mg/m2 i.v., every 3 weeks in 58 patients with FIGO III-IV endometrial adenocarcinoma or squamous uterine cervix carcinoma. The median age of the whole group was 59 years (37-77); 37 patients were previously treated with radiotherapy and two with cisplatin based chemotherapy. The median KI at entry was 80. A total of 308 courses of chemotherapy were administered with a median of 5 per patient. Overall toxicity data shows that this dose level is associated with mild haematological toxicity with only two cases having grade 3 (WHO) leukopenia. Nine patients suffered emesis in spite of prophylactic therapy and were classified as grade 3. One case presented grade four diarrhoea but the relation with the antineoplastic treatment was uncertain. One woman with hepatic dysfunction at entry had grade 3 leukopenia, developed pneumonia and died. The median total cumulative dose of EPI was 360 mg/m2 (160-880) with 19 cases exposed to cumulative doses higher than 550 mg/m2. Congestive heart failure was not observed. Our data confirm the safety of EPI at these dose levels and suggest the possibility of developing new trials with higher doses of this anthracycline analog. 相似文献
13.
J Barba J A Gómez A C Abecia I Iglesias C Díaz A Pellicelli D Lozano J Herreros R Llorens D Martínez Caro 《Revista espa?ola de cardiología》1992,45(10):652-656
In acute cardiac rejection, left ventricular diastolic function is altered. To study these abnormalities and their utility in cardiac allograft rejection, we studied 56 cardiac transplant recipients. All patients were assessed with endomyocardial biopsy and Doppler echocardiography done in the same day. A total of 163 Doppler studies were recollected. Cardiac transplant recipients were excluded during the early 6 weeks postoperative period. Totally, 100 biopsies were normal, 48 positive for mild rejection (Billingham Gde I-II) and 15 positive for moderate or severe rejection (Billingham Gde III-IV). Compared to negative biopsies, during acute rejection left ventricular wald thickness significantly increased (p < 0.05); isovolumic relaxation period and pressure half-time significantly decreased (p < 0.05, p < 0.001 respectively). Nevertheless, increase in peak early mitral flow velocity was only significantly associated with severe rejection (p < 0.001). Correlating only progressive shortening of isovolumic relaxation period parameter in the diagnosis of graft rejection, we forward a high sensibility (85%) and low specificity (57%). Thus, Doppler echocardiographic evaluation of left ventricular diastolic function provides a non-invasive tool for early detection of acute rejection monitoring after the early postoperative period. 相似文献
14.
J L Martínez Sande A Amaro Cendón E Blanco Labrador M Pérez Rodríguez A Sánchez Prieto C Iglesias Carre?o M Gil de la Pe?a 《Revista espa?ola de cardiología》1992,45(8):545-548
A 32-year old woman, with endocarditis caused by Streptococcus mitis, and systolic murmur is presented. The Doppler examination was found a systolic gradient of 150 mmHg. Aortography showed a multiple membranous supravalvular aortic stenosis, with aneurysmal dilatation of the left main coronary artery and circumflex artery, associated with bicuspid aortic valve and mild aortic insufficiency. The patient died suddenly by cardiac arrest in stand by to cardiac surgery. Anatomic comprobation was not possible. The coronary artery anomalies associated with the supravalvular aortic stenosis syndrome are reviewed. 相似文献
15.
J B Iglesias 《Revue de laryngologie - otologie - rhinologie》1991,112(1):89-90
This paper reports on the improvement of the usual technique of indirect laryngoscopy, through the use of an operating microscope with a straight eyepiece and a 300 mm lens in the place of the frontal mirror. The resultant magnification provides for a better diagnosis of laryngeal disorders. The recording of the image on a stroboscopic VCR offers numerous possibilities, such as freeze-frame, zoom, slow motion, 9 or 16 image framing, showing the various positions of the vocal cords. The use of this video technique is of particular interest for the patient and for the practitioner, as well as for reference. 相似文献
16.
The types of drugs used by HIV-infected injection drug users in a multistate surveillance project: implications for intervention. 总被引:2,自引:0,他引:2
下载免费PDF全文
![点击此处可从《American journal of public health》网站下载免费的PDF全文](/ch/ext_images/free.gif)
T Diaz S Y Chu R H Byers Jr B S Hersh L Conti C A Rietmeijer E Mokotoff S A Fann D Boyd L Iglesias et al. 《American journal of public health》1994,84(12):1971-1975
OBJECTIVES. This study sought to describe the drugs used by drug injectors infected with human immunodeficiency virus (HIV) and to determine factors associated with the primary injection drug used. METHODS. A cross-section of persons 18 years of age or older reported with HIV or acquired immunodeficiency syndrome (AIDS) to local health departments in 11 US states and cities was surveyed. RESULTS. Of 4162 persons interviewed, 1147 (28%) reported ever having injected drugs. Of these 1147 injectors, 72% primarily injected a drug other than heroin. However, the types of drugs injected varied notably by place of residence. Heroin was the most commonly injected drug in Detroit (94%) and Connecticut (48%); cocaine was the most common in South Carolina (64%), Atlanta (56%), Delaware (55%), Denver (46%), and Arizona (44%); speedball was most common in Florida (46%); and amphetamines were most common in Washington (56%). Other determinants of the type of drug primarily injected were often similar by region of residence, except for heroin use. Polysubstance abuse was common; 75% injected more than one type of drug, and 85% reported noninjected drug use. CONCLUSIONS. Preventing the further spread of HIV will require more drug abuse treatment programs that go beyond methadone, address polysubstance abuse, and adapt to local correlates of the primary drug used. 相似文献
17.
IMPT1, an imprinted gene similar to polyspecific transporter and multi- drug resistance genes 总被引:5,自引:1,他引:5
Dao D; Frank D; Qian N; O'Keefe D; Vosatka RJ; Walsh CP; Tycko B 《Human molecular genetics》1998,7(4):597-608
Human chromosome 11p15.5 and distal mouse chromosome 7 include a
megabase-scale chromosomal domain with multiple genes subject to parental
imprinting. Here we describe mouse and human versions of a novel imprinted
gene, IMPT1 , which lies between IPL and p57 KIP2 and which encodes a
predicted multi-membrane-spanning protein similar to bacterial and
eukaryotic polyspecific metabolite transporter and multi- drug resistance
pumps. Mouse Impt1 and human IMPT1 mRNAs are highly expressed in tissues
with metabolite transport functions, including liver, kidney, intestine,
extra-embryonic membranes and placenta, and there is strongly preferential
expression of the maternal allele in various mouse tissues at fetal stages.
In post-natal tissues there is persistent expression, but the allelic bias
attenuates. An allelic expression bias is also observed in human fetal and
post-natal tissues, but there is significant interindividual variation and
rare somatic allele switching. The fact that Impt1 is relatively repressed
on the paternal allele, together with data from other imprinted genes,
allows a statistical conclusion that the primary effect of human chromosome
11p15.5/mouse distal chromosome 7 imprinting is domain-wide relative
repression of genes on the paternal homolog. Dosage regulation of the
metabolite transporter gene(s) by imprinting might regulate placental and
fetal growth.
相似文献
18.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
19.
Characterization of a gene encoding survival motor neuron (SMN)-related protein, a constituent of the spliceosome complex 总被引:2,自引:3,他引:2
Talbot K; Miguel-Aliaga I; Mohaghegh P; Ponting CP; Davies KE 《Human molecular genetics》1998,7(13):2149-2156
Mutations in the gene encoding the Survival Motor Neuron (SMN) protein are
responsible for autosomal recessive proximal spinal muscular atrophy (SMA).
SMN orthologues have been identified in the nematode worm Caenorhabditis
elegans and the yeast Schizosaccharomyces pombe but, to date, no human
paralogues have been described. Here we describe identification and
characterization of an SMN-related protein (SMNrp) gene that encodes a
novel protein of 239 amino acids, which has recently been identified as a
constituent of the spliceosome complex and designated SPF30. Significant
similarity to the SMN protein is apparent only within a central region of
SMNrp that represents a tudor domain. The SMNrp/SPF30 gene has been mapped
to chromosome 10q23. It is differentially expressed, with abundant levels
in skeletal muscle. An exclusively nuclear localization for SMNrp in
cultured cells and muscle sections was revealed using GFP fusion constructs
and thereafter confirmed with a polyclonal antibody raised against SMNrp.
Overexpression of SMNrp as a fusion protein in HeLa cells in culture
induced dose-dependent apoptosis with positive TUNEL staining. In addition
to a possible role for this protein as a pro-apoptotic factor, SMN and its
related protein share significant similarities in sequence and cellular
function.
相似文献
20.
CP Schaecher KA Groesch 《American journal of reproductive immunology (New York, N.Y. : 1989)》2006,55(6):405-405
Background: Control of mRNA stability is an essential regulatory process in eukaryotic gene expression. HuR, a 3'UTR mRNA binding protein, can protect AU-rich mRNA from degradation in response to stresses. PlGF, an angiogenic growth factor, contains two consensus AU-rich sites suggesting that under normal conditions HuR may protect PlGF mRNA from degradation. Trophoblast expression of PlGF is significantly decreased in preeclampsia and by hypoxia in vitro . We hypothesize that decreased levels of cytoplasmic HuR may contribute to decreased PlGF expression in hypoxic and preeclamptic trophoblast.
Methods: Western blots were used to determine relative effects of in vitro hypoxia on HuR protein expression and subcellular localization in trophoblast. Immunohistochemistry was used to compare HuR expression patterns in trophoblast of preeclamptic and normal placentae.
Results: Cytoplasmic expression of HuR was decreased 1.4 fold in the cytoplasm and 1.2 fold in the nucleus of JEG3 cells. A shift in HuR was more apparent in primary trophoblast with a greater than 2-fold decrease in the cytoplasm and a 1.4 fold decrease in the nucleus following 24 hr of hypoxia. Immunohistochemical analyses detected HuR expression in near term trophoblast in situ . However, this technical approach did not detect a significant change in HuR expression between normal and preeclamptic trophoblast.
Conclusions: HuR expression is decreased in hypoxic trophoblast, at least in vitro , which may provide a causal link to decreased PlGF mRNA expression. Down regulation of trophoblast PlGF expression is thought to contribute to the pathophysiology associated with preeclampsia including the relative lack of perfusion of the placenta and systemic renal effects. 相似文献
Methods: Western blots were used to determine relative effects of in vitro hypoxia on HuR protein expression and subcellular localization in trophoblast. Immunohistochemistry was used to compare HuR expression patterns in trophoblast of preeclamptic and normal placentae.
Results: Cytoplasmic expression of HuR was decreased 1.4 fold in the cytoplasm and 1.2 fold in the nucleus of JEG3 cells. A shift in HuR was more apparent in primary trophoblast with a greater than 2-fold decrease in the cytoplasm and a 1.4 fold decrease in the nucleus following 24 hr of hypoxia. Immunohistochemical analyses detected HuR expression in near term trophoblast in situ . However, this technical approach did not detect a significant change in HuR expression between normal and preeclamptic trophoblast.
Conclusions: HuR expression is decreased in hypoxic trophoblast, at least in vitro , which may provide a causal link to decreased PlGF mRNA expression. Down regulation of trophoblast PlGF expression is thought to contribute to the pathophysiology associated with preeclampsia including the relative lack of perfusion of the placenta and systemic renal effects. 相似文献