全文获取类型
收费全文 | 2373篇 |
免费 | 151篇 |
国内免费 | 84篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 42篇 |
妇产科学 | 75篇 |
基础医学 | 446篇 |
口腔科学 | 18篇 |
临床医学 | 263篇 |
内科学 | 459篇 |
皮肤病学 | 68篇 |
神经病学 | 124篇 |
特种医学 | 229篇 |
外科学 | 301篇 |
综合类 | 35篇 |
预防医学 | 117篇 |
眼科学 | 44篇 |
药学 | 184篇 |
中国医学 | 7篇 |
肿瘤学 | 182篇 |
出版年
2023年 | 4篇 |
2022年 | 40篇 |
2021年 | 61篇 |
2020年 | 32篇 |
2019年 | 35篇 |
2018年 | 65篇 |
2017年 | 45篇 |
2016年 | 78篇 |
2015年 | 90篇 |
2014年 | 111篇 |
2013年 | 140篇 |
2012年 | 181篇 |
2011年 | 183篇 |
2010年 | 115篇 |
2009年 | 98篇 |
2008年 | 141篇 |
2007年 | 161篇 |
2006年 | 112篇 |
2005年 | 134篇 |
2004年 | 98篇 |
2003年 | 88篇 |
2002年 | 81篇 |
2001年 | 95篇 |
2000年 | 83篇 |
1999年 | 50篇 |
1998年 | 33篇 |
1997年 | 40篇 |
1996年 | 14篇 |
1995年 | 18篇 |
1994年 | 19篇 |
1993年 | 15篇 |
1992年 | 24篇 |
1991年 | 19篇 |
1990年 | 16篇 |
1989年 | 17篇 |
1988年 | 11篇 |
1987年 | 10篇 |
1986年 | 5篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1976年 | 6篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1925年 | 1篇 |
排序方式: 共有2608条查询结果,搜索用时 93 毫秒
11.
OBJECTIVE: To determine the effectiveness of Neodymium-YAG (Nd-YAG) laser for hysteroscopic transection of the septate uterus to improve pregnancy outcome. DESIGN: Patients treated for recurrent pregnancy loss and/or infertility were evaluated for before versus after treatment pregnancy outcomes. SETTING: All patients were referred to a University Reproductive Endocrine and Infertility practice from 1986 through 1990. PATIENTS, PARTICIPANTS: Nineteen patients underwent hysteroscopic transection of uterine septa after exclusion of other factors that may cause recurrent fetal wastages and/or infertility. They were allowed to conceive 8 weeks after surgery after a postoperative hysterosalpingogram. Fourteen women attempted conception during a time span of 11 to 42 months; 3 patients declined to conceive, and 2 were lost to follow-up. INTERVENTIONS: Hysteroscopic transection of the uterine septum with a Nd-YAG laser was performed in all patients. The Nd-YAG laser delivered via a 600-microns bare fiber or an 800-microns sculpted fiber through operative hysteroscopy. MAIN OUTCOME MEASURES: To evaluate the success and complications of this new laser technique. RESULTS: (1) Thirteen patients conceived; 10 delivered a live infant at term; (2) 87% of the postoperative pregnancies were considered successful as compared with 11% preoperative; (3) complications included a small perforation of the uterus (no treatment needed) and development of uterine adhesions (1 case only). CONCLUSIONS: Hysteroscopic metroplasty with the Nd-YAG laser is a valuable alternative new technique for the treatment of uterine septum. 相似文献
12.
LEE JS IM HH JUNG Y JUNG IS JANG JY CHUN YK CHO YD KIM JO CHO JY KIM YS SHIM CS & KIM BS 《Neurogastroenterology and motility》2006,18(6):493-494
Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future. 相似文献
13.
14.
This study was designed to demonstrate that differentiation of stomach cancer cells can be modified by microenvironmental change and to look for a method inducing or promoting tumor cell differentiation. To evaluate the biomorphological characterization of tumor cell differentiation in suramin-containing in vitro culture of human stomach cancer cell lines, inverted phase-contrast microscopic examination, analysis of growth curves and BrdU-positive S-phase fraction, immunocytochemical study, radioimmunoassay for CEA, transmission electron microscopic examination, DNA flow cytometry, and heterotransplantation in SCID mice were performed. Suramin inhibited tumor cell growth. Development of intracytoplasmic lumina and intercellular lumina was noted in suramin-containing culture with formation of numerous microvilli and frequent desmosomes. The amount of CEA released by a cell was increased in suramin-containing culture. Suramin inhibited heterotransplantation, and a transplant from suramin-containing culture revealed a much higher degree of differentiation than that from suramin-absent culture. Suramin induced no change in DNA ploidy pattern. Elimination of suramin from the culture medium did not reverse the tumor cell differentiation. Each stomach cancer cell line showed a different degree of responsiveness to suramin. In conclusion, this study shows that suramin inhibits growth of SNU-5 and SNU-16 cells and that suramin induces differentiation of SNU-16 cells. 相似文献
15.
对10名男性受试者单剂量po240mgVer缓释片药代动力学及心电图变化进行研究。血药浓度—时间数据用零级吸收过程的一室模型拟合,其药代动力学参数:Tmax5.9±1.6h;Cmax118.9±37.2μg·L-1;T1 5.4±1.5h;k030.5±17.5μg·L-1·h-1;T1/210.8±4.9h。PR间期延长有显著意义,血药浓度与PR间期变化满足S 型模型,其药效学参数:EC50 64.6±16.9μg·L-1; Emax54±11ms;s 1.68±0.66。 相似文献
16.
17.
Hydrolysis of peptides within lumen of small intestine 总被引:2,自引:0,他引:2
18.
S. C. Park W. H. Kim M. C. Lee S. C. Seong K. Y. Song M. A. Choe 《Journal of Korean medical science》1994,9(6):490-496
The persistence of muscle fiber number regardless of size reduction in muscle atrophy has not yet been fully explained. For the mechanism inherent in skeletal muscle tissues for preventing cellular death, the protective function of muscle tissue through transglutaminases has been tested, since the enzyme is responsible for structural stabilization and participates in signal transduction. In the present experiment, hindlimb suspension for two weeks caused a marked muscle atrophy in Wistar female rats. Comparison of muscle weight and histological analysis showed that suspension-induced atrophy in the hindlimb was more prominent in the soleus muscle, comprised mainly of type I fiber than that in the plantaris muscle of type II fibers. The immunohistochemical analysis with antitransglutaminase C antibody (anti TGase C Ab) showed that some atrophic bundles of soleus muscle were positively reacted with the antibody. The anti-TGase C Ab-reactive substances were observed to disappear significantly after endurance exercise, indicating their characteristic atrophy-dependency. The enzymatic analysis of transglutaminase showed the increase in activity in the atrophic soleus muscle tissue, compared with that in the normal or exercise-trained muscle tissues. From these results, the expression of TGase in the atrophic muscle is suggested to be the possible marker for muscle atrophy and its expression is probably related with the protective mechanism of the muscle tissue to prevent further cellular damage in the atrophic process. 相似文献
19.
Burwinkel B; Maichele AJ; Aagenaes O; Bakker HD; Lerner A; Shin YS; Strachan JA; Kilimann MW 《Human molecular genetics》1997,6(7):1109-1115
Glycogen storage disease due to phosphorylase kinase deficiency occurs in
several variants that differ in mode of inheritance and tissue-
specificity. This heterogeneity is suspected to be largely due to mutations
affecting different subunits and isoforms of phosphorylase kinase. The gene
of the ubiquitously expressed beta subunit, PHKB, was a candidate for
involvement in autosomally transmitted phosphorylase kinase deficiency of
liver and muscle. To identify such mutations, the complete PHKB coding
sequence was amplified by RT-PCR of RNA isolated from blood samples of
patients and analyzed by direct sequencing of PCR products. The
characterization of mutations was complemented by PCR of genomic DNA. In
one female and four male patients, we identified five independent nonsense
mutations (Y418ter; R428ter; Y974H+E975ter; Q656ter in two cases), one
single-base insertion in codon N421, one splice-site mutation affecting
exon 31, and a large deletion involving the loss of exon 8. Although these
severe translation-disrupting mutations occur in constitutively expressed
sequences of the only known beta subunit gene of phosphorylase kinase,
PHKB, they are associated with a surprisingly mild clinical phenotype,
affecting virtually only the liver, and relatively high residual enzyme
activity of approximately 10%.
相似文献
20.
This study was designed to determine whether the somatostatin analogue,
octreotide, could prevent embryonic loss by normalizing increased uterine
insulin-like growth factor-I (IGF-I) action related to hyperoestrogenaemia
following superovulation. Superovulated immature and
oestradiol-17beta-treated adult rats were infused with 100 or 300 microg/ml
of octreotide respectively, or injected daily with 1 or 10 microg of
octreotide from day 1 to day 3 of pregnancy. On day 3, embryos were
collected from the oviducts and uteri. Uterine luminal fluid was subjected
to embryo culture. The amounts of uterine IGF-I and IGF binding proteins
(IGFBP) were determined by radioimmunoassay and ligand binding assay
respectively. Octreotide infusion normalized uterine IGF-I action following
superovulatory and oestradiol-17beta treatment, by reducing IGF-I
concentrations and increasing IGFBP concentrations. Octreotide infusion
increased the number of normal embryos by 2.7-fold and 1.7-fold in
superovulated and oestradiol-17beta- treated rats respectively, and
reversed the detrimental effects of uterine luminal fluid on embryonic
development caused by superovulatory and oestradiol-17beta treatment. Daily
injections with octreotide had similar but reduced effects in all
parameters examined in both treatment groups. In conclusion, octreotide may
reduce embryonic loss, at least in part, by normalizing IGF-I action
following superovulation.
相似文献