全文获取类型
收费全文 | 727篇 |
免费 | 24篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 24篇 |
妇产科学 | 17篇 |
基础医学 | 94篇 |
口腔科学 | 21篇 |
临床医学 | 46篇 |
内科学 | 155篇 |
皮肤病学 | 14篇 |
神经病学 | 45篇 |
特种医学 | 10篇 |
外科学 | 236篇 |
综合类 | 12篇 |
预防医学 | 13篇 |
眼科学 | 3篇 |
药学 | 51篇 |
中国医学 | 1篇 |
肿瘤学 | 21篇 |
出版年
2021年 | 4篇 |
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 13篇 |
2017年 | 9篇 |
2016年 | 10篇 |
2015年 | 8篇 |
2014年 | 20篇 |
2013年 | 36篇 |
2012年 | 46篇 |
2011年 | 59篇 |
2010年 | 43篇 |
2009年 | 41篇 |
2008年 | 70篇 |
2007年 | 47篇 |
2006年 | 47篇 |
2005年 | 39篇 |
2004年 | 26篇 |
2003年 | 14篇 |
2002年 | 19篇 |
2001年 | 7篇 |
2000年 | 4篇 |
1999年 | 5篇 |
1998年 | 8篇 |
1997年 | 12篇 |
1996年 | 11篇 |
1995年 | 9篇 |
1994年 | 6篇 |
1993年 | 11篇 |
1992年 | 6篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 9篇 |
1988年 | 12篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 6篇 |
1978年 | 7篇 |
1976年 | 8篇 |
1973年 | 3篇 |
1972年 | 3篇 |
1971年 | 3篇 |
1967年 | 3篇 |
1965年 | 3篇 |
排序方式: 共有765条查询结果,搜索用时 125 毫秒
1.
Transfer of clonidine and dexmedetomidine across the isolated perfused human placenta 总被引:4,自引:0,他引:4
T. I. ALA-KOKKO P. PIENIMÄKI E. LAMPELA A. I. HOLLMÉN O. PELKONEN K. VÄHÄKANGAS 《Acta anaesthesiologica Scandinavica》1997,41(2):313-319
Background: The placental transfer of the a2 receptor agonist clonidine, earlier used as an adjuvant in obstetric epidural analgesia, was compared with the transfer of the newer and more %-selective agonist dexmedetomidine.
Methods: Term placentas were obtained immediately after delivery with maternal consent and a 2-hour recycling perfusion of a single placental cotyledon was performed. Disappearance from the maternal circulation, accumulation in placental tissue and appearance in the fetal circulation of clonidine or dexmedetomidine with the reference compound antipyrine were followed in 4 experiments for both drugs.
Results: At 2 hours the percent dexmedetomidine found in the fetal circulation was 12.5 (SD 5.1)%, while 48.1 (SD 20.3)% was found in the perfused placental cotyledon. A higher mean clonidine than dexmedetomidine concentration was achieved in the fetal circulation (1.90 vs. 0.56 nmol/l, P <0.05). At 2 hours the percent clonidine found in the fetal circulation was 22.1 (SD 2.4)% ( P <0.05), while 11.3 (SD 3.3)% ( P <0.05) was re tained in the perfused placental cotyledon. The transfer indexes, describing maternal-to-fetal transfer of dexmedetomidine and clonidine normalized with the transfer of antipyrine, were 0.88 (SD 0.07) and 1.04 (SD 0.08) respectively ( P <0.05).
Conclusions: Dexmedetomidine disappeared faster than clonidine from the maternal circulation, while even less dexmedetomidine was transported into the fetal circulation. This was due to its greater placental tissue retention, the basis for which probably is the higher lipophilicity of dexmedetomidine. 相似文献
Methods: Term placentas were obtained immediately after delivery with maternal consent and a 2-hour recycling perfusion of a single placental cotyledon was performed. Disappearance from the maternal circulation, accumulation in placental tissue and appearance in the fetal circulation of clonidine or dexmedetomidine with the reference compound antipyrine were followed in 4 experiments for both drugs.
Results: At 2 hours the percent dexmedetomidine found in the fetal circulation was 12.5 (SD 5.1)%, while 48.1 (SD 20.3)% was found in the perfused placental cotyledon. A higher mean clonidine than dexmedetomidine concentration was achieved in the fetal circulation (1.90 vs. 0.56 nmol/l, P <0.05). At 2 hours the percent clonidine found in the fetal circulation was 22.1 (SD 2.4)% ( P <0.05), while 11.3 (SD 3.3)% ( P <0.05) was re tained in the perfused placental cotyledon. The transfer indexes, describing maternal-to-fetal transfer of dexmedetomidine and clonidine normalized with the transfer of antipyrine, were 0.88 (SD 0.07) and 1.04 (SD 0.08) respectively ( P <0.05).
Conclusions: Dexmedetomidine disappeared faster than clonidine from the maternal circulation, while even less dexmedetomidine was transported into the fetal circulation. This was due to its greater placental tissue retention, the basis for which probably is the higher lipophilicity of dexmedetomidine. 相似文献
2.
3.
G. Paraskevas B. Papaziogas C. Lazaridis P. Gigis T. Papaziogas 《Surgical and radiologic anatomy : SRA》2002,23(6):437-442
Abstract: Three cases (two male, one female) of annular pancreas are presented, which were found and operated on within the last three decades. Diagnosis was made using imaging techniques, especially ultrasonography and computed tomography. In two cases there was incomplete obstruction, while in the other obstruction was complete. It is characteristic that in the case of complete obstruction the annular portion of the pancreas attached to a circular band of connective tissue, while in the two cases of incomplete obstruction there was a complete ring of pancreatic tissue. In all cases surgical intervention was needed in order to create a bypass. In the first case gastroenterostomy and truncal vagotomy was performed, in the second latero-lateral duodeno-jejunostomy and in the third latero-lateral antropyloroduodeno-jejunostomy. The embryology and morphology of the annular pancreas, the morphology of its duct system, diagnosis, differential diagnosis and the surgical treatment of this rare condition are reviewed. 相似文献
4.
Density of γ/δ+ T cells in the jejunal epithelium of patients with coeliac disease and dermatitis herpetiformis is increased with age
下载免费PDF全文
![点击此处可从《Clinical and experimental immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
E SAVILAHTI T
RML A ARATO G HACSEK K HOLM T KLEMOLA A NEMETH M MKI T REUNALA 《Clinical and experimental immunology》1997,109(3):464-467
Increased density of γ/δ T cell receptor (TCR)+ intraepithelial lymphocytes is the only characteristic in the jejunum of patients with coeliac disease and dermatitis herpetiformis which is not normalized on a gluten-free diet. We explored the age-dependent changes in intraepithelial γ/δ and α/β TCR+ cells from 137 biopsies from patients with coeliac disease and dermatitis herpetiformis and from controls. Biopsy specimens from 100 patients with coeliac disease and dermatitis herpetiformis and from 37 controls were studied with an immunohistochemical method using MoAbs to T cell receptors and peroxidase staining. An increase in the density of intraepithelial γ/δ T cells above the mean +2 s.d. of the density in controls was present in 97 of 100 specimens from patients with coeliac disease and dermatitis herpetiformis. The density of γ/δ+ cells of patients with coeliac disease and dermatitis herpetiformis on a normal gluten-containing diet showed a positive correlation with age (r = 0.45, P< 0.0001). In controls, the density of γ/δ+ cells remained low throughout the age-range studies, from age 0.6–57 years. In controls, α/β+ cells increased with age (r = 0.57, P< 0.001). The increase in density of intraepithelial lymphocytes with age is in agreement with their thymus-independent character and local proliferation. 相似文献
5.
In an effort to assess the effect of ambient temperature on the gross efficiency (Effg) of step exercise 12 subjects performed a modified step test either at —15 °C or 21°C ascending to three different heights (corresponding to light, moderate and heavy work), for 20 min each with a frequency of 18 steps min-1. Heart rate (HR), rectal temperature, skin temperatures and heat flux from skin were continuously measured. Oxygen consumption was measured during the last 5 min of each step height and perceptions of thermal sensation were recorded. The results indicate that, while using conventional clothing adequate in these temperatures, Effg is altered in a contradictory manner. At —15°C Effg increased with increasing work load, whereas at 21°C it decreased when the work load increased. The highest Effg (heavy work at —15°C and light work at 21°C) values are reflected as rather similar rectal temperatures (37.4–37.7°C) and identical mean skin temperatures (32.8 °C) as well as the same (slightly warm) thermal sensation of the legs. At — 15 °C the lowest Effg in light work was probably hue to the need to warm up the muscles. At 21°C, on the contrary, the activation of heat dissipation systems was probably responsible for the lowest Effg in heavy work. 相似文献
6.
Wollmer MA Papassotiropoulos A Streffer JR Grimaldi LM Kapaki E Salani G Paraskevas GP Maddalena A de Quervain D Bieber C Umbricht D Lemke U Bosshardt S Degonda N Henke K Hegi T Jung HH Pasch T Hock C Nitsch RM 《Psychiatric genetics》2002,12(3):155-160
Tissue inhibitor of metalloproteinases 1 (TIMP-1) inhibits several proteinases including a disintegrin and metalloproteinase 10 (ADAM10), a major alpha-secretase that cleaves the beta-amyloid precursor protein within its amyloidogenic Abeta domain. The gene encoding TIMP-1 (TIMP 1) maps to the short arm of the X chromosome, in a region previously suggested as conferring genetic susceptibility for Alzheimer's disease (AD). To determine whether genetic variability of TIMP 1 contributes to the pathogenesis of AD, we analysed one single nucleotide polymorphism within TIMP 1 and one single nucleotide polymorphism in the 5'-untranslated region of TIMP 1 in patients with AD and control subjects from two independent and ethnically different populations. We did not observe any association between TIMP 1 genotypes and the diagnosis of AD in men or women. We also measured TIMP-1 protein levels in the cerebrospinal fluid of patients with AD, healthy control subjects, and patients with other neurological disorders. TIMP-1 levels were similar in all groups. In addition, no significant differences were observed after stratification for TIMP 1 genotypes. Our data show that neither genetic variability nor protein levels of TIMP-1 are associated with AD. 相似文献
7.
Study of the carrying angle of the human elbow joint in full extension: a morphometric analysis 总被引:3,自引:0,他引:3
Paraskevas G Papadopoulos A Papaziogas B Spanidou S Argiriadou H Gigis J 《Surgical and radiologic anatomy : SRA》2004,26(1):19-23
This study measured the carrying angle of the elbow joint in full extension in 600 students, using the supplementary angle to that between the longitudinal axis of the arm and that of the forearm. The mean carrying angle was 12.88°±5.92: 10.97°±4.27 in men and 15.07°±4.95 in women. The carrying angle changes with skeletal growth and maturity. The angle is always greater on the side of the dominant hand. We confirmed the inverse relationship between the carrying angle and the intertrochanteric diameter. Also, the type of constitution influences the value of the carrying angle, especially in women. 相似文献
8.
P.
Kp T. JAHNUKAINEN J.
GR
NLUND M.
RAUTANEN L.
HALKOLA I.
VLIMKI 《Acta physiologica (Oxford, England)》1997,160(3):283-289
To investigate the pulmonary haemodynamic effects of meconium aspiration and subsequent adenosine triphosphate (ATP) treatment, 12 anaesthetized and ventilated pigs (wt 24-28 kg) received either ATP or an equal volume of saline into the right heart in doses of 0.02 to 0.80 lmol kg-1 min?1 after intratracheal administration of 2 mL kg?1 of human meconium. Meconium instillation induced significant increases in pulmonary vascular pressures and total and postarterial resistances calculated from pulmonary artery occlusion studies, but did not affect the systemic haemodynamics, except for a fall in heart rate and increase in central venous pressure. Infusion of ATP at the lowest doses (0.02 and 0.08 µmol kg?1 min?1) selectively decreased the pulmonary arterial pressure and vascular resistance and at 0.32 and 0.80 µmol kg?1 min?1 reduced both the pulmonary and systemic resistances. In the lung circulation the increasing doses of ATP reduced preferably the arterial, but also the postarterial resistance. Withdrawal of ATP infusion led to a significant rebound effect especially in the postarterial segment of the lung circulation. Meconium aspiration thus induces an acute, predominantly postarterial obstruction in the lung circulation and infusion of ATP at low doses selectively dilates the pulmonary vascular bed and may help to preclude elevation of capillary pressures in meconium aspiration-induced pulmonary hypertension. 相似文献
9.
Paraskevas G Papaziogas B Lazaridis C Gigis P Papaziogas T 《Surgical and radiologic anatomy : SRA》2001,23(6):437-442
Three cases (two male, one female) of annular pancreas are presented, which were found and operated on within the last three decades. Diagnosis was made using imaging techniques, especially ultrasonography and computed tomography. In two cases there was incomplete obstruction, while in the other obstruction was complete. It is characteristic that in the case of complete obstruction the annular portion of the pancreas attached to a circular band of connective tissue, while in the two cases of incomplete obstruction there was a complete ring of pancreatic tissue. In all cases surgical intervention was needed in order to create a bypass. In the first case gastroenterostomy and truncal vagotomy was performed, in the second latero-lateral duodeno-jejunostomy and in the third latero-lateral antropyloroduodeno-jejunostomy. The embryology and morphology of the annular pancreas, the morphology of its duct system, diagnosis, differential diagnosis and the surgical treatment of this rare condition are reviewed. 相似文献
10.