全文获取类型
收费全文 | 13351篇 |
免费 | 957篇 |
国内免费 | 19篇 |
学科分类
医药卫生 | 14327篇 |
出版年
2023年 | 94篇 |
2022年 | 95篇 |
2021年 | 173篇 |
2020年 | 173篇 |
2019年 | 239篇 |
2018年 | 236篇 |
2017年 | 215篇 |
2016年 | 241篇 |
2015年 | 255篇 |
2014年 | 301篇 |
2013年 | 471篇 |
2012年 | 582篇 |
2011年 | 605篇 |
2010年 | 368篇 |
2009年 | 361篇 |
2008年 | 634篇 |
2007年 | 538篇 |
2006年 | 565篇 |
2005年 | 582篇 |
2004年 | 517篇 |
2003年 | 473篇 |
2002年 | 429篇 |
2001年 | 476篇 |
2000年 | 410篇 |
1999年 | 364篇 |
1998年 | 142篇 |
1997年 | 110篇 |
1996年 | 127篇 |
1995年 | 118篇 |
1994年 | 113篇 |
1993年 | 111篇 |
1992年 | 270篇 |
1991年 | 295篇 |
1990年 | 318篇 |
1989年 | 316篇 |
1988年 | 229篇 |
1987年 | 252篇 |
1986年 | 247篇 |
1985年 | 241篇 |
1984年 | 177篇 |
1983年 | 170篇 |
1982年 | 118篇 |
1980年 | 82篇 |
1979年 | 167篇 |
1978年 | 113篇 |
1977年 | 94篇 |
1975年 | 94篇 |
1974年 | 106篇 |
1973年 | 96篇 |
1971年 | 81篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
The effect of bone drilling on pain in gonarthrosis 总被引:1,自引:0,他引:1
Summary Seventy-seven patients with mild to moderate gonarthrosis of the knee were treated by subchondral bone drilling, and followed for from 2 to 7 years. Patients with generalised arthrosis benefited more than those with unicompartmental involvement. Pain, assessed by a visual analogue scale, was significantly reduced compared with a control group of 16 patients who had a diagnostic arthroscopy only. Drilling is a safe procedure with few complications and can be used in patients when more extensive surgery is not yet indicated or possible.
Résumé Vingt-sept cas d'arthrose légère ou modérée du genou, diagnostiqués par arthroscopie et traités par forage, ont été revus avec un recul moyen de 4 ans (de 2 à 7 ans). La douleur, évaluée selon la cotation VAS, était diminuée pendant 24 mois en moyenne (1 à 76) dans les deux tiers des cas. Les résultats étaient meilleurs chez les patients présentant une arthrose globale que chez ceux atteints d'une arthrose uni-compartimentale. Ils étaient obtenus aussi bien dans les cas douloureux au repos (n=39) que dans ceux douloureux lors de la mobilisation du genou (n=14). Les complications ont été exceptionnelles (n=1). La douleur était diminuée dans une proportion significativement supérieure dans les genoux traités par forage que dans un groupe de contrôle de 16 cas, n'ayant subi qu'une arthroscopie à visée diagnostique (p=0.006). Le forage est un procédé sûr, n'entraînant que de rares complications. Il est indiqué dans le traitement des douleurs du genou chez les patients ayant une arthrose légère ou modérée, lorsque des interventions plus importantes ne sont ni nécessaires, ni réalisables.相似文献
12.
T. Scholz Ø. Mathisen A. Bergan S. Osnes R. Innes T. Pedersen A. O. Aasen O. Søreide 《Transplant international》1997,10(3):180-184
We have introduced and evaluated several modifications of the conventional venovenous bypass (VVBP) in 29 adult patients
undergoing liver transplantation (OLT). A percutaneous technique for insertion of a jugular venous return cannula and a femoral
vein cannula was applied. The inferior mesenteric vein (IMV) was used for splanchnic decompression, which facilitated dissection
of the recipient liver and allowed portal anastomosis to be performed without disconnecting the portal bypass. A heat exchanger
was introduced into the bypass circuit to prevent heat loss. The percutaneous technique prevented complications related to
dissection in the axilla and groin. Hemodynamic characteristics corresponded to those found using the traditional technique.
Complications related to the VVBP were seen in only one patient in whom the femoral catheter was accidentally introduced into
the femoral artery. We conclude that percutaneous cannulas, use of the IMV for splanchnic decompression and the introduction
of a heat exchanger offer significant benefits and that they are safe and reliable.
Received: 23 August 1996 Received after revision: 14 January 1997 Accepted: 27 January 1997 相似文献
13.
MR imaging was reviewed in 66 pediatric spinal cord patients with diagnoses of posterior fossa tumor (n = 8), primary spinal cord tumor (n = 3), metastatic disease (n = 11), neuroectodermal disorder (n = 8), congenital malformation (n = 14), trauma (n = 2), and demyelinating, neurodegenerative, or metabolic disorders (n = 9). MR proved to be useful in delineating the extent of posterior fossa and cord tumor including metastasis to the cord. MR was of limited value in demyelinating and metabolic disorders. Arnold Chiari malformations, syringomyelia, tethered cord and meningoceles were all easily evaluated using MR. 相似文献
14.
Blood volume, blood pressure, plasma concentrations of atrial natriuretic peptide (ANP), cyclic 3',5'-guanosine monophosphate (cGMP), angiotensin II, aldosterone, and arginine vasopressin (AVP), and urinary excretion rates of cGMP, sodium, and water were determined before and after infusion of human albumin 20%, 3.5 ml/kg body-weight to 12 patients with chronic glomerulonephritis and 19 healthy control subjects (Study 1); and before and after frusemide injection, 0.75 mg/kg to 15 patients with chronic glomerulonephritis and 19 healthy control subjects (Study 2). In Study 1 blood volume was expanded to the same degree in patients (8.8 and 7.5%, medians, after 90 and 180 min) and controls (8.6 and 6.1%). ANP was enhanced in the patients (5.9 to 11.0 pmol/l, P less than 0.01) and the controls (4.9 to 7.1 pmol/l, P less than 0.01), but the elevated level was protracted in the patients simultaneously with a delayed sodium excretion. Plasma cGMP increased, aldosterone decreased and AVP was unchanged in both groups, whereas angiotensin II decreased in the patients (P less than 0.01), but not in the controls. In Study 2 blood volume was reduced to a smaller extent in the patients than in the controls (8.9% versus 9.9%, P less than 0.05). ANP an cGMP decreased, and angiotensin II, aldosterone and AVP increased in both patients and controls. In conclusion, patients with glomerulonephritis respond to albumin- and frusemide induced changes in blood volume with essentially the same counter-regulatory changes in ANP, angiotensin II, aldosterone and AVP as do healthy subjects. The more protracted increase in ANP and the decrease in angiotensin II after albumin, and the smaller blood volume reduction after frusemide suggest an abnormal regulation of blood volume in glomerulonephritis. 相似文献
15.
16.
E K Lund W E Lee-Finglas S Southon J M Gee I T Johnson P M Finglas A J Wright 《European journal of clinical nutrition》1992,46(12):857-864
The relationship between dietary fat intake and fasting plasma lipid levels was assessed in 35 female and 19 male adolescents recruited from two local education authority schools in Norwich, UK. Dietary intakes were assessed using a 7-day weighed dietary record method, coupled with the collection of duplicate diets. Fat and energy intakes calculated using food composition tables were compared with values obtained by direct analysis of duplicate diets. Fasting plasma lipid levels (total, HDL and LDL cholesterol and triglycerides) were measured and compared with total dietary lipids and fatty acid intakes. The average proportion of energy consumed as fat was higher than is currently considered desirable but lower than previous studies have reported for adults. Mean serum total cholesterol values were 4.2 (SEM 0.1) mmol for females and 4.5 (SEM 0.2) mmol for males; this difference was not statistically significant. In male subjects the dietary fatty acid profiles were significantly correlated with several parameters of plasma lipid status which are thought to be risk factors for coronary heart disease, and in particular with the ratio of total:HDL cholesterol. 相似文献
17.
M J Buxton S D Sullivan L F Andersson C J Lamm B Liljas W W Busse S Pedersen K B Weiss 《The European respiratory journal》2004,24(4):568-574
Early intervention with budesonide is an effective strategy for mild persistent asthma, which has been shown to provide additional clinical benefits at a low incremental cost using USA cost data. The present authors analysed whether this strategy would be cost-effective using cost data for other countries. Based on the 3-yr prospective, randomised, double-blind inhaled Steroid Treatment As Regular Therapy (START) in early asthma study (comparing budesonide and placebo combined with usual asthma therapy), the cost-effectiveness was estimated separately for eight different countries, from both healthcare payer and societal perspectives, of adding budesonide to usual asthma therapy. Local unit costs were applied to data for the total trial population. Incremental cost-effectiveness ratios (ICER) were estimated as cost per symptom-free day (SFD) gained. Budesonide increased SFDs by an average of 14.1 days annually. From a healthcare payer perspective, budesonide would reduce the total cost of asthma care in Australia. In Sweden, Canada, France, Spain, UK, China and the USA, the ICER ranged from US$2.4-11.3 per SFD. From a societal perspective, budesonide would be cost-saving in Australia, Canada and Sweden. In conclusion, for countries where costs with budesonide are higher, the policy implication has to be determined by that health system's willingness to pay for an additional symptom-free day. However, where budesonide therapy increases symptom-free days and reduces total costs, the policy conclusion clearly favours early intervention. 相似文献
18.
19.
20.
Anal sphincter size measured by endosonography in healthy volunteers. Effect of age, sex, and parity. 总被引:8,自引:0,他引:8
M B Nielsen C Hauge O O Rasmussen M S?rensen J F Pedersen J Christiansen 《Acta radiologica (Stockholm, Sweden : 1987)》1992,33(5):453-456
The anal sphincter muscles consist of the circular internal and external sphincters together with the sling-shaped associated puborectalis muscle. Ten men, 10 women with no vaginal deliveries, and 10 women with one or more vaginal deliveries were studied with anal endosonography using a 7 MHz multiplanar endoprobe. The thickness of the internal sphincter and the thickness, length, and cross-sectional area of the external sphincter were measured and related to age, sex, and parity. Reproducibility was assessed by similar measurements on different days in 10 volunteers. Anal sphincter size was the same in men and women and was not affected by the number of child births. Internal sphincter muscle thickness increased with age. Anal manometry and electromyography with an anal sponge were performed in all volunteers but the results did not correlate to any of the anal sphincter dimensions. Our conclusion is that although there are some limitations, endosonography can be used to determine the size of the anal sphincter muscles. 相似文献