全文获取类型
收费全文 | 1953篇 |
免费 | 138篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 97篇 |
妇产科学 | 67篇 |
基础医学 | 181篇 |
口腔科学 | 70篇 |
临床医学 | 150篇 |
内科学 | 447篇 |
皮肤病学 | 43篇 |
神经病学 | 103篇 |
特种医学 | 91篇 |
外科学 | 239篇 |
综合类 | 311篇 |
预防医学 | 116篇 |
眼科学 | 26篇 |
药学 | 65篇 |
1篇 | |
中国医学 | 1篇 |
肿瘤学 | 81篇 |
出版年
2023年 | 10篇 |
2022年 | 13篇 |
2021年 | 28篇 |
2020年 | 27篇 |
2019年 | 32篇 |
2018年 | 29篇 |
2017年 | 17篇 |
2016年 | 21篇 |
2015年 | 62篇 |
2014年 | 64篇 |
2013年 | 62篇 |
2012年 | 78篇 |
2011年 | 119篇 |
2010年 | 109篇 |
2009年 | 86篇 |
2008年 | 97篇 |
2007年 | 85篇 |
2006年 | 100篇 |
2005年 | 78篇 |
2004年 | 110篇 |
2003年 | 63篇 |
2002年 | 60篇 |
2001年 | 54篇 |
2000年 | 50篇 |
1999年 | 56篇 |
1998年 | 41篇 |
1997年 | 40篇 |
1996年 | 34篇 |
1995年 | 22篇 |
1994年 | 33篇 |
1993年 | 18篇 |
1992年 | 34篇 |
1991年 | 28篇 |
1990年 | 24篇 |
1989年 | 24篇 |
1988年 | 25篇 |
1987年 | 29篇 |
1986年 | 27篇 |
1985年 | 23篇 |
1984年 | 17篇 |
1983年 | 12篇 |
1982年 | 17篇 |
1979年 | 20篇 |
1978年 | 10篇 |
1976年 | 8篇 |
1975年 | 8篇 |
1974年 | 8篇 |
1973年 | 11篇 |
1970年 | 8篇 |
1966年 | 10篇 |
排序方式: 共有2093条查询结果,搜索用时 31 毫秒
51.
Acquired granular pool defect in stored platelets 总被引:1,自引:0,他引:1
Platelets stored as concentrates (PC) for 72 h at 22 degrees C develop a functional defect. Alterations in adenine nucleotides of platelets have been shown to affect platelet function. Adenine nucleotide content of platelets was measured before and after storage and a decrease of 27.1 /+- 1.7% (mean /+- SE) in ATP and 39.1 /+- 2.6% in ADP were found in 34 PC stored with final volume of 50 ml. In 11 PC with 30 ml volume. ATP and ADP decreased by 39.4 /+- 3.2% and 49.4 /+- 2.1%, respectively. The mean ATP to ADP ratio of stored platelets was significantly higher than of fresh platelets in both groups, suggesting a relatively greater decrease in granular than metabolic pool nucleotides. Levels of low affinity platelet factor 4 measured by radioimmunoassay in plasma from 0.86 /+- 0.08 microgram/ml in the fresh PC to 8.59 /+- 0.39 microgram/ml in stored PC, indicating a concomitant alpha-granular secretion. Labeling of metabolic pool with 14C-adenine revealed a mean decrease in the adenylate energy charge of 2.0 /+- 0.4% in 12 of 16 stored PC, with a lower ATP and higher hypoxanthine labeling in stored as compared to fresh platelets. These observations suggest that stored platelets develop an acquired defect in both dense and alpha granules and in their ability to maintain ATP homeostasis. 相似文献
52.
OBJECTIVE: Oral but not transdermal oestrogen administration reduces IGF-I, and increases GH binding protein (GHBP) reflecting effects on hepatic endocrine function in postmenopausal women. As progestogens attenuate the effects of oestrogen on circulating lipid levels according to their androgenic properties, we have investigated the impact of progestogen types on the hepatic endocrine effects of oestrogen. DESIGN: Four progestogens differing in androgenicity were co-administered in a monthly cyclical regimen in random order to postmenopausal women receiving either oral (n = 9, premarin 1.25 mg) or transdermal (n = 10, Estraderm 100 microg patches twice weekly). The four progestogens were cyproterone acetate (CA 5 mg, antiandrogenic), dydrogesterone (20 mg, neutral), medroxyprogesterone acetate (MPA 10 mg, mildly androgenic), norethisterone (2.5 mg, androgenic). PATIENTS: Nineteen postmenopausal women (age 57 +/- 3 years, mean +/- SE) were studied. MEASUREMENTS: The effects of oestrogen alone and the combined effects with each progestogen type on IGF-I, GHBP, SHBG, cholesterol, triglycerides and lipoprotein(a) were investigated. RESULTS: Mean IGF-I fell while GHBP and SHBG levels increased with oral (P < 0.01) but not transdermal oestrogen administration. When the combined effects were examined, progestogens did not affect IGF-I, GHBP and SHBG during oral oestrogen treatment, while they significantly increased (P < 0.01) mean IGF-I levels during transdermal therapy. Among the progestogen types, only norethisterone prevented the fall in IGF-I induced by oral oestrogen. During transdermal therapy, MPA and norethisterone but not CA or dydrogesterone significantly increased (P < 0.005) IGF-I. The rise in GHBP induced by oral oestrogens tended to be lower during co-administration of MPA and norethisterone. The increase in SHBG induced by oral oestrogen was attenuated (P < 0.05) by norethisterone which was the only progestogen that lowered SHBG (P < 0.05) during transdermal oestrogen treatment. Mean IGF-I was higher (P < 0.001), GHBP and SHBG lower during co-administration of androgenic progestogens (MPA and norethisterone). CONCLUSIONS: Oestrogen effects on IGF-I, GHBP and SHBG are dependent on the route of administration with progestogens having variable effects. Among the progestogen types, norethisterone, the most androgenic, had the greatest effect, particularly on IGF-I. Progestogens modulate the effects of oestrogen on hepatic endocrine function in relation to their intrinsic androgenic properties. The modulatory effects of progestogens on IGF-I during oestrogen therapy may have long-term implications for lean body mass. 相似文献
53.
A human monoclonal autoantibody recognizes a neoantigen on glycoprotein IIIa expressed on stored and activated platelets 总被引:2,自引:1,他引:2
We prepared a heterohybrid cell line that secretes a human IgM monoclonal autoantibody that recognizes an antigen found on thrombin-activated or stored platelets. The surface expression of the epitope recognized by this autoantibody, 5E5, increases with time as platelets age in vitro, suggesting that it may represent a senescence or activation-specific antigen. 5E5 binds to the purified platelet membrane glycoprotein (GP) IIb-IIIa complex in an enzyme-linked immunosorbent assay (ELISA). In an immunoblot technique, 5E5 binds to a protein with an apparent mol wt of 95,000, which is identical to that of GPIIIa under nonreduced conditions. In crossed immunoelectrophoresis (CIE), the predominant antigen recognized by 5E5 is contained in the GPIIb-IIIa precipitin arc. An additional precipitin arc recognized by 5E5 is often observed only on gels derived from lysates of platelets stored under blood bank conditions for greater than 3 days. These findings illustrate the usefulness of human monoclonal antibodies for the identification of membrane neoantigens expressed as a result of platelet activation or revealed as platelets age in vitro. 相似文献
54.
S. A. Pilkington R. Bhome R. E. Welch F. Ku C. Warden S. Harris J. Hicks C. Richardson T. C. Dudding J. S. Knight A. T. King A. H. Mirnezami N. E. Beck P. H. Nichols K. P. Nugent 《Techniques in coloproctology》2018,22(7):545-551
Background
Botulinum toxin injected into the internal anal sphincter is used in the treatment of chronic anal fissure but there is no standardised technique for its administration. This randomised single centre trial compares bilateral (either side of fissure) to unilateral injection.Methods
Participants were randomised to receive bilateral (50?+?50 units) or unilateral (100 units) Dysport® injections into the internal anal sphincter in an outpatient setting. Injection-related pain assessed by visual analogue scale was the primary outcome measure. Secondary outcomes were healing rate, fissure pain, incontinence, and global health scores.Results
Between October 2008 and April 2012, 100 patients with chronic anal fissure were randomised to receive bilateral or unilateral injections. Injection-related pain was comparable in both groups. There was no difference in healing rate. Initially, there was greater improvement in fissure pain in the bilateral group but at 1 year the unilateral group showed greater improvement. Cleveland Clinic Incontinence score was lower in the unilateral group in the early post-treatment period and global health assessment (EuroQol EQ-VAS) was higher in the unilateral group at 1 year.Conclusions
Injection-related pain was similar in bilateral and unilateral injection groups. Unilateral injection was as effective as bilateral injections in healing and improving fissure pain without any deterioration in continence.55.
Lauren Desrosiers Sarah Scollon Rebecca Littlejohn Kimberly Nugent Rebecca Althaus Jessica Corredor Emily Berenson Rachel Wyatt Timothy Griffin Kelly Vallance Jonathan Gill Gail Tomlinson Juan Carlos Bernini Angshumoy Roy George Miles Jacquelyn Reuther Shashikant Kulkarni Christine Eng Sharon Plon 《Molecular genetics and metabolism》2021
56.
Colette Cunningham Zena Moore Tom O. Connor Declan Patton Dr Dhani Bux Dr Linda Nugent 《Journal of neonatal nursing : JNN》2021,27(3):188-190
AimThe aim of this contemporary issue paper is to challenge the premise that the term “eHealth” is relatable to patient or service users only. It will be critically explored if the term can be broadened to include neonatal nurse education interventions.DesignA review of current literature will form the basis for the critical discussion of the term eHealth, and why it can be associated with neonatal nurse education.MethodsThe critical discussion will identify and review past and current literature relating to eHealth and its origins. It will portray the viability of the term eHealth as more than just a patient associated intervention, and why it should also be encompassed as a neonatal nurse education option.ConclusioneHealth is traditionally identifiable as a service user intervention or source of information. The term should be broadened to encompass neonatal nurse education and used as a resource that is easily accessible and user friendly. This will in turn encourage the personal and professional development of neonatal nurses and should ultimately contribute to evidence based best practices in the clinical environment, despite the current global pandemic. 相似文献
57.
Anterior cruciate ligament injury about 20 years post‐treatment: A kinematic analysis of one‐leg hop
下载免费PDF全文
![点击此处可从《Scandinavian journal of medicine & science in sports》网站下载免费的PDF全文](/ch/ext_images/free.gif)
E. Tengman H. Grip AK. Stensdotter C. K. Häger 《Scandinavian journal of medicine & science in sports》2015,25(6):818-827
Reduced dynamic knee stability, often evaluated with one‐leg hops (OLHs), is reported after anterior cruciate ligament (ACL) injury. This may lead to long‐standing altered movement patterns, which are less investigated. 3D kinematics during OLH were explored in 70 persons 23 ± 2 years after ACL injury; 33 were treated with physiotherapy in combination with ACL reconstruction (ACLR) and 37 with physiotherapy alone (ACLPT). Comparisons were made to 33 matched controls. We analyzed (a) maximal knee joint angles and range of motion (flexion, abduction, rotation); (b) medio‐lateral position of the center of mass (COM) in relation to knee and ankle joint centers, during take‐off and landing phases. Unlike controls, ACL‐injured displayed leg asymmetries: less knee flexion and less internal rotation at take‐off and landing and more lateral COM related to knee and ankle joint of the injured leg at landing. Compared to controls, ACLR had larger external rotation of the injured leg at landing. ACLPT showed less knee flexion and larger external rotation at take‐off and landing, and larger knee abduction at Landing. COM was more medial in relation to the knee at take‐off and less laterally placed relative to the ankle at landing. ACL injury results in long‐term kinematic alterations during OLH, which are less evident for ACLR. 相似文献
58.
A Chaudhry S Hallam A Chambers AK Sahu S Govindarajulu S Cawthorn 《Annals of the Royal College of Surgeons of England》2015,97(5):364-368
IntroductionPostoperative pain after breast surgery is one of the major factors contributing to delay in mobilisation and prolonged hospital stay. A retrospective analysis was performed of patients undergoing skin sparing mastectomy and insertion of a subpectoral implant. The aim was to determine whether the use of an elastomeric local anaesthetic pump improved pain control and length of stay.MethodsTwenty-five consecutive patients undergoing the above procedure were sited with an elastomeric local anaesthetic infusion pump intraoperatively, in addition to standard regular and pro re nata analgesia. The control group comprised 25 patients undergoing the same procedure in the same year who received standard analgesia alone. Visual analogue scale scores were recorded for the duration of inpatient stay, as was any further analgesic requirement.ResultsThe median age was 51 years (range: 26–75 years) in the intervention group and 50 years (range: 28–70 years) in the control group. The mean visual analogue scale score was 0.28 (standard deviation [SD]: 0.61) at 24 hours for the intervention group and 1.84 (SD: 0.37) for the control group (p<0.0001). The mean length of stay was 1.8 days (SD: 0.71 days) for the intervention group and 2.28 days (SD: 0.94 days) for the control group (p=0.15). There were no complications involving catheter placement, leakage or toxicity relating to use of the local anaesthetic.ConclusionsThere was significantly reduced pain with the use of the local anaesthetic infusion pump. The elastomeric pump is a step towards enhanced patient recovery after breast surgery in the case of skin sparing mastectomy and subpectoral tissue expander reconstruction. 相似文献
59.
60.
Abstract. A case of warm antibody auto-immune hemolytic anemia is described in which the serum antibody, and an eluate from the patient's red cells, both had anti-U specificity. The antibody did not react with Rhnull red cells, and gave weaker reactions with -D- red cells than with other U-positive red cells. Five other anti-U sera were tested in comparative titrations and some of these also reacted more weakly against -D- red cells than against red cells having common Rh phenotypes. 相似文献