全文获取类型
收费全文 | 9879篇 |
免费 | 969篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 168篇 |
儿科学 | 392篇 |
妇产科学 | 205篇 |
基础医学 | 1302篇 |
口腔科学 | 128篇 |
临床医学 | 984篇 |
内科学 | 1713篇 |
皮肤病学 | 357篇 |
神经病学 | 1018篇 |
特种医学 | 470篇 |
外科学 | 1289篇 |
综合类 | 239篇 |
一般理论 | 5篇 |
预防医学 | 1243篇 |
眼科学 | 145篇 |
药学 | 688篇 |
中国医学 | 4篇 |
肿瘤学 | 516篇 |
出版年
2021年 | 103篇 |
2020年 | 71篇 |
2019年 | 112篇 |
2018年 | 137篇 |
2017年 | 131篇 |
2016年 | 100篇 |
2015年 | 122篇 |
2014年 | 202篇 |
2013年 | 301篇 |
2012年 | 339篇 |
2011年 | 370篇 |
2010年 | 235篇 |
2009年 | 221篇 |
2008年 | 399篇 |
2007年 | 493篇 |
2006年 | 417篇 |
2005年 | 375篇 |
2004年 | 375篇 |
2003年 | 359篇 |
2002年 | 354篇 |
2001年 | 340篇 |
2000年 | 405篇 |
1999年 | 320篇 |
1998年 | 192篇 |
1997年 | 146篇 |
1996年 | 153篇 |
1995年 | 149篇 |
1994年 | 141篇 |
1993年 | 121篇 |
1992年 | 281篇 |
1991年 | 227篇 |
1990年 | 264篇 |
1989年 | 224篇 |
1988年 | 236篇 |
1987年 | 202篇 |
1986年 | 203篇 |
1985年 | 227篇 |
1984年 | 140篇 |
1983年 | 107篇 |
1982年 | 116篇 |
1981年 | 79篇 |
1980年 | 80篇 |
1979年 | 117篇 |
1978年 | 106篇 |
1977年 | 87篇 |
1976年 | 104篇 |
1975年 | 83篇 |
1974年 | 93篇 |
1973年 | 93篇 |
1972年 | 74篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Oxygen-free radical production and reperfusion injury are complex mechanisms. New and improved methods for maximizing the benefits of reperfusion while minimizing reperfusion injury are on the horizon in the 1990s. Critical care nurses play a crucial role in the assessment, planning, and intervention of patients experiencing the deleterious effects of free radicals and reperfusion injury. Thus, a sound knowledge base in the pathophysiology of reperfusion injury, the detrimental effects of free radicals, and the potential benefits of free-radical scavengers is essential. 相似文献
82.
83.
84.
D. J. W. Hunter C. M. McKee N. A. Black C. F. B. Sanderson 《Quality of life research》1995,4(4):335-341
Our objective was to determine the extent to which lower urinary tract symptoms affect the general health status of men and contribute to the decision to undergo surgery. A cross-sectional population survey using postal questionnaires was conducted in the North West Thames health region, followed by a prospective cohort study of men undergoing prostatectomy (North West Thames and Oxford regions). The subjects in the first survey were 221 men aged 55 and over with previously reported mild, moderate or severe urinary symptoms; subjects in the second study were 388 men undergoing prostatectomy. Main outcome measures were selfreported symptom severity, bothersomeness and general health status (Nottingham Health Profilie, Part 1). The response rate among eligible responders in the population survey was 85.7%. Increasing symptom severity was associated with worsening NHP scores for energy, emotional reactions, sleep and physical mobility (p<0.01). Increasing bother-someness of symptoms was associated with emotional reactions, sleep and pain (p<0.05). Men undergoing surgery reported worse health status than men in the population with the same severity of symptoms as regards emotional reactions, energy and pain. For a given level of symptom severity, the impact of those symptoms on aspects of a man's general health status may be the determinant of seeking and undergoing surgery. Greater understanding of the factors that affect a man's response to his symptoms is needed in interpreting the decision to seek and accept treatment. 相似文献
85.
Assessment of self-poisoning patients by psychiatrists and junior medical staff. 总被引:1,自引:1,他引:0
下载免费PDF全文
![点击此处可从《Journal of the Royal Society of Medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Case notes of patients admitted to hospital or seen in the casualty department following an overdose were assessed in a standardized way. The medical records were deficient in several important areas, especially for those patients seen in casualty and not referred to a psychiatrist. If only selected patients were to be assessed by psychiatrists, closer monitoring of the psychiatric assessments and management initiated by junior medical staff would be required. Although the poor records may reflect lack of motivation as much as lack of education, there was no significant relationship between the doctors' attitudes towards self-poisoning patients in general and the standard of their assessments. 相似文献
86.
Sumeer Sathi Eugene Rossitch Jr. Matthew R. Moore Peter McL. Black 《Child's nervous system》1991,7(1):56-58
Harvey Cushing was a man of many talents. Not only was he a premier surgeon and scientist, but a prolific author and artist as well. In this paper, we present two postoperative sketches of pediatric brain tumors drawn by Dr. Cushing. These sketches are representative of drawings which accompany many of his operative notes at the Peter Bent Brigham Hospital. About 25% of Cushing's surgical sketches depict operations performed on children. The most commonly drawn childhood tumors were craniopharyngiomas and gliomas of the brain stem and cerebellum. These drawings reveal how Cushing maintained detailed records of his surgical experience. It is clearly evident from these records that Dr. Cushing gained substantial experience in the treatment of pediatric brain tumors. 相似文献
87.
Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model. 相似文献
88.
D M Stout L A Black C Barcelon-Yang W L Matier B S Brown C Y Quon H F Stampfli 《Journal of medicinal chemistry》1989,32(8):1910-1913
In an effort to find a replacement for the iv antiarrhythmic drug lidocaine having reduced systemic and central nervous system effects, activity against supraventricular as well as ventricular arrhythmias, and a biological half-life of less than 15 min, derivatives of the orally active class Ic clinical agent 2,6-bis(1-pyrrolidinylmethyl)-4-benzamidophenol, 1 (ACC-9358), were synthesized and tested. Compounds with ester groups attached to the phenyl ring were either weakly active or toxic. Replacement of the formanilide function with alkyl esters afforded compounds with antiarrhythmic activity in the range of 1. When the ester carboxyl was separated from the bis(aminomethyl)phenol by methylene units, very short half-lives were observed in human blood. In general, these compounds also had low lipophilic character. 相似文献
89.
90.
Composite tissue (limb) allografts in rats. III. Development of donor-host lymphoid chimeras in long-term survivors 总被引:2,自引:0,他引:2
C W Hewitt K S Black S F Dowdy G A Gonzalez B M Achauer D C Martin D W Furnas E B Howard 《Transplantation》1986,41(1):39-43
Eight LEW rat recipients possessing long-term-surviving (206-701 days) LBN vascularized hind limb allografts (CTAs) were tested for donor-host lymphoid chimerism. The recipients received various cyclosporine (CsA) treatment protocols in order to induce indefinite CTA acceptance. Histological examination of long-term-surviving CTAs demonstrated normal-appearing bone marrow in the donor limb. Lymphocytes isolated from host hemopoietic tissues (peripheral blood and/or spleen) by ficoll-hypaque density gradient centrifugation were tested against LEW-anti-BN antisera. Comparisons were made to standard curves employing various known concentrations of LBN and LEW cell combinations. The level of lymphocyte agglutination (dependent variable) showed a significant (P less than 0.025-0.005) linear relationship to the concentration of LBN donor cells (independent variable) present. Lymphocyte suspensions isolated from long-term CTA host peripheral blood and/or spleen showed a mean of 19.7% (+/- 9.7-95% confidence interval) donor LBN mononuclear cells present. Thus, it appeared that lymphoid cells originated from, and/or were released from LBN donor bone marrow into the circulation, resulting in chimeric repopulation of hemopoietic tissues. The presence of donor immunocytes in these limb allograft recipients may have been beneficial, and thus could have helped contribute to the long-term CTA survival observed. 相似文献