全文获取类型
收费全文 | 3090篇 |
免费 | 202篇 |
国内免费 | 80篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 92篇 |
妇产科学 | 84篇 |
基础医学 | 408篇 |
口腔科学 | 40篇 |
临床医学 | 364篇 |
内科学 | 561篇 |
皮肤病学 | 47篇 |
神经病学 | 262篇 |
特种医学 | 321篇 |
外科学 | 382篇 |
综合类 | 119篇 |
一般理论 | 4篇 |
预防医学 | 334篇 |
眼科学 | 50篇 |
药学 | 178篇 |
中国医学 | 8篇 |
肿瘤学 | 112篇 |
出版年
2023年 | 13篇 |
2022年 | 22篇 |
2021年 | 53篇 |
2020年 | 33篇 |
2019年 | 45篇 |
2018年 | 46篇 |
2017年 | 42篇 |
2016年 | 40篇 |
2015年 | 56篇 |
2014年 | 77篇 |
2013年 | 97篇 |
2012年 | 113篇 |
2011年 | 121篇 |
2010年 | 97篇 |
2009年 | 125篇 |
2008年 | 127篇 |
2007年 | 162篇 |
2006年 | 132篇 |
2005年 | 124篇 |
2004年 | 121篇 |
2003年 | 108篇 |
2002年 | 111篇 |
2001年 | 109篇 |
2000年 | 113篇 |
1999年 | 90篇 |
1998年 | 111篇 |
1997年 | 99篇 |
1996年 | 86篇 |
1995年 | 68篇 |
1994年 | 57篇 |
1993年 | 65篇 |
1992年 | 71篇 |
1991年 | 60篇 |
1990年 | 57篇 |
1989年 | 64篇 |
1988年 | 68篇 |
1987年 | 49篇 |
1986年 | 45篇 |
1985年 | 44篇 |
1984年 | 29篇 |
1983年 | 24篇 |
1982年 | 22篇 |
1981年 | 11篇 |
1980年 | 15篇 |
1979年 | 11篇 |
1978年 | 12篇 |
1977年 | 19篇 |
1976年 | 17篇 |
1975年 | 17篇 |
1973年 | 7篇 |
排序方式: 共有3372条查询结果,搜索用时 265 毫秒
991.
Rosalind Woodcock Ray. Power Max. Kamien Charles Waddell 《The Australian journal of rural health》1996,4(2):96-103
ABSTRACT: This study was designed to develop a quick methodology to assess the healthcare needs of a rural community and to determine what factors make these communities 'happy' or 'unhappy' with respect to medical service provision. Two rural shires of approximately 4000 people each were chosen from different health regions of Western Australia. The methodology consisted of interviews with healthcare providers and key community informants as well as a community questionnaire. The interviewing process showed that key community informants offered no new information in addition to that already provided by the healthcare providers. Furthermore, all key points would have been covered by interviewing approximately 60% of all healthcare providers in each community. Hand delivery of the community questionnaire yielded the highest response rate. The level of community satisfaction with general practitioner (GP) and hospital services determines whether a community is medically 'happy' or 'unhappy'. 相似文献
992.
993.
目的探讨128层螺旋CT冠状动脉造影的临床应用价值。方法对121例患者行128层螺旋CT冠状动脉造影检查,利用其先进的后处理功能对冠状动脉进行重组,以显示冠状动脉各主支及分支,并对冠状动脉病变进行诊断。对其中两例诊断冠状动脉狭窄病例行选择性血管造影检查。结果121例行128层螺旋CT冠状动脉造影均成功显示冠状动脉各主支及分支,发现冠状动脉管壁钙化59例,软斑块形成27例,其中64例冠状动脉伴有不同程度的狭窄。结论128层螺旋CT冠状动脉造影对于冠心病的诊断是一种安全可靠的检查方法。 相似文献
994.
Abstract
Aims/hypothesis. Testicular Sertoli cells protect allogeneic islet grafts from rejection after transplantation into animals with chemically
induced diabetes. The aims of this study were to determine whether Sertoli cells can protect syngeneic islets from autoimmune
destruction after transplantation into non-obese diabetic (NOD) mice and, if so, whether protection is due to Sertoli cell
expression of Fas ligand (FasL), believed to be the mechanism that protects against allograft rejection.?Methods. We compared the survival of syngeneic islets transplanted under the renal capsule of non-obese diabetic mice, alone and
together with purified Sertoli cells prepared from testes of newborn non-obese diabetic mice. Additionally, we examined the
composition of the islet and Sertoli cell co-transplants by immunohistochemistry to determine whether islet graft survival
correlated with Sertoli cell expression of Fas ligand.?Results. Sertoli cell doses of 1, 2 and 4 × 106 cells produced a dose-dependent prolongation of median islet graft survival from 11 days (islets alone) to 32 days (islets
+ 4 × 106 Sertoli cells); addition of 8 × 106 Sertoli cells to the islet grafts decreased, however, median survival to 8 days. Immunohistochemical analysis of the islet
and Sertoli cell co-transplants showed a correlation between Fas ligand expression by Sertoli cells and graft infiltration
by neutrophilic leucocytes, leading to islet beta-cell destruction and diabetes recurrence.?Conclusion/interpretation. Sertoli cells exert opposing effects on survival of syngeneic islet grafts in non-obese diabetic mice: Fas ligand-dependent
neutrophil infiltration and graft destruction, and Fas ligand-independent protection of the graft from autoimmune destruction.
[Diabetologia (2000) 43: 474–480]
Received: 13 December 1999 and in revised form: 20 January 2000 相似文献
995.
Neuroepithelial bodies of pulmonary airways serve as a reservoir of progenitor cells capable of epithelial regeneration 总被引:16,自引:0,他引:16 下载免费PDF全文
Remodeling of the conducting airway epithelium is a common finding in the chronically injured lung and has been associated with increased risk for developing lung cancer. Pulmonary neuroendocrine cells and clusters of these cells termed neuroepithelial bodies (NEBs) play a central role in each of these processes. We previously developed an adult mouse model of airway injury and repair in which epithelial regeneration after naphthalene-induced Clara cell ablation occurred preferentially at airway branch points and gave rise to nascent Clara cells. Continued repair was accompanied by NEB hyperplasia. We now provide the following evidence that the NEB microenvironment serves as a source of airway progenitor cells that contribute to focal regeneration of the airway epithelium: 1) nascent Clara cells and NEBs localize to the same spatial domain; 2) within NEB, both Clara cell secretory protein- and calcitonin gene-related peptide-immunopositive cells are proliferative; 3) the NEB microenvironment of both the steady-state and repairing lung includes cells that are dually immunopositive for Clara cell secretory protein and calcitonin gene-related peptide, which were previously identified only within the embryonic lung; and 4) NEBs harbor variant Clara cells deficient in cytochrome P450 2F2-immunoreactive protein. These data suggest that the NEB microenvironment is a reservoir of pollutant-resistant progenitor cells responsive to depletion of an abundant airway progenitor such as the Clara cell. 相似文献
996.
OBJECTIVE: To explore gynecologists' knowledge, training, and practice experience with genetic screening and DNA-based testing. METHODS: A questionnaire survey was sent to 1,248 ACOG Fellows, of whom 564 (45%) responded. One hundred thirty-four respondents (24%) reported that they do not order DNA-based tests or take family histories to screen for heritable diseases or disorders. Results from the 428 respondents who provide genetic screening services are reported. RESULTS: Most physicians (90%) knew that genetic tests are most informative when used in conjunction with family histories. Gynecologists gave more correct responses regarding genetic testing for breast and ovarian cancers than for colon cancer and other adult-onset diseases. Sixty-five percent of the respondents had not received formal training in DNA-based testing in gynecologic practice. Older physicians were less likely to have had training. Younger physicians generally gave more correct responses on the knowledge portion of the survey (r = -.165, P < .01). Physicians who had formal training in genetics gave more correct answers. Physicians who order DNA-based tests scored higher than those who do not and had no formal training, but not higher than those who had formal training and do not order DNA-based tests. CONCLUSION: Gynecologists were more knowledgeable about genetic issues pertaining to breast and ovarian cancer than to other cancers or certain adult-onset disorders. Training appeared to increase knowledge. Increased training and affiliation with genetic specialists and others could improve gynecologists' ability to use genetic screening in clinical practice. 相似文献
997.
JI Tang TP Shakespeare JJ Lu YH Chan KM Lee LC Wong RK Mukherjee MF Back 《Journal of Medical Imaging and Radiation Oncology》2008,52(5):497-502
The palliative radiotherapeutic management of unresectable non‐small‐cell lung cancer is controversial, with various fractionation (Fx) schedules available. We aimed to determine patient’s choice of Fx schedule after involvement in a decision‐making process using a decision board. A decision board outlining the various advantages and disadvantages apparent in the Medical Research Council study of Fx schedules (17 Gy in two fractions vs 39 Gy in 13 fractions) was discussed with patients who met Medical Research Council eligibility criteria. Patients were then asked to indicate their preferred Fx schedules, reasons and their level of satisfaction with being involved in the decision‐making process. Radiation oncologists (RO) could prescribe radiotherapy schedules irrespective of patients’ preferences. Of 92 patients enrolled, 55% chose the longer schedule. English‐speaking patients were significantly more likely to choose the longer schedule (P = 0.02, 95% confidence interval: 1.2–7.6). Longer Fx was chosen because of longer survival (90%) and better local control (12%). Shorter Fx was chosen for shorter overall treatment duration (80%), cost (61%) and better symptom control (20%). In all, 56% of patients choosing the shorter schedule had their treatment altered by the treating RO, whereas only 4% of patients choosing longer Fx had their treatment altered (P < 0.001). Despite this, all (100%) patients were satisfied with being involved in the decision‐making process. The decision board was useful in aiding decision‐making, with both Fx schedules being acceptable to patients. Interestingly, despite the longer average survival associated with longer Fx, nearly half of the patients believed that this was not as important as a shorter duration of treatment and lower cost. Despite patients’ preferences, there were significant alterations of preferred schedules because of RO’s own biases. 相似文献
998.
Tardif SD Ziegler TE Power M Layne DG 《The Journal of clinical endocrinology and metabolism》2005,90(1):335-339
Common marmosets, a New World primate, respond to a modest energy restriction with early termination of the pregnancy. Within female marmosets, comparisons (n = 6) between a normal, term pregnancy and a restriction-induced aborted pregnancy were used to establish cortisol, free estradiol, and chorionic gonadotropin (CG) as urinary markers of placental and fetal function under these two conditions. Abortions occurred 11-47 d after a 25% energy reduction during midpregnancy for all females. Cortisol concentrations were significantly lower in the last 2 wk for the restricted pregnancy than for matched samples in the normal term pregnancy. Both estradiol and estrone were examined in free and conjugated forms. Only free estradiol showed a significant reduction in mean concentrations during midpregnancy for the restricted females compared with their normal, term pregnancies. Mean CG levels from each female served as an independent marker of placental differentiation and function. CG levels were significantly lower during the 2 wk before abortion compared with matched days from a normal, term pregnancy. These data provide evidence that estradiol and cortisol are useful markers of placental and fetal viability in the common marmoset, and their reduced concentration following energy restriction suggests that restriction is not acting as a classical stressor by increasing cortisol and, subsequently, estradiol concentration. 相似文献
999.
1000.
Jackson H McGorry P Edwards J Hulbert C Henry L Harrigan S Dudgeon P Francey S Maude D Cocks J Killackey E Power P 《Psychological medicine》2005,35(9):1295-1306
OBJECTIVES: Cognitively oriented psychotherapy for early psychosis (COPE) is aimed at facilitating the adjustment of the person, and preventing or alleviating secondary morbidity in the wake of the first psychotic episode. The present study reports on the outcomes of a controlled trial comparing two conditions: COPE versus No-COPE. METHOD: Ninety-one people participated in the trial which was analysed by intention-to-treat, including 12 people who were assigned to COPE but refused to participate. Assessments were conducted at pre-treatment, mid-treatment and post-treatment. Hospital readmission data were obtained through a Psychiatric Case Register. The study was conducted in a front-line public mental health service, the Early Psychosis Prevention and Intervention Centre (EPPIC). Clients in both COPE and No-COPE were provided with full access to the complete range of EPPIC services. RESULTS: There were no significant differences between the two conditions on the nine primary outcome variables. Hospital readmissions were assessed for each client at yearly intervals up to 4 years following the completion of treatment and again there were no significant between-group differences. CONCLUSIONS: The study indicated that there was no significant advantage to COPE over and above routine care at EPPIC. 相似文献