全文获取类型
收费全文 | 50021篇 |
免费 | 3622篇 |
国内免费 | 104篇 |
专业分类
耳鼻咽喉 | 386篇 |
儿科学 | 1888篇 |
妇产科学 | 1777篇 |
基础医学 | 6013篇 |
口腔科学 | 596篇 |
临床医学 | 8793篇 |
内科学 | 9121篇 |
皮肤病学 | 751篇 |
神经病学 | 4530篇 |
特种医学 | 880篇 |
外国民族医学 | 33篇 |
外科学 | 4376篇 |
综合类 | 622篇 |
一般理论 | 79篇 |
预防医学 | 7036篇 |
眼科学 | 536篇 |
药学 | 2808篇 |
1篇 | |
中国医学 | 89篇 |
肿瘤学 | 3432篇 |
出版年
2023年 | 280篇 |
2022年 | 368篇 |
2021年 | 980篇 |
2020年 | 658篇 |
2019年 | 1070篇 |
2018年 | 1220篇 |
2017年 | 839篇 |
2016年 | 961篇 |
2015年 | 1038篇 |
2014年 | 1428篇 |
2013年 | 2398篇 |
2012年 | 3420篇 |
2011年 | 3660篇 |
2010年 | 1951篇 |
2009年 | 1829篇 |
2008年 | 3232篇 |
2007年 | 3685篇 |
2006年 | 3543篇 |
2005年 | 3445篇 |
2004年 | 3327篇 |
2003年 | 3167篇 |
2002年 | 2986篇 |
2001年 | 386篇 |
2000年 | 273篇 |
1999年 | 397篇 |
1998年 | 648篇 |
1997年 | 514篇 |
1996年 | 446篇 |
1995年 | 364篇 |
1994年 | 369篇 |
1993年 | 363篇 |
1992年 | 269篇 |
1991年 | 232篇 |
1990年 | 229篇 |
1989年 | 188篇 |
1988年 | 187篇 |
1987年 | 200篇 |
1986年 | 170篇 |
1985年 | 194篇 |
1984年 | 211篇 |
1983年 | 215篇 |
1982年 | 267篇 |
1981年 | 246篇 |
1980年 | 193篇 |
1979年 | 143篇 |
1978年 | 115篇 |
1977年 | 139篇 |
1976年 | 115篇 |
1975年 | 96篇 |
1973年 | 89篇 |
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
91.
Sharon Gohari BS Charles Gambla MD Mary Healey RN Gail Spaulding RN Kenneth B. Gordon MD James Swan MD Brian Cook MD Dennis P. West PhD Jean-Christophe Lapiere MD 《Dermatologic surgery》2002,28(12):1107-1114
BACKGROUND: Human Skin Substitute (Apligraf, Organogenesis, Inc., Canton, MA) is a bi-layered tissue-engineered living biological dressing developed from neonatal foreskin. It consists of a bovine collagen matrix containing human fibroblasts with an overlying sheet of stratified human epithelium containing living human keratinocytes. Human Skin Substitute (HSS) appears to be immunologically inert, and has shown usefulness in the treatment of chronic and acute wounds. OBJECTIVE: Primary objectives were to evaluate the safety and efficacy of HSS in the treatment of full-thickness wounds in a prospective case series. Secondary objectives were to determine the rate of complete wound reepithelialization, incidence of complete wound healing, pain at wound site, overall cosmetic outcome, and patient satisfaction. METHODS: Fourteen patients were enrolled in the study, of which 12 were evaluable. HSS was applied in a blinded fashion to 6 of the patients immediately following Mohs or excisional surgery for skin cancer. The remaining 6 patients were allowed to heal by secondary intention. Both groups were evaluated at weekly appointments until complete reepithelialization occurred. During each evaluation, wound quality was assessed through the Vancouver Burn Scar Assessment Scale by the investigator and an independent blinded dermatologist. The investigator, blinded observer, and patient further evaluated the cosmetic outcome of the wound through the use of a Visual Analog Scale over a 6-month period. RESULTS: HSS patients and secondary intention patients were equivalent in comorbid factors such as pain, erythema, edema, exudate, infection, or hematoma between the groups. The incidence of complete wound healing at 6 months was 100% for both groups. Both groups also appeared to heal at similar rates, as defined by the complete reepithelialization of the wound. HSS patients ultimately resulted in more pliable and less vascular wounds as defined by the Vancouver Burn Scar Assessment Scale. Patient satisfaction with cosmetic outcome in both groups was positive at 6 months. CONCLUSIONS: HSS appears to be a safe, well-tolerated biological dressing with equivalent comorbid factors to secondary intention healing. HSS, however, seems to produce a more pliable and less vascular scar than those developed through healing by secondary intention. HSS also appears to produce more satisfactory cosmetic results when compared to secondary intention healing. 相似文献
92.
Body pain and treatment response in late-life depression. 总被引:2,自引:0,他引:2
Jordan F Karp Debra Weiner Karen Seligman Meryl Butters Mark Miller Ellen Frank Jacqueline Stack Benoit H Mulsant Bruce Pollock Mary Amanda Dew David J Kupfer Charles F Reynolds 《The American journal of geriatric psychiatry》2005,13(3):188-194
OBJECTIVE: The authors investigated the influence of body pain on 1) time to treatment response and 2) suicidal ideation, in late-life depression. They hypothesized that higher levels of body pain would predict a longer time to and lower likelihood of response, and increased levels of suicidal ideation. METHODS: Subjects (N=187) were older adult outpatients (age > or =69 years), with current episodes of major depression, who were openly treated with paroxetine up to 40 mg daily and weekly interpersonal psychotherapy. Response was defined as 3 consecutive weeks of Hamilton Rating Scale for Depression at < or =10. Body pain was measured with the Bodily Pain Index of the SF-36 quality-of-life assessment. Authors used survival-analysis models on the responder sample to test the effect of body pain on response, after controlling for severity of depression. RESULTS: Overall response rate was 75.4%. Nonresponders reported more severe pain at baseline. After covarying for severity of baseline depression, no effect was found for physical pain on time-to-response or degree of suicidality. Bodily pain remained stable during acute treatment for responders, independent of depression response to combination psychotherapy and antidepressant treatment. CONCLUSIONS: Older adult patients with higher levels of physical pain can still respond to antidepressant treatment; however, reported bodily pain may be associated with a more difficult-to-treat depression. 相似文献
93.
Biodistribution and pharmacokinetics of the alphavbeta3-selective tracer 18F-galacto-RGD in cancer patients. 总被引:5,自引:0,他引:5
Ambros J Beer Roland Haubner Michael Goebel Stephan Luderschmidt Mary E Spilker Hans-Jürgen Wester Wolfgang A Weber Markus Schwaiger 《Journal of nuclear medicine》2005,46(8):1333-1341
(18)F-Galacto-RGD has been developed for PET of alpha(v)beta(3) integrin expression, a receptor involved in, for example, angiogenesis and metastasis. Our aim was to study the kinetics and biodistribution of (18)F-Galacto-RGD in cancer patients. METHODS: Nineteen patients with metastases of malignant melanoma (n = 7), sarcomas (n = 10), or osseous metastases (n = 2) were examined. After injection of 133-200 MBq (18)F-Galacto-RGD, 3 consecutive emission scans from the pelvis to the thorax or dynamic emission scans of the tumor over 60 min, followed by 1 static emission scan of the body, were acquired. Time-activity curves and standardized uptake values (SUVs) were derived by image region-of-interest analysis with image-based arterial input functions. Compartmental modeling was used to derive the distribution volume for muscle tissue and tumors. RESULTS: (18)F-Galacto-RGD showed rapid blood clearance and primarily renal excretion. SUVs in tumors ranged from 1.2 to 9.0. Tumor-to-blood and tumor-to-muscle ratios increased over time, with peak ratios of 3.1 +/- 2.0 and 7.7 +/- 4.3, respectively, at 72 min. The tumor kinetics were consistent with a 2-tissue compartment model with reversible specific binding. Distribution volume values were, on average, 4 times higher for tumor tissue (1.5 +/- 0.8) than those for muscle tissue (0.4 +/- 0.1). The data suggest that there was only minimal free and bound (specific or nonspecific) tracer in muscle tissue. CONCLUSION: (18)F-Galacto-RGD demonstrates a highly favorable biodistribution in humans with specific receptor binding. Most important, this study shows that (18)F-Galacto-RGD allows visualization of alpha(v)beta(3) expression in tumors with high contrast. Consequently, this tracer offers a new strategy for noninvasive monitoring of molecular processes and may supply helpful information for planning and controlling of therapeutic approaches targeting the alpha(v)beta(3) integrin. 相似文献
94.
Andrea DiMartini Lubna Javed Sarah Russell Mary Amanda Dew Mary Grace Fitzgerald Ashok Jain John Fung 《Liver transplantation》2005,11(6):679-683
Alcohol and tobacco use commonly co-occur, with at least 90% of those with an alcohol problem also using tobacco. Thus, 3 years ago when we discovered higher rate of late deaths due to lung and oropharyngeal cancer in patients who had received a transplant for alcoholic liver disease (ALD), we hypothesized that these patients were continuing to expose themselves to tobacco after liver transplantation (post-LTX) and that this behavior was increasing their risk for cancer. We subsequently began a prospective investigation of post-LTX tobacco use in patients having undergone LTX for ALD (n = 172). For 33 recipients we had data starting from our first assessment at 3 months post-LTX and for this subgroup we report on the details of the timing of tobacco use resumption and the redevelopment of nicotine addiction. We found that on average more than 40% are smoking across all time periods. ALD recipients resume smoking early post-LTX, increase their consumption over time, and quickly become tobacco dependent. These data highlight an underrecognized serious health risk for these patients and demonstrate our need for more stringent clinical monitoring and intervention for tobacco use in the pre- and post-LTX periods. 相似文献
95.
Christopher L. Knight MD Henry A. Sakowski MD Bruce L. Houghton MD Mary B. Laya MD MPH Dawn E. DeWitt MD MSc 《Journal of general internal medicine》2004,19(5P2):594-598
The World Wide Web creates new challenges and opportunities for medical educators. Prominent among these are the lack of consistent standards by which to evaluate web-based educational tools. We present the instrument that was used to review web-based innovations in medical education submissions to the 2003 Society of General Internal Medicine (SGIM) national meeting, and discuss the process used by the SGIM web-based clinical curriculum interest group to develop the instrument. The 5 highest-ranked submissions are summarized with commentary from the reviewers. 相似文献
96.
Information about how Thai school-age children perceive fear is necessary for the development of culturally appropriate anxiety or fear measures. The purpose of this study was to describe Thai school-age children's perceptions of fear from their own perspective. Qualitative data from 13 Thai students in Grades 3 to 6 in three schools in Bangkok were obtained by semistructured, formal interviews, combined with drawings. The data were analyzed using content analysis within the frame of category development in the grounded theory method. Several culturally specific aspects of fear were revealed. This information is useful for health care providers caring for Thai children. The results of this study also illustrate the importance of carefully assessing children from culturally diverse backgrounds related to manifestations of anxiety or fear. 相似文献
97.
Expression profiling identifies the CRH/CRH-R1 system as a modulator of neurovascular gene activity.
Jan M Deussing Claudia Kühne Benno Pütz Markus Panhuysen Johannes Breu Mary P Stenzel-Poore Florian Holsboer Wolfgang Wurst 《Journal of cerebral blood flow and metabolism》2007,27(8):1476-1495
Corticotropin-releasing hormone receptor type 1 (CRH-R1)-deficient mice display reduced anxiety-like behavior, a chronic corticosterone deficit, and an impaired neuroendocrine stress response caused by disruption of the hypothalamic-pituitary-adrenocortical (HPA) axis. The molecular substrates and pathways of CRH/CRH-R1-dependent signaling mechanisms underlying the behavioral phenotype as well as the consequences of lifelong glucocorticoid deficit remain largely obscure. To dissect involved neuronal circuitries, we performed comparative expression profiling of brains of CRH-R1 mutant and wild-type mice using our custom made MPIP (Max Planck Institute of Psychiatry) 17k cDNA microarray. Microarray analysis yielded 107 genes showing altered expression levels when comparing CRH-R1 knockout mice with wild-type littermates. A significant proportion of differentially expressed genes was related to control of HPA and hypothalamic-pituitary-thyroid (HPT) axes reflecting not only the disturbance of the HPA axis in CRH-R1 mutant mice but also the interplay of both neuroendocrine systems. The spatial analysis of regulated genes revealed a prevalence for genes expressed in the cerebral microvasculature. This phenotype was confirmed by the successful cross-validation of regulated genes in CRH overexpressing mice. Analysis of the cerebral vasculature of CRH-R1 mutant and CRH overexpressing mice revealed alterations of functional rather than structural properties. A direct role of the CRH/CRH-R1 system was supported by demonstrating Crhr1 expression in the adult murine cerebral vasculature. In conclusion, these data suggest a novel, previously unknown role of the CRH/CRH-R1 system in modulating neurovascular gene expression and function. 相似文献
98.
99.
100.
Johannes Bjornsson John R. Goellner David Eugene Williams Mary V. Scheiber 《Journal of cancer research and clinical oncology》1986,111(3):289-290
Preoperative cytologic examinations were performed on bronchial material from 92 patients with postsurgical (pathologic) stage I (American Joint Committee) adenocarcinoma of the lung. All patients were followed up for at least 5 years or until death; thus, cases of adenocarcinoma metastatic to the lungs were virtually excluded. Only 22 patients (24%) had abnormal preoperative cytologic findings. This low cytologic sensitivity is ascribed to the small size and peripheral location of the tumors. Large lesions of high histologic grades were more likely to have positive preoperative cytologic findings than small, well-differentiated ones. 相似文献