全文获取类型
收费全文 | 9759篇 |
免费 | 923篇 |
国内免费 | 83篇 |
专业分类
耳鼻咽喉 | 81篇 |
儿科学 | 382篇 |
妇产科学 | 127篇 |
基础医学 | 1382篇 |
口腔科学 | 202篇 |
临床医学 | 1261篇 |
内科学 | 1931篇 |
皮肤病学 | 210篇 |
神经病学 | 792篇 |
特种医学 | 599篇 |
外科学 | 1242篇 |
综合类 | 266篇 |
一般理论 | 7篇 |
预防医学 | 1204篇 |
眼科学 | 127篇 |
药学 | 499篇 |
3篇 | |
中国医学 | 8篇 |
肿瘤学 | 442篇 |
出版年
2021年 | 119篇 |
2020年 | 72篇 |
2019年 | 130篇 |
2018年 | 139篇 |
2017年 | 131篇 |
2016年 | 105篇 |
2015年 | 150篇 |
2014年 | 171篇 |
2013年 | 306篇 |
2012年 | 361篇 |
2011年 | 392篇 |
2010年 | 293篇 |
2009年 | 273篇 |
2008年 | 396篇 |
2007年 | 387篇 |
2006年 | 377篇 |
2005年 | 367篇 |
2004年 | 320篇 |
2003年 | 263篇 |
2002年 | 308篇 |
2001年 | 307篇 |
2000年 | 299篇 |
1999年 | 264篇 |
1998年 | 226篇 |
1997年 | 242篇 |
1996年 | 191篇 |
1995年 | 166篇 |
1994年 | 164篇 |
1993年 | 166篇 |
1992年 | 219篇 |
1991年 | 217篇 |
1990年 | 227篇 |
1989年 | 227篇 |
1988年 | 213篇 |
1987年 | 201篇 |
1986年 | 211篇 |
1985年 | 209篇 |
1984年 | 147篇 |
1983年 | 123篇 |
1982年 | 108篇 |
1981年 | 110篇 |
1980年 | 97篇 |
1979年 | 80篇 |
1978年 | 93篇 |
1977年 | 76篇 |
1976年 | 87篇 |
1975年 | 65篇 |
1974年 | 74篇 |
1973年 | 59篇 |
1971年 | 68篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
J W Patterson H Konerding W M Kramer 《The Journal of dermatologic surgery and oncology》1987,13(10):1109-1114
An 87-year-old man with extensive solar damage presented with a 2-month history of a dome-shaped, crusted lesion on the dorsum of the left hand. Microscopically, the tumor consisted of fascicles of spindle cells with bizarre nuclei and clear, vacuolated cytoplasm. Histochemical, immunohistochemical, and ultrastructural features supported the diagnosis of atypical fibroxanthoma. There was no evidence of metastatic disease. The lesion was completely excised, and there has been no recurrence in 3 months of observation. This unusual "clear cell" variant of atypical fibroxanthoma must be distinguished from other clear cell tumors, such as metastatic renal cell carcinoma, clear cell eccrine carcinoma, and clear cell sarcoma (malignant melanoma) of soft parts. Although atypical fibroxanthoma is usually cured by complete surgical excision, metastases have been reported. 相似文献
72.
73.
A diffusion theory model of spatially resolved, steady-state diffuse reflectance for the noninvasive determination of tissue optical properties in vivo. 总被引:12,自引:0,他引:12
A model based upon steady-state diffusion theory which describes the radial dependence of diffuse reflectance of light from tissues is developed. This model incorporates a photon dipole source in order to satisfy the tissue boundary conditions and is suitable for either refractive index matched or mismatched surfaces. The predictions of the model were compared with Monte Carlo simulations as well as experimental measurements made with tissue simulating phantoms. The model describes the reflectance data accurately to radial distances as small as 0.5 mm when compared to Monte Carlo simulations and agrees with experimental measurements to distances as small as 1 mm. A nonlinear least-squares fitting procedure has been used to determine the tissue optical properties from the radial reflectance data in both phantoms and tissues in vivo. The optical properties derived for the phantoms are within 5%-10% of those determined by other established techniques. The in vivo values are also consistent with those reported by other investigators. 相似文献
74.
Patterson AH 《Bulletin of the American College of Surgeons》1990,75(4):13-15
The past 15 years have not been easy for the doctors who manage Medical Liability Mutual. There have been many frustrations and setbacks, and at times the predictors of doom for MLMIC seemed to be correct. Despite all the difficulties, the board of directors has never deviated from its original basic principles: (1) to attempt to settle meritorious claims rapidly and to resist totally those claims without merit; (2) to invest funds with caution and prudence, while achieving the best possible return on that investment; (3) to reduce medical injury and enhance patient safety; and (4) to make every effort to change a system that does not serve the public and threatens our health care system. The next five years may well be even more hectic than the past 15 have been. We do not know the reasons for the recent apparent improvement, and the situation may well deteriorate again. It is to be hoped that major changes that will benefit the public as a whole will occur, and that in the future the concerns of professional liability will not consume as much of our time and resources as they do at present. 相似文献
75.
76.
Heine RP McGregor JA Patterson E Draper D French J Jones W 《Infectious diseases in obstetrics and gynecology》1994,1(5):228-234
Objective: The objectives of this study were to 1) determine the prevalance and characterize the symptomatology of Trichomonas vaginalis (TV) infection in pregnant women on entry into prenatal care in an inner-city population; 2) compare conventional microscopic methods vs. culture techniques in diagnosing TV in both symptomatic and asymptomatic pregnant patients; and 3) correlate wet mount microscopic and microbiologic characteristics of varying manifestations of trichomoniasis.Methods: One thousand two hundred sixty patients in an inner-city population were tested at entry into prenatal care for TV by saline wet mount and culture techniques. Other tests for lower genital tract infection were also performed. Vaginal symptoms were ascertained through standardized questioning prior to examination. Standard microscopic and microbiologic data were also obtained for analysis. Wet mounts were systematically examined and considered negative if no TV was identified in 10 high powerfields (HPFs). Cultures were inspected from days 4 to 7 or until positive results were obtained. Results were analyzed using McNemar's test for correlated proportions, chi-squared test, or Fisher exact test where appropriate.Results: Culture and wet mount results were available in 1,175 patients. TV infection was documented by one or both techniques in 110/1,175 (9.4%). Culture methods detected 105/110 (94.5%) of all patients while wet mount detected 90/110 (73%) (P <0.001). Vaginal symptoms were present in only 20/110 patents (18.2%). Among asymptomatic patients, culture detected 94% while wet mount detected 70% (P < 0.001). Among symptomatic patients, wet mount and culture were both effective and diagnosed 85% and 95% of infections, respectively (P = not significant). Patients with TV were more likely to have increased vaginal fluid wlaite blood cells (WBCs) and more severe vaginal flora disruption than uninfected controls. Subgroup analysis revealed wet mount-positive/culture-positive patients were more likely to have vaginal flora disruption, as evidenced by decreased lactobacilli and elevated vaginal pH, than wet mount-negative/culture-positive subjects. Coexistent infection rates were similar regardless of wet mount status. Elevated vaginal fluid WBCs were more common among patients with symptoms.Conclusions: 1) Screening pregnant women for TV based solely on symptomatology is ineffective in this population; 2) culture techniques detected more infections than conventional microscopic evaluation; and 3) significant increases in vaginal fluid WBCs and altered vaginal flora are found in both symptomatic and asymptomatic TV, suggesting that both infestations have the potential to adversely affect pregnancy outcome. Studies on the influence of TV on pregnancy outcomes are ongoing. 相似文献
77.
Pam McGrath Carla Patterson Patsy Yates Sue Treloar Brian Oldenburg Colleen Loos 《The Australian journal of rural health》1999,7(1):34-42
The findings presented in this paper are part of a research project designed to provide a preliminary indication of the support needs of postdiagnosis women with breast cancer in remote and isolated areas in Queensland. This discussion will present data that focuses on the women's expressed personal concerns. For participants in this research a diagnosis of breast cancer involves a confrontation with their own mortality and the possibility of a reduced life span. This is a definite life crisis, creating shock and needing considerable adjustment. Along with these generic issues the participants also articulated significant issues in relation to their experience as women in a rural setting. These concerns centred around worries about how their partner and families cope during their absences for treatment, the additional burden on the family of having to cope with running the property or farm during the participant's absence or illness, added financial strain brought about by the cost of travel for treatment, maintenance of properties during absences, and problems created by time off from properties or self-employment. These findings accord with other reports of health and welfare services for rural Australian and the generic literature on psycho-oncology studies of breast cancer. 相似文献
78.
Successful management of unexplained coma by telemedicine 总被引:2,自引:0,他引:2
79.
User satisfaction with realtime teleneurology 总被引:3,自引:0,他引:3
User satisfaction (i.e. that of patients, medical staff at a remote hospital and medical staff at a neurological centre) with realtime teleneurology consultations was studied prospectively. Twenty-five patients with neurological problems admitted to a hospital without permanent neurological cover were assessed from a neurological centre by specialist neurologists using realtime video-links transmitting at 384 kbit/s. All users reported high levels of satisfaction with the technical aspects of the consultations. Patients, almost universally, reported confidence in teleneurology as a means of dealing with their presenting complaints. Similarly, medical staff at either site felt confident in managing patients using teleneurology and almost always felt that a telephone consultation would not have achieved as good an outcome. No major organizational problems were identified. These findings suggest overall user satisfaction with realtime teleneurology for managing patients with neurological problems admitted to hospitals that do not have resident neurologists. 相似文献
80.
Restenosis following successful percutaneous coronary revascularization continues to represent a major problem limiting the clinical efficacy of this procedure. The underlying mechanisms of restenosis are comprised of a combination of effects from vessel recoil, negative vascular remodeling, thrombus formation and neointimal hyperplasia. Indeed, there are important interactions among all of these mechanisms. For example, neointimal hyperplasia is stimulated by growth factors, which are released by local thrombi and the injured arterial segment itself, and act to enhance the expression of other growth-regulating proteins, in particular "second messengers", proto-oncogenes and other cell cycle controlling proteins. This results in an inflammatory and myofibroproliferative response, which may worsen vessel narrowing caused by recoil and result in the formation of a clinically significant restenotic lesion. A multitude of pharmacologic trials have been conducted in an attempt to prevent restenosis, but most have demonstrated little benefit. Studies in smaller numbers of patients have suggested a potential benefit for several classes of agents, including: 1) the antiproliferatives, angiopeptin, trapidil and tranilast; 2) selective elimination or alteration of proliferating cells; 3) enhancement of natural growth inhibitors; and 4) signal transduction blockade or inhibition of the gene expression for various growth-stimulating proteins. Finally, there have been advances in related areas, including development of antithrombotic catheters, novel polymers, and more efficient methods for transferring genes into the vessel wall. All of these offer the possibility of delivering agents (drugs, genes, or antisense oligonucleotides) locally at the site of intervention in a way that may optimize antiproliferative effects while minimizing systemic effects--ultimately leading to a more specific inhibition of the restenosis process. 相似文献