全文获取类型
收费全文 | 3005篇 |
免费 | 218篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 37篇 |
儿科学 | 128篇 |
妇产科学 | 101篇 |
基础医学 | 356篇 |
口腔科学 | 26篇 |
临床医学 | 410篇 |
内科学 | 590篇 |
皮肤病学 | 49篇 |
神经病学 | 229篇 |
特种医学 | 59篇 |
外科学 | 389篇 |
综合类 | 36篇 |
一般理论 | 1篇 |
预防医学 | 353篇 |
眼科学 | 50篇 |
药学 | 156篇 |
中国医学 | 10篇 |
肿瘤学 | 247篇 |
出版年
2023年 | 14篇 |
2022年 | 16篇 |
2021年 | 61篇 |
2020年 | 26篇 |
2019年 | 60篇 |
2018年 | 60篇 |
2017年 | 54篇 |
2016年 | 57篇 |
2015年 | 69篇 |
2014年 | 81篇 |
2013年 | 133篇 |
2012年 | 181篇 |
2011年 | 188篇 |
2010年 | 108篇 |
2009年 | 105篇 |
2008年 | 159篇 |
2007年 | 186篇 |
2006年 | 192篇 |
2005年 | 197篇 |
2004年 | 166篇 |
2003年 | 155篇 |
2002年 | 155篇 |
2001年 | 56篇 |
2000年 | 52篇 |
1999年 | 42篇 |
1998年 | 38篇 |
1997年 | 23篇 |
1996年 | 34篇 |
1995年 | 21篇 |
1994年 | 19篇 |
1993年 | 22篇 |
1992年 | 32篇 |
1991年 | 30篇 |
1990年 | 27篇 |
1989年 | 21篇 |
1988年 | 19篇 |
1987年 | 28篇 |
1986年 | 32篇 |
1985年 | 20篇 |
1984年 | 22篇 |
1983年 | 15篇 |
1981年 | 17篇 |
1979年 | 24篇 |
1978年 | 18篇 |
1977年 | 19篇 |
1976年 | 15篇 |
1975年 | 16篇 |
1974年 | 21篇 |
1973年 | 18篇 |
1970年 | 15篇 |
排序方式: 共有3227条查询结果,搜索用时 15 毫秒
1.
In this study we consider the process of the clinical encounter, and present exemplars of how assumptions of both clinicians and their patients can shift or transform in the course of a diagnostic interview. We examine the process as it is recalled, and further elaborated, in post-diagnostic interviews as part of a collaborative inquiry during reflections with clinicians and patients in the northeastern United States. Rather than treating assumptions by patients and providers as a fixed attribute of an individual, we treat them as occurring between people within a particular social context, the diagnostic interview. We explore the diagnostic interview as a landscape in which assumptions occur (and can shift), navigate the features of this landscape, and suggest that our examination can best be achieved by the systematic comparison of views of the multiple actors in an experience-near manner. We describe what might be gained by this shift in assumptions and how it can make visible what is at stake for clinician and patient in their local moral worlds—for patients, acknowledgment of social suffering, for clinicians how assumptions are a barrier to engagement with minority patients. It is crucial for clinicians to develop this capacity for reflection when navigating the interactions with patients from different cultures, to recognize and transform assumptions, to notice ‘surprises’, and to elicit what really matters to patients in their care. 相似文献
2.
3.
B I Sparks 《Journal of the American Optometric Association》1990,61(6):471-473
The purpose of the study was to determine if optometry students who completed an externship at a military facility were influenced for or against future enlistment considerations. The responses of 62 students were evaluated over a period of 3 years using an original self-completion questionnaire. The results suggest that while the majority of students left their externship with a positive attitude toward the military practice of optometry, factors such as low salaries and lagging promotional considerations influenced most to overlook the military as a practice option. The important ramifications of the study, as well as potential threats to its validity, are discussed. 相似文献
4.
Andrew G. Sparks Hsi-Han Yeh Siva S. Banda 《Optimal control applications & methods.》1990,11(4):307-325
This paper introduces a design methodology for a dynamic compensator that simultaneously minimizes the upper bound of a quadratic performance index and the H∞-norm of a disturbance transfer function matrix of a multiple-input/multiple-output system whose model contains parameter uncertainty in the state and input matrices. The real parameter uncertainty is modelled as additional measurement outputs and as additional weights on the existing noise inputs and measurement outputs of the system. The compensator equations are derived by taking the dual of a system with parameter variation in the state and output matrices, for which the compensator equations have previously been derived, and then taking the dual of the compensator equations. An algorithm for applying this theory is given and an example is shown. 相似文献
5.
6.
PURPOSE: The change/no-change procedure (J. E. Sussman & A. E. Carney, 1989), which assesses speech discrimination, has been used under the assumption that the number of stimulus presentations does not influence performance. Motivated by the tenets of the multiple looks hypothesis (N. F. Viemeister & G. H. Wakefield, 1991), work by R. F. Holt and A. E. Carney (2005) called this assumption into question (at least for adults): Nonsense syllable discrimination improved with more stimulus presentations. This study investigates the nature of developmental differences and the effects of multiple stimulus presentations in the change/no-change procedure. METHOD: Thirty normal-hearing children, ages 4.0-5.9 years, were tested on 3 consonant-vowel contrasts at various signal-to-noise ratios using combinations of 2 and 4 standard and comparison stimulus repetitions. RESULTS: Although performance fell below that which is predicted by the multiple looks hypothesis in most conditions, discrimination was enhanced with more stimulus repetitions for 1 speech contrast. The relative influence of standard and comparison stimulus repetitions varied across the speech contrasts in a manner different from that of adults. CONCLUSION: Despite providing no additional sensory information, multiple stimulus repetitions enhanced children's discrimination of 1 set of nonsense syllables. The results have implications for models of developmental speech perception and assessing speech discrimination in children. 相似文献
7.
8.
Kim Mudd Mary Elizabeth Bollinger Van Doren Hsu Michele Donithan Arlene Butz 《The Journal of asthma》2006,43(8):597-600
Background. Medication adherence impacts healthcare utilization. Pharmacy records are useful to establish fill patterns. Objective. Use pharmacy records to establish medication patterns fill patterns for comparison to healthcare utilization. Methods. Pharmacy records of 175 children with persistent asthma were collected and compared to healthcare utilization. Results. Majority of subjects had significant healthcare utilization, low numbers of rescue medications, and poor controller medication fill rates. Those with more rescue medications had more healthcare utilization and more controller medications. Conclusions. Pharmacy fill patterns demonstrate few rescue and/or controller medication fills. Those with more rescue medications reported increased healthcare utilization despite controller medications. 相似文献
9.
Alfred S. Friedman Samuel Granick Cheryl Kreisher Arlene Terras 《The American journal on addictions / American Academy of Psychiatrists in Alcoholism and Addictions》1993,2(3):232-237
This “matching” study attempts to determine characteristics of adolescent drug abuse patients that may determine whether an inpatient or an outpatient treatment setting will be more effective or more suitable for meeting the needs of the patient. Compared to short-term inpatient treatment, long-term outpatient treatment was shown to have significantly greater effect in reducing substance use/abuse for patients who had relatively more severe social lifestyle problems, family problems, and employment problems. Outpatient treatment even showed a trend toward a significantly better outcome for patients with more severe psychiatric problems. 相似文献
10.
Use of triple-lumen subclavian catheters for administration of total parenteral nutrition. 总被引:1,自引:0,他引:1
N Clark-Christoff V A Watters W Sparks P Snyder J P Grant 《JPEN. Journal of parenteral and enteral nutrition》1992,16(5):403-407
This study evaluated the safety of triple vs single-lumen catheters in intravenous nutrition. Patients who were judged likely to benefit from a triple-lumen catheter were randomized to receive either a single-lumen catheter, with additional peripheral or central venous access as needed, or a triple-lumen catheter. All patients were at increased risk of catheter-related infection because of one or more of the following conditions: > 60 years of age, breakdown of skin integrity, severe underlying illness, diagnosis of acute pancreatitis, recent head or neck surgery, or presence of a preexisting infection. Patients were excluded who had neutropenia, were immunosuppressed, had body burns > 40%, or had contaminated wounds in the subclavicular area. Of 204 patients entered between June 1989 and November 1991, 177 completed the required > or = 7 days of therapy. Seventy-eight of these patients were randomized to a single-lumen catheter and 99 to a triple-lumen catheter. Catheters were inserted and maintained by the Nutrition Support Team. Dressings were monitored daily and changed weekly using a bio-occlusive dressing. When parameters were met for a possible septic episode, simultaneous peripheral and central catheter blood cultures were obtained using the Isolator method. Catheter-related sepsis was considered present if the colony count from a central catheter lumen was > or = 5 times that of the peripheral blood. The incidence of catheter-related sepsis for single-lumen catheters was 2.6% (2 of 78) compared with 13.1% for triple-lumen catheters (13 of 99) (p < .01). No correlation was found with the number of insertion attempts, catheter days, or patient's age.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献