全文获取类型
收费全文 | 5288篇 |
免费 | 142篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 105篇 |
儿科学 | 55篇 |
妇产科学 | 1703篇 |
基础医学 | 342篇 |
口腔科学 | 21篇 |
临床医学 | 317篇 |
内科学 | 496篇 |
皮肤病学 | 694篇 |
神经病学 | 516篇 |
特种医学 | 67篇 |
外科学 | 448篇 |
综合类 | 27篇 |
预防医学 | 233篇 |
眼科学 | 41篇 |
药学 | 99篇 |
中国医学 | 4篇 |
肿瘤学 | 265篇 |
出版年
2018年 | 54篇 |
2016年 | 43篇 |
2015年 | 54篇 |
2014年 | 77篇 |
2013年 | 80篇 |
2012年 | 198篇 |
2011年 | 168篇 |
2010年 | 88篇 |
2009年 | 77篇 |
2008年 | 166篇 |
2007年 | 157篇 |
2006年 | 169篇 |
2005年 | 176篇 |
2004年 | 114篇 |
2003年 | 116篇 |
2002年 | 98篇 |
2001年 | 58篇 |
2000年 | 53篇 |
1999年 | 41篇 |
1987年 | 37篇 |
1975年 | 71篇 |
1973年 | 66篇 |
1971年 | 68篇 |
1969年 | 51篇 |
1967年 | 68篇 |
1965年 | 54篇 |
1964年 | 55篇 |
1963年 | 54篇 |
1961年 | 54篇 |
1959年 | 63篇 |
1957年 | 64篇 |
1955年 | 109篇 |
1954年 | 81篇 |
1942年 | 90篇 |
1938年 | 80篇 |
1936年 | 63篇 |
1935年 | 45篇 |
1933年 | 71篇 |
1931年 | 112篇 |
1930年 | 100篇 |
1929年 | 150篇 |
1928年 | 155篇 |
1927年 | 119篇 |
1926年 | 189篇 |
1925年 | 151篇 |
1924年 | 128篇 |
1923年 | 125篇 |
1922年 | 209篇 |
1912年 | 48篇 |
1889年 | 40篇 |
排序方式: 共有5433条查询结果,搜索用时 328 毫秒
61.
Shirley Musich Shaohung S. Wang Joann Ruiz Kevin Hawkins Ellen Wicker 《Geriatric nursing (New York, N.Y.)》2018,39(2):162-169
The purpose of this study was to stratify an older adult population for subsequent interventions based on functional ability, and to estimate prevalence, characteristics and impact of mobility limitations on health outcomes. In 2016, surveys were sent to a stratified random sample of AARP® Medicare Supplement insureds; mobility limitations were defined using two screening questions. Responses were stratified to three mobility limitation levels. Multivariate regression models determined characteristics and impact on health outcomes. Among weighted survey respondents (N = 15,989), severe, moderate and no limitation levels were 21.4%, 18.4% and 60.3%, respectively. The strongest predictors of increased limitations included pain and poor health. Individuals with more severe limitations had increased falls, decreased preventive services compliance and increased healthcare utilization and expenditures. Utilizing two screening questions stratified this population to three meaningful mobility limitation levels. Higher levels of mobility limitations were strongly associated with negative health outcomes. Mobility-enhancing interventions could promote successful aging. 相似文献
62.
63.
Joann Spinale Scott D. Cohen Prashant Khetpal Rolf A. Peterson Brenna Clougherty Christina M. Puchalski Samir S. Patel Paul L. Kimmel 《Clinical journal of the American Society of Nephrology》2008,3(6):1620-1627
Background and objectives: No studies have evaluated the relationship among spirituality, social support, and survival in patients with ESRD. This study assessed whether spirituality was an independent predictor of survival in dialysis patients with ESRD after controlling for age, diabetes, albumin, and social support.Design, setting, participants, & measurements: A total of 166 patients who had ESRD and were treated with hemodialysis completed questionnaires on psychosocial variables, quality of life, and religious and spiritual beliefs. The religious variables were categorized into three scores on a 0 to 20 scale (low to high levels): Spirituality, religious involvement, and religion as coping. Social support was assessed using the Multidimensional Scale for Perceived Social Support. Analyses were also performed including and excluding patients with HIV infection. Religious variables were categorized on the basis of means, medians, and tertiles.Results: In analyses that used religious variables, only the responses on the spirituality scale split at the mean were associated with survival. The association of other religious variables with survival did not reach significance. Social support correlated with spirituality, religion as coping, and religious involvement measures. Only social support and age were associated with survival when controlling for diabetes, albumin concentration, HIV infection, and spirituality.Conclusions: These data suggest that the effects of spirituality may be mediated by social support. Larger, multicenter, prospective studies that use well-validated tools to measure religiosity and spirituality are needed to determine whether there is an independent association of spirituality variables with survival in patients with ESRD.Relationships between spirituality and mortality have been investigated in medical populations but remain controversial (1–13). Variable associations have been found depending on definitions of spirituality and patient populations studied (1–11). Miller and Thoreson (12) explored nine different hypotheses regarding the relationship among religious beliefs, spirituality, and mortality. The only hypothesis that they found to be supported by persuasive evidence stated that “church/service attendance protects [only] healthy people against death.” Studies supporting a similar link in patients with chronic illnesses have also shown mixed results. Koenig et al. (14) evaluated approximately 4000 elderly patients to determine whether attendance at religious services during a 6-yr period was associated with survival. In adjusted analyses, there was a significantly lower mortality in patients who frequently attended church services.Many researchers have suggested a publication bias, whereby only the studies that indicate a significant relationship are published (13). Most studies cited the need for more research on the relationship between spirituality and mortality before any firm conclusions can be reached. In addition, the health dimensions of lack of belief have not been well explored.There also exists considerable debate on how to operationalize religiosity and spirituality. Whereas the first term often is associated with participation in social institutions and adherence to specific beliefs and practices, the latter is a broader term that typically pertains to life''s vital qualities and an overall broad belief in the immaterial features of life (12). Spirituality relates to transcendent values and relationships and the way people find meaning, purpose, and hope in life and in the midst of suffering (15). A person may be spiritual and not religiously observant or observe rituals without a spiritual focus.Few studies have specifically evaluated the potential association between spirituality and survival in patients with ESRD (16,17). We (18) previously showed that religious and spiritual beliefs are associated with decreased perception of burden of illness, decreased depressive affect, increased perception of social support, and higher satisfaction with life and perception of quality of life in an urban, predominantly black ESRD population. We also found that a “spiritual beliefs scale” correlated with several quality-of-life measures in patients with ESRD (19). Even though many of these psychosocial measures have been shown to be related to survival independently, no study to our knowledge has demonstrated a link between spirituality and survival in this population.We determined whether three variables related to spirituality, religious beliefs, and practices and faith (spirituality, religious involvement, and religion as a coping measure) were independently associated with survival in hemodialysis patients with ESRD. We then assessed the relationship between social support and survival, regardless of whether the spiritual variables were included in analyses. We hypothesized that spiritual variables would be associated with survival in patients with ESRD. 相似文献
64.
Cytokine-induced nitric oxide inhibits mitochondrial energy production and induces myocardial dysfunction in endotoxin-treated rat hearts 总被引:2,自引:0,他引:2
Tatsumi T Akashi K Keira N Matoba S Mano A Shiraishi J Yamanaka S Kobara M Hibino N Hosokawa S Asayama J Fushiki S Fliss H Nakagawa M Matsubara H 《Journal of molecular and cellular cardiology》2004,37(3):775-784
The mechanism responsible for cardiac depression in septic shock remains unknown. The present study examined whether nitric oxide (NO) overproduced by inducible NO synthase (iNOS) can inhibit aerobic energy metabolism and impair the myocardial function in endotoxin-treated rat hearts. Lipopolysaccharide (LPS) significantly decreased systolic blood pressure (BP) to 44% of control during the 48 h treatment. Hearts from control and LPS-treated rats were perfused in a Langendorff apparatus. After LPS injection, left ventricular (LV) developed pressure (LVDP) was significantly depressed, plasma NO2-/NO3- (NO(x)) concentration was markedly increased, and myocardial adenosine 5'-triphosphate (ATP), creatine phosphate (CrP), and the ratio of ATP/adenosine 5'-diphosphate were progressively decreased with time. Immunological examination showed a significant expression of iNOS protein in the LPS-treated myocytes. Aminoguanidine, an inhibitor of iNOS, significantly attenuated these LPS-induced functional and metabolic changes. Myocardial cyclic guanosine 3',5'-monophosphate (cGMP) content was significantly increased after LPS injection. Methylene blue, an inhibitor of soluble guanylate cyclase, blunted this increase in cGMP and significantly restored the LPS-induced contractile dysfunction 6 h after LPS injection. In addition, there was a significant negative correlation between LVDP and myocardial cGMP levels as well as a significant negative correlation between LVDP and plasma NO(x) levels. In contrast, 48 h after LPS injection, methylene blue no longer affected cardiac performance, and there was a significant positive correlation between LVDP and myocardial ATP content. Furthermore, the normalized activities (as a ratio of the citrate synthase activity) of mitochondrial NADH-CoQ reductase, succinate-CoQ reductase, and ATPase, were significantly inhibited, and the swelling or disruption of mitochondria cristae was seen in the 48 h LPS treatment. These LPS-induced functional and morphological disorders in the mitochondria were significantly improved by aminoguanidine. The findings suggest that sustained production of NO by iNOS leads to contractile dysfunction via cGMP in the early stage, but that it can directly impair the mitochondrial function, lower myocardial energy production, and contribute significantly to the myocardial dysfunction in the later stage of septic shock. 相似文献
65.
Katherina N.-L. Flaig Steven E. Mock Joann P. Reinhardt 《European journal of ageing》2008,5(3):215-222
This study draws on an evolutionary model of exchange in relationships to examine the nature of perceived reciprocity in the
context of kin and non-kin relationships among a sample of visually impaired older adults (age 63–99). Further, we examined
the direct and moderating impact of functional impairment and adaptation to visual impairment on the nature of perceived reciprocity.
Results showed that the greater the degree of genetic relatedness the more imbalanced the exchange. It was also found that
degree of adaptation to visual impairment moderated the association between genetic relatedness and perceived exchange, such
that the greater the degree of genetic relatedness the more people reported they gave rather than received except at very
low levels of adaptation, when people received more than they gave the greater the degree of genetic relatedness. Thus, an
evolutionary model was supported such that imbalanced exchange was found more with greater degrees of genetic relatedness,
but the direction of exchange was different for high versus low levels of adaptation to vision impairment. 相似文献
66.
67.
Elisabeth Vodicka Roanne Mejilla Suzanne G Leveille James D Ralston Jonathan D Darer Tom Delbanco Jan Walker Joann G Elmore 《Journal of medical Internet research》2013,15(9)
Background
Offering patients online access to medical records, including doctors’ visit notes, holds considerable potential to improve care. However, patients may worry about loss of privacy when accessing personal health information through Internet-based patient portals. The OpenNotes study provided patients at three US health care institutions with online access to their primary care doctors’ notes and then collected survey data about their experiences, including their concerns about privacy before and after participation in the intervention.Objective
To identify patients’ attitudes toward privacy when given electronic access to their medical records, including visit notes.Methods
The design used a nested cohort study of patients surveyed at baseline and after a 1-year period during which they were invited to read their visit notes through secure patient portals. Participants consisted of 3874 primary care patients from Beth Israel Deaconess Medical Center (Boston, MA), Geisinger Health System (Danville, PA), and Harborview Medical Center (Seattle, WA) who completed surveys before and after the OpenNotes intervention. The measures were patient-reported levels of concern regarding privacy associated with online access to visit notes.Results
32.91% of patients (1275/3874 respondents) reported concerns about privacy at baseline versus 36.63% (1419/3874 respondents) post-intervention. Baseline concerns were associated with non-white race/ethnicity and lower confidence in communicating with doctors, but were not associated with choosing to read notes or desire for continued online access post-intervention (nearly all patients with notes available chose to read them and wanted continued access). While the level of concern among most participants did not change during the intervention, 15.54% (602/3874 respondents, excluding participants who responded “don’t know”) reported more concern post-intervention, and 12.73% (493/3874 respondents, excluding participants who responded “don’t know”) reported less concern.Conclusions
When considering online access to visit notes, approximately one-third of patients had concerns about privacy at baseline and post-intervention. These perceptions did not deter participants from accessing their notes, suggesting that the benefits of online access to medical records may outweigh patients’ perceived risks to privacy. 相似文献68.
69.
Reem Z. Sharaiha Kaveh Hajifathalian Rekha Kumar Katherine Saunders Amit Mehta Bryan Ang Daniel Skaf Shawn Shah Andrea Herr Leon Igel Qais Dawod Enad Dawod Kartik Sampath David Carr-Locke Robert Brown David Cohen Andrew J. Dannenberg Srihari Mahadev Louis J. Aronne 《Clinical gastroenterology and hepatology》2021,19(5):1051-1057.e2