首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   221篇
  免费   11篇
  国内免费   3篇
耳鼻咽喉   1篇
儿科学   13篇
基础医学   22篇
口腔科学   5篇
临床医学   23篇
内科学   53篇
皮肤病学   10篇
神经病学   18篇
特种医学   26篇
外科学   12篇
综合类   6篇
预防医学   20篇
药学   11篇
肿瘤学   15篇
  2021年   2篇
  2020年   5篇
  2019年   4篇
  2018年   6篇
  2017年   4篇
  2016年   4篇
  2015年   6篇
  2014年   7篇
  2013年   12篇
  2012年   10篇
  2011年   9篇
  2010年   7篇
  2009年   10篇
  2008年   7篇
  2007年   10篇
  2006年   5篇
  2005年   3篇
  2004年   4篇
  2003年   5篇
  2002年   5篇
  2001年   2篇
  2000年   3篇
  1999年   3篇
  1998年   9篇
  1997年   11篇
  1996年   5篇
  1995年   11篇
  1994年   6篇
  1993年   5篇
  1992年   4篇
  1991年   1篇
  1990年   2篇
  1989年   4篇
  1988年   8篇
  1987年   3篇
  1986年   1篇
  1985年   4篇
  1984年   4篇
  1983年   4篇
  1982年   5篇
  1981年   3篇
  1980年   1篇
  1978年   1篇
  1977年   1篇
  1976年   2篇
  1973年   1篇
  1967年   2篇
  1947年   1篇
  1945年   1篇
  1942年   1篇
排序方式: 共有235条查询结果,搜索用时 15 毫秒
71.
72.
73.
Purpose

To evaluate the concurrent validity of the PROMIS Pediatric Global Health measure (PGH-7), child-report and parent-proxy versions.

Methods

Surveys were administered via home computer on two separate occasions (December, 2011 and August/September, 2012) to a convenience sample of 4636 children 8–17 years old and 2609 parents who participated in a national Internet panel. Data analysis included: (1) evaluations of differences in PGH-7 scores between groups defined by sociodemographics, clinical characteristics, and access to health care; (2) associations with 15 PROMIS pediatric measures; and (3) correlations with two health-related quality-of-life instruments, the KIDSCREEN-10 and PedsQL-15.

Results

PGH-7 scores were lower for children with chronic conditions, Hispanic ethnicity, low socioeconomic status, and barriers to accessing health care. The PGH-7 showed excellent convergent and discriminant validity with PROMIS pediatric measures of physical, mental, and social health. The PGH-7 was strongly correlated with the KIDSCREEN-10, which assesses positive health, and moderately correlated with the PedsQL-15, which assesses problems with a child’s health.

Conclusions

The PGH-7 measures global health, summarizing a child’s physical, mental, and social health into a single score. These properties make it a useful clinical, population health, and research tool for applications that require an efficient, precise, and valid summary measure of a children’s self-reported health status. Future research should prospectively evaluate the PGH-7’s capacity to detect change that results from alterations in clinical status, transformations of the healthcare delivery system, and children’s health development.

  相似文献   
74.
Bevans MF 《Blood》2011,118(17):4506-4507
  相似文献   
75.
BACKGROUND: Undesirable hair growth presents a significant problem for many patients, and photoepilation has become a very popular procedure in aesthetic and cosmetic practice. Among the systems used are the long‐ and short‐pulsed alexandrite lasers (LP‐Alex, SP‐Alex) and intense pulsed light (IPL) sources. The present study retrospectively examined the outcome of these systems from the viewpoint of efficacy and side effects.

PATIENTS AND METHODS: Three hundred and eighty‐nine patients (370 females and 19 males, mean age 36.4?yrs, skin types II–V) were admitted to the study, with a total of 532 treated sites. They were treated either with the LP‐Alex, SP‐Alex or IPL. Subjective evaluation and interview of the patients was held prior to every treatment session. Six to eight treatments were required with the alexandrite lasers, 2.4–2.8 months between treatments, and the IPL source required 8–9 treatments, 2–2.5 months apart.

RESULTS: No significant difference was seen between the LP‐ and SP‐Alex, or between both of them and the IPL source, although the period to regrowth was longer for the lasers. Erythema and oedema were more noticeable with the LP‐Alex, as were crusting and hyper‐ and hypopigmentation. Discomfort was greatest with the LP‐Alex and the IPL source. Hair induction at the borders of the treated area on the face and neck was seen only with the LP‐Alex, and correlated statistically significantly with any episode of severe erythema, crusting or hyperpigmentation.

CONCLUSIONS: There was no statistically significant difference between the LP‐, SP‐Alex and IPL photoepilation with regard to efficacy. Transient side effects were highest with the LP‐Alex, and least with the IPL system. In the LP‐Alex treated face and neck sites, 3.1% had hair induction in the borders of the treated areas.  相似文献   
76.
BACKGROUND: To enhance the impact of school nutrition programs on children's health, more information is needed on the associations between healthy and unhealthy food offerings during school lunch periods and children's eating behavior. The purpose of this study is to evaluate the contributions of food offerings and participation in school lunch programs on children's overall (both in‐ and out‐of‐school) eating behavior. METHODS: A cross‐sectional observational study was conducted in which 2039 students in 12 elementary and 10 middle schools reported their eating behavior and the frequencies with which they purchased meals and à la carte items in the school cafeteria. Food service managers from each school provided information on the availability of foods and beverages during school lunch periods. Multilevel regression analyses were conducted to identify school‐ and student‐level predictors of children's eating behavior. RESULTS: The availability of nutritious foods during school lunch periods was associated with healthier eating behavior among students. However, this effect was observed only among children who infrequently purchased à la carte food items, and not among those who were frequent purchasers. CONCLUSION: Increased availability of fruits, vegetables, whole grains, and low‐fat dairy products as components of school meals may be an effective strategy to promote healthy eating behaviors among children. Improving the nutrition standards for foods offered in competition with federally reimbursable school meals may enhance the positive effects of school meal programs on student eating behavior.  相似文献   
77.
Objective   To estimate the population-based incidence of erythromelalgia.
Background   Only one report describing the incidence of erythromelalgia has been published previously.
Study design   A population-based analysis of data from the Rochester Epidemiology Project.
Setting    Tertiary care medical centre in Olmsted County, Minnesota (a rural county in the south-eastern portion of the state).
Patients   Thirty-three residents of Olmsted County with a diagnosis of erythromelalgia during the study period.
Methods   Age- and sex-specific incidence rates of erythromelalgia were determined.
Intervention   None.
Main outcome   Population-based incidence rate.
Results   The overall age- and sex-adjusted incidence rate (95% confidence interval, 95% CI) was 1.3 (0.8–1.7) per 100 000 people per year. The incidence of primary and secondary erythromelalgia was 1.1 (0.7–1.5) and 0.2 (0.02–0.4) per 100 000 people per year, respectively. The age-adjusted incidence rates (95% CI) were 2.0 (1.2–2.7) per 100 000 women and 0.6 (0.1–1.1) per 100 000 men. The study was limited by the small sample size and potential variability in recognition of erythromelalgia.
Conclusion   The population-based incidence of erythromelalgia has increased with each decade in Olmsted County over the past three decades; overall incidence was 1.3 per 100 000 people per year, approximately 5 times higher than previously reported.  相似文献   
78.
We administered a combination of rubidazone, cytosine arabinoside, vincristine, and prednisone (ROAP) to 91 patients with acute myelogenous leukemia who were 50 yr of age or older. These patients had been identified in previous studies to be a group with a relatively poor prognosis. One-third of the patients had an antecedent hematologic disorder prior to treatment. Forty patients (48%) obtained a complete hematologic and clinical remission. A history of an antecedent hematologic disorder, male sex, and absence of Auer rods were adverse factors for achieving remission in this older population. More than half of the patients achieved remission in one course. The major cause of failure to obtain a remission was death due to infection, 40% of which were caused by fungi. Resistance to chemotherapy, although uncommon, was noted more frequently in patients with an antecedent hematologic disorder. Univariate and multivariate prognostic factor analysis was used to compare these patients with a historical control group treated with a program in which adriamycin was used instead of rubidazone (AdOAP). No significant difference in remission rate was detected. Cyclocytidine was used as a maintenance agent in this study, and while the median remission duration was only 37 wk, 30% of patients are expected to be in remission for 2 yr. Chemotherapy programs combining an anthracycline with cytosine arabinoside, given to older patients in similar fasion to younger patients will achieve remissions in one-half of a group of older patients. These remissions are of comparable quality to those of younger patients. Mathematical models derived from analysis of prognostic factors are of use in identifying patients likely to fail these programs who are in need of innovative approaches to treatment.  相似文献   
79.
Pryzwansky  KB; Wyatt  TA; Nichols  H; Lincoln  TM 《Blood》1990,76(3):612-618
The presence and physiologic role of cyclic GMP-dependent protein kinase (G-kinase) in human neutrophils was investigated by Western blot analysis and immunocytochemistry. Small quantities of G-kinase were found in the cytoskeletal-enriched fraction of neutrophil lysates as detected by Western blots using a polyclonal antibody raised against bovine aorta G-kinase. Immunofluorescence microscopy demonstrated in adherent neutrophils that G-kinase was localized diffusely within the cytoplasm, at the microtubule organizing center, and in the euchromatin of the nucleus. Because cyclic GMP is implicated as a modulator of neutrophil chemotaxis, G-kinase localization was investigated in neutrophils activated with N-formyl-methionyl-leucyl-phenylalanine (fMLP). fMLP stimulated transient focal changes in G-kinase localization that coincided with transient changes in cell shape. G- kinase translocated over a period of 5 minutes from diffuse staining of the cytosol to filaments within the uropod of polarized cells (1 minute), to bundles of filaments associated with loss of cell polarity (2.5 minutes), and finally to more intense staining of the nuclear euchromatin (5 minutes). Optical sectioning of neutrophils by confocal laser scanning microscopy confirmed that G-kinase was restricted to specific sub-cellular compartments during cell activation. This transient localization of G-kinase was disrupted by cytoskeletal inhibitors and was augmented by 8-Br-cyclic GMP. These data provide evidence for the first time that G-kinase plays a physiologic role in human neutrophils, and support the concept of compartmentalization of cyclic nucleotides during neutrophil activation.  相似文献   
80.
Tumor burden in adult patients with acute leukemia is assessed using the percentage of blast cells in the bone marrow or blood. It is clear, however, that not all blast cells are leukemic cells, especially during rapid marrow regeneration. Similarly, some leukemia cell lines have been shown to differentiate in vitro, and the same process also occurs in vivo. Therefore, the leukemic burden may be due to more differentiated cells as well as to blast cells. The purpose of this study was to investigate whether the human malignancy-associated nucleolar antigen (HMNA) could be used as a marker for leukemic cells and to examine its potential as a diagnostic tool. The proportion of HMNA-positive cells in the bone marrow of patients with acute leukemia was determined by indirect immunofluorescence with antibodies to HMNA and was compared with the differential counts routinely made in the clinic laboratory. The percentages of HMNA-positive cells among the nucleated cells in the marrow of 72 patients with clinical evidence of leukemia were significantly higher (range 9%-98%, median 83%) than those observed for nonleukemic individuals (range less than 0.05%-2.5%, median 1%) or for fractions of marrow cells from normal volunteers enriched for normal early progenitor cells (less than or equal to 2%). Patients with leukemia in remission had a lower percentage of HMNA- positive cells (range 0%-83%, median 3%). The percentage of HMNA- positive cells increased as patients approached relapse. Although the percentage of HMNA-positive cells was related to the percentage of blast cells in the bone marrow of the patients with leukemia, some partially differentiated cells were also HMNA-positive in some specimens, and some blastic cells were HMNA-negative in other specimens. These studies indicate the potential usefulness of HMNA as a marker for leukemic cells.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号