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   520篇
  免费   36篇
  国内免费   6篇
耳鼻咽喉   8篇
儿科学   31篇
妇产科学   4篇
基础医学   25篇
口腔科学   14篇
临床医学   55篇
内科学   131篇
皮肤病学   15篇
神经病学   7篇
特种医学   75篇
外科学   78篇
综合类   18篇
预防医学   32篇
眼科学   18篇
药学   15篇
中国医学   1篇
肿瘤学   35篇
  2023年   6篇
  2022年   11篇
  2021年   11篇
  2020年   12篇
  2019年   14篇
  2018年   15篇
  2017年   17篇
  2016年   19篇
  2015年   11篇
  2014年   28篇
  2013年   19篇
  2012年   19篇
  2011年   31篇
  2010年   18篇
  2009年   29篇
  2008年   21篇
  2007年   17篇
  2006年   11篇
  2005年   7篇
  2004年   8篇
  2003年   13篇
  2002年   6篇
  2001年   13篇
  2000年   8篇
  1999年   8篇
  1998年   16篇
  1997年   12篇
  1996年   20篇
  1995年   13篇
  1994年   13篇
  1993年   20篇
  1992年   20篇
  1991年   5篇
  1990年   5篇
  1989年   5篇
  1988年   11篇
  1987年   11篇
  1986年   7篇
  1985年   10篇
  1984年   2篇
  1983年   1篇
  1982年   5篇
  1981年   3篇
  1980年   4篇
  1979年   1篇
  1978年   1篇
  1977年   3篇
  1975年   2篇
排序方式: 共有562条查询结果,搜索用时 15 毫秒
31.
Paternal involvement in children's lives is associated with a variety of child outcomes, including improved cognition, improved mental health, reduced obesity rates, and asthma exacerbation. Given this evidence, the American Academy of Pediatrics has promoted actions by pediatricians to engage fathers in pediatric care. Despite these recommendations, the mother–child dyad, rather than the mother–father–child triad, remains a frequent focus of care. Furthermore, pediatric care is often leveraged to improve maternal health, such as screening for maternal depression, but paternal health is infrequently addressed even as men tend to exhibit riskier behaviors, poorer primary care utilization, and lower life expectancy. Therefore, increasing efforts by pediatric clinicians to engage fathers may affect the health of both father and child. These efforts to engage fathers are informed by currently used definitions and measures of father involvement, which are discussed here. Factors described in the literature that affect father involvement are also summarized, including culture and context; interpersonal factors; logistics; knowledge and self-efficacy; and attitudes, beliefs, and incentives. Innovative ways to reach fathers both in the clinic and in other settings are currently under investigation, including use of behavior change models, motivational interviewing, mobile technologies, peer support groups, and policy advocacy efforts. These modalities show promise in effectively engaging fathers and improving family health.  相似文献   
32.

Background

Pleomorphic liposarcoma (PL) is an exceedingly rare tumor of the head and neck. This aggressive liposarcoma variant portends a poorer prognosis compared to more typical sarcomatous tumors.

Methods

Multi-institutional study including two cases of PL, the first case occurring in the post-auricular region and the second in the cheek with later recurrence within the parotid bed.

Results

Both patients were treated surgically with wide local excision. One patient required reoperation to obtain negative margins. The other patient underwent a total parotidectomy with neck dissection for recurrent intraparotid nodal disease. Both patients underwent adjuvant radiotherapy. No patient had evidence of recurrent disease with minimum one year follow-up.

Conclusion

Although the literature is sparse on this disease, wide surgical extirpation with negative margins and adjuvant radiation is recommended. Increased reports of this pathology can be helpful in providing practitioners with experienced-based information that can aid in early detection and treatment. We present the first case series of PL of the head and neck in the literature.  相似文献   
33.

Purpose

To report the outcomes of 47 patients with temporal bone osteoradionecrosis treated primarily with surgical resection in order to analyze whether flap type and hyperbaric oxygen use affect wound breakdown.

Materials and methods

Between January 1998 and January 2016, 47 patients were treated for temporal bone osteoradionecrosis with surgery. Some patients were also treated with hyperbaric oxygen. Resection of grossly necrotic temporal bone was followed by immediate reconstruction with local, regional, or free flaps. Minimum follow-up was 6 months. If patients had breakdown of their initial reconstructions, secondary reconstruction was performed with either a regional or free flap. During the post-operative period, wound breakdown, flap complications, and patient survival were noted.

Results

30 patients developed ORN from primary radiotherapy while 17 had post-operative radiation. It was found that wound breakdown was significantly associated with type of flap reconstruction (p = 0.02) with local flap reconstruction portending a poorer prognosis. Hyperbaric oxygen was not associated with decreased wound breakdown (p = 0.5).

Conclusions

Surgical treatment can be an effective treatment for temporal bone osteoradionecrosis, without hyperbaric oxygen providing any additional benefit. Reconstruction with regional or free flaps may be a more reliable method to resurface defects compared to local flaps.  相似文献   
34.
Introduction

Nepal has pledged to substantially reduce maternal and newborn death by 2030. Improving quality of intrapartum health services will be vital to reduce these deaths. This paper examines quality of delivery and newborn services in health facilities of Nepal.

Methods

Data were sourced from the Nepal Health Facility Survey 2015, which covered a national representative sample of health facilities. The datasets were analysed to assess service readiness, availability and quality of delivery and newborn care in a sample of 992 health facilities.

Results

Of the 992 facilities in the sample, 623 provided delivery and newborn care services. Of the 623 facilities offering delivery and newborn care services, 13.3% offered comprehensive emergency obstetric care (CEmONC), 19.6% provided basic emergency obstetric care (BEmONC) and 53.9% provided basic delivery and newborn service. The availability of essential equipment for delivery and newborn care was more than 80% in health facilities. Except for the coverage of vitamin K injection, the coverage of immediate newborn care was more than 85% in all health facilities. The coverage of use of chlorhexidine ointment to all newborns was more than 70% in government hospitals and primary health care centers (PHCCs) and only 32.3% in private hospitals.

Conclusions

These findings show gaps in equipment and drugs, especially in PHCCs and private health facilities. Improving readiness and availability of equipment and drugs in PHCCs and private health facility will help improve the quality of care to further reduce maternal and newborn mortality in Nepal.

  相似文献   
35.
Background

Almost all preventable neonatal deaths take place in low- and middle-income countries and affect the poorest who have the least access to high quality health services. Cost of health care is one of the factors preventing access to quality health services and universal health coverage. In Nepal, the majority of expenses related to newborn care are borne by the caregiver, regardless of socioeconomic status. We conducted a study to assess the out of pocket expenditure (OOPE) for sick newborn care in hospitals in Nepal.

Methods

This cross-sectional study of hospital care for newborns was conducted in 11 hospitals in Nepal and explored OOPE incurred by caregivers for sick newborn care. Data were collected from the caregivers of the sick newborn on the topics of cost of travel, accommodation, treatment (drugs, diagnosis) and documented on a sick newborn case record form.

Results

Data were collected from 814 caregivers. Cost of caregivers’ stay accounted for more than 40% of the OOPE for sick newborn care, followed by cost of travel, and the baby’s stay and treatment. The overall OOPE ranged from 13.6 to 226.1 US dollars (USD). The median OOPE was highest for preterm complications ($33.2 USD; CI 14.0–226.1), followed by hyperbilirubinemia ($31.9 USD; CI 14.0–60.7), respiratory distress syndrome ($26.9 USD; 15.3–121.5), neonatal sepsis ($ 25.8 USD; CI 13.6–139.8) and hypoxic ischemic encephalopathy ($23.4 USD; CI 13.6–97.7).

Discussion for practice

In Nepal, OOPE for sick newborn care in hospitals varied by neonatal morbidity and duration of stay. The largest proportion of OOPE were for accommodation and travel. Affordable and accessible health care will substantially reduce the OOPE for sick newborn care in hospitals.

  相似文献   
36.
Purpose: The aim of this study was to determine the repeatability of high‐ and low‐contrast visual acuity (VA) measurements at near. Methods: Fifty‐five normal subjects were recruited. Inclusion criteria included visual acuity of at least 0.00 logarithm of minimum angle of resolution (logMAR) on each eye at distance. One eye was selected for this study, either the one with a better acuity or randomly chosen if there was no difference between the two eyes. Near VA was measured in a random order with the PolyU high‐contrast (PolyU‐HC), the PolyU low‐contrast (PolyU‐LC), the Precision high‐contrast (P‐HC) and the Precision low‐contrast (P‐LC) charts at 400 mm. Measurements were repeated after one to two weeks. Repeatability was presented using the 95% limits of agreement between visits. Results: The between‐visit repeatability was ±0.063 logMAR for high‐contrast and ±0.141 for low‐contrast using the PolyU charts. The between‐visit repeatability was ±0.120 logMAR for high‐contrast and ±0.110 for low‐contrast using the Precision charts. Seventeen subjects had high‐contrast VA better than ‐0.10 logMAR using Precision chart, which could not be measured by PolyU chart. The mean difference between high‐ and low‐contrast VA was 0.108 from the Precision charts (median difference of 0.10 or one line). Conclusions: The Precision charts could measure high‐contrast near VA to threshold level. Practitioners should be aware of a VA difference of more than one line in repetitive measurement, at both high and low contrast. A difference in near high‐ and low‐contrast VA of more than one line may warrant further investigation.  相似文献   
37.

Background

The prevalence of Metabolic Syndrome and related chronic diseases, among them non-insulin-dependent (type 2) diabetes mellitus, are on the rise in the United States and throughout the world. Animal models that respond to environmental stressors, such as diet, are useful for investigating the outcome and development of these related diseases.

Objective

Within this context, growth and energy relationships were characterized in the Nile rat, an exotic African rodent, as a potential animal model for diet-induced type 2 diabetes mellitus and Metabolic Syndrome.

Methods

Compiled data from several studies established the relationship between age, body weight gain (including abdominal adiposity), food and water consumption, and blood glucose levels as determinants of diabetes in male and female Nile rats. Glucose Tolerance Testing, insulin, HbA1c, blood pressure measurements and plasma lipids further characterized the diabetes in relation to criteria of the Metabolic Syndrome, while diet modification with high-fat, low-fiber or food restriction attempted to modulate the disease.

Results

The Nile rat fed lab chow demonstrates signs of the Metabolic Syndrome that evolve into diet-induced non-insulin-dependent (type 2) diabetes mellitus characterized by hyperinsulinemia with rising blood glucose (insulin resistance), abdominal adiposity, and impaired glucose clearance that precedes increased food and water intake, as well as elevated HbA1c, marked elevation in plasma triglycerides and cholesterol, microalbuminuria, and hypertension. Males are more prone than females with rapid progression to diabetes depending on the challenge diet. In males diabetes segregated into early-onset and late-onset groups, the former related to more rapid growth and greater growth efficiency for the calories consumed. Interestingly, no correlation was found between blood glucose and body mass index (overall adiposity) in older male Nile rats in long term studies, whereas blood glucose and the perirenal fat pad, as well as liver and kidney weight, were positively related to early-onset diabetes. Rats weaned early (4-5 wks) and challenged with a high-fat Western-type diet developed diabetes faster, and body fat accumulation was more apparent, whereas food restriction curtailed it.

Conclusion

The Nile rat fed typical rodent diets develops hyperinsulinemia that precedes hyperglycemia (insulin resistance) leading to diet-induced type 2 diabetes associated with hypertriglyceridemia, hypercholesterolemia, and hypertension. Dietary modulation affected growth rate (weight gain and central adiposity) to impact disease progression. This rodent model represents a novel system of gene-diet interactions affecting energy utilization that can provide insight into the prevention and treatment of the type 2 diabetes and Metabolic Syndrome.  相似文献   
38.
Aseries of obtusatic acid analogues has been synthesized and evaluated as inhibitors of leukotriene B(4) (LTB(4)) biosynthesis and as antiproliferative agents. The 4-O-benzylated and the 4-O-demethylated congeners were the most potent inhibitors of LTB(4) production of the depside class of compounds, with IC(50) values in the submicromolar range. Furthermore, these compounds do not function as redox-based inhibitors because they were not reactive against a stable free radical, 2,2-diphenyl-1-picrylhydrazyl, and did not produce appreciable amounts of deoxyribose degradation as a measure of their potency to generate hydroxyl radicals. Some obtusatic acid congeners were also potent inhibitors of keratinocyte growth. Growth inhibition was not mediated by damage to the cell membrane, as the activity of lactate dehydrogenase released from the cytoplasm was in the control range.  相似文献   
39.
To test the ability of Gianturco expandable metallic stents to dilate and maintain patency in stenotic venae cavae, stenosis of the inferior vena cava was created in seven mongrel dogs by the percutaneous injection of absolute ethanol into the paravascular retroperitoneal space. Gianturco stents, placed across the stenotic segment, resulted in successful dilatation with improved hemodynamics in four dogs. The stents failed to dilate an occluded vena cava in one dog; in the remaining dogs, stent placement was complicated by early migration and occlusion. Gianturco stents were placed in two patients, one with superior vena cava syndrome and one with retroperitoneal fibrosis that obstructed the inferior vena cava, and resulted in immediate relief of presenting symptoms. These results should be viewed cautiously, but further investigation into the clinical use of the stents is indicated, especially for patients for whom other treatments are difficult.  相似文献   
40.
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