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   2694篇
  免费   208篇
  国内免费   16篇
耳鼻咽喉   31篇
儿科学   43篇
妇产科学   51篇
基础医学   410篇
口腔科学   26篇
临床医学   306篇
内科学   682篇
皮肤病学   76篇
神经病学   296篇
特种医学   34篇
外科学   216篇
综合类   5篇
一般理论   1篇
预防医学   279篇
眼科学   50篇
药学   215篇
中国医学   9篇
肿瘤学   188篇
  2024年   5篇
  2023年   29篇
  2022年   92篇
  2021年   119篇
  2020年   81篇
  2019年   112篇
  2018年   94篇
  2017年   86篇
  2016年   77篇
  2015年   82篇
  2014年   137篇
  2013年   141篇
  2012年   197篇
  2011年   220篇
  2010年   99篇
  2009年   118篇
  2008年   137篇
  2007年   161篇
  2006年   136篇
  2005年   132篇
  2004年   125篇
  2003年   137篇
  2002年   123篇
  2001年   17篇
  2000年   24篇
  1999年   19篇
  1998年   29篇
  1997年   22篇
  1996年   11篇
  1995年   17篇
  1994年   7篇
  1993年   8篇
  1992年   6篇
  1991年   14篇
  1990年   13篇
  1989年   7篇
  1988年   8篇
  1987年   13篇
  1986年   6篇
  1985年   4篇
  1984年   3篇
  1982年   10篇
  1981年   6篇
  1980年   7篇
  1979年   5篇
  1977年   2篇
  1975年   2篇
  1974年   6篇
  1970年   3篇
  1966年   3篇
排序方式: 共有2918条查询结果,搜索用时 125 毫秒
41.
IntroductionThe aim of this study was to assess several air-pressure settings for MI–E to determine their effect on peak cough flow (PCF), and to compare the best pressures with those are more common used in the literature (±40 cmH2O) in patients with neuromuscular disorders (NMD).MethodsAdults with NMD in whom MI–E was indicated were recruited. Assisted PCF was measured by an external pneumotachograph. The protocol included 9 PCF measures per patient: 1 baseline (non-assisted), 4 with increasing inspiratory pressures without negative pressure (10, 20, 30 and 40 cmH2O or maximum tolerated), and then 4 adding expiratory pressures (?10, ?20, ?30 and ?40 cmH2O or maximum tolerated) with maximum inspiratory pressure previously achieved.ResultsTwenty one patients were included, 61% with amyotrophic lateral sclerosis (ALS). Mean PCFs with recommended pressures (±40 cmH2O) were lower than the scored in the individualized steps of the titration protocol (197.7 ± 67 l/min vs 214.2 ± 60 l/min, p < 0.05). Regarding subgroups, mean PCFmax values in ALS patients with bulbar symptoms were significantly higher than those achieved with recommended pressures (163.6 ± 80 vs 189 ± 66 l/min, p < 0.05).ConclusionThe PCFmax obtained with the protocol did not always match the recommended settings. It may be advisable to perform MI–E titration assessed by non-invasive PCF monitoring in patients with NMD, especially in ALS with bulbar involvement to improve the therapy detecting airway collapse induced by high pressures.  相似文献   
42.

Objectives

Although hospital clinicians strive to effectively refer patients who require post-acute care (PAC), their discharge planning processes often vary greatly, and typically are not evidence-based.

Design

Quasi-experimental study employing pre-/postdesign. Aimed at improving patient-centered discharge processes, we examined the effects of the Discharge Referral Expert System for Care Transitions (DIRECT) algorithm that provides clinical decision support (CDS) regarding which patients to refer to PAC and to what level of care (home care or facility).

Setting and participants

Conducted in 2 hospitals, DIRECT data elements were collected in the pre-period (control) but discharging clinicians were blinded to the advice and provided usual discharge care. During the postperiod (intervention), referral advice was provided within 24 hours of admission to clinicians, and updated twice daily. Propensity modeling was used to account for differences between the pre-/post patient cohorts.

Measures

Outcomes compared between the control and the intervention periods included PAC referral rates, patient characteristics, and same-, 7-, 14-, and 30-day readmissions or emergency department visits.

Results

Although 24%–25% more patients were recommended for PAC referral by DIRECT algorithm advice, the proportion of patients receiving referrals for PAC did not significantly differ between the control (3302) and intervention (5006) periods. However, the characteristics of patients referred for PAC services differed significantly and inpatient readmission rates decreased significantly across all time intervals when clinicians had DIRECT CDS compared with without. There were no differences observed in return emergency department visits. Largest effects were observed when clinicians agreed with the algorithm to refer (yes/yes).

Conclusions/Implications

Our findings suggest the value of timely, automated, discharge CDS for clinicians to optimize PAC referral for those most likely to benefit. Although overall referral rates did not change with CDS, the algorithm may have identified those patients most in need, resulting in significantly lower inpatient readmission rates.  相似文献   
43.
Reduction mammoplasty is one of the most commonly performed procedures in plastic surgery. Occasionally, there are findings reported by pathologists that are unfamiliar to the treating surgeon. The aim of the present study was to determine the types of pathologies encountered in reduction mammoplasty specimens. From this list of diagnoses, a best practice guideline for management will be organized to better assist plastic surgeons in the management of patients with incidental findings on pathology reports. A total of 441 pathology reports from patients who underwent bilateral or unilateral reduction mammoplasty in the past three years were identified. A list of 21 different pathologies was generated from the pathology reports, along with supplemental data from recent texts and articles. Occult carcinomas were encountered in two cases (0.45%) and high-risk lesions were found in three cases (0.68%) at the authors’ institution. An algorithm was then constructed to organize the pathologies according to risk of malignancy and assign them to a management guideline. There are many different lesions encountered incidentally in reduction mammoplasty specimens that may or may not confer some cancer risk. It is important for plastic surgeons to know which lesions need closer follow-up to provide the best care for their patients.  相似文献   
44.
The fast-moving coronavirus disease 2019 (COVID-19) called for a rapid response to slowing down the viral spread and reduce the fatality associated to the pandemic. Policymakers have implemented a wide range of non-pharmaceutical interventions to mitigate the spread of the pandemic and reduce burdens on healthcare systems. An efficient response of healthcare systems is crucial to handle a health crisis. Understanding how non-pharmaceutical interventions have contributed to slowing down contagions and how healthcare systems have impacted on fatality associated with health crisis is of utmost importance to learn from the COVID-19 pandemic. We investigated these dynamics in Italy at the regional level. We found that the simultaneous introduction of a variety of measures to increase social distance is associated with an important decrease in the number of new infected patients detected daily. Contagion reduces by 1% with the introduction of lockdowns in an increasing number of regions. We also found that a robust healthcare system is crucial for containing fatality associated with COVID-19. Also, proper diagnosis strategies are determinant to mitigate the severity of the health outcomes. The preparedness is the only way to successfully adopt efficient measures in response of unexpected emerging pandemics.  相似文献   
45.
Nelson’s syndrome (NS) is characterized by the appearance and/or progression of ACTH-secreting pituitary macroadenomas in patients who had previously undergone bilateral adrenalectomy for the treatment of Cushing’s disease. Such corticotroph macroadenomas respond poorly to currently available therapeutic options which include surgery, radiotherapy and chemotherapy. P53 protein accumulation may be detected by immunohistochemistry in pituitary corticotroph adenomas and it has been suggested that it might be causally related to tumor development. Wild type P53 protein plays an important role in the cellular response to ionizing radiation and other DNA damaging agents and is mutated in many human tumors. In this study we report an adult male patient with NS who underwent both transsphenoidal and transcranial pituitary surgeries, conventional and stereotaxic radiotherapy and brachytherapy. Despite of the efforts to control tumor mass and growth, this macroadenoma displayed relentless growth and aggressive behavior. DNA extracted from the first two surgical samples, as well as DNA from peripheral blood leukocytes disclosed normal p53 sequence. DNA extracted from tumor samples obtained at surgeries performed after pituitary irradiation carried a somatic heterozygous mutation, consisting of a deletion of four cytosines between nucleotides 12,144–12,149 in exon 4 of the p53 gene. This frameshift mutation creates a stop codon in exon 4 excluding the expression of a functional protein from the defective allele. These data demonstrate a possible association between the P53 protein loss of function induced by radiotherapy and the aggressive course of the disease in this patient.  相似文献   
46.
Age related male hypogonadism, or “andropause”, is increasingly recognized as of frequent occurrence in older patients. Diagnosis requires both the presence of clinical symptoms and low testosterone levels. However, diagnosing andropause in this age group may be challenging since symptoms are frequently non specific and testosterone levels are influenced by a multitude of parameters such as lifestyle factors and chronic diseases. In this article we discuss the pathophysiology, definition and diagnostic difficulties of andropause in geriatric patients. Moreover, we review the relation between testosterone levels and frequent geriatric syndromes such as falls, osteoporosis, cognitive and mood disorders, anemia and cardiovascular disease. Finally, we examine the potential benefits and risks of testosterone replacement therapy in this age group.  相似文献   
47.
48.
49.
50.
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