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   1572篇
  免费   113篇
  国内免费   5篇
耳鼻咽喉   6篇
儿科学   79篇
妇产科学   32篇
基础医学   183篇
口腔科学   40篇
临床医学   119篇
内科学   417篇
皮肤病学   32篇
神经病学   106篇
特种医学   34篇
外科学   215篇
综合类   12篇
预防医学   141篇
眼科学   70篇
药学   103篇
中国医学   6篇
肿瘤学   95篇
  2023年   21篇
  2022年   21篇
  2021年   49篇
  2020年   34篇
  2019年   63篇
  2018年   51篇
  2017年   37篇
  2016年   36篇
  2015年   54篇
  2014年   66篇
  2013年   85篇
  2012年   88篇
  2011年   102篇
  2010年   64篇
  2009年   45篇
  2008年   84篇
  2007年   86篇
  2006年   88篇
  2005年   66篇
  2004年   61篇
  2003年   88篇
  2002年   73篇
  2001年   42篇
  2000年   37篇
  1999年   22篇
  1998年   7篇
  1997年   12篇
  1996年   7篇
  1995年   7篇
  1994年   6篇
  1992年   13篇
  1991年   11篇
  1990年   16篇
  1989年   19篇
  1988年   15篇
  1987年   14篇
  1986年   11篇
  1985年   11篇
  1984年   8篇
  1983年   10篇
  1980年   4篇
  1979年   4篇
  1978年   6篇
  1977年   4篇
  1975年   6篇
  1973年   3篇
  1971年   4篇
  1970年   4篇
  1969年   3篇
  1965年   3篇
排序方式: 共有1690条查询结果,搜索用时 15 毫秒
71.

Objective

We assessed knowledge and practices regarding immunization guidelines and the Florida Certificate of Immunization (DH-680) based on FL-DOH and CDC recommendations, to identify the cause of the increasing number of erroneously issued temporary medical exemptions (TME) among selected health care providers in Miami-Dade County Florida.

Methodology

After reviewing immunization certificates from all public schools, a list of physicians who improperly issued 3 or more TMEs, defined as one given to a child who was up to date for their kindergarten and seventh grade requirements, was compiled. The DOH-Miami-Dade developed educational materials and questionnaires, and conducted face-to-face interviews and interventions during site visits to these providers (n = 134). Data was analyzed using SAS 9.2.

Results

Of the 104 questionnaires completed, 4 (3.85%) had correct answers to all 10 vaccine knowledge and practice related questions, while 10 (9.62%) had 7 or more incorrect answers. Frequently missed questions included: the required doses of varicella vaccine for seventh grade students entering the 2011–12 school year (86, 82.7%) and the proper scenario for issuing a TME (57, 54.8%).

Conclusions

In order to eliminate the improper use of TMEs, long-term efforts are needed to provide immunization-related educational materials and trainings to the medical community regarding vaccinations. These findings also suggest a need for enhanced explanation in multiple languages on the current Florida Immunization Certificate. Due to enhanced surveillance and education, the number of TMEs for kindergarten and seventh grade students was reduced by 12% and 4.9%, respectively, during the 2011 and 2012 school year.  相似文献   
72.
Mosaic genetic mutations may be somatic, germline, or “gonosomal” and have the potential to cause genetic syndromes, disorders, or malformations. Mutations can occur at any point in embryonic development and the timing determines the extent of distribution of the mutation throughout the body and different tissue types. The eye and visual pathway offer a unique opportunity to study somatic and gonosomal mosaic mutations as the eye consists of tissues derived from all three germ layers allowing disease pathology to be assessed with noninvasive imaging. In this review, we describe systemic and ocular manifestations in a child with mosaic Coffin‐Siris syndrome. The patient presented with a significant medical history of accommodative esotropia and hyperopia, macrocephaly, polydactyly, global developmental delay, hypotonia, ureteropelvic junction (UPJ) obstruction, and brain MRI abnormalities. The ophthalmic findings in this patient were nonspecific, however, they are consistent with ocular manifestations reported in other patients with Coffin‐Siris syndrome. We also review ophthalmic findings of select mosaic chromosomal and single‐gene disorders. Ophthalmic assessment alongside clinical genetic testing may play an important role in diagnosis of genetic syndromes as well as understanding disease pathology, particularly when mosaicism plays a role.  相似文献   
73.
74.
75.
Brief: Real-world data in naïve HIV-1 patients demonstrate that dolutegravir plus lamivudine in a multiple tablet regimen is effective, safe, and satisfactory; it causes moderately increasing weight and abdominal circumference and is administrable on a test-and-treat strategy. Background: Our objectives were to determine the real-life effectiveness and safety of DT with dolutegravir (50 mg/QD) plus lamivudine (300 mg/QD) in a multiple-tablet regimen (MTR) in naïve PLHIV followed up for 48 weeks and to evaluate the compliance and satisfaction of patients. Material and methods: An open, single-arm, multicenter, non-randomized clinical trial from May 2019 through September 2020 with a 48-week follow-up. Results: The study included 88 PLHIV patients (87.5% male) with a mean age of 35.9 years; 76.1% were MSM patients. The mean baseline CD4 was 516.4 cells/uL, with a viral load (VL) of 4.49 log10, and 11.4% were in the AIDS stage. DT started within 7 days of first specialist consultation in all patients and the same day in 84.1%; 3.4% had baseline resistance mutations (K103N, V106I + E138A, and V108I); 12.5% were lost to follow-up. At week 48, 86.3% had VL < 50 cop/uL by intention-to-treat analysis and 98.7% by per-protocol (PP) analysis. Virological failure (VF) was recorded in 1.1%, with no resistance mutation. One blip was detected in 5.2% without VF. Three reported anxiety, dizziness, and cephalgia, respectively, at week 4 and one reported insomnia at week 24; none reported adverse events at week 48. The mean weight was 4 kg higher at 48 weeks (p = 0.0001) and abdominal circumference 3 cm larger at 24 weeks (p = 0.022). No forgetfulness occurred in 98.7% of patients. Patient satisfaction was 90/100 at 4, 24, and 48 weeks. Conclusion: Real-world data demonstrate that dolutegravir plus lamivudine in MTR is effective, safe, and satisfactory, moderately increasing weight and abdominal circumference and administrable on a test-and-treat strategy.  相似文献   
76.
Alveolar hypoxia is the most powerful pulmonary vasoconstrictor. In a previous work, we did not demonstrate significant changes in vascular reactivity and edema formation in an isolated canine lobe model during alveolar hypoxia. The purpose of this study is to define vascular pulmonary reactivity and edema formation after induction of pulmonary vasoconstriction using a prostaglandin inhibitor like tiaprofenic acid and alveolar hypoxia. Six isolated canine pulmonary lobules were instrumented and studied, all of them under two conditions (normoxia FIO2 21% and hypoxia FIO2 5%) four starting in normoxia condition and 2 starting in hypoxia condition. RESULTS: No significant changes in filtration rate were found, normoxia 0.42 +/- 0.41, hypoxia 0.37 +/- 0.51 ml/min/100 g pulmonary tissue P = NS. The arterial pressure in basal conditions was 25.1 +/- 6.21, and during hypoxia increased to 37 +/- 7.19 cm H2O (Delta 12.0 +/- 1.2 cm H2O). P < 0.001. CONCLUSION: Hypoxia vascular reactivity was significantly increased in tiaprofenic acid pretreated isolated canine lobes, no changes in pulmonary permeability was found nor increased rate in edema formation.  相似文献   
77.
BackgroundSeveral studies have shown a correlation between an altered metabolome and respiratory allergies. The epithelial barrier hypothesis proposes that an epithelial barrier dysfunction can result in allergic diseases development. Der p 1 allergen from house dust mite is a renowned epithelial barrier disruptor and allergy initiator due to its cysteine‐protease activity. Here, we compared the metabolic profile of the bronchial epithelium exposed or not to Der p 1 during barrier establishment to understand its active role in allergy development.MethodsCalu‐3 cells were cultivated in air‐liquid interface cultures and exposed to either Der p 1 or Ole e 1 allergens during barrier establishment. The comparative metabolomics analysis of apical and basolateral media were performed using liquid chromatography and capillary electrophoresis both coupled to mass spectrometry.ResultsWe showed that epithelial barrier disruption by Der p 1 was associated with a specific metabolic profile, which was highly dependent on the state of the epithelium at the time of contact. Moreover, an apical‐basolateral distribution of the metabolites was also observed, indicating a compartmentalization of the response with differential metabolic patterns. A number of metabolites were changed by Der p 1, mainly related to amino acids metabolism, such as L‐arginine, L‐kynurenine and L‐methionine.ConclusionThis work is the first report on the metabolic response in human bronchial epithelial cells associated with cysteine‐protease Der p 1 activity, which could contribute to allergy development. Moreover, it supports a reformulated epithelial barrier hypothesis that might help to explain allergies and their increasing prevalence.  相似文献   
78.
Pyometra is a pus accumulation in the endometrium cavity, with an incidence from 0.02% to 1.5%. The benign senile pyometra is a disease mainly reported in elder women, with an average age of 74 years. We present the case of a 59-year-old woman with the diagnosis of benign senile pyometra. The patient came to our service presenting purulent vaginal discharge, in bad condition with pelvic pain and altered hematic cytology. In the physical examination a pelvic mass was found, in the vaginal examination, the cervix was found estenotic, and the hysterometer could not be introduced. The image studies revealed an increased size of the uterus was liquid collection in its interior, compatible with blood or pus. We performed exploratory laparotomy, founding two abscecess in the uterin fundus which suffered rupture during the procedure. Abdominal hysterectomy with bilateral salpigooforectomy was performed, there were not other complications. Post surgical period was managed with antibiotics and close surveillance. The patient was discharged four days later with good response to the treatment. In the anatomophatological study no evidence of cervical or endometrial neoplasia was found.  相似文献   
79.
OBJECTIVE: The optimal prophylactic strategy and treatment regimen for deep venous thrombosis (DVT) in hospitalized pediatric patients is not clearly established. This study assessed the incidence, risk factors, and treatment patterns for DVT among pediatric patients admitted to a hospital ward. METHODS: Children (aged <17 years) admitted to a single tertiary-care hospital during a 14-year period who developed or presented with DVT were retrospectively identified. Patient demographic and clinical data were analyzed retrospectively. Patients who developed DVT in the hospital were stratified according to the Wells clinical probability scoring system from criteria noted before the diagnosis. Treatment patterns and outcomes were evaluated between the two time intervals of 1992 to 2001 (group I) and 2002 to 2005 (group II). RESULTS: Between 1992 and 2005, 358 children were evaluated for DVT, and 99 (52 boys, 47 girls) were admitted to the hospital and were determined to have DVT by confirmatory imaging. A prior DVT (12 total) was present in eight of the 21 patients admitted for DVT treatment; of the remaining, only seven received DVT prophylaxis on admission. In those developing a DVT, the inpatient clinical probability score was 21% (low), 40% (moderate), and 39% (high). The most common risk factor in those with prehospital DVT was a prior DVT (38%) or thrombophilic condition (33%), whereas inpatients had a central catheter (45%), with nearly 50% in the femoral vein. Children acquiring an inpatient DVT had concomitant severe respiratory (17%), oncologic (14%), and/or infectious (15%) diseases and required a prolonged intensive care unit (12.7 days) stay. Prehospital DVT was lower extremity predominant (90%) and statistically different from inpatient-acquired DVT (62%, P = .01). Treatment patterns between periods I and II revealed a trend to more low-molecular-weight heparin and less unfractionated heparin use (P = .09). Three patients died (one fatal pulmonary embolism). The number of recognized cases per 10,000 admissions increased from 0.3 to 28.8 from 1992 to 2005. CONCLUSION: The incidence of DVT in hospitalized children is increasing. Those presenting with DVT typically have prior DVT, thrombophilia, or lower extremity disease. Our study suggests that children admitted with severe medical conditions who require a prolonged intensive care unit stay in addition to central venous access (especially via the femoral vein) should be considered candidates for DVT prophylaxis. A clinical probability scoring system alone cannot stratify patients sufficiently to forgo prophylaxis in hopes of a rapid clinical diagnosis. Childhood-specific level 1 trials aimed at determining guidelines for DVT prophylaxis are urgently required.  相似文献   
80.
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