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   190篇
  免费   14篇
  国内免费   1篇
耳鼻咽喉   5篇
儿科学   3篇
妇产科学   6篇
基础医学   34篇
口腔科学   1篇
临床医学   17篇
内科学   52篇
皮肤病学   3篇
神经病学   18篇
特种医学   2篇
外科学   17篇
一般理论   1篇
预防医学   13篇
眼科学   1篇
药学   18篇
肿瘤学   14篇
  2024年   1篇
  2023年   4篇
  2022年   3篇
  2021年   22篇
  2020年   8篇
  2019年   11篇
  2018年   8篇
  2017年   8篇
  2016年   10篇
  2015年   13篇
  2014年   10篇
  2013年   14篇
  2012年   14篇
  2011年   24篇
  2009年   7篇
  2008年   10篇
  2007年   8篇
  2006年   6篇
  2005年   9篇
  2004年   5篇
  2003年   4篇
  2002年   2篇
  2001年   1篇
  1999年   1篇
  1996年   1篇
  1975年   1篇
排序方式: 共有205条查询结果,搜索用时 15 毫秒
1.
2.
Maternal and Child Health Journal - The purpose of this study was to explore the postpartum experiences of publicly-insured women of color, and identify how postpartum care can be improved to...  相似文献   
3.

Background:

The increasingly recognized role of inflammation in the pathogenesis and prognosis of depression has led to a renewed focus on the immunomodulatory properties of compounds with antidepressant action. Studies have, so far, explored such properties in human blood samples and in animal models.

Methods:

Here we used the more relevant model of human hippocampal progenitor cells exposed to an inflammatory milieu, induced by treatment with IL-1β. This increased the levels of a series of cytokines and chemokines produced by the cells, including a dose- and time-dependent increase of IL-6. We investigated the immunomodulatory properties of four monoaminergic antidepressants (venlafaxine, sertraline, moclobemide, and agomelatine) and two omega-3 polyunsaturated fatty acids (n-3 PUFAs; eicosapentanoic acid [EPA] and docosahexanoic acid [DHA]).

Results:

We found that venlafaxine and EPA were anti-inflammatory: venlafaxine decreased IL-6, with a trend for decreases of IL-8 and IP-10, while EPA decreased the levels of IL-6, IL-15, IL-1RA, and IP-10. These effects were associated with a corresponding decrease in NF-kB activity. Unexpectedly, sertraline and DHA had pro-inflammatory effects, with sertraline increasing IFN-α and IL-6 and DHA increasing IL-15, IL-1RA, IFN-α, and IL-6, though these changes were also associated with a decrease in NF-kB activity, suggesting distinct modes of action. Agomelatine and moclobemide had no effect on IL-6 secretion.

Conclusions:

These observations indicate that monoaminergic antidepressants and n-3 PUFAs have distinctive effects on immune processes in human neural cells. Further characterization of these actions may enable more effective personalization of treatment based on the inflammatory status of patients.  相似文献   
4.
The spatial accuracy of transcranial magnetic stimulation (TMS) may be as small as a few millimeters. Despite such great potential, navigated TMS (nTMS) mapping is still underused for the assessment of motor plasticity, particularly in clinical settings. Here, we investigate the within‐limb somatotopy gradient as well as absolute and relative reliability of three hand muscle cortical representations (MCRs) using a comprehensive grid‐based sulcus‐informed nTMS motor mapping. We enrolled 22 young healthy male volunteers. Two nTMS mapping sessions were separated by 5–10 days. Motor evoked potentials were obtained from abductor pollicis brevis (APB), abductor digiti minimi, and extensor digitorum communis. In addition to individual MRI‐based analysis, we studied normalized MNI MCRs. For the reliability assessment, we calculated intraclass correlation and the smallest detectable change. Our results revealed a somatotopy gradient reflected by APB MCR having the most lateral location. Reliability analysis showed that the commonly used metrics of MCRs, such as areas, volumes, centers of gravity (COGs), and hotspots had a high relative and low absolute reliability for all three muscles. For within‐limb TMS somatotopy, the most common metrics such as the shifts between MCR COGs and hotspots had poor relative reliability. However, overlaps between different muscle MCRs were highly reliable. We, thus, provide novel evidence that inter‐muscle MCR interaction can be reliably traced using MCR overlaps while shifts between the COGs and hotspots of different MCRs are not suitable for this purpose. Our results have implications for the interpretation of nTMS motor mapping results in healthy subjects and patients with neurological conditions.  相似文献   
5.

Background

Aim of the study was to find out which myocardial repolarization parameters predict reperfusion ventricular tachycardia and fibrillation (VT/VF) and determine how these parameters express in ECG.

Methods

Coronary occlusion and reperfusion (30/30 min) was induced in 24 cats. Local activation and end of repolarization times (RT) were measured in 88 intramyocardial leads. Computer simulations of precordial electrograms were performed.

Results

Reperfusion VT/VF developed in 10 animals. Arrhythmia-susceptible animals had longer RTs in perfused areas [183(177;202) vs 154(140;170) ms in susceptible and resistant animals, respectively, P < 0.05]. In logistic regression analysis, VT/VFs were associated with prolonged RTs in the perfused area (OR 1.068; 95% CI 1.012–1.128; P = 0.017). Simulations demonstrated that prolonged repolarization in the perfused/border zone caused precordial terminal T-wave inversion.

Conclusions

The reperfusion VT/VFs were independently predicted by the longer RT in the perfused zone, which was reflected in the terminal negative phase of the electrocardiographic T-wave.  相似文献   
6.
In order to design a sensor material for total antioxidant capacity determination we have prepared silica and silica–titania xerogels doped with iron(III) and modified with 1,10-phenanthroline. Titanium(IV) tetraethoxyde content in the precursors (titanium(IV) tetraethoxyde and tetraethyl orthosilicate) mixtures has been varied from 0 to 12.5% vol. Iron(III) concentrations in sol has been varied from 1 to 100 mM. The increase of titanium(IV) content has led to a decrease in BET surface area and average pore diameter and an increase of micropore surface area and volume, which has resulted in better iron(III) retention in the xerogels. Iron(III), immobilized in the xerogel matrix, retains its ability to form complexes with 1,10-phenanthroline and to be reduced to iron(II). Static capacities for 1,10-phenanthroline have been determined for all the iron(III) doped xerogels (0.207 mmol/g–0.239 mmol/g) and they are not dependent on the iron(III) content. Sensor materials—xerogels doped with iron(III) and modified with 1,10-phenanthroline—have been used for antioxidants (catechol, gallic and ascorbic acids, and sulphite) solid phase spectrophotometric determination. Limits of detection for catechol, gallic and ascorbic acids, and sulphite equal 7.8 × 10−6 M, 5.4 × 10−6 M, 1.2 × 10−5 M, and 3.1 × 10−4 M, respectively. The increase of titanium(IV) content in sensor material has led to an increase of the reaction rate and the sensitivity of determination. Proposed sensor materials have been applied for total antioxidant capacity (in gallic acid equivalents) determination in soft beverages, have demonstrated high stability, and can be stored up to 6 months at room temperature.  相似文献   
7.
8.
We have devised a simple method to purify mitotically active Schwann cells (SC) from peripheral nerves of adult mice. Nerves were predegenerated in vitro for 7 days and after dissociation cells were plated on poly-L-lysine/laminin coated dishes in N2 serum-free culture medium supplemented with forskolin and heregulin-beta1. Primary cultures were purified from contaminating fibroblasts by magnetic cell sorting (MACS) based on SC membrane specific expression of p75(NGFR) and enriched to about 99% of SC after MACS from 34 to 91% before sorting. After sorting, purified adult mouse SC were propagated for three passages until confluent to a total surface of 160 cm(2) per mouse (two sciatic and two trigeminal nerves). In addition, we show that this method can be used to purify tumoral SC from mouse NF2-related schwannomas.  相似文献   
9.
Retiform perineurioma is a rare distinct histologic subtype of benign soft tissue perineurioma. We report 1 case of retiform perineurioma with a superficial invasion of the adjacent skeletal muscle. The patient was a 34-year-old woman with a neoplasm located between the deltoid muscle and the biceps. Histologically, the tumor was nonencapsulated, composed exclusively of perineurial cells without cytologic and tissue atypia. There were focal areas in which the neoplastic cells infiltrated the muscle tissue, widely separating the bundles. This case may represent a diagnostic pitfall as it can be confused with a malignant perineurioma.  相似文献   
10.
Background: A tradition of separation of the mother and baby after birth still persists in many parts of the world, including some parts of Russia, and often is combined with swaddling of the baby. The aim of this study was to evaluate and compare possible long‐term effects on mother‐infant interaction of practices used in the delivery and maternity wards, including practices relating to mother‐infant closeness versus separation. Methods: A total of 176 mother‐infant pairs were randomized into four experimental groups: Group I infants were placed skin‐to‐skin with their mothers after birth, and had rooming‐in while in the maternity ward. Group II infants were dressed and placed in their mothers’ arms after birth, and roomed‐in with their mothers in the maternity ward. Group III infants were kept in the nursery both after birth and while their mothers were in the maternity ward. Group IV infants were kept in the nursery after birth, but roomed‐in with their mothers in the maternity ward. Equal numbers of infants were either swaddled or dressed in baby clothes. Episodes of early suckling in the delivery ward were noted. The mother‐infant interaction was videotaped according to the Parent‐Child Early Relational Assessment (PCERA) 1 year after birth. Results: The practice of skin‐to‐skin contact, early suckling, or both during the first 2 hours after birth when compared with separation between the mothers and their infants positively affected the PCERA variables maternal sensitivity, infant's self‐regulation, and dyadic mutuality and reciprocity at 1 year after birth. The negative effect of a 2‐hour separation after birth was not compensated for by the practice of rooming‐in. These findings support the presence of a period after birth (the early “sensitive period”) during which close contact between mother and infant may induce long‐term positive effect on mother‐infant interaction. In addition, swaddling of the infant was found to decrease the mother’s responsiveness to the infant, her ability for positive affective involvement with the infant, and the mutuality and reciprocity in the dyad. Conclusions: Skin‐to‐skin contact, for 25 to 120 minutes after birth, early suckling, or both positively influenced mother‐infant interaction 1 year later when compared with routines involving separation of mother and infant.  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