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   111篇
  免费   3篇
耳鼻咽喉   2篇
基础医学   11篇
口腔科学   5篇
临床医学   14篇
内科学   20篇
皮肤病学   1篇
神经病学   18篇
外科学   9篇
预防医学   6篇
眼科学   9篇
药学   15篇
肿瘤学   4篇
  2024年   1篇
  2023年   2篇
  2022年   6篇
  2021年   3篇
  2020年   4篇
  2019年   6篇
  2018年   1篇
  2017年   4篇
  2016年   4篇
  2015年   1篇
  2014年   6篇
  2013年   2篇
  2012年   14篇
  2011年   17篇
  2010年   2篇
  2009年   5篇
  2008年   7篇
  2007年   6篇
  2006年   6篇
  2005年   5篇
  2004年   2篇
  2003年   6篇
  2002年   2篇
  2001年   1篇
  1997年   1篇
排序方式: 共有114条查询结果,搜索用时 15 毫秒
1.
2.
BACKGROUND:: Fibromyalgia is a chronic pain syndrome that affects about 2% of the U.S. general population, with greater prevalence among women (3.5%) than men (0.5%). Previous research results suggest that the experience of pain (allodynia) upon sphygmomanometry may indicate the presence of fibromyalgia. OBJECTIVE:: The aim of this study was to confirm these findings in patients with fibromyalgia and other chronic pain conditions and evaluate the use of sphygmomanometry as a potential screening tool for the identification of patients with fibromyalgia. METHODS:: A total of 150 people participated in this multicenter, cross-sectional observational study. The study included a physician-conducted evaluation to determine if the participant met the American College of Rheumatology (ACR) 1990 diagnostic criteria for fibromyalgia. The presence of sphygmomanometry-evoked allodynia was assessed during a seated cuff pressure inflation that was repeated three times on each arm. Each site was provided a sphygmomanometer to ensure standardization, and the pressure of the cuff at the moment of pain initiation was recorded. If the patient did not indicate pain prior to 180 mmHg, then the inflation was stopped, a notation of no pain was made, and a cuff pressure of 180 mmHg was recorded. The mean of the six cuff pressure measurements was used for the analyses. Logistic regression was performed to analyze the relationship between sphygmomanometry-evoked allodynia and fibromyalgia. RESULTS:: The evaluable sample was 148 (one participant had too large an arm circumference for the sphygmomanometer and another did not receive the clinician evaluation of ACR-determined fibromyalgia diagnosis). Over half of the participants were determined to have an ACR diagnosis of fibromyalgia. Of these, 71 (91%) were women and had an average age of 54 years. Of the 70 participants with no fibromyalgia diagnosis, 42 (60%) were women and also had an average age of 54 years. Sixty-one (78%) of the fibromyalgia participants, compared with 25 (36%) of those with no fibromyalgia diagnosis, reported sphygmomanometry-evoked allodynia. The participants with fibromyalgia reported pain ata lower cuff pressure compared with those without fibromyalgia (132 mmHg vs. 166 mmHg, p < .01). The logistic regression showed that sphygmomanometry-evoked allodynia predicted an ACR-determined FM diagnosis (χ = 19.4, p < .01). DISCUSSION:: These findings support previous research suggesting that patients who report pain upon sphygmomanometry may warrant further evaluation for the presence of fibromyalgia.  相似文献   
3.
The objectives of this study were to determine the direction and pattern of flow of irrigating solutions inside simulated root canals with different irrigation needles; and to determine whether different needle designs increase the likelihood of irrigating solution passing through the apical foramen. Two types of needles were compared: a standard needle with a bevel and an open end, and a needle with a side opening and closed rounded tip. Observations of irrigant flow within the canals indicated that the side‐venting needle can be dangerous if the needle gauge is small and it reaches the full length of the canal, since this allowed irrigants to flow into the periapical area. With the standard needle, the fluid did not go beyond the tip of the needle when minimal irrigating pressure was employed. As the size of canal increased, the fluid did not extrude beyond the tip of both needles. However, if the needles bound in the canals, then the fluid was forced away from the needle tip, and the pressure applied to the syringe was directly proportional to the distance the fluid flowed away from the needle tip. Both side‐venting and standard needles can be used for irrigation safely and effectively if a dynamic irrigation technique (moving the needle up and down inside the canals while irrigating) is employed.  相似文献   
4.
Dengue Fever (DF) may evolve into two life threatening forms—Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS). DHF is associated with increased vascular permeability and plasma leakage causing thrombocytopenia and loss of clotting factors into the third space and may result in bleeding initially due to thrombocytopenia and later due to disseminated intravascular coagulation (DIC), often as a terminal event. Prompt recognition and treatment of minor bleeds in DF children with incipient DIC with component therapy may be associated with improved survival while failure to do so is usually catastrophic. A sensitive marker for early DIC is the presence of D-dimer (DD) in the blood. To determine the correlation between the severity of thrombocytopenia and early DIC in children with DHF. The impact of additional factors like age and shock will also be evaluated. Case control prospective study of 60 DHF sero -positive children (1–15 years) with thrombocytopenia. After clinical evaluation they were divided into two equal groups based on the degree of thrombocytopenia (more than/less than 30,000/mm3). PT/APTT and DD levels were estimated in all children of both groups and statistical correlation was done. There was no significant difference in the DD levels between the two groups. However, children in either group, presenting with clinical features of shock and thrombocytopenia had significantly higher DD levels. Empirical component therapy in children with DHF based purely on their low platelet counts may not be justified. However, in DHF children with thrombocytopenia and features of shock, aggressive component therapy may prevent subsequent bleeding and may be justified.  相似文献   
5.
6.
Manganese (Mn) exposure causes manganism, a neurological disorder similar to Parkinson's disease. However, the cellular mechanism by which Mn induces dopaminergic neuronal cell death remains unclear. In the present study, we sought to investigate the key downstream apoptotic cell signaling events that contribute to Mn-induced cell death in mesencephalic dopaminergic neuronal (N27) cells. Mn exposure induced a dose-dependent increase in neuronal cell death in N27 cells. The cell death was accompanied by sequential activation of mitochondrial-dependent proapoptotic events, including cytochrome c release, caspase-3 activation, and DNA fragmentation, but not caspase-8 activation, indicating that the mitochondrial-dependent apoptotic cascade primarily triggers Mn-induced apoptosis. Notably, Mn treatment proteolytically activated protein kinase Cdelta (PKCdelta), a member of a novel class of protein kinase C. The caspase-3 specific inhibitor benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethylketone (Z-DEVD-FMK) significantly blocked PKCdelta cleavage and its kinase activity, indicating that caspase-3 mediates the proteolytic activation. Cotreatment with the PKCdelta inhibitor rottlerin or the caspase-3 inhibitor Z-DEVD-FMK almost completely blocked Mn-induced DNA fragmentation. Additionally, N27 cells expressing a catalytically inactive PKCdelta(K376R) protein (PKCdelta dominant negative mutant) or a caspase cleavage resistant PKCdelta(D327A) protein (PKCdelta cleavage resistant mutant) were found to be resistant to Mn-induced apoptosis. To further establish the proapoptotic role of PKCdelta, RNA interference-mediated gene knockdown was performed. Small interfering RNA suppression of PKCdelta expression protected N27 cells from Mn-induced apoptotic cell death. Collectively, these results suggest that caspase-3-dependent proteolytic activation of PKCdelta plays a key role in Mn-induced apoptotic cell death.  相似文献   
7.
Two hundred and eighteen bacterial isolates obtained from various clinical samples were subjected to Gram stain by conventional method. For all the isolates potassium hydroxide (KOH) string test and sensitivity to vancomycin were done. Gram positive bacteria showed 100% sensitivity to vancomycin as also 100% negativity for string test. Of the gram negative bacteria, 99.42% were resistant to vancomycin while 98.85% were positive for the string test. KOH and vancomycin tests are simple, inexpensive and can be used in addition to Gram staining for rapid identification of bacterial cultures.  相似文献   
8.
1-Methyl-4-phenylpyridinium (MPP+), the neurotoxic metabolite of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine), induces apoptosis in dopaminergic neurons; however, the cellular mechanisms underlying the degenerative process are not well understood. In the present study, we demonstrate that caspase-3 mediated proteolytic activation of protein kinase C delta (PKC delta) is critical in MPP+-induced oxidative stress and apoptosis. MPP+ exposure in rat dopaminergic neuronal cells resulted in time-dependent increases in reactive oxygen species generation, cytochrome c release, and caspase-9 and caspase-3 activation. Interestingly, MPP+ induced proteolytic cleavage of PKC delta (72-74 kDa) into a 41-kDa catalytic and a 38-kDa regulatory subunit, resulting in persistently increased kinase activity. The caspase-3 inhibitor Z-DEVD-fmk effectively blocked MPP+-induced PKC delta cleavage and kinase activity, suggesting that the proteolytic activation is caspase-3 mediated. Similar results were seen in MPP+-treated rat midbrain slices. Z-DEVD-fmk and the PKC delta specific inhibitor rottlerin almost completely blocked MPP+-induced DNA fragmentation. The superoxide dismutase mimetic, MnTBAP also effectively attenuated MPP+-induced caspase-3 activation, PKC delta cleavage, and DNA fragmentation. Furthermore, rottlerin attenuated MPP+-induced caspase-3 activity without affecting basal activity, suggesting positive feedback activation of caspase-3 by PKC delta. Intracellular delivery of catalytically active recombinant PKC delta significantly increased caspase-3 activity, further indicating that PKC delta regulates caspase-3 activity. Finally, over-expression of a kinase inactive PKC delta K376R mutant prevented MPP+-induced caspase activation and DNA fragmentation, confirming the pro-apoptotic function of PKC delta in dopaminergic cell death. Together, we demonstrate for the first time that MPP+-induced oxidative stress proteolytically activates PKC delta in a caspase-3-dependent manner to induce apoptosis and up-regulate the caspase cascade in dopaminergic neuronal cells.  相似文献   
9.
10.
Recent studies from our laboratory demonstrated that the protein kinase C (PKC) delta isoform is an oxidative stress-sensitive kinase and a key mediator of apoptotic cell death in Parkinson's Disease (PD) models (Eur J Neurosci 18:1387-1401, 2003; Mol Cell Neurosci 25:406-421, 2004). We showed that native PKC delta is proteolytically activated by caspase-3 and that suppression of PKC delta by dominant-negative mutant or small interfering RNA against the kinase can effectively block apoptotic cell death in cellular models of PD. In an attempt to translate the mechanistic studies to a neuroprotective strategy targeting PKC delta, we systematically characterized the neuroprotective effect of a PKC delta inhibitor, rottlerin, in 1-methyl-4-phenylpyridinium (MPP(+))-treated primary mesencephalic neuronal cultures as well as in an 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) animal model of PD. Rottlerin treatment in primary mesencephalic cultures significantly attenuated MPP(+)-induced tyrosine hydroxylase (TH)-positive neuronal cell and neurite loss. Administration of rottlerin, either intraperitoneally or orally, to C57 black mice showed significant protection against MPTP-induced locomotor deficits and striatal depletion of dopamine and its metabolite 3,4-dihydroxyphenylacetic acid. Notably, rottlerin post-treatment was effective even when MPTP-induced depletion of dopamine and its metabolites was greater than 60%, demonstrating its neurorescue potential. Furthermore, the dose of rottlerin used in neuroprotective studies effectively attenuated the MPTP-induced PKC delta kinase activity. Importantly, stereological analysis of nigral neurons revealed rottlerin treatment significantly protected against MPTP-induced TH-positive neuronal loss in the substantia nigra compacta. Collectively, our findings demonstrate the neuroprotective effect of rottlerin in both cell culture and preclinical animal models of PD, and they suggest that pharmacological modulation of PKC delta may offer a novel therapeutic strategy for treatment of PD.  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