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371.
The Canadian Society for Exercise Physiology, in partnership with the Public Health Agency of Canada, has initiated a review of their physical activity guidelines to promote healthy active living for Canadian children, youth, adults and older adults; previous guidelines were released in 2002, 2002, 1998 and 1999 respectively. Several background papers from this project were published recently and provide foundation evidence upon which to base new guidelines. Furthermore, comprehensive systematic reviews were completed to ensure a rigorous evaluation of evidence informing the revision of physical activity guidelines for asymptomatic populations. The overall guideline development process is being guided and assessed by the AGREE II instrument. A meeting of experts was convened to present the evidence complied to inform the guideline revisions. An independent expert panel was assembled to review the background materials and systematic reviews; listen to the presentations and discussions at the expert meeting; ask for clarification; and produce the present paper representing their interpretation of the evidence including grading of the evidence and their identification of needs for future research. The paper includes also their recommendations for evidence-informed physical activity guidelines.  相似文献   
372.
International Journal of Paediatric Dentistry 2010; 20: 193–200 Background. Interceptive extractions of deciduous canines are, from a patient perspective, poorly investigated. Aims. To describe pain, discomfort, and dental fear in connection to extractions of the deciduous canines, indicated as an orthodontic treatment procedure. Design. Thirty‐two Swedish children aged 7–9 years had all four deciduous canines extracted over three occasions. The children rated procedural and postoperative pain on visual analogue scales. Acceptance of injections and extractions was assessed by the treating dentists. Analgesic consumption and recovery time for drinking and eating was reported by parents. Dental fear was assessed using the Children’s Fear Survey Schedule questionnaire. Results. Procedural pain showed low median levels, although some individuals reported high values. Boys reported significantly more pain at appointments when two (as opposed to one) canines were extracted. Postoperative pain levels were low and use of analgesics sparse. Dental fear paralleled norm values and did not increase from pre‐ to post‐extraction. Conclusions. Pain management routines during extractions of this kind should be revised. Single tooth extractions seem to be preferable to extractions of two canines at the same appointment. Extraction of four deciduous canines should not cause major postoperative inconvenience; these extractions neither triggered nor increased dental fear.  相似文献   
373.
AIM:To isolate,characterize and investigate the antifungal activity of the root bark of Psorospermum corymbiferum(Clusiaceae).METHODS:The finely ground root bark of Psorospermum corymbiferum was cold-extracted by percolation with 98% ethanol(5.0 L) for two weeks.The ethanol extract was macerated with n-hexane,chloroform,ethylacetate and methanol successively to give the respective solvent extracts.Fractionation of the extract was done using column chromatography on silica gel with cyclohexene:ethylacetate(1...  相似文献   
374.

Background and purpose:

Ca2+-activated Cl currents (ICl(Ca)) in arterial smooth muscle cells are inhibited by phosphorylation. The Ca2+-activated Cl channel (ClCa) blocker niflumic acid (NFA) produces a paradoxical dual effect on ICl(Ca), causing stimulation or inhibition at potentials below or above 0 mV respectively. We tested whether the effects of NFA on ICl(Ca) were modulated by phosphorylation.

Experimental approach:

ICl(Ca) was elicited with 500 nM free internal Ca2+ in rabbit pulmonary artery myocytes. The state of global phosphorylation was altered by cell dialysis with either 5 mM ATP or 0 mM ATP with or without an inhibitor of calmodulin-dependent protein kinase type II, KN-93 (10 µM).

Key results:

Dephosphorylation enhanced the ability of 100 µM NFA to inhibit ICl(Ca). This effect was attributed to a large negative shift in the voltage-dependence of block, which was converted to stimulation at potentials <−50 mV, ∼70 mV more negative than cells dialysed with 5 mM ATP. NFA dose-dependently blocked ICl(Ca) in the range of 0.1–250 µM in cells dialysed with 0 mM ATP and KN-93, which contrasted with the stimulation induced by 0.1 µM, which converted to block at concentrations >1 µM when cells were dialysed with 5 mM ATP.

Conclusions and implications:

Our data indicate that the presumed state of phosphorylation of the pore-forming or regulatory subunit of ClCa channels influenced the interaction of NFA in a manner that obstructs interaction of the drug with an inhibitory binding site.  相似文献   
375.
376.
The role of HER4 in breast cancer is controversial and its role in relation to trastuzumab resistance remains unclear. We showed that trastuzumab treatment and its acquired resistance induced HER4 upregulation, cleavage and nuclear translocation. However, knockdown of HER4 by specific siRNAs increased trastuzumab sensitivity and reversed its resistance in HER2 positive breast cancer cells. Preventing HER4 cleavage by a γ-secretase inhibitor and inhibiting HER4 tyrosine kinase activity by neratinib decreased trastuzumab-induced HER4 nuclear translocation and enhanced trastuzumab response. There was also increased nuclear HER4 staining in the tumours from BT474 xenograft mice and human patients treated with trastuzumab. Furthermore, nuclear HER4 predicted poor clinical response to trastuzumab monotherapy in patients undergoing a window study and was shown to be an independent poor prognostic factor in HER2 positive breast cancer. Our data suggest that HER4 plays a key role in relation to trastuzumab resistance in HER2 positive breast cancer. Therefore, our study provides novel findings that HER4 activation, cleavage and nuclear translocation influence trastuzumab sensitivity and resistance in HER2 positive breast cancer. Nuclear HER4 could be a potential prognostic and predictive biomarker and understanding the role of HER4 may provide strategies to overcome trastuzumab resistance in HER2 positive breast cancer.  相似文献   
377.
目的:探讨潜伏梅毒患者与临床相关因素的关系。方法:收集并整理573例梅毒患者中361例潜伏梅毒患者临床资料,对潜伏梅毒患者的年龄、性别、病期、就诊原因、血清学检验及诊治情况的特征进行统计学分析。结果:潜伏梅毒占梅毒发病率的63%,21~50岁性活跃期的人群发病率较高,老年人病程较长,均为各种筛查确诊而发现;潜伏梅毒RPR滴度较低,滴度在1∶8以下占96.12%,潜伏梅毒治疗血清阴转率偏低,多出现血清固定。结论:潜伏梅毒由于受到其隐蔽的临床特征的影响,难以早期发现,潜伏梅毒可以传播患者周围的人群,而且其潜在作用对患者健康危害较大。  相似文献   
378.

Background

Erectile Dysfunction (ED) is one of the major social problems causing significant distress in men. Despite the increasing difficulty in management, knowledge, and understanding of factors responsible for its development are important for prevention and care.

Objectives

To assess the prevalence and risk factors for ED among men in Niger Delta Region of Nigeria, in order to determine its contextual variables.

Methods

Subjects included 400 male patients attending the general outpatients'' clinic (GOPC) of the University of Uyo Teaching Hospital. Respondents completed the abridged version of the International Index of Erectile Function (IIEF-5).

Results

A total of 166 (41.5%) subjects had ED; 66 (16.5%) had mild; 32 (8.0%) mild to moderate; 24 (6.0%) moderate; while 45 (11.3%) had severe 37 (9.2%) resulted from hypertension and its medications; 29 (7.3%) from diabetes; 49 (12.2%) from a combination of both and their therapies (P=0.044); 24 (6.0%) had history of previous surgery; while for 27 (6.8%) it was from undiagnosed medical conditions (p=0.001). The ED increases with age and is more among married and educated men.

Conclusion

ED is a common problem among men in Niger Delta region. Therefore, efforts must be made to reduce the incidence by dealing with the factors responsible for its development.  相似文献   
379.

Objectives

To determine the relative frequency of prostate cancer among surgical specimens, and among prostate specimens received at the pathology department ,University Hospital Calabar.

Methods

Histology records were reviewed for the following: total number of histology specimens received; total number of prostate specimens; total number of prostate cancer; and the total number of cancers in males during the study period. Histology sections 4–5microns thick were cut from paraffin blocks and stained by Haematoxylin and Eosin (H&E). Histopathologic specimens were classified using the grading system of tumour differentiation described by Gleason and associates.

Results

One hundred and twenty three cancers of the prostate were received, constituting 2% of the total surgical specimens and 31% of prostate specimens. Thirty three cases (27%) could not be analyzed; therefore the study is based on 90 prostate cancer specimens. Eighty nine (99%) cases were epithelial tumours (adenocarcinoma.) There was a single mesenchymal tumour (rhabdomyosarcoma) (1%). The commonest grade in this study was the high grade (Gleason grade IV).

Conclusions

We observed that prostate cancer is a common among males (all sites) diagnosed at the University Hospital Calabar, with a peak incidence between the ages of 61 – 70 years (seventh decade).  相似文献   
380.
贾贺  韩萍 《中华糖尿病杂志》2011,19(12):926-930
目的系统评价格列美脲与格列本脲治疗T2DM的疗效。方法计算机检索PubMed、万方等数据库从建库至2010年12月间的有关文献。按Cochrane系统评价的方法评价纳入研究的质量,使用Review Manager4.2软件进行荟萃分析。结果共纳入9个随机对照试验。结果显示:格列美脲在降低HbA1c[P=0.08,加权均数差(WMD)=-0.18,95%CI(-0.39,0.02)]、FPG[P=0.06,WM=-0.46,95%CI(-0.94,0.01)]、餐后血糖[P=O.73,WMD=-0.16,95%CI(-1.08,0.76)]、TC[P=0.22,WMD=-0.2,95%CI(-0.51,0.12)]和TG[P=0.06,WMD=-0.30,95%CI(-0.61,0.01)]方面与格列本脲无差异;在相同血糖水平下,格列美脲组FIns[P〈0.05,WMD=-0.83,95%CI(-1.21,0.45)]及餐后胰岛素[P〈0.05,WMD=-5.94,95%CI(-8.79,-3.10)]升高程度低于格列本脲组;低血糖发生率格列美脲组低于格列本脲组[P〈0.05,RR=0.66,95%CI(0.53,0.81)];在降低BMI方面格列美脲优于格列本脲[P=0.02,WMD=-1.49,95%CI(-2.7,-0.27)]。结论与格列本脲相比,格列美脲在降低血糖的同时,还能改善胰岛素抵抗及减轻体重,且低血糖发生率低,是安全有效的治疗T2DM的药物。  相似文献   
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