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51.
Temporary pacemaker use during coronary arteriography 总被引:1,自引:0,他引:1
The risk of life-threatening ventricular arrhythmias complicating coronary angiography is reportedly increased in patients in whom temporary righ ventricular pacemakers are used. Placement of the temporary pacing electrode in the right atrium or vena cava during angiography theoretically removes from the vulnerable ventricle a source of mechanically or electrically induced ventricular arrhythmias. This hypothesis was evaluated in 7,648 consecutive patients who underwent cardiac catheterization with selective coronary angiography, including 103 with life-threatening ventricular arrhythmic complications. The prevalence of ventricular arrhythmias was 6.4 times greater in patients with temporary pacemakers than in those without (7% vs 1.1%, respectively, p less than 0.001). Analysis of 369 cardiac catheterizations concurrently using temporary pacemakers revealed a greater than 4-fold decrease in the frequency of ventricular arrhythmias when the pacing electrodes were located in the right atrium or vena cava rather than the right ventricle (2% vs 9%, respectively, p less than 0.01). No significant difference in indications for temporary pacing could be distinguished between the groups based on location of the pacing electrode or occurrence of ventricular arrhythmias. These findings confirm that there is an increased risk of ionic contrast agent-induced ventricular arrhythmias in patients with chronic underlying conduction disturbances undergoing coronary angiography with concurrent right ventricular temporary pacemakers. This risk can be significantly decreased by placing the pacing electrode in the right atrium or vena cava. 相似文献
52.
P Slater S McConnell S W D'Souza A J Barson M D Simpson A C Gilchrist 《Brain research. Developmental brain research》1992,65(2):157-160
The binding of D-[3H]aspartate to the specific uptake site for the excitatory amino acids glutamate and aspartate was measured in homogenates of temporal lobe cortex taken at postmortem from 76 human infant and adult brains. Binding levels were very low in brains of preterm and term infants but increased rapidly during the first 20 postnatal weeks to reach levels which exceeded those in adult brains. Linear regression analysis which compared the amount of D-[3H]aspartate binding with the age of the infant, showed a positive correlation up to 25 postnatal weeks. Saturation analysis showed that the maximum number of D-[3H]aspartate binding sites (Bmax) in temporal cortex from infants aged 20 postnatal weeks was 3 times greater than the number of sites in adult brain. The findings show that the number of excitatory amino acid uptake sites, which may be associated in part with presynaptic terminals, increase in number rapidly after birth. Furthermore, the data may indicate that a slow regression of excitatory amino acid terminals occurs during the later stages of brain development. 相似文献
53.
王文志 杨定焯 蒋建军 吴涛 程晓光 周琦 卓铁军 张华俦 项静 王洪复 区品中 刘建立 徐苓 黄公怡 黄琪仁 HS Barden LS Weynan KG Fqukner 孟迅吾 《中国神经再生研究》2008,12(50):9997-10000
背景: 不同地区骨峰值和标准差不同,对骨质疏松诊断率有较大影响。探讨建立一完整数据库为中国人骨质疏松诊断准确性提供依据。
目的:探讨青年人腰椎骨密度和标准差正常参考值影响骨质疏松症检出率的程度。
设计、时间及地点:调查分析,于1997-01/1999-12分别在北京、上海、广州、南京、嘉兴和成都市完成。
对象:采用前瞻性及回顾性方法对全国6个中心骨密度参考数据库中11 418人进行调查统计分析;男3 666人,女7 752人;年龄20岁~90岁;分别来自北京(2 385人)、广州(1 178人)、上海(1 404人)、南京(2 938人)、成都(1 425人)、嘉兴(2 088人),受试者来源于社区调查、健康体检和健康志愿者。
方法:用GE-Lunar公司的DXA仪测量骨密度,调查全国6个中心11 418人L2~L4腰椎后前位和髋部骨密度,建立了骨密度参考数据库。6个中心的仪器内部精度0.3%~0.7%,仪器间的精度1.1%。
主要观察指标:①6个中心不同年龄组腰椎骨密度分布。②青年人群骨密度及其标准差值对骨质疏松症检出率的影响。
结果:中国汉族女性以腰椎进行骨质疏松症诊断的青年人群的骨密度和标准差值,6个中心,最大差值分别为0.098 g/cm2和0.027 g/cm2。用6个中心及总体各自的青年人平均骨密度和标准差值为参考标准,对同一人群计算T-score和获得的骨质疏松症检出率不相同;发现青年人平均骨密度每变化0.01 g/cm2,则骨质疏松症检出率变化1.6%(呈正相关),其标准差值每变化 0.01 g/cm2,则骨质疏松症检出率变化4%(呈负相关)。
结论:青年人平均骨密度和标准差值不同引起骨质疏松症检出率也不相同。为了让不同中心的骨质疏松症检出率有可比性,建议同一个类型的骨密度仪,同一个种族,同一个地区用一个设计较完善大样本的参考数据库,以其青年人正常参考值计算T-score。 相似文献
54.
Lekamge DN Lane M Gilchrist RB Tremellen KP 《Journal of assisted reproduction and genetics》2008,25(11-12):515-521
Purpose
This retrospective study was carried out to evaluate whether increasing the starting dose of FSH stimulation above the standard dose of 150 IU/day in patients with low predicted ovarian reserve can improve IVF outcomes.Method
A total of 122 women aged less than 36 years in their first cycle of IVF were identified as having likely low ovarian reserve based on a serum AMH measurement below 14 pmol/l. Thirty five women were administered the standard dose of 150 IU/day FSH, while the remaining 87 received a higher starting dose (200–300 IU/day FSH). There were no significant differences in age, BMI, antral follicle count, serum AMH, FSH or aetiology of infertility between the two dose groups.Results
No significant improvement in oocyte and embryo yield or pregnancy rates was observed following an upward adjustment of FSH starting dose. While increasing the dose of FSH above 150 IU/day did not produce any adverse events such as OHSS, it did consume an extra 1,100 IU of FSH per IVF cycle.Conclusion
The upward FSH dose adjustment in anticipation of low ovarian reserve can not be advocated as it is both expensive and of no proven clinical value. 相似文献55.
Objective To investigate the clinical and pathological characteristics of pauci-immune crescent glomerulo~nephritis (PICGN) in Chinese patients. Methods During 13 years (1985-1998), 6400 patients underwent non-transplanting renal biopsy. Twenty-four patients were diagnosed as PICGN. All clinical and laboratory data of these patients were collected from the patients’ records and used for detailed analysis. The diagnosis is based on clinico-pathologic findings. Results Of the 24 patients, 16 were females and 8 were males, with median age of 33 years (ranged 10-76 years). Microscopic polyarteritis (MPA) (33.3%) and systemic vasculitis (8.3%) were the secondary diseases. The incidence of PICGN was 0.38% in renal biopsies and 22.9% in crescentic glomerulonephritis. Clinically, most patients (75.0%) showed rapidly progressive nephritis with enlarged kidneys. At onset, gross hematuria was noted in 58.3% of patients, hypertension in 45.8%, nephrotic syndrome in 41.7%, and oliguria in 25.0%. However, systemic symptoms were rare except for anemia. Pathologically, necrosis of glomerular capillaries (62.5%), infiltration of monocytes and neutrophil cells in glomeruli (66.7%), and vasculitis in the interstitium (53.3%) were observed. In addition, glomerulosclerosis was noted in 45.8%, severe tubular atrophy in 83.3% and interstitial fibrosis in 75.0%. Anti-neutrophil cytoplasmic antibodies (ANCAs) were positive in 52.2%. All patients except two received intensively immunosuppressive therapy. Sixteen patients were available for long-term follow up (median 29.8 months, range 8-92 months). Twelve of them had life-sustaining renal function, four had normal serum creatinine (<124?μmol/L) and only 4 patients were dialysis-dependent. Conclusion PICGN is not rare in China. Early diagnosis and administration of immunosuppressive therapy, particularly in patients with rapidly progressive glomerulonephritis (RPGN), are important for good prognosis. 相似文献
56.
Dr. F. Kristian Storm MD Kennedy W. Gilchrist MD Thomas F. C. S. Warner MD David M. Mahvi MD 《Annals of surgical oncology》1995,2(1):43-48
Background: The overexpression of heat shock protein 27 (hsp-27) in early-stage breast cancer is associated with histopathologic features of poor prognosis and clinically with an increased probability of disease recurrence. Hsp-27 is overexpressed in 25% of invasive ductal carcinomas (IDC); however, its distribution in ductal carcinoma in situ (DCIS) and DCIS associated with IDC has not been investigated. We postulated that hsp-27 might be detected and variably expressed in DCIS and, like HER-2/neu oncoprotein expression, might be a tumor-specific marker worthy of future clinical investigation.
Methods: To test these hypotheses, the distribution of hsp-27 in noncomedo and comedo DCIS, and DCIS associated with IDC, was evaluated by immunohistochemistry and compared with HER-2/neu expression within the same cancers.
Results: Hsp-27 was overexpressed in 28 of 47 (60%) cases of DCIS; expression in pure DCIS was 16 of 24 (67%), and 12 of 23 (50%) in DCIS associated with IDC. Hsp-27 expression by in situ and invasive components of the same neoplasm were concordant in 22 of 23 (95%) cases tested. Comedo variants appeared to have somewhat higher hsp-27 expression than noncomedo DCIS, whether or not there was an associated IDC. These results are reminiscent of HER-2/neu oncoprotein expression in DCIS and DCIS associated with IDC observed by others. However, although 4 of 22 (18%) cancers containing DCIS + IDC expressed HER-2/neu, no relationship with hsp-27 expression in the same cancers was observed.
Conclusions: We found a high incidence of hsp-27 overexpression in DCIS and in DCIS associated with IDC. This rate is twice that previously observed in IDC alone. Hsp-27 expression is independent of HER-2/neu expression. 相似文献
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60.
Y-H Cha H Lee LS Santell & RW Baloh 《Cephalalgia : an international journal of headache》2009,29(5):550-555
The aim of this study was to determine the association of benign recurrent vertigo (BRV) and migraine, using standardized questionnaire-based interview of 208 patients with BRV recruited through a University Neurotology clinic. Of 208 patients with BRV, 180 (87%) met the International Classification of Headache Disorders 2004 criteria for migraine: 112 migraine with aura (62%) and 68 without aura (38%). Twenty-eight (13%) did not meet criteria for migraine. Among patients with migraine, 70% experienced headache, one or more auras, photophobia, or auditory symptoms with some or all of their vertigo attacks, meeting the criteria for definite migrainous vertigo. Thirty per cent never experienced migraine symptoms concurrent with vertigo attacks. These met criteria for probable migrainous vertigo. Among patients without migraine, 21% experienced either photophobia or auditory symptoms with some or all of their vertigo attacks; 79% experienced only isolated vertigo. The age of onset and duration of vertigo attacks did not differ significantly between patients with (34 ± 1.2 years) and patients without migraine (31 ± 3.0 years). In patients with migraine, the age of onset of migraine headache preceded the onset of vertigo attacks by an average of 14 years and aura preceded vertigo by 8 years. The most frequent duration of vertigo attacks was between 1 h and 1 day. Benign recurrent vertigo is highly associated with migraine, but a high proportion of patients with BRV and migraine never have migraine symptoms during their vertigo attacks. Other features such as age of onset and duration of vertigo are similar between patients with or without migraine. 相似文献