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排序方式: 共有371条查询结果,搜索用时 31 毫秒
1.
目的:通过超声热疗配合常规放疗治疗晚期恶性肿瘤的临床研究,评价超声热疗的疗效及与疗效有关的加热参数。材料和方法: 对17 例晚期恶性肿瘤的17 个病灶用常规放疗加超声热疗。放疗用直线加速器外照射,每次2 Gy、周5 次, 总剂量40~70 Gy。热疗在放疗后30 m in 内进行,每周加热1~2 次,每次加温时间 60 m in,6~8 次一疗程。全例病人每次加温时实测肿瘤内温度。结果:在可评价的13例中,CR 23.1% (3/13)、PR 46.2% (6/13)、NC 23.1% (3/13)、PD 7.7% ( 1/13) , 有效率(CR+ PR)为69.3% 。肿瘤中心部温度达到42.5℃以上的累积时间和总加热次数是决定疗效的重要参数。在17 例患者的 89 次加温中,副作用的发生率相对较低。结论:使用超声热疗配合放疗,只要实现满负荷加温,进一步提高肿瘤的局部控制率是完全可能的  相似文献   
2.
Lamivudine, a nucleoside analogue, has been used widely as an effective antiviral agent for the treatment of patients with chronic hepatitis B virus (HBV) infection. However, the YMDD motif mutation of HBV polymerase resistant to lamivudine occurs very frequently after long term therapy. We developed an oligonucleotide chip for the detection of YMDD motif mutants resistant to lamivudine and investigated the prevalence of the mutants in patients with chronic HBV infection who had not been treated by lamivudine before. Forty patients who had not been treated with lamivudine were included in this study. Serum samples were tested by the oligonucleotide chips designed for detection of wild-type YMDD motif, M552V and M552I. Samples were confirmed by restriction fragment length polymorphism (RFLP) and direct sequencing. M552I mutants were detected by the oligonucleotide chips in 7.5% (3/40) of chronic HBV infected patients (2 chronic hepatitis and 1 cirrhosis). The results were in accordance with those of RFLP. YMDD motif mutants occur as natural genome variabilities in patients with chronic HBV infection who had not been treated with lamivudine before. Oligonucleotide chip technology is a reliable and useful diagnostic tool for the detection of mutants resistant to antiviral therapy in chronic HBV infection.  相似文献   
3.
妊娠期糖尿病与瘦素水平变化的临床研究   总被引:4,自引:0,他引:4  
目的 探讨瘦素水平与妊娠期糖尿病 (GDM)发病关系以及对其胎儿生长发育的影响。方法 采用放射免疫法测定GDM孕妇 2 0例 ,糖耐量减低 (IGT)孕妇 2 2例 ,正常孕妇 2 5例血清及其新生儿脐血的瘦素水平 ,同时测定这三组孕妇的胰岛素、C肽水平 ,并测量孕前体重指数和孕期体重增加指数 ,分析其与瘦素之间的关系。结果 GDM孕妇血清瘦素、胰岛素和C肽水平明显高于IGT组及正常组 (P <0 .0 0 1)。脐血瘦素水平与胎儿体重呈正相关 (P <0 .0 5 ) 。孕妇血清瘦素水平与胎儿体重无相关。孕妇血清瘦素水平与脐血瘦素水平无相关。GDM孕妇血清瘦素与孕前体重指数明显相关 (P <0 .0 5 ) ,与孕期体重增加指数无相关。结论  (1)GDM孕妇血清瘦素水平明显高于正常孕妇 ,故瘦素可作为监控GDM的指标之一。(2 )GDM孕妇瘦素水平与脐血瘦素水平虽然不相关 ,提示胎儿瘦素是自身产生 ,但母亲糖尿病也可以影响胎儿产生更多的瘦素。  相似文献   
4.
目的研究厦门市手足口病的流行特征并探讨季节性时间序列(seasonal autoregressive integrated moving average,SARIMA)模型拟合厦门市手足口病发病趋势预测的可行性。方法选取2011—2013年6家医院报告的手足口病10 540例,利用SPSS19.0对厦门市手足口病的发病情况进行流行病学分析,通过取自然对数、差分等方法对手足口病月发病数序列进行平稳化,然后进行模型参数的估计、检验,最优模型的筛选,最后进行预测分析。计量资料采用χ2检验,P0.05为差异有统计学意义。结果 2011—2013年厦门市手足口病的年平均发病率为97.37/10万,4—7月和9月有两个发病高峰,病例主要分布于5岁以下儿童,占所有病例数的93.85%;病原构成以其他肠道病毒为主,占42.9%,其次为肠道病毒71型(enteriovirus 71,EV71)占39.7%,柯萨奇病毒A6(coxsackie virus A6,Cox A6)仅占17.3%;SARIMA(0,1,0)(1,1,0)12较好地拟合了厦门市手足口病的月发病数据,预测效果良好。结论厦门市手足口病的发病率较高,可以用SARIMA模型进行短期预测,进而指导各项防控措施。  相似文献   
5.
Objective: To explore the genetic effect of the GH receptor (GHR) on obesity and related metabolic parameters in Hong Kong Chinese adolescents. Context: Obesity is a growing global epidemic. Increasing evidence suggests that the GH‐IGF‐I axis plays an important role in regulating adiposity and insulin sensitivity. Design: We examined the associations of genetic variants of GHR with serum IGF‐I and IGFBP‐3 levels as well as obesity‐related metabolic traits in Hong Kong Chinese adolescents. Patients: Nine hundred and eighty‐one randomly selected Hong Kong Chinese adolescents from 14 schools. Measurements: We genotyped 17 single nucleotide polymorphisms (SNP) at GHR and measured serum IGF‐I and IGFBP‐3 levels as well as obesity‐related metabolic traits including fasting plasma glucose, insulin and lipid levels. Results: There were significant associations between rs4410646 and the body composition (P = 0·0044) and blood pressure factor scores (P = 0·00017). Carriers of the CC genotype had lower body mass index, percentage body fat, waist and hip circumferences than AC and AA genotype carriers (P = 0·00030–0·0094). There was also association between rs7703713 and the IGF‐I activity factor score (P = 0·0033). The GA and AA carriers of rs7703713 had higher serum IGF‐I, higher serum IGFBP‐3 and higher IGF‐I/IGFBP‐3 molar ratio (P = 0·00069–0·025). Haplotype analysis did not increase the significance of associations. Conclusion: Our results support the role of GHR gene polymorphisms in modulating adiposity and IGF‐I activity in adolescents. Examination of interactions of these SNPs with lifestyle, environmental and perinatal factors may provide further insights into their long‐term effects on obesity and metabolic risks.  相似文献   
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8.
INTRODUCTIONHypoglycaemia constitutes a significant barrier to achieving glycaemic control with insulin in both Type 1 (T1DM) and Type 2 diabetes mellitus (T2DM). The International Operations Hypoglycaemia Assessment Tool (IO HAT) study was designed to determine the incidence of hypoglycaemia in insulin-treated patients with T1DM and T2DM.METHODSThe IO HAT study retrospectively and prospectively assessed the incidence of hypoglycaemia in patients with insulin-treated diabetes mellitus in nine countries. This sub-analysis included patients from Singapore with T1DM or T2DM who were aged ≥ 21 years and had completed two self-assessment questionnaires (SAQ1 and SAQ2).RESULTSOf the 50 T1DM and 320 T2DM patients who completed the SAQ1, 39 T1DM and 265 T2DM patients completed SAQ2; 100% and 90.9%, respectively, experienced at least one hypoglycaemic event prospectively. The incidence rates of any hypoglycaemia were 49.5 events per patient-year (EPPY) and 16.1 EPPY for T1DM and T2DM patients, respectively, in the four-week prospective period. Hypoglycaemia rate did not differ in terms of glycated haemoglobin level. The vast majority of T1DM or T2DM patients (92.0% and 90.7%, respectively) knew the overall definition of hypoglycaemia before study participation, although over half of the patients (T1DM 54.0%, T2DM 51.9%) defined hypoglycaemia based only on symptoms.CONCLUSIONHigh proportions of insulin-treated patients with diabetes mellitus in Singapore reported hypoglycaemic events prospectively, showing that they had underreported hypoglycaemic episodes retrospectively. Patient education can help in improving hypoglycaemia awareness and its management in the region.  相似文献   
9.
10.

Background

A second-look endoscopy is routinely performed after endoscopic submucosal dissection (ESD) in many institutions, although the need is questionable. Additional hemostatic procedures might be necessary for the post-ESD ulcer with a high risk of bleeding. We investigated the predictive factors for post-ESD ulcers with a high risk of bleeding.

Methods

Second-look endoscopy was performed on the day following ESD. The post-ESD ulcers were categorized into two risk groups according to the Forrest classification: high-risk ulcer stigma (type I and IIa) and low-risk ulcer stigma. We analyzed the risk factors associated with high-risk ulcer stigma and late delayed bleeding.

Results

During the study period, 616 ESD procedures were performed. Second-look endoscopy revealed that the incidence of high-risk ulcer stigma post-ESD was 15.1 %. Early and late delayed bleeding rates were 3.7 and 1.9 %, respectively. Multivariate analysis revealed that submucosal fibrosis and nausea were significantly related to high-risk ulcer stigma after ESD. Multivariate analysis revealed that surface erosion, location of the lesion, and high-risk ulcer stigma identified by second-look endoscopy were significantly associated with late delayed bleeding.

Conclusions

The effective use of selective second-look endoscopy will help limit unnecessary procedures. Submucosal fibrosis and nausea were risk factors associated with high-risk ulcer stigma after ESD.  相似文献   
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