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991.
ObjectiveTo determine the impact of sleep-disordered breathing (SDB) on survival in patients with hypertrophic cardiomyopathy (HCM) following septal myectomy.Patients and MethodsPatients with obstructive HCM undergoing septal myectomy from 2007 to 2016 were reviewed. Those who had an overnight oximetry test within 6 months before myectomy were included in analysis. Oxygen desaturation index was examined continuously and also categorically (SDB [>5/h] and severe SDB [>15/h]).ResultsA total of 619 of 1500 patients undergoing septal myectomy had overnight oximetry tests. Sleep-disordered breathing (oxygen desaturation index >5/h) was identified in 338 (54.6%) patients, and among those patients, 117 (18.9%) were classified as severe. Patients with SDB were older, had greater body mass index and body surface area, were more likely to have arterial hypertension and atrial fibrillation, and had an increased E/e’ ratio on Doppler echocardiography. Notably, there was no difference in preoperative resting left ventricular outflow tract pressure gradient between patients with SDB and those with normal overnight oximetry (55 (interquartile range: 25 to 86) mm Hg versus 52 (interquartile range: 21 to 85) mm Hg; P=.29). There was no difference in age-adjusted survival among patients with normal oximetry compared with those with mild SDB (hazard ratio: 0.98; 95% CI: 0.45 to 2.17), and severe SDB (hazard ratio: 1.06, 95% CI 0.42 - 2.71).ConclusionSleep-disordered breathing is present in more than half of patients with obstructive HCM in whom septal myectomy is indicated, and is mainly associated with aging, overweight, and male sex. However, SDB does not alter survival following septal myectomy.  相似文献   
992.
目的 探讨硝酸甘油在妊娠高血压综合征(妊高征)治疗中的作用。方法 选择妊高征妇女(中、重度)100例,随机分为硝酸甘油治疗组(实验组)50例,硫酸镁治疗组(对照组)50例。分别测定治疗前后血清胱抑素C浓度、甲襞微循环、脐动脉收缩期与舒张期比值(S/D)及阻力指数、血压和24h尿蛋白。结果 ①两组血清胱抑素C值及24h尿蛋白治疗后均降低,治疗前后差异有显著性(P〈0.01);②实验组治疗后甲襞微循环及血压显著降低(P〈0.05),而对照组则无明显变化;③两组治疗前后S/D值及阻力指数差异有显著性(P〈0.05)。结论 ①硝酸甘油能够改善妊高征患者的微循环状态及肾功能,降低血压及胎儿、胎盘血循环阻力;②硝酸甘油在改善微循环及降低血压方面比硫酸镁效果好。  相似文献   
993.
Abstract: The plasma ratio of each neutral amino acid (tryptophan (TRP), tyrosine (TYR), valine, isoleucine, leucine (LEU) or phenylalanine) to the sum of the other neutral amino acids was measured in 16 : manic and 14 : depressed patients. In the manics, there was a correlation between the psychomotor activity and the plasma TRP and LEU ratios. In the depressives, the depressed mood, retardation and global severity were correlated with the TRP ratio. The zotepine responders showed an increase in the TRP ratio after treatment. In the mianserin responders, the TYR ratio, which was high before the treatment, decreased to the normal range after the treatment. But, the plasma amino acid ratios remained unchanged in the patients treated with lithium carbonate or amitriptyhe. These results suggest that, in manic-depressive illness, there might be abnormalities in the metabolism of neutral amino acids, mainly of TRP and TYR, and that the plasma TRP and TYR ratios might be important indicators for determining the efflcacy of some drugs.  相似文献   
994.

Purpose

To evaluate safety and clinical efficacy of embolization for management of bleeding after hepatic radiofrequency (RF) ablation.

Materials and Methods

From January 2000 to December 2014, 5,196 patients with 9,743 tumors underwent 8,303 RF ablation sessions. Of these patients, 62 experienced bleeding after hepatic RF ablation; 15 patients (12 men and 3 women; mean age 62 y; range, 49–76 y) underwent embolization and composed the final study cohort. Tumors were hepatocellular carcinomas in 13 (87%) patients and metastatic adenocarcinomas from colorectal cancer in 2 (13%) patients. Mean number of tumors was 1.5 (22 nodules; range, 1–3). Tumor locations were segment I (n = 1), segment II (n = 2), segment III (n = 1), segment IV (n = 1), segment V (n = 3), segment VI (n = 5), segment VII (n = 1), and segment VIII (n = 9). Mean tumor size was 2.3 cm (range, 0.9–5 cm).

Results

Median time interval between presentation and angiography was 22 hours (mean 38.4 h; range, 3–168 h). On angiography, contrast extravasation with or without pseudoaneurysm was seen in all 15 patients; 14 patients underwent transarterial embolization, and 1 patient underwent percutaneous transhepatic portal vein embolization. Successful hemostasis was achieved in all patients. There was no rebleeding within 30 days after embolization. No embolization-related major complications were observed.

Conclusions

Embolization is safe and effective for controlling bleeding related to hepatic RF ablation without the need for surgery.  相似文献   
995.
目的 :探讨共刺激分子CD80 /CD86与自然流产的关系。方法 :采用双标记流式细胞分析技术检测自然流产小鼠模型CBA/J×DBA/ 2脾脏及肠系膜淋巴结内 (MLN)抗原递呈细胞MΦ表面CD80 /CD86的表达情况 (n =10 ) ,以正常妊娠小鼠模型CBA/J×BALB /c为对照 (n =5 )。结果 :1、自然流产模型组脾脏内表达CD80MΦ含量为 1.82±0 .4 1% ,与正常妊娠模型组的 1.64%± 0 .61%差异无显著性 (P >0 .0 5 ) ,而表达CD86MΦ含量在自然流产模型组中为 2 .34%± 0 .67% ,明显低于正常妊娠模型组的 5 .98%±2 .4 3% (P <0 .0 5 ) ;2、自然流产模型组MLN内表达CD80MΦ含量为 10 .2 0 %± 5 .4 2 % ,明显高于正常妊娠模型组 1.5 8%± 0 .70 % ,差异有显著性 (P <0 .0 5 ) ,而表达CD86MΦ含量在自然流产模型组中为 1.4 6%± 0 .5 7% ,明显低于正常妊娠模型组 3.96%± 0 .39% (P <0 .0 0 1)。结论 :抗原递呈细胞表面共刺激分子CD80 /CD86的表达异常在自然流产的发病中起重要作用  相似文献   
996.
997.
Autosomal dominant holoprosencephaly is a rare but well documented entity and it can be the result of mutations in the Sonic Hedgehog gene (SHH). The transmitting parent may be normal or have a single maxillary central incisor. We describe a skewed sex ratio among the transmitting parents with SHH mutations, with more mothers than fathers having the mutation (p=0.002). The mechanism underlying this skewed sex ratio is not clear; the SHH mutations do not involve triplet repeats, imprinting is plausible but untested, and there is no evidence that the risk of holoprosencephaly is greater among males carrying such a mutation (p=0.15). We considered the possibility that males with such a mutation are at greater risk of other malformations outside the central nervous system, which could reduce their reproductive fitness. To avoid ascertainment bias in identifying children with various malformations in kindreds with familial holoprosencephaly, we reviewed the reports of people with single maxillary central incisor and no other congenital malformations. Of the 16 cases identified, 13 were female (p=0.0085). We suggest that boys with mutations associated with autosomal dominant holoprosencephaly may be at greater risk of major malformations outside the central nervous system than girls.  相似文献   
998.
建立了以功效系数为目标函数的数学模型,对注射容量为2000cm^3,合模力为600t的外翻式注射机合模机构进行了优化计算。  相似文献   
999.
《Radiography》2020,26(3):234-239
IntroductionDCE-MRI is established for detecting prostate cancer (PCa). However, it requires a gadolinium contrast agent, with potential risks for patients. The application of DIR-MRI is simple and may allow cancer detection without the use of an intravenous contrast agent by differentially nullifying signal from normal and abnormal prostate tissue, creating contrast between the cancer and background normal prostate. In this pilot study we gathered data from DIR-MRI and DCE-MRI of the prostate for an equivalence trial. We also looked at how the DIR-MRI appearance varies with the aggressiveness of PCa.MethodDIR-MRI and DCE-MRI were acquired. The images were assessed by an experienced Consultant Radiologist and a novice reporter (Radiographer). The potential PCa lesions were quantified using a lesion to normal ratio (LNR). Radiological pathological correlation was made to identify the MRI lesions that represented significant PCa. A Wilcoxon sign rank was used to compare DCE-LNR and DIR-LNR for PCa containing lesions. Pearson's correlation was used to look at the relationship between DIR-LNR and PCa grade group (aggressiveness).ResultsDCE-LNR and DIR-LNR were found to be significantly different (Z = −5.910, p < 0.001). However, a significant correlation was found between PCa grade group and DIR-LNR.ConclusionDIR and DCE sequences are not equivalent and significant cancer is more conspicuous on the DCE sequence. However, DIR-LNR does correlate with PCa aggressiveness.Implications for practiceWith the correlation of PCa grade group with DIR-LNR this may be a useful sequence in evaluation of the prostate; stratifying the risk of there being clinically significant PCa before biopsy is performed. Furthermore, given that DIR-LNR appears to predict PCa aggressiveness DIR might be used as part of a multiparametric MRI protocol designed to avoid biopsy.  相似文献   
1000.
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