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71.
Comparing ICD Implantation with and Without Intraoperative Defibrillation Testing. Introduction: The need to perform defibrillation testing (DT) at the time of implantable cardioverter defibrillator (ICD) insertion is controversial. In the absence of randomized trials, some regions now perform more than half of ICD implants without DT. Methods: During the last year of enrolment in the Resynchronization for Ambulatory Heart Failure Trial, a substudy randomized patients to ICD implantation with versus without DT. Results: Among 252 patients screened, 145 were enrolled; 75 randomized to DT and 70 to no DT. Patients were similar in terms of age (65.9 ± 9.3 years vs 67.9 ± 8.9 years); LVEF (24.7 ± 4.6% vs 23.6 ± 4.6%), QRS width (154.8 ± 23.5 vs 155.8 ± 23.6 ms), and history of atrial fibrillation (5% vs 6%). All 68 patients in the DT arm tested according to the protocol achieved a successful DT (≤25 J); 96% without requiring any system modification. No patient experienced perioperative stroke, myocardial infarction, heart failure (HF), intubation or unplanned ICU stay. The length of hospital stay was not prolonged in the DT group: 20.2 ± 26.3 hours versus 21.3 ± 23.0 hours, P = 0.79. One patient in the DT arm had a failed appropriate shock and no patient suffered an arrhythmic death. The composite of HF hospitalization or all‐cause mortality occurred in 10% of patients in the no‐DT arm and 19% of patients in the DT arm (HR = 0.53, 95% CI: 0.21–1.31, P = 0.14). Conclusions: In this randomized trial, perioperative complications, failed appropriate shocks, and arrhythmic death were all uncommon regardless of DT. There was a nonsignificant increase in the risk of death or HF hospitalization with DT. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1313‐1316, December 2012)  相似文献   
72.
Non-Hodgkin's lymphoma (NHL) is the most common human immunodeficiency virus (HIV)-associated malignancy in hemophiliacs. We studied the incidence and clinicopathologic features of NHL in 3,041 hemophiliacs followed at 18 US Hemophilia Centers between 1978 and 1989. Of the 1,295 (56.6%) who were HIV(+), 253 (19.5%) developed acquired immunodeficiency syndrome (AIDS), of whom 14 (5.5%) developed NHL. Three NHL occurred in HIV(-) hemophiliacs, for a 36.5-fold greater risk in HIV(+) than HIV(-) hemophiliacs (P < .001). The NHL incidence rate was 29-fold greater than in the US population by Surveillance, Epidemiology, and End Results (SEER) estimates (P < .001). Between 0 and 4 lymphomas have been observed per year between 1978 and 1989. At presentation 13 (92.9%) of the HIV(+) NHL were extranodal. Ten were stage IV, 1 stage II, and 3 stage IE. Ten (71.4%) were high-grade, 3 (21.4%) intermediate-grade, and 1 (7.1%) was a low-grade B-cell lymphoma. Epstein-Barr virus (EBV) DNA was detected in 36% by in situ hybridization, including one central nervous system (CNS) lymphoma. The mean CD4 cell count at NHL diagnosis was 64/mm3, the mean latency from initial HIV infection was estimated to be 59 months, and the median survival was 7 months. The incidence of basal cell carcinoma in HIV(+) hemophiliacs was 18.3-fold greater than in HIV(-) hemophiliacs (P < .001) and 11.4-fold greater than in the US population (P < .001). In conclusion, incidence rates of NHL and basal cell carcinoma in HIV(+) hemophiliacs are significantly increased over rates in HIV(-) hemophiliacs and over rates in the US population. Clinicopathologic presentation of NHL in HIV(+) hemophiliacs is similar to that in HIV(+) homosexual men.  相似文献   
73.
Hereditary elliptocytosis (HE) is a heterogeneous disorder of red blood cells frequently associated with abnormal limited tryptic digestion of the alpha I domain of spectrin and impaired spectrin dimer self- association. We studied two related individuals with poikilocytic hereditary elliptocytosis (HE) of different severity. Limited tryptic digestion of spectrin from these individuals showed the presence of a variant alpha I/50b Kd peptide at the expense of the normal alpha I/80 Kd peptide. Amino acid sequence analysis of the abnormal peptide showed that the proteolytic cleavage occurred after the arginine at position 470 of the alpha spectrin chain. Spectrin from these patients had an impaired ability to undergo self-association, as evidenced by increased amounts of spectrin dimers in 4 degrees C extracts of erythrocyte membrane from affected individuals. The polymerase chain reaction was used to study the DNA sequence of the alpha spectrin gene encoding the region of the alpha spectrin chain surrounding the abnormal proteolytic cleavage site. We detected the in-frame deletion of the trinucleotide CAT, encoding histidine 469, two amino acid residues to the N-terminal side of the abnormal proteolytic cleavage site between residues 470 and 471. Similar to many other defects of spectrin associated with HE, this deletion occurs in helix three of repeat 5 of the proposed triple helical model of spectrin repeats.  相似文献   
74.

Background  

More than 50% of hepatitis C viruses (HCV)-infected patients do not respond to the classical Interferon (IFN)/Ribavirin (RBV) combination therapy. The aim of this study was to evaluate the efficacy of retreatment with Peg-Interferon alpha-2b (PEG-IFN alpha-2b) plus RBV, in patients with HCV, genotypes 1 or 3, who were non-responders to the previous standard treatment with IFN/RBV.  相似文献   
75.
高效液相色谱法测定消痰咳片的含量   总被引:2,自引:0,他引:2  
目的:采用反相色谱法同时测定消痰咳片中两种主要成分甲氧苄啶和磺胺体的含量。方法:以乙腈:0.1%H3PO4(15:85)为流动相,检测波长254nm,HPLC法测定含量。结果:试验表明,甲氧苄啶和磺胺林在0.8-8ug范围内呈良好的线性关系,回归方程分别为Y=-1127.1+110.2x(r=0.9994),Y=-1852.3 256.2x(r=0.9996),相对标准偏差分别为2.1%和0.8%。结论:该方法简便、准确、可靠。  相似文献   
76.
目的:考察5种注射剂盐酸林可霉素注射液,盐酸精氨酸注射液,注射用玻璃酸酶,肝素钠注射液和顺铂注射液的细菌内毒素检查法可行性。方法:中国药典细菌内毒素检查法。结果;除d外,其余原液及稀释液均于有干扰作用。结论:d的原液及a的20倍以上稀释液可用灵敏度为0.5EU/ml的鲎试剂作细菌内毒素检查,而b,c和e尚需进一步探讨。  相似文献   
77.
磁性明胶微球体内分布实验研究   总被引:11,自引:0,他引:11  
对磁性明胶微球进行了同位素标记。用γ-闪烁照相技术观察了磁性明胶微球在兔体内的分布。结果表明:靶部位的放射活性加磁场是未加磁场的15倍,而且施加磁场时间长和磁场强度大有利于磁性明胶微球定位于靶区。文中也介绍了自行设计的外加磁场装置。  相似文献   
78.
Patients with the syndrome of chronic daily headache often report migrainous symptoms and consequently are diagnosed as having a primary headache syndrome. We report two cases of idiopathic intracranial hypertension causing chronic daily headache with migrainous features in the absence of associated papilledema.  相似文献   
79.
Summary: Oral ofloxacin has been successfully used in our centres for the primary treatment of peritonitis complicating continous ambulatory peritoneal dialysis (CAPD). In view of the progressive rise in the resistance rate to ofloxacin among peritoneal bacterial isolates, a study was conducted to determine if oral ofloxacin remains a viable first line treatment for CAPD peritonitis in our centres and if the result can be improved by changing from an oral to an intraperitoneal (i.p.) route. In patients on three 2 L daily CAPD exchanges, ofloxacin given at the i.p. dosage of 200 mg loading followed by 25 mg/L of peritoneal dialysate achieved overnight trough peritoneal levels which are at least four times the minimal 90% inhibitory concentration (MIC90) of most bacterial pathogens without significant accumulation in the systemic circulation. This i.p. dosage was therefore chosen for the clinical study and the result was compared to that using ofloxacin given in the oral dosage of 400 mg loading followed by 300 mg once daily as maintenance. of all the recruited episodes, 35 were eligible for analysis. the overall primary cure rate including primary failures and relapses was 55.6% (10/18) in the oral treatment group and 70.6% (12/17) in the i.p. treatment group. the corresponding figures for gram positive bacterial (g +) infections were 36.4% and 50%, for gram negative bacterial (g -) infections were 66.7 and 80% and for culture negative infections were 75 and 80%. In culture positive cases, all treatment failures were due to resistant infections which were observed in 42.3% of all bacterial isolates, 47.1% of g + isolates and 33.3% of g - isolates. Due to the high background level of bacterial resistance among our CAPD population, ofloxacin monotherapy given either by the oral or the i.p. route can no longer be recommended for the primary treatment of CAPD peritonitis.  相似文献   
80.
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