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81.
BACKGROUND: This study investigated the utility of the alveolar - arterial oxygen pressure difference (AaDO (2)) in predicting the short-term prognosis of acute pulmonary embolism (PE). METHODS AND RESULTS: This study retrospectively enrolled 114 consecutive patients with acute PE, diagnosed by either spiral computed tomography or high probability ventilation - perfusion lung scans. During the first 24 h of admission, all patients had initial artery blood gas collected under room air. Patient exclusion criteria were chronic lung disease, septic emboli, and moderate and low probability lung scans. Patients were assigned to 2 groups based on either 30-day death or a 30-day composite event. Receiver operating characteristic analyses was used to determine the AaDO(2) cut-off value for predicting primary and composite endpoints. Statistical analysis demonstrated significant differences in AaDO(2) between the 30-day composite endpoint group and the 30-day composite event-free survival group (p=0.012). The AaDO(2) had a strong trend between the 30-day death group and the survival group (p=0.062). The best cut-off value for AaDO(2) was 53 mmHg and using this, the positive predictive value for 30-day death was 25% and the negative predictive value was 92%. For the 30-day composite endpoint, the positive predictive value for AaDO(2) was 35%, and the negative predictive value was 84%. In this study, thrombocytopenia was also an indicator of poor prognosis for patients with acute PE. CONCLUSION: The AaDO(2) measurement is a highly useful and simple measurement for predicting short-term prognosis in patients with acute PE. It has high negative predictive value and moderate positive predictive value for 30-day death and 30-day composite event. Aggressive thrombolytic treatment strategies should be considered for patients with an initial poor prognostic parameter (ie, AaDO(2) >or=53 mmHg).  相似文献   
82.
This work describes a new approach to multipoint Dixon fat-water separation that is amenable to pulse sequences that require short echo time (TE) increments, such as steady-state free precession (SSFP) and fast spin-echo (FSE) imaging. Using an iterative linear least-squares method that decomposes water and fat images from source images acquired at short TE increments, images with a high signal-to-noise ratio (SNR) and uniform separation of water and fat are obtained. This algorithm extends to multicoil reconstruction with minimal additional complexity. Examples of single- and multicoil fat-water decompositions are shown from source images acquired at both 1.5T and 3.0T. Examples in the knee, ankle, pelvis, abdomen, and heart are shown, using FSE, SSFP, and spoiled gradient-echo (SPGR) pulse sequences. The algorithm was applied to systems with multiple chemical species, and an example of water-fat-silicone separation is shown. An analysis of the noise performance of this method is described, and methods to improve noise performance through multicoil acquisition and field map smoothing are discussed.  相似文献   
83.
小儿重复肾合并其他尿路畸形(附60例报告)   总被引:5,自引:0,他引:5  
60例重复肾中,48例合并输尿管口异位,7例合并输尿管囊肿,4例伴巨大输尿管积水,5例合并肾发育不良,1例为肾积水。年龄4个月~13岁。临床表现:滴沥性尿失禁48例,尿路感染10例,腹部包块6例,排尿困难5例,尿道口有肿物脱出4例。诊断主要依靠IVU。58例经手术治疗,其中51例作患侧上肾部及输尿管切除,7例行患侧肾切除。术后除1例尿内仍有异常外,均恢复满意。  相似文献   
84.
针药并用,针刺人中、百合、涌泉、合谷,中药内服疏风情热,表里双解,止痉退烧,双管齐下治疗24例小儿高热惊厥,经治疗均获痊愈。  相似文献   
85.
目的探讨颅咽管瘤术后水钠代谢紊乱的原因和最佳处理方式。方法对102例经胼胝体切开穹窿间入路切除巨大颅咽管瘤的病人,记录术后尿量、血电解质、抗利尿激素(ADH)、醛固酮(ALD)、皮质醇水平,比较术后激素水平变化与水、钠代谢紊乱的关系。结果本组均出现水、钠代谢紊乱,术后2周完全恢复52例,4周基本恢复33例,6周恢复12例,需长时间人工调整电解质水平5例。术后ADH、ALD和皮质醇的不足是导致术后水钠代谢紊乱的主要原因。结论颅咽管瘤切除术后水、钠代谢紊乱与手术损伤下丘脑有关,紊乱类型与ADH、ALD和醛固酮的缺乏情况有关;及时给予相应激素及对症治疗,可获满意疗效。  相似文献   
86.
目的:观察局部光化学疗法(Psoralen plus UVA,PUVA)治疗儿童白癜风的临床疗效及安全性.方法:采用小型UVA灯(电压220V,电流0.34A,功率25.4w,主波峰长36 5nm,辐照度为1 070uw/cm2)治疗56例白癜风患儿,30次为一个疗程,共观察3个疗程.结果:第一疗程、第二疗程及第三疗程结束后临床显效率分别达39.29%、48.21%和5 5.36%,未发现明显不良反应,其中病程短、局限性及面颈部白癜风患儿疗效佳.结论:局部PUVA治疗儿童白癜风安全、有效、不良反应小,小型UVA灯具有疗效好、治疗方便的优点.  相似文献   
87.
目的 探讨亚低温治疗高温高湿环境下重型颅脑损伤的护理方法。方法 高温高湿环境下的重型颅脑损伤患者60例,随机分为亚低温治疗组和对照组。规范护理程序,严密观察病人生命体征变化,采取积极护理措施,减少并发症。结果 亚低温治疗24h后颅内压逐渐下降,脑组织PO2逐渐上升,伤后3个月亚低温治疗组的良好率明显高于对照组(P〈0.05),而死亡率明显低于对照组(P〈0.01)。结论 精心护理有助于改善亚低温治疗的高温高湿环境下重型颅脑损伤病人的预后。  相似文献   
88.
BACKGROUND AND PURPOSE: The potential risk of prolongation of treatment time in cervical cancer has been reported for many low-dose rate (LDR) studies, with an estimated loss of local control ranging from 0.3 to 1.6% per day of treatment prolongation. Since the treatment schedule for fractionated high-dose rate intracavitary brachytherapy (HDRICB) is not directly comparable with that for low-dose rate studies, this report aims to evaluate the adverse effect of treatment prolongation specifically for cervical cancer treated with HDRICB. MATERIAL AND METHODS: From September 1992 to December 1997, 257 patients diagnosed with uterine cervical cancer (35 Ib, 26 IIa, 122 IIb, 10 IIIa, 57 IIIb, 7 IVa), who underwent external radiotherapy combined with between two and four courses of HDRICB and a minimum of 3 years of follow-up (median 57 months), were analyzed. Treatment consisted of irradiation of the whole pelvis with 44-45 Gy consisting of 22-25 fractions by 5 weeks, with the dose boosted to 54-58 Gy (with central shielding) for patients diagnosed as FIGO stage IIb-IVa bilateral parametrial disease. HDRICB was performed using an Ir-192 remote afterloading technique at 1-week intervals. The standard prescribed dose for each course of HDRICB was 7.2 Gy to point A for three insertions (before July 1995), or 6.0 Gy to point A for four insertions (after July 1995). Total prescribed point A doses (external beam radiotherapy+HDRICB) ranged from 58 to 71.6 Gy (median, 65.6 Gy) for stage IB-IIA, while analogous dosage for larger lesions (stage IIb-IVa) ranged from 59 to 75.6 Gy (median, 65.6 Gy). Kaplan-Meier and multivariate analyses were used to test the effect of treatment time on pelvic control rate (PCR) and cause-specific survival (CSS) at 5 years. RESULTS: Median treatment time was 63 days. For all stages of disease, the 5-year CSS and PCR were significantly different comparing treatment times of less than and greater than or equal to 63 days [83% and 65% (P=0.004], 93% and 83% (P=0.02), respectively]. These associations were also significant for stage Ib/IIa [97% and 79% (P=0.01), and 100% and 87% (P=0.02), respectively), but not for stage IIb [75% and 72% (P=0.79), and 93% and 87% (P=0.83), respectively] or stage III [66% and 49% (P=0.2), and 83% and 72% (P=0.21), respectively]. Multivariate analysis identified three prognostic factors for CSS, stage (P<0.001), tumor response to external RT (P=0.001), and overall treatment time (OTT; P=0.006). Prognostic factors for pelvic failure were stage (P<0.001), tumor response to external RT (P=0.001), and OTT (P=0.03). Prolongation of treatment time resulted in a daily decrease in pelvic control rate of 0.67% overall, and 0.43% for stage Ib-IIa, 0.57% for stage IIb, and 0.73% for stage III patients. CONCLUSION: Analysis of the data from the current study demonstrates that the adverse effect of treatment prolongation was observed later in the treatment course for the high-dose rate (HDR) series compared to the LDR analog, however, treatment-time prolongation still negatively influenced the cause-specific survival and pelvic control rate for both dosage groups.  相似文献   
89.
目的 建立高效液相色谱法测定蜂丁麻滴眼剂中盐酸麻黄碱含量的方法。 方法 采用YWGC18分析色谱柱 ( 4 6mmID× 2 5 0mm ,粒径 10 μm) ,C18保护柱 ( 4 6mmID× 5mm ,粒径 10 μm) ,流动相 10 %乙腈 ( 0 5 %三乙胺 ,磷酸调pH3 0 ) ,流速 1 0ml/min ,检测波长 2 0 8nm ,测定对照品和样品色谱图 ,记录盐酸麻黄碱色谱峰面积 ,计算其含量。 结果 盐酸麻黄碱的理论板数为 10 0 0 0。回归方程 :y =90 5 878 16 15 1738x ,r=0 9999,线性范围 0 4 0 32~ 1 6 13μg。平均回收率为 99 2 % (RSD1 6 % )。 结论 该法操作简便 ,结果准确 ,可用于测定蜂丁麻滴眼剂中盐酸麻黄碱的含量  相似文献   
90.
PCR-SSCP法检测结核分枝杆菌耐药性   总被引:10,自引:0,他引:10  
目的:探讨耐多药结核分枝杆菌耐药基因突变与耐药性的关系以及聚合酶链反应-单链构象多态性分析(poly merase chain reaction-single strand cinfomlation polymorphism,PCR-SSCP)方法的临床应用价值。方法:用PCR-SSCP方法检测58株结核分枝杆菌临床分离株katG,rpoB,rpsL基因突变并与常规药敏试验检测结果进行对比。结果:经常规药敏试验检测,58株结核分枝杆菌临床分离株中共有41株耐药,其中,耐异烟肼(INH)为35株,高耐药株27株;耐利福平(RFP)为31株,高耐药株24株;耐链霉素(SM)有31株,高耐药株26株。同时耐3种药物的有21株(51.2%),耐2种药物的14株(34.1%),单耐药株6株(14.6%).PCR-SSCP方法对58株临床分离株katG,rpoB,rpsL基因突变的检测率为40%(23/58),45%(26/58),38%(22/58),其中检出3个基因同时突变的有13株(32%),2种基因突变的12株(29%),1种基因突变的有10株(23.8%).常规药敏试验与PCR-SSCP法检出结核分枝杆菌同时耐3种药物的符合率为61.9%(13/21),检出耐2种药物的符合率为85.70k,(12/14),检出耐1种药物的符合率为50%(3/6).高耐药株中突变率为80.5%(62/77),低耐药株中突变率为60%(12/20).结论:PCR-SS-CP方法对耐2种以上药物的结核杆菌检出率较高,且耐药基因突变率随着耐药浓度增高而增高。将PCR-SSCP法与药敏试验联合应用可互相弥补,已成为临床指导用药的好方法。  相似文献   
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