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1.

Background

Laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding all lead to substantial weight loss in obese patients. Long-term weight loss can be highly variable beyond 1-year postsurgery. This study examines and compares the frequency distribution of weight loss and lack of treatment effect rates after laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding.

Methods

A total of 1,331 consecutive patients at a single academic institution were reviewed from a prospectively collected database. Preoperative data collected included demographics, body mass index, and percent excess weight loss. Postoperative BMI and %EWL were collected at 12, 24, and 36 months. Percent excess weight loss was analyzed by the percentiles of excess weight lost, and the distribution of percent excess weight loss was evaluated in 10% increments. Lack of a successful treatment effect was defined as <25% excess weight loss.

Results

Of the 1,331 patients, 72.4% (963) underwent laparoscopic Roux-en-Y gastric bypass, 18.3% (243) laparoscopic sleeve gastrectomy, and 9.4%(125) laparoscopic adjustable gastric banding. Mean percent excess weight loss was greatest for laparoscopic Roux-en-Y gastric bypass, followed by laparoscopic sleeve gastrectomy, and then by laparoscopic adjustable gastric banding at every time point: at 2 years mean percent excess weight loss was 77.9± 24.4 for laparoscopic Roux-en-Y gastric bypass, 50.8 ± 25.8 for laparoscopic sleeve gastrectomy, and 40.8± 25.9 for laparoscopic adjustable gastric banding (P < .0001). The rates of a successful treatment effect s for laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding were 0.9%, 5.2%, and 24.3% at 1 year; 0.3%, 11.1%, and 26.0% at 2 years; and 1.0%, 25.3%, and 30.2% at 3 years. At 1 year, the odds ratio of lack of a successful treatment effect of laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass was 6.305 (2.125–19.08; P?=?.0004), the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass was 36.552 (15.64–95.71; P < .0001), and the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy was 5.791 (2.519–14.599; P < .0001). At 2 years, the odds ratio for laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass increased to 70.7 (9.4–531.7; P < .0001), the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass increased to 128.1 (16.8–974.3; P < .0001), and the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy decreased to 1.8 (0.9–3.6; P?=?.09).

Conclusion

This study emphasizes the existing variability in weight loss across bariatric procedures as well as in the lack of a treatment effect for each procedure. Although laparoscopic adjustable gastric banding has the greatest rate of a lack of a successful treatment effect, the rate remained stable over 3 years postoperatively. Laparoscopic sleeve gastrectomy showed a doubling in the rate of a lack of a successful treatment effect every year reaching 25% at year 3. The rates for lack of a successful treatment effect for laparoscopic Roux-en-Y gastric bypass remained stable at about 1% for the first 3 years postoperatively.  相似文献   
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Data on the bacteriological findings, diagnostic measures and clinical course of 875 patients with bacterial meningitis are presented. Findings from the medical records and from a follow-up questionnaire survey of 667 of these cases revealed no significant difference between patients treated with antibiotics before admission (pretreated) and those who were not treated before admission (non-pretreated) with respect to clinical condition on admission, mortality and late sequelae. Pretreatment was, however, associated with a longer duration of symptoms. Apart from cases due to Neisseria meningitidis, there were no significant differences in diagnostic findings between pretreated and non-pretreated cases. In the group of pretreated meningococcal patients, however, positive blood cultures, pleiocytosis in the cerebrospinal fluid (CSF) and positive cultures from sites other than blood and CSF were less frequent than in the non-pretreated cases.  相似文献   
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Encainide, a new benzanillide derivative with high potency and a good therapeutic/toxic ratio, was evaluated with the use of standard His bundle recording techniques to determine its effects on the cardiac conduction system in closed chest animals. Twenty mongrel dogs weighing 18 to 29 kg were anesthetized with 4 percent chloralose and classified into groups: group 1, a control group and groups 2,3, and 4, which were given 0.3, 0.9 and 2.7 mg/kg body weight, respectively, of encalnide In an intravenous infusion over a 15 minute period. Plasma concentration, blood pressure, surface electrocardiogram and atrlal and His bundle electrograms were recorded before, during and after drug infusion for a total of 120 minutes. Heart rate, A-H and H-V intervals, the QRS complex and Q-Tc interval were measured every 5 minutes during sinus rhythm and with constant atrial pacing. In addition, sinus nodal recovery time and atrial, atrioventrlcular (A-V) nodal and left ventricular refractory periods were measured before and immediately after infusion and every 30 minutes for 2 hours. Peak plasma concentration averaged 450 ng/ml in group 2,1,300 ng/ml in group 3 and 4,000 ng/ml in group 4. Blood pressure was not altered at any dose level throughout the study. The QRS complex and H-V interval were significantly prolonged (P < 0.005) at doses of 0.9 mg/kg and greater. These effects correlated well with plasma concentration. There was no significant change in heart rate, corrected sinus nodal recovery time, A-H interval, Q-Tc Interval atrial, A-V nodal or left ventricular refractory period. It is concluded that, unlike other antiarrhythmic agents, encainide prolongs His-Purkinje system conduction without significantly affecting conduction or refractoriness of other parts of the cardiac conduction system in animals.  相似文献   
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目的 探讨术中经食道超声心动图(Transesophageal Echocardiography,TEE)在急性Stanford A型主动脉夹层(AAD)手术中的应用价值。 方法 选取经全主动脉CTA诊断为ADD的患者41例,术前行TEE检查,根据TEE检出主动脉根部受累情况分为三组:夹层未累及主动脉根部组(A组)16例,主动脉根部轻-中度受累组(B组)9例,主动脉根部重度受累组(C组)16例。均行术前TEE检查观察主动脉根部形态、夹层受累情况,包括主动脉瓣叶形态、功能,测量并比较各组主动脉瓣环内径、主动脉窦部内径、窦管交界内径及可显示升主动脉段的最大内径,观察冠状动脉起始段形态;术后TEE即刻观察手术效果。并将TEE结果与术中所见进行比较。结果 41例患者术前TEE对升主动脉内撕裂的内膜片显示阳性率为100%。B、C组主动脉窦部内径均大于A组,C组主动脉窦部内径大于B组,差异均有统计学意义(P<0.05);A、B、C三组患者主动脉瓣环及升主动脉内径比较差异均无统计学意义。经手术证实,术前TEE诊断夹层累及冠状动脉的特异性为62.5%,敏感性为56%。术后TEE可评估人工主动脉瓣或修复主动脉瓣形态、功能,以及人工血管、冠状动脉等吻合情况。结论 术前TEE能准确评估AAD主动脉根部及冠状动脉受累情况,术后TEE可即刻评估手术效果,具有重要的临床应用价值。  相似文献   
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To study the effects of digoxin on regional left ventricular performance, continuous ventricular dynamics were assessed in nine patients with stable coronary disease. Computer-assisted analysis of the fluoroscopic motion of surgically implanted mid wall myocardial markers was used. The markers define six minor ventricular radii and outline the left ventricle. One and one-half hours after administration of 1 mg of intravenous digoxin, mean velocity of circumferential fiber shortening for all segments increased 19 percent, from 0.67 +/- 0.06 to 0.78 +/- 0.06 circumference/sec (P less than 0.01) and ejection fraction increased 4.5 percent, from 0.50 +/- 0.03 to 0.53 +/- 0.03 (P less than 0.05). Segmental velocity of circumferential fiber shortening, total segmental shortening and early segmental systolic shrtening increased in 83 percent to 91 percent of normal segments, depending on which index was used. Only 45 to 55 percent of initially abnormal segments benefited from digoxin. In general, segmental dyssynergy increased even when net ventricular function was enhanced. These results suggest that in pateints with chronic left ventricular contraction abnormalities due to coronary disease, deterioration of performance in abnormal regions after administration of digoxin may result from increased stress imposed by increased afterload and by improved segmental dynamics in more normal areas.  相似文献   
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