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51.
This is a double-blind placebo-controlled study of sustained-release bupropion as a smoking cessation aid in alcoholics undergoing treatment for their alcoholism. Participants (N=58) were enrolled within 1 week of entry into alcohol treatment from community and Veterans Affairs Substance Use Disorder programs. All participants received nicotine patch and were invited to attend a smoking cessation lecture and group. Cigarette smoking and alcohol outcomes were measured at 6 months. Bupropion when added to nicotine patch did not improve smoking outcomes. One third of participants on bupropion reported discontinuing the drug during weeks 1-4. Participants reported cigarette outcomes with nicotine patch that are similar to those seen in the general population. All study participants significantly reduced cigarette use. Comorbid affective disorder or antipersonality disorder did not affect outcomes. Alcohol outcomes were improved in those who discontinued cigarettes.  相似文献   
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53.
Disturbances of visual cognition, visuomotor performance, and visual memory have been described frequently in Huntington's disease (HD). Early stage visual abnormalities could contribute to these deficits. We evaluated visual processing in 20 control subjects who were non-gene carriers at risk for HD, nine presymptomatic gene-positive subjects, and eight subjects with a recent diagnosis of Huntington's disease. Visual perceptual tests of contrast sensitivity and motion discrimination were used to probe early stage visual processing. Extraocular movements were evaluated in a neurologic examination, and the Digit Symbol test was used to test visual motor performance. Contrast sensitivity did not differ among the three groups. Motion discrimination was impaired in HD subjects but not in the presymptomatic gene carriers when compared to gene noncarriers. Among gene carriers, impaired motion discrimination performance was associated with poorer Digit Symbol performance and extraocular abnormalities. These findings suggest that the early stages of HD are associated with disturbances of motion perception as well as disruptions of visual motor and ocular motor performance.  相似文献   
54.
This study evaluated the safety of triple vs single-lumen catheters in intravenous nutrition. Patients who were judged likely to benefit from a triple-lumen catheter were randomized to receive either a single-lumen catheter, with additional peripheral or central venous access as needed, or a triple-lumen catheter. All patients were at increased risk of catheter-related infection because of one or more of the following conditions: > 60 years of age, breakdown of skin integrity, severe underlying illness, diagnosis of acute pancreatitis, recent head or neck surgery, or presence of a preexisting infection. Patients were excluded who had neutropenia, were immunosuppressed, had body burns > 40%, or had contaminated wounds in the subclavicular area. Of 204 patients entered between June 1989 and November 1991, 177 completed the required > or = 7 days of therapy. Seventy-eight of these patients were randomized to a single-lumen catheter and 99 to a triple-lumen catheter. Catheters were inserted and maintained by the Nutrition Support Team. Dressings were monitored daily and changed weekly using a bio-occlusive dressing. When parameters were met for a possible septic episode, simultaneous peripheral and central catheter blood cultures were obtained using the Isolator method. Catheter-related sepsis was considered present if the colony count from a central catheter lumen was > or = 5 times that of the peripheral blood. The incidence of catheter-related sepsis for single-lumen catheters was 2.6% (2 of 78) compared with 13.1% for triple-lumen catheters (13 of 99) (p < .01). No correlation was found with the number of insertion attempts, catheter days, or patient's age.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
55.
Ventilatory requirements during simulated aeromedical transportation were investigated in normal dogs and animals with oleic acid-induced lung injury. Inspired oxygen fractions of 0.21 and 1.0 were used to ventilate the normal and injured dogs, respectively. Both groups were ventilated with a constant-volume piston ventilator. After a control period, animals were exposed to a simulated altitude of 8,000 ft (barometric pressure 564 mm Hg), followed by a second control period at ground level. Both groups of animals had no change in carbon dioxide production, arterial PCO2 or ventilation during exposure to reduced barometric pressure. Systemic blood pressure, heart rate, cardiac output, and lung volume were all lower in oleic acid-injured animals than controls; the alveolar-arterial oxygen difference was larger in the oleic acid group. With altitude exposure, arterial and mixed venous oxygen tensions were decreased in both groups. Adequate gas exchange can be maintained during exposure to altitude even in animals with abnormal function provided that ventilation is constant and the inspired oxygen fraction is increased to compensate for the reduced barometric pressure.  相似文献   
56.
57.
When haemostatic clamps are applied, evidence of injury at the site of clamp application may be seen when the clamp is removed. Rarely, the intima may be disrupted. When a new arterial clamp became available, a study was designed to compare the Martin Titanline arterial clamp (13-143-35, curved arterial clamp) with several other arterial clamps already in use. The Martin clamp is a modified pivot-point, preset-tension, spring-controlled arterial clamp. The closing pressures of several clamps were measured objectively. The injury produced when the clamps were applied to occlude the blood flow on the carotid artery of a dog was assessed by histological study of the excised segments of the arterial wall. Histological cross-sections were prepared from canine carotid artery which had been perfused for 1 h after the clamp had been applied for 1 h. Histological evidence of injury was limited to disruption of the intimal layer and compression of the medial layer. No significant difference between the amount of damage caused by the DeBakey, Satinsky or Martin clamp was identified. When compared to the other varieties of clamp listed above, the Martin clamp had a significantly lower closing pressure (304 g) compared with 580g (Bulldog), 580 g (Satinsky), and 686 g (DeBakey). The Martin clamp was easier to apply, did not obstruct the operative field as readily and had good clamp-retention characteristics throughout the procedure.  相似文献   
58.
J P Grant 《Annals of surgery》1988,207(5):598-603
In a review of 125 percutaneous endoscopic gastrostomies (PEG) and 88 Stamm gastrostomies performed at Duke University Medical Center since 1978, the average operating room time for PEG (50 +/- 20 min) was shorter than for Stamm (96 +/- 26 min) (p less than 0.0001). General anesthesia was administered in only 13% of PEG placements compared with 64% of Stamm gastrostomies. The cost of PEG was about $1000 less than for Stamm gastrostomies. The average time after surgery until use of the feeding tube was 1.8 days for PEG compared with 3.4 days for Stamm (p less than 0.0001). The overall complication rate after PEG was 8.8% (4.0% major) compared with 23.9% for Stamm gastrostomies (10.2% major) (p less than 0.005). PEG reduces operative time, necessity for general anesthesia, expense of insertion, incidence of complications, and requires less recovery time before use. PEG is the procedure of choice for gastric feeding access.  相似文献   
59.
We wished to evaluate the efficacy and safety of a low and an intermediate daily dose of interferon-alpha2b (IFN-alpha2b) with didanosine in patients with acquired immunodeficiency syndrome (AIDS)-associated Kaposi's sarcoma (KS). HIV-seropositive subjects with biopsy-confirmed cutaneous KS were randomized to receive either a low (1 million IU) or an intermediate (10 million IU) dose of IFN-alpha2b once daily with twice daily doses of didanosine. Treatment assignment was stratified by CD4 count. Response, toxicity, changes in CD4 counts, and survival were evaluated. Sixty-eight eligible subjects were accrued, 35 to low-dose and 33 to intermediate-dose IFN-alpha2b. The response rate was 40% in the low-dose group (95% CI, 24-58) and 55% in the intermediate-dose group (95% CI, 36-72) (p = 0.338). The median response duration was approximately 110 weeks in both groups. Intermediate-dose IFN induced grade 3/4 neutropenia more often (21% vs. 3%, p = 0.048) and grade 3/4 toxicity faster (p = 0.0231) and necessitated treatment discontinuation earlier for drug-related toxicities (p = 0.0416) than low-dose IFN. There were no significant differences in survival between the treatment groups. Baseline CD4 count was the only significant factor predicting response. Once-daily low-dose and intermediate-dose IFN-alpha2b induced similar response rates, which were achieved without optimal antiretroviral therapy. The slightly higher response rate in the intermediate-dose group was offset by its significantly poorer tolerance. These findings justify the use of lower, well-tolerated IFN doses for treatment of KS with currently used antiretroviral regimens.  相似文献   
60.
伏尔泰<哲学通信>中的第11封信是<谈种痘>,信中关于种痘史实细节的表述不够准确,原因在于其本人并未亲临现场,没有引征文献,多是得于传闻,甚或出于自己的想象.一些不够准确的表述,虽似无伤大雅,但容易对人痘起源和传播途径方面的研究产生误导,应当加以纠正.关于蒙塔古夫人将人痘接种术带回英国的过程,因国内罕能读到原始文献,有不少以讹传讹,更有必要于此加以澄清.  相似文献   
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