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11.

Background  

Genes involved in dopaminergic neurotransmission have been suggested as candidates for involvement in smoking behavior. We hypothesized that alleles associated with reduced dopaminergic neurotransmission would be more common in continuing smokers than among women who quit smoking.  相似文献   
12.
Effects of dietary restriction (DR) on DNA repair capacity of mouse splenocytes after ultraviolet (UV)-induced damage were assessed. Two mouse cohorts received restricted amounts of purified hypocaloric diets; one was minimally restricted (∼75% of the caloric intake of mice fed a commercial diet ad libitum), the other was severely restricted (∼50% caloric restriction). An inverse correlation between age and DNA repair was present in the two cohorts; however, the regression lines of the two cohorts showed different slopes. DR appears to decelerate the age-associated decline of DNA repair capacity, and this delay might account in part for the improved immune function shown by old mice on DR.  相似文献   
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OBJECTIVES: Recurrent glottic carcinoma after radiotherapy (RT) may be managed by open neck or endoscopic surgery. The impact of endoscopic treatment with CO(2) laser for recurrent glottic carcinoma after RT is reported. METHODS: We present the oncologic and vocal outcomes of a retrospective study based on a series of 16 patients with rT1 and rT2 glottic carcinoma who were endoscopically managed between February 1995 and December 1999 after RT failure. All patients were males with a mean age of 68.7 years (range, 50 to 87 years). Before RT, the lesions had been staged as T1 N0 in 11 patients and T2 N0 in 5, and after RT as rT1 N0 in 12 and rT2 N0 in 4. According to the European Laryngological Society classification, a total of 9 transmuscular, 3 total, and 4 extended cordectomies were performed. Mean follow-up was 45 months (range, 9 to 79 months). RESULTS: Endoscopic salvage surgery was successful in 14 patients. One of them developed a second recurrence and was definitively cured with an additional endoscopic procedure. Two of the 16 patients had recurrent disease after salvage laser surgery and died due to progression of disease. Ultimate local control with laser alone at 3 years was 87.1%, according to the Kaplan-Meier method. Laryngeal preservation was obtained in all survivors after endoscopic rescue surgery. Voice analysis showed a clear correlation between the amount of vocal cord tissue resected and decrease of the vocal outcome. CONCLUSIONS: The present series indicates that selected recurrences after primary RT for T1 and T2 glottic carcinoma are eligible for endoscopic salvage surgery with oncologic results comparable to those with open neck procedures but with a lower complication rate and a favorable functional outcome.  相似文献   
14.
BACKGROUND: Management of the gallbladder in patients undergoing laparoscopic Roux-en-Y gastric bypass (LRYGBP) is controversial. We reviewed our experience in patients undergoing LRYGBP without routine gallbladder screening. METHODS: The data of 644 patients who underwent LRYGBP at our institution were analyzed. Preoperative ultrasonography was routinely obtained early in our series and selectively thereafter in patients with suspected symptomatic biliary disease. Cholecystectomy at LRYGBP was performed in symptomatic patients with positive ultrasound findings. Postoperatively, patients with intact gallbladders were prescribed ursodiol for 6 months. RESULTS: Of the 644 patients, 155 (24%) had history of cholecystectomy. A total of 104 patients underwent preoperative ultrasonography. Of the 104 patients, 20 had positive ultrasound findings and symptoms consistent with biliary disease and underwent concomitant cholecystectomy. Twelve patients had positive ultrasound findings and no biliary symptoms and did not undergo cholecystectomy. At a mean follow-up of 26.4 months, only 1 (8.3%) of the 12 patients had required cholecystectomy. Of the 104 patients, 72 had negative ultrasound findings. At a mean follow-up of 21.2 months, 5 of them (6.9%) had required cholecystectomy. The remaining 385 patients did not undergo any gallbladder screening. At a mean follow-up of 14 months, 32 (8.3%) of 385 patients had required cholecystectomy. Compliance with ursodiol for >4 months was only 39%. A time-to-event analysis did not reveal a significant difference in the cholecystectomy rate between asymptomatic patients with preoperative gallbladder screening and patients with no screening. CONCLUSION: Omission of gallbladder screening in asymptomatic patients undergoing LRYGBP is a reasonable approach that spares the patient a potentially unnecessary procedure with all its associated risks.  相似文献   
15.
Summary:  Status epilepticus (SE) is a medical emergency which can lead to significant morbidity and mortality and requires prompt diagnosis and treatment. SE is differentiated into generalized or partial SE on the basis of its electro-clinical manifestations. The guidelines for the management of SE produced by the Italian League against Epilepsy also distinguish three different stages of SE (initial, established and refractory), based on time elapsed since the onset of the condition and responsiveness to previously administered drugs. Treatment should be started as soon as possible, particularly in generalized convulsive SE, and should include general support measures, drugs to suppress epileptic activity and, whenever possible, treatments aimed at relieving the underlying (causative) condition. Benzodiazepines are the first line antiepileptic agents, and i.v. lorazepam is generally preferred because it is associated with a lower risk of early relapses. If benzodiazepines fail to control seizures, i.v. phenytoin is usually indicated, though i.v. phenobarbital or i.v. valproate may also be considered. Refractory SE requires admission to an intensive care unit (ICU) to allow adequate monitoring and support of respiratory, metabolic and hemodynamic functions and cerebral electrical activity. In refractory SE, general anesthesia may be required. Propofol and thiopental represent first line agents in this setting, after careful assessment of potential risks and benefits.  相似文献   
16.
Cancers of the middle umbilical fold are very infrequent, making up 0.1% to 0.7% of all bladder tumors. This type of tumor affects male subjects in 60% to 75% of cases, in the 5th or 6th decade of life. In more than 90% of all cases, the lesion is a mucosecretory adenocarcinoma developing from embryonic remains within the wall of the bladder and respecting the superficial urothelium of the bladder, which is affected only secondarily, contrary to what occurs in the other adenocarcinomas of the bladder. The pathogenesis remains controversial, especially the role of middle umbilical fold patency and of bladder carcinogens. The diagnosis is most often established late, because of a long clinical latency. It is mainly based on ultrasonography and computed tomography. Explorations of the bladder are useful only at an advanced stage. The prognosis is very poor, survival at 5 years ranging from 6.5% to 25% according to the authors. The treatment is mainly surgical. Only extensive exeresis with partial cystectomy extending to the peri- and supravesical environment, including the peritoneum and the umbilicus, and associated with pelvic lymphadenectomy may give some hope. Chemotherapy and radiation therapy, either alone or complementary, are disappointing. The prognosis may be improved only by an early diagnosis.  相似文献   
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The intestinal absorption of molybdenum in healthy human volunteers has been measured by simultaneous oral and intravenous administration of the stable isotopes 95Mo and 96Mo, and the results were analysed using the convolution integral technique. The results showed that molybdenum ingested in liquid form was rapidly and totally absorbed into the circulation under ordinary intake regimes. The rates and extent of absorption were lower for composite meals, and also for increasing levels of administration. This information can be helpful in the application of the new ICRP model of the human alimentary tract.  相似文献   
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