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131.
Moderating effects of meal composition on psychomotor performance impairment and feelings after alcohol were examined in a between-subjects design. Fifty-one male volunteers fasted or received either a high carbohydrate (85% energy) or a high protein (94% energy) meal. Alcohol was administered at a dose to achieve a blood alcohol level (BAL) of 60 mg/100 ml, as a placebo. Subjects performed a dual task of primary tracking and secondary reaction time and a five-choice reaction time task. Feelings were also assessed by rating. The high carbohydrate meal reduced BAL at peak and 2 h after drinking, but a high protein meal had no significant effect. Although performance was impaired by alcohol, neither meal significantly reduced impairment and there was no effect of meal type on performance in the placebo condition. However, alcohol increased rated intoxication and the high carbohydrate meal reduced this effect. Subjects who had consumed high protein meals had more negative affect 2 h after alcohol than did subjects who had consumed high carbohydrate meals or fasted. It is concluded that there is only a weak relationship between BAL and performance impairment and food has only limited effects on impairment, although it reduces BAL.  相似文献   
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Metastases of lung cancer are a major cause of treatment failure. To evaluate the therapeutic efficacy of gene therapy in metastatic lung cancer, we used adenoviral (ADV) mediated transfer of the herpes simplex virus thymidine kinase (HSV-tk) gene and the cytokine gene interleukin-2 (IL-2) to treat a murine model of metastatic lung cancer in the liver. Hepatic metastases were established by intrahepatic implantation of LL2 cells in syngeneic recipient mice. One week after tumor implantation, various replication defective ADV vectors were injected intratumorally. Treatment with a vector expressing the HSV-tk followed by ganciclovir administration with ADV.tk resulted in significant regression of tumor (p<0.01) as well as prolongation of survival (p<0.001). While a vector expressing mouse IL-2 ADV.IL-2 alone was ineffective, combination therapy with HSV-tk resulted in further tumor regression and improvement of animal survival (p<0.05). These results demonstrate that suicide and cytokine genes can be utilized in combination to treat metastatic lung cancer in vivo.  相似文献   
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BACKGROUND: The thalassemias are common in southern China. We determined the prevalence of heterozygous carriers of these genetic disorders in Hong Kong and assessed the feasibility of a community-based screening program. METHODS: An educational and screening program for the thalassemias was carried out in three high schools with a total of 2420 students. Seventy-five percent of the students agreed to undergo screening, which consisted of blood counts, hemoglobin electrophoresis, serum ferritin measurements, and DNA analyses. RESULTS: Of the 1800 blood samples tested, 150 (8.3 percent) had microcytosis (mean corpuscular volume, <80 microm3). Ninety students (5.0 percent) were carriers of alpha-thalassemia, of whom 81 (4.5 percent) were carriers of the Southeast Asian type of deletion, in which both alpha-globin genes on the same chromosome 16 are deleted. Sixty-one students (3.4 percent) were carriers of either beta-thalassemia or the mutation coding for hemoglobin E. Six students were carriers of both alpha- and beta-thalassemias. On the basis of these figures, the estimated numbers of pregnancies in Hong Kong in which the fetus is at risk for homozygous alpha-thalassemia and beta-thalassemia major or intermedia are 145 and 80 per year, respectively. In Hong Kong the actual numbers of women referred for prenatal diagnoses of these disorders are approximately 95 and 40 per year, respectively. CONCLUSIONS: Despite the availability of hospital-based screening and prenatal diagnosis for many years in Hong Kong, many women carrying fetuses at risk for thalassemia are not referred for genetic counseling. A community-based program of education, screening, and counseling is needed in Hong Kong and southern China.  相似文献   
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We report the use of MRI in the diagnosis, follow-up and therapeutic management of three cases of intralabyrinthine Schwannoma. The diagnosis was based on the history and initial and follow-up MRI findings. The main feature suggesting the diagnosis was a nodular intralabyrinthine mass of low signal intensity on T2-weighted images, and high or isointense signal on T1-weighted images (relative to cerebrospinal fluid), which showed contrast enhancement. Follow-up imaging showed growth of the tumour in one patient. One patient underwent surgery for severe tinnitus. To detect these lesions, MRI should be focussed on the inner ear, using thin-section T2-weighted and T1-weighted images before and after contrast medium. MRI allowed informed surgical planning.  相似文献   
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The purpose of this study was to assess the diagnostic value of magnetic resonance cholangiopancreatography (MRCP) in studying the anatomy, sites, and causes of obstructive jaundice. From September 1994 to May 1996 three-dimensional MRCP was performed on 31 patients with abdominal pain and obstructive jaundice with a fast spin-echo T2-weighted pulse sequence. The images were reconstructed using maximal intensity projection, AVERAGE and SURFACE algorithm processing techniques at a graphics workstation. All the reconstructed images were compared with those obtained using conventional cholangiographic techniques, such as endoscopic retrograde cholangiopancreatography, percutaneous transhepatic cholangiography and drainage, and intraoperative cholangiography. The patients' diagnoses included choledochal cyst (13), cholangiocarcinoma (five), choledocholithiasis (four), pancreatic head carcinoma (three), rhabdomyosarcoma (one), papillary Vater carcinoma (one), recurrent gastric carcinoma (one), ascaris (one), and biliary atresia (two). Extrahepatic biliary dilatation was present in all 13 patients with choledochal cyst; the pancreatic ducts and their entrance level to the common bile duct were observed in eight of these patients. The level of obstruction in patients with cholangiocarcinoma was well documented but the biliary tract of one patient with biliary atresia was not identified by MRCP. In one patient with biliary rhabdomyosarcoma, MRCP clearly delineated the extrabiliary extension of the tumor. In a patient with ascaris in the common bile duct an increase in signal intensity inside the digestive tract of the worm denoted fluid in its gut. Lithiasis was shown in all of the four patients with choledocholithiasis. Thus, MRCP is a useful tool in the assessment of biliary tract obstruction and its causes, and is a valuable addition to ultrasonography.  相似文献   
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