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81.
Twenty-nine infants (2-4 months old), with pathological gastroesophageal reflux assessed by 24-h esophageal pH monitoring, were studied. Cisapride or placebo was randomly added to positional treatment, prone-antiTrendelenburg position, which was applied to all infants. The pH monitoring was repeated after 13-16 days of treatment and revealed a significant improvement in both groups for most parameters. But the number of reflux episodes lasting longer than 5 min and the total number of reflux episodes had not decreased significantly in the placebo group. Only in the number of reflux episodes lasting longer than 5 min was improvement during treatment significantly greater in the cisapride group. This suggests cisapride both prevented reflux and improved esophageal clearance. These results suggest that in addition to other therapeutic measurements, such as positional treatment (which was previously demonstrated to be effective in this age group), cisapride might be of benefit in the treatment of gastroesophageal reflux disease.  相似文献   
82.
BACKGROUND: Executive dysfunctions have been studied as a potential endophenotype associated with the genetic basis of autism. Given that recent findings from clinical and molecular genetic studies suggest that autism and obsessive-compulsive disorder (OCD) could share a common pattern of heritability, we assessed executive functions as a possible common cognitive endophenotype in unaffected family members of individuals with either autism or OCD. METHODS: Five tests assessing executive functions (Tower of London, verbal fluency, design fluency, trail making and association fluency) were proposed to 58 unaffected first-degree relatives (parents and siblings) of probands with autism and 64 unaffected first-degree relatives of OCD patients. Results were compared with those of 47 healthy controls matched for age, sex, and level of education. RESULTS: In the Tower of London test, both groups of unaffected relatives showed significantly lower scores and longer response times compared with controls. No differences were observed between autism and OCD relatives and healthy controls in the four other tasks (verbal fluency, design fluency, trail making test and association fluency). CONCLUSIONS: Our findings show the existence of executive dysfunction in the unaffected first-degree relatives of probands with OCD, similar to those observed in the relatives of patients with autism. These results support and extend previous cognitive studies on probands indicating executive dysfunctions in autism and OCD. Planning and working memory processes could thus represent a common cognitive endophenotype in autism and OCD that could help in the identification of genes conferring vulnerability to these disorders.  相似文献   
83.
N-(4-Cyanophenyl)-N'-(2-carboxyethyl)urea (2), an analogue of suosan [1,N-(4-nitrophenyl)-N'-(2-carboxyethyl)urea], is a known high-potency sweetener derived from beta-alanine. Sulfonic and phosphonic acid analogues of 2 were prepared to develop structure-activity relationships through modification of the carboxylic acid region of this family of sweeteners. Neither of the carboxylic acid replacements resulted in sweet analogues. However, we found that N-(4-cyanophenyl)-N'-[(sodiosulfo)methyl]urea (7) is an antagonist of the sweet taste response. The bitter taste response to caffeine, quinine, and naringin was also antagonized. Antagonist 7 was found to inhibit the sweet taste perception of a variety of sweeteners. Antagonist 7 had no effect on the sour or salty taste response.  相似文献   
84.
The α-inhibin gene has been shown in knockout mouse models to be a suppressor of granulosa tumorigenesis in the mouse. To determine if α-inhibin has the same function in humans, we have assessed the frequency of loss of heterozygosity (LOH) of the α-inhibin gene locus on chromosome 2q in 17 human granulosa cell tumors and 36 epithelial ovarian cancers. LOH was detected in 12 of 36 (33.3%) epithelial tumors but in only 1 of 17 (6%) granulosa cell tumors. These data suggest that in contrast to the suggestions from the mouse model α-inhibin does not function as a granulosa cell tumor suppressor gene in the human. Furthermore, analysis of the TP53 gene in the granulosa cell tumors failed to detect either LOH or point mutations, indicating that they have a developmental pathway distinct from that of epithelial ovarian tumors.  相似文献   
85.
Suicidal behavior is a common and important problem among alcohol dependent patients. The study was designed to examine risk factors for attempting suicide in 499 alcohol dependent patients. Those who had attempted suicide (N = 198) were more likely to be female, report a family history of suicidal behavior, report more childhood trauma, report greater levels of aggressive behavior, began heavy drinking earlier, and were more likely to have received antidepressant medication. Logistic regression analysis showed that gender, family history, and childhood sexual abuse history made significant and independent contributions to the risk of a suicide attempt. Thus, developmental, personality, family history, social, and comorbidity risk factors may differentiate alcohol dependent patients who have attempted suicide from those who have not.  相似文献   
86.
87.
We report the simultaneous measurement of esophageal wall layer thickness and intraluminal pressure in the sheep esophagus using a miniature suction device incorporating a high-frequency ultrasound transducer and a manometry system. Transnasal placement of the device into the distal esophagus of a conscious sheep allowed observation of 133 swallowing events during three trials, each lasting from 45 to 60 minutes. In a fourth trial, 11 sequential dry and 23 sequential wet swallows were compared. Maximum manometric pressure, esophageal wall layer thickness, and duration of contraction were measured. All swallowing events produced simultaneous increases in intraluminal pressure and esophageal wall thickness. Mean maximal pressures were lower for dry swallows (18 ± 2.1 mm Hg) than wet swallows (22 ± 3.0 mm Hg) (p < .01). Thickness of the inner (circular) muscle layer increased above baseline by 124% for dry swallows and 161% for wet swallows (p < .01). We conclude that thickening of the esophageal inner (circular) muscle layer may be important in the generation of intraluminal esophageal pressure in the sheep esophagus. (Gastrointest Endosc 1995;41:582-6.)  相似文献   
88.
89.
Pneumatic dilation is the initial therapy for primary esophageal achalasia. Recently, polyethylene balloon (Rigiflex) dilators have been used with varying success and complication rate. We performed a total of 47 dilations in 29 consecutive patients with achalasia using the Rigiflex dilators. The 3.0-cm balloon was always used first. If there was no symptomatic response, a 3.5-cm balloon was used after 4–8 wk. If there was still no symptomatic response after 4-8 wk, a 4.0-cm dilator was used. Eighteen (62%) patients were successfully dilated with a 3.0-cm balloon only. Of 11 patients not responding to a 3.0-cm balloon, five were dilated successfully with a 3.5-cm balloon. Of six patients not responding to a 3.5-cm balloon, four were successfully dilated with a 4.0-cm balloon dilator. Two patients eventually required surgery. The overall success with Rigiflex balloon dilator was achieved in 27 of 29 (93%) patients. There were no complications. We conclude that pneumatic dilation for esophageal achalasia performed in a graded fashion starting with Rigiflex 3.0-cm balloon dilator has a high success rate without complications in patients with achalasia.  相似文献   
90.
D Roy  J G Liehr 《Cancer research》1988,48(20):5726-5729
In an attempt to characterize metabolism enzymes of the estrogen-induced kidney tumor in male Syrian hamsters, the activities of enzymes involved in drug and glutathione metabolism were determined in tumor tissue. Kidney tumors were induced in male Syrian hamsters by treatment with estradiol for 8 months. Cytochrome P-450 and cytochrome b5 concentrations in tumors were below detectable levels. However, when cytochrome P-450-mediated oxidation was analyzed by product formation assays, the oxidation of E-diethylstilbestrol to diethylstilbestrol-4',4"-quinone by tumor microsomes was 10-20% of the rate found in control microsomes. In kidney tissue surrounding estrogen-induced tumors, cytochrome P-450 and b5 contents were 50-60% less than those in untreated kidney. Activities of reducing enzymes of drug metabolism (cytochrome P-450, cytochrome b5 and NADH:cytochrome c reductases), glutathione metabolism enzymes (glutathione peroxidase, glutathione transferase, glutathione reductase, and gamma-glutamyl transpeptidase), and free radical scavenging enzymes (superoxide dismutase, catalase, and quinone reductase) in tumor were significantly lower than in untreated kidney tissue. The activities of these enzymes in renal tumor surrounding tissue were between those observed in tumor and control kidney. Glucose-6-phosphate dehydrogenase activity was increased by 50% in surrounding tissue and 430% in tumor compared to values in untreated controls. The decreased enzyme activity levels in hormone-exposed tissue surrounding tumors likely represented an adaptation of this tissue to the neoplastic environment induced by chronic estrogen treatment.  相似文献   
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