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151.
The growth hormone-releasing hormone receptor (GHRHR) is a member of the family of G protein-coupled receptors that is expressed on pituitary somatotrope cells and mediates the actions of GHRH in stimulating growth hormone (GH) synthesis and secretion. We report that the Ghrhr gene is located in the middle of mouse chromosome 6 in the same region as the little mutation. Mice homozygous for this mutation have reduced GH secretion and a dwarf phenotype. A missense mutation was identified in the extracellular domain of the little GHRHR that disrupts receptor function, suggesting that the growth deficit in these mice results from a defect in the GHRHR. Similar alterations in GHRHR might explain some isolated GH deficiencies in humans. 相似文献
152.
153.
A 23 year old previously healthy man was stabbed in the anterior chest. This resulted in a ventricular septal defect and complete atrioventricular (A-V) block. The electrocardiogram revealed complete A-V block with a QRS pattern of right bundle branch block. His bundle recordings 26 days later revealed A-V dissociation with split His potentials (P-H1 interval of 100 msec and H2-V interval of 40 msec). During the study the escape QRS shifted from right to left bundle branch block with H2 potentials still preceding each QRS interval with H2-V intervals of 40 msec. A permanent pacemaker was implanted because of persistent congestive heart failure and bradycardia due to A-V block. The patient subsequently became asymptomatic. He died suddenly 3 1/2 years later. Pathologically there were sizable openings in both the tricuspid and mitral valve substance and a ventricular septal defect involving the pars membranacea and part of the adjacent muscular septum. Serial sections of the conduction system revealed total destruction and fibrous replacement of the bifurcation and beginning of the right and left bundle branches and subtotal fibrous replacement of the branching bundle. Thus, the bifurcation of the bundle of His was totally absent at autopsy despite apparent electrophysiologic evidence of its existence 26 days after the stab wound. A possible explanation for this discrepancy is the subsequent fibrosis of the bifurcation produced by hemodynamic changes at the lower margin of the ventricular septal defect. 相似文献
154.
HO Williamson PB Underwood A Kreutner JF Rogers RS Mathur HR Pratt-Thomas 《Canadian Metallurgical Quarterly》1976,126(5):579-585
Six patients with a total of nine gonadoblastomas are presented; three--and possibly a fourth--had dysgerminomatous overgrowth which was massive in two patients. Calcification detected by abdominal films was present in three sufficient for preoperative diagnosis. All patients were found to have a Y stem line on peripheral leukocyte chromosome cultures except one patient, who had a 46 XX/45 XO karyotype. She was found to have Y chromatin bodies in the germ cells of her tumor which was in a normal ovary found at exploration for an ectopic pregnancy. Three were found in virilized phenotypic females investigated for amenorrhea, and two for therapy of pelvic masses due to dysgerminomatous overgrowth. Y chromatin studies are reported on gonadal tissue. 相似文献
155.
156.
HR Gilbert 《Canadian Metallurgical Quarterly》1975,8(2):129-140
Speech samples were obtained from 10 miners with diagnosed black lung disease and 10 nonminers who had never worked in a dusty environment and who had no history of respiratory diseases. Frequency, intensity and durational measures were used as a basis upon which to compare the two groups. Results indicated that four of the six pausal measures, vowel duration, vowel intensity variation and vowel perturbation differentiated the miners from the nonminers. The results indicate that black lung disease may affect not only respiratory physiology associated with speech production but also laryngeal physiology. 相似文献
157.
Three hundred 8-year-old Shorthorn and Santa Gertrudis bulls, with a 47% incidence of Tritrichomonas foetus infection in the 30 surveyed, were removed from a herd of approximately 6000 cows and replaced by 325 two-year-old Brahman bulls. A sample of 50 of the replacement bulls was examined at introduction and found to be uninfected. After 2 years, the incidence of infection in a sample of 80 of the replacement bulls was 4%. The results suggests that a major reduction in incidence of infection in extensively managed herds might be achieved by the exclusive use of young bulls for mating. 相似文献
158.
Two experiments were conducted to determine the effect of acute heat stress on late-stage chicken embryos. Embryos were incubated at a normal control temperature (37.5 degrees C.) for 16 days and were then subjected to 40.6, 43.3, 46.1 or 48.9 degrees C. for various periods of time in another incubator of the same type. At the end of the stress period all embryos were placed back into the control incubator for the remainder of the incubation period. Exposure of embryos for 24 hours to a temperature of 40.6 degrees C, caused no major detrimental effects on hatchability. Exposure for 6 hours to the temperature of 43.3 degrees C, caused a decrease in hatchability with a severe decline in hatchability occurring after 9 hours of exposure. Exposure to 46.1 degrees C. for 3 hours or 48.9 degrees C for 1 hour killed all embryos. Chicks which hatched following a severe heat stress had a high incidence of clubbed, wiry down and exhibited an unsteady gait. 相似文献
159.
HR Hawthorne MA Wood BS Stambler RJ Damiano KA Ellenbogen 《Canadian Metallurgical Quarterly》1993,16(12):2241-2249
Implantable cardioverter defibrillator (ICD) implantation is rapidly becoming accepted as primary therapy for malignant ventricular arrhythmias. Many patients undergoing ICD implantation are on concomitant antiarrhythmic drugs to decrease shock frequency, slow tachycardia rate, and suppress supraventricular arrhythmias. Amiodarone is a potent antiarrhythmic agent that is also frequently used in the treatment of patients with refractory ventricular arrhythmias. Ten to forty percent of patients undergoing ICD implantation will also be taking amiodarone. It has been reported to cause pulmonary toxicity in about 5% of patients per year. Acute amiodarone toxicity presenting as adult respiratory distress syndrome has been reported much less frequently. Although perioperative morbidity due to amiodarone has been described, the risk, predictability, and consequences of acute pulmonary toxicity from amiodarone in patients undergoing ICD implantation have not been previously described. We reviewed the records of 99 consecutive patients undergoing ICD implantation at our institution from October 1987 to April 1992. Thirty-nine patients were taking 480 +/- 230 mg of amiodarone (median 400 mg, lower 20th percentile 400 mg, upper 80th percentile 800 mg) for 291 +/- 554 days prior to ICD implantation. Ten patients taking amiodarone developed acute pulmonary toxicity clinically manifesting as diffuse pulmonary infiltrates on chest radiography and adult respiratory distress syndrome with hypoxia (arterial pO2 < 60 mmHg) without evidence of pneumonia or elevated pulmonary capillary wedge pressure (PCW < or = 15 mmHg). Of the 60 patients not taking amiodarone none developed adult respiratory distress syndrome.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
160.
NV Dawson AF Connors T Speroff A Kemka P Shaw HR Arkes 《Canadian Metallurgical Quarterly》1993,13(3):258-266
Our current knowledge of risk factors for Alzheimer's disease is limited and primarily addresses early-onset disease. This study aimed to determine the risk factors for late-onset Alzheimer's disease using a case-control approach. Ninety-eight cases and 216 controls were gathered from an ongoing population survey on aging and dementia in Stockholm (the Kungsholmen Project). We found a high relative risk (3.2; 95% confidence interval, 1.8-5.7) with the presence of at least one first-degree relative affected by dementia. Among all the other risk factors, alcohol abuse (relative risk, 4.4; 95% confidence interval, 1.4-13.8) and manual work (relative risk for men of 5.3; 95% confidence interval, 1.1-25.5) emerged as positively associated. No clear association was found with a family history of Parkinson disease, advanced parental age at index delivery, season of birth, or previous head trauma. In conclusion, our data suggest that the main risk factor for late-onset Alzheimer's disease is a family history of dementia, as has been previously reported for early-onset disease. Moreover, alcohol abuse and occupational exposure might play a specific role for this form of the disease. 相似文献