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991.
992.
Although pentagastrin has a tropic action on intestinal mucosa in suckling rat pups, and at weaning a rise in gastrin levels coincides with maturation of the intestinal mucosa, direct correlations of serum gastrin levels and intestinal maturation have yet to be made. Ten-day-old rats were subjected either to antrectomy to produce a 43% decrease in serum gastrin levels or to fundectomy to produce a 319% increase over gastrin levels in rumenectomized or normal animals. These changes were not associated with tropic or adaptive changes in jejunal or colonic mucosa as determined by jejunal and colonic DNA content, jejunal sucrase activity, jejunal villous height, or crypt depths in jejunum and colon at the beginning (day 15), middle (day 21), or end (day 27) of the weaning period. To the contrary, an inverse relation was found between serum gastrin levels and both jejunal mucosal DNA content and sucrase activity as an index of maturation.  相似文献   
993.
Metastatic Crohn's disease (MCD) is a rare extraintestinal manifestation of Crohn's disease characterized by the histologic finding of granulomatous dermatitis at a site noncontiguous to the gastrointestinal tract. An adolescent had MCD of the face that was initially mistaken for severe, treatment-resistant acne. Histopathologic and microbiologic evaluation, combined with clinical examination and response to therapy, ultimately led to the correct diagnosis. Mycobacterium paratuberculosis is a suspected cause of Crohn's disease. Polymerase chain reaction was used to detect genomic DNA specific for the organism in biopsy specimens from the patient's cutaneous lesions. This study failed to demonstrate M. paratuberculosis in the specimens.  相似文献   
994.
995.
Broilers were reared in conditions of hypobaric hypoxia (3500 m altitude) to investigate the development of pulmonary nodules in birds reared in hypobaric hypoxia and judged by clinical observation to be developing broiler pulmonary hypertension syndrome (BPHS); in unaffected birds reared in hypobaric hypoxia; and in birds reared at ambient atmospheric pressure. Gross pulmonary morphometric measurements, packed cell volume, electrocardiogram QRS amplitude and body weight also were compared among the three experimental groups. Results indicate that hypobaric hypoxia alone exercised little influence on the development of pulmonary nodules. Nodule numbers per section and nodule area per section were numerically greater in birds reared in hypobaric hypoxia, but there were no consistent significant differences in nodule numbers in birds which developed BPHS. As expected, absolute lung length, inter-rib distance and lung volume increased significantly with increasing age and size; but when these parameters were expressed as a function of body weight, they decreased with increasing age. Again, intergroup differences were inconsistent. Packed cell volume and electrocardiogram QRS amplitude were significantly increased in birds reared in hypobaric hypoxia.  相似文献   
996.
In 100 patients with lung cancer we have found no significant abnormality in overall HLA antigen frequency when compared to a control sample of 151 random health individuals from the same region, though there was a high relative risk of being HLA-BW22-positive and having lung cancer. There was an increased frequency of HLA-B5 in small-(oat-)cell anaplastic carcinomas (P less than 0.05); HLA-B15 in anaplastic tumours (P less than 0.05); HLA-B40 in Stage III patients (P = 0.05) and a decreased frequency of HLA-B12 in adenocarcinomas (P less than 0.05). In 86 patients followed up for 2 1/2-5 3/4 years after surgery we have been unable to confirm the significant association of HLA-AW19 and/or HLA-B5 with good prognosis as reported by others. The most striking observation was that the frequency of HLA-BW22 was significantly higher in patients alive at least 2 1/2 years after surgery when compared to the control groups (P less than 0.05) and 83% of patients HLA-BW22-positive are alive compared to only 52.5% of lung cancer patients lacking this antigen. However, all the P values become nonsignificant when multiplied by the number of antigens studied, and these observations need further investigation in a large, prospective study.  相似文献   
997.
The results of the first 40 patients, whose pregnancies were terminated using Gemeprost vaginal suppositories are presented. The indication for termination of pregnancy was either fetal abnormality, or fetal death in utero. The mean gestational age was 20.9 +/- 4.4 weeks. 82.5% of patients were delivered within 24 hours, following a mean number of 3.9 +/- 1.3 pessaries. Side-effects were uncommon, and the procedure was well tolerated, with 30% of patients requiring no analgesia, and 60% receiving narcotic analgesia only. The results obtained compare favourably with the overseas experience with this method. Augmentation with oxytocic agents is of questionable value, and routine evacuation of the uterine cavity, under general anaesthesia seems unnecessary. Administration is simple and well tolerated by patients, and this method of pregnancy interruption appears safe, efficient and superior to extra-amniotic infusion of PGF2 alpha.  相似文献   
998.
Dilatation of 23 surgically created gastrointestinal tract stomata in 21 patients has been performed using angioplasty techniques. A success rate of 44% was achieved in nine patients with gastric stapling and Marlex mesh wrapping of the greater curve stoma. In 13 patients with gastric stapling, and either sutured gastro-gastrostomy or roux-en-y gastro-jejunal bypass, a success rate of 77% was achieved. In one patient with a jejunostomy, stenosis dilatation was also successful.  相似文献   
999.
Eight healthy old and 12 healthy young women had event-related potentials (ERPs) recorded during the performance of a memory retrieval task. For each subject the single trial data recorded at Pz were analyzed using Woody's adaptive filter technique. The old subjects differed from the young in several respects: P3 amplitude at Pz was smaller, P3 latency and reaction time (RT) were greater, the relationship between P3 latency and RT was considerably altered. The adaptive filter increased the amplitude of P3 but the age-related amplitude difference persisted, suggesting that this difference is not due to increased latency variability with age. The old subjects had lower single trial P3-RT correlations and longer elapsed time from P3 peak to the response than did the young subjects. Both groups had greater RTs for outset items ('negative' responses) than for inset items ('positive' responses). For the young subjects P3 latency was also greater for the outset compared to the inset items but the difference was not found for the old subjects. Thus, the relationship between P3 latency and RT is altered in the aged--P3 and RT are less tightly coupled than in the young.  相似文献   
1000.
Nonpenetrating trabeculectomy was performed on 28 aphakic eyes consisting of 18 with chronic open-angle glaucoma and 10 with secondary and/or complicated glaucoma. The canal of Schlemm and the juxtacanalicular trabecular meshwork were excised for a length of 4 mm beneath a 6 mm x 6 mm scleral flap. At one year postoperatively, 72.0% of all patients were controlled, 24% required no antiglaucoma medications. However, 88% of chronic simple glaucoma patients were satisfactorily controlled. The mean follow-up period was 1.4 years. Minimal complications have been encountered to date. Nonpenetrating trabeculectomy may be valuable as an initial procedure in aphakic patients who require glaucoma filtration surgery.  相似文献   
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