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621.
622.
Five cases of the Hirschsprung's disease-congenital central hypoventilation syndrome (CCHS) association are presented and 41 other published cases reviewed. These children have a distinct pattern of associated features, an equal sex incidence, and a characteristic spectrum of disease severity which suggests that the condition is genetically distinct from other cases of Hirschsprung's disease. While approximately 1.5% of Hirschsprung's disease patients, and 10% of those with total colonic aganglionosis, will have CCHS, up to 50% of CCHS patients will have Hirschsprung's disease. Approximately 20% of CCHS/Hirschsprung patients will also have neuroblastoma or ganglioneuroma, usually multiple. Abnormalities of the eye and autonomic nervous system are also common. The ventilatory abnormality is usually evident on the first day of life. The aganglionosis is also severe, with more than half (59%) of the patients having aganglionosis extending into the small bowel.  相似文献   
623.
624.
Homozygous and compound heterozygous mutations at the Werner syndrome locus   总被引:2,自引:0,他引:2  
The Werner syndrome (WS) is a rare autosomal recessive progeroid disorder. The Werner syndrome gene (WRN) has recently been identified as a member of the helicase family. Four distinct mutations were previously reported in three Japanese and one Syrian WS pedigrees. The latter mutation was originally described as a 4 bp deletion spanning a spliced junction. It is now shown that this mutation results in a 4 bp deletion at the beginning of an exon. Nine new WRN mutations in 10 additional WS patients, both Japanese and Caucasian, are described. These include three compound heterozygotes (one Japanese and two Caucasian). The new mutations are located all across the coding region.   相似文献   
625.
626.
尼莫地平胃内滞留漂浮型缓释片的研究   总被引:17,自引:0,他引:17  
吴伟  周全  张恒弼  马光大  傅崇东 《药学学报》1997,32(10):786-790
将尼莫地平先制成速释型固体分散体,再压制成胃内滞留漂浮型缓释片(NM-FSRT)。均匀设计法优选处方,并考察处方因素对尼莫地平释放的影响,在人体内对NM-FSRT进行了初步评价。结果表明优选处方于体外漂浮达10h,0.15~6h释放符合零级动力学。HPMC量越大,药物释放越慢,PEG 6000量越大,释放越快。饮食后NM-FSRT于胃内滞留时间约5h,空腹时约3h;对照非漂浮片饭后服滞留时间为3h,空腹2h排空。体内相对生物利用度为391.46%,MRT较普通片延长一倍多。  相似文献   
627.
Anemia is a universal finding in patients undergoing autologous bone marrow transplantation (BMT). Effective therapies to increase the number of autologous red blood cells could result in a lower morbidity and mortality associated with red blood cell transfusions. We examined whether the addition of erythropoietin (Epo) to intensive therapy supported by progenitor cell transplantation and granulocyte colony- stimulating factor (G-CSF) would result in a lower requirement for red blood cell transfusions. Thirty-five patients with lymphoma were randomized to receive Epo versus placebo. Epo (600 U/kg three times per week) or placebo was begun 3 weeks before administration of high-dose therapy. Epo was held during the week of the preparatory regimen, and restarted on the day after BMT. All patients also received G-CSF following BMT. No significant differences were noted between the two groups in terms of patient characteristics at pretreatment or post-BMT evaluation. There were no differences in the total number of red blood cell units transfused (median Epo: 8 v placebo: 6, P = .22) nor the number of platelet transfusions given (median Epo: 12 v placebo 5, P = .14). Engraftment of granulocytes (absolute neutrophil count > or = 500/microL) occurred in a median of 12 days (range, 9 to 33) for the patients receiving Epo and G-CSF, compared with a median of 10 days (range, 8 to 22) for those receiving placebo and G-CSF (P = .70). Likewise, there were no differences in the time to platelet count > or = 20,000/microL without further transfusions with a median of 22 days (range, 15 to 150+) for those receiving Epo and G-CSF compared with a median of 20 days (range, 11 to 54) for those patients receiving placebo and G-CSF (P = .28). The combination of G-CSF and Epo as administered in this study appears to be safe but does not result in an improvement in the total number of red blood cell transfusions or total number of single donor platelet units transfused.  相似文献   
628.
The authors describe differences in behaviour of left ventricular systolic time intervals after isometric exercise between patients with ischemic heart disease and normal control. Isometric exercise consists of tonic hand-grip, which is to be gauged by hand-grip dynamometer for 5 minutes at 30% of the patient's maximum voluntary contraction or for 2-3 minutes at 50%. The parameters referred to are pre-ejection period and left ventricular ejection time index (PEPI, TETI), the PEP/TET ration, heart rate and arterial pressure. The authors conclude that from isometric exercise it is possible to point out the heart failure degree in patients with ischemic heart disease.  相似文献   
629.
Angiographic ablation of parathyroid adenomas with ionic contrast material was performed in 24 patients with persistent hyperparathyroidism who had undergone at least one prior unsuccessful surgical resection; 23 had mediastinal adenomas. The success rate was 83% at 1 month after ablation and 71% at both 5 and 9 years. Ablation was successful in 85% of the patients in whom the catheter could be wedged into the artery feeding the adenoma. Long-term success was achieved in 89% of the patients in whom contrast enhancement persisted in the adenoma on computed tomographic scans obtained 24 hours later. Acute complications were seen only in patients with glands supplied by the inferior or superior thyroid arteries. Long-term complications were limited to permanent hypocalcemia, present in 8% of patients. Even if unsuccessful for ablation, the procedure may provide localization and does not preclude surgical resection. It is recommended for most patients with persistent hyperparathyroidism and mediastinal adenomas, especially adenomas supplied by the internal thoracic artery.  相似文献   
630.
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