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941.
An excess of structural defects occurs in monozygotic twins compared in dizygotic twins or singletons. The excess is composed of three categories of defects. The first includes defects which are part of the MZ twinning, such as conjoined twins and some amorphous twins. In addition, all early embryonic malformations and malformation complexes such as sirenomelia mc. holoprosencephaly mc. and anencephaly mc are increased in MZ twins. The reason for this association is considered to be the common etiology for both the MZ twinning and the early malformation problem. MZ twins provide an excellent model for appreciating the spectra of particular malformation complexes, since the twins often have different gradations in severity of the same type of structural defect. The finding of both discordant and concordant MZ twins with Goldenhar, de Lange, and Rubinstein-Taybi syndromes suggests that these "syndromes" might be early malformation complexes. The other two categories are considered secondary to the MZ twinning process. The most unique category results from any vascular interchange between the MZ twins. Depending on their nature, vascular connections may give rise to reverse flow with acardiac status in one twin during early development, or to vascular disruptions from a deceased co-twin with intravascular coagulation causing embolization in the surviving co-twin. The latter defects may include microcephaly, porencephalic cysts, hydranencephaly, intestinal atresia, aplasia cutis, and limb amputation. Unequal growth may occur as a result of artery to vein placental anastomoses. The final category is deformations due to crowding in utero during late gestation. These do not differ from those in DZ twins. 相似文献
942.
Five patients with polypoid esophageal sarcoma are reported. All had dysphagia similar to that occurring in epithelial carcinoma of the esophagus. The clinical diagnosis of sarcoma was suspected when barium swallow showed a large polypoid lesion. Biopsy was often inconclusive concerning the nature of the lesion except to identify it as a neoplastic process. In spite of their large size, the tumors remained superficial within the esophageal wall. Nodal or distant organ metastasis was absent in 4 of the 5 patients. The histology of these tumors suggests that so-called carcinosarcoma is an epithelial carcinoma of the esophagus with varying amounts of spindle cell features and should be considered separately from sarcoma arising from mesenchymal tissue. Unlike carcinoma, esophageal sarcoma has a favorable prognosis following radical resection, and recent advances in esophageal surgery have decreased the mortality and morbidity of esophagectomy. 相似文献
943.
Subclavian vein catheterization in the infant 总被引:1,自引:0,他引:1
944.
945.
Parental overprotection and asthma 总被引:1,自引:0,他引:1
Using a reliable and valid measure of parental overprotection, the oft-put clinical view that asthmatics' parents are overprotective was confirmed, with asthmatics scoring both their motors and their fathers as similarly overprotective in a controlled study. The study was designed to determine if parental overprotection is likely to be an antecedent to, or a consequence of asthma in a child. Results suggested that parental overprotection is a consequence of asthma in a child, but this was more clearly demonstrated for the fathers than for the mothers. The authors conclude that parental overprotection associated with asthma is likely to reflect an adaptational response by parents to a child with a chronic, unpredictable illness arousing high levels of anxiety in parents. 相似文献
946.
O Kahn 《American heart journal》1974,88(5):656-663
This report deals with 53 patients treated with prosthetic cardiac pacers solely by one “interested” physician at the community level over a period of 5 years and 2 months.The 5-year mortality rate was 41.5 per cent; (15.1 per cent cardiogenic and 26.4 per cent noncardiogenic). A complication rate of 28.2 per cent with one fatality (1.9 per cent) due to a faulty pacemaker was experienced. These results compare favorably with a similar medically treated group, who had an immediate in-hospital cardiogenic mortality of 35 per cent. Contrary to other reports, premature battery depletion was not found in this series.This community study compares favorably to several university studies, who report a complication rate of 63 per cent, a mortality rate of 6.7 per cent versus 28.2 and 1.9 per cent, respectively, as experienced in this group. This study indicates that community standards are equal to or superior to university standards in this particular mode of therapy. 相似文献
947.
Coxsackie viruses belong to a large group of viruses called picornaviruses. This group of viruses contains a ribonucleic acid (RNA) core; the nucleocapsid has cubic symmetry; the virion has no envelope; and infectivity is resistant to lipid solvents such as ether and chloroform. Coxsackie viruses are divided into two groups based on their pathogenicity in suckling mice; group A contains 24 types and group B 6 types. Numerous reports of Coxsackie virus B outbreaks involving adults have established the considerable importance of these viruses as a cause of acute pericarditis and myocarditis. The diagnosis is based on viral isolation and serologic techniques. Coxsackie virus heart disease usually is observed during epidemics Involving several diseases including Bornholm disease or cardlorespiratory tract syndromes. The treatment of acute myopericarditis is mainly supportive. 相似文献
948.
949.
Kevin Turley Gus J. Vlahakes Michael R. Harrison Louis Messina Frank Hanley Paul N. Uhlig Paul A. Ebert 《The Annals of thoracic surgery》1982,34(4):422-426
We have developed fetal lamb models of congenital cardiothoracic lesions that have been allowed to progress through birth for physiological study. Simulated lesions, simulated repairs, actual lesions, and actual repairs have been performed in this model.Sixty-two fetal lambs comprised the study group, including 48 in which models were created and 14 controls. Models included pulmonary stenosis, aortic stenosis, and diaphragmatic hernia. Gestational age ranged from 90 to 120 days (0.6 of normal gestation). In each pregnant ewe, laparotomy and hysterotomy were performed under general anesthesia, with care taken to avoid placental vessels. The foreleg was exposed, the appropriate anterior chest wall was isolated, and a thoracotomy was done. Thoracic or cardiac procedures then were performed under controlled transplacental anesthesia and perfusion. Following completion of the procedure, the fetal thoracotomy was closed, sterile antibiotic solution was placed in the amniotic sac, and the hysterotomy and laparotomy were closed. Subsequently the fetus either was allowed to progress to birth and infant study or underwent subsequent intrauterine repair and then was allowed to progress to birth and neonatal study.This fetal lamb model provides reproducible anatomical and pathophysiological lesions to facilitate the development of techniques for repair of such lesions in early infancy. Further, it offers the potential for developing methods of intrauterine cardiothoracic surgical repair. 相似文献
950.
基于"全人发展"理念下的独立学院医学生培养模式探究 总被引:1,自引:1,他引:0
近年来,独立学院迅速崛起,成为扩充本科优质教育资源的战略选择。独立学院起步一般都是依托一个母体大学而设立。积极探索符合自身培养学生的目标,又适应独立学院学生特点的培养模式,形成具有鲜明的办学特色,是独立学院能够长期可持续发展的重中之重。树立“全人发展”的新理念,对独立学院医学生的培养具有十分重要现实意义。 相似文献