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71.
R F Rossi R Ekroth K Jansson M Scallan R J Thompson C Lincoln 《Scandinavian journal of thoracic and cardiovascular surgery》1990,24(1):75-77
The concentration of brain type creatine kinase (CK-BB) was measured in blood from the internal jugular vein in 32 children (less than 1 year old) with congenital heart disease. In transposition of the great arteries the CK-BB levels were significantly higher than in children without cyanosis (10.1 +/- 4.1 vs. 3.0 +/- 0.5 ng/ml). A negative correlation was found for CK-BB concentration and arterial oxygen saturation (r = -0.41, p less than 0.02 for all children and r = -0.62, p less than 0.05 for those with tetralogy of Fallot). It is suggested that the increased CK-BB levels in the blood of cyanotic children reflect chronic cerebral hypoxia, which may explain other reports of reduced psycho-intellectual function in patients with cyanotic heart disease. 相似文献
72.
Recent reports have fueled an interest in the prevalence and significance of metastatic calcium deposition in patients with chronic hyperparathyroidism. Experimental data are limited by the lack of suitable in vivo animal models. We have developed a model of marked hypercalcemia and overproduction of parathyroid hormone using somatic gene transfer. Briefly, the process involves infection of cultured rodent fibroblasts (RAT-1 cells) with a retroviral expression vector that contains the gene encoding human parathyroid hormone. Fibroblasts are grown to confluence on collagen-coated dextran microcarrier beads and are injected into the peritoneal cavities of syngeneic Fisher rats. Human parathyroid hormone production in rat serum is quantified by an immunoradiometric assay for human parathyroid hormone (1-84), which does not recognize rat parathyroid hormone. These rats consistently show production of human hormone within a week. Levels increase progressively, often to 1 ng/ml within 60 days of injection. Serum calcium showed a concomitant rise to an average of 15.5 mg/dl. In this study, 13 rats that had been transplanted with parathyroid hormone-producing fibroblasts were killed 80 days after injection. Examination of the skeleton revealed demineralization and histopathologic sequelae of parathyroid hormone excess with extensive osteoclastic bone resorption. Examination of the hearts revealed calcification in five of 13 hearts. There was no involvement of major coronary arteries or conducting systems, but there was calcification of cardiac myocytes, primarily in subepicardial region. This model may permit an understanding of the mechanisms for sudden cardiac death in severe hypercalcemia. 相似文献
73.
Sarabjit S. Neelam Alvise Bernabei Curtis Freedland Roxanna Thompson Thomas H. Corbett Gordon D. Luk 《Investigational new drugs》1990,8(3):263-268
Summary Unresectable solid tumors in the metastatic stage are quite resistant to current chemotherapy and radiation therapy regimens. Flavone acetic acid (FAA) is a novel antitumor agent which appears to work through a different mechanism than the conventional chemotherapeutic agents. In preclinical studies it has shown effectiveness against a variety of transplantable murine and human tumors and appears to be solid tumor selective. It also has non-overlapping toxicities as compared to conventional agents. We therefore investigated FAA in vitro against human colon cancer cells and explored whether its effectiveness could be enhanced in combination with other agents such as adriamycin (ADR), cis-platinum (CP) and difluoromethyornithine (DFMO) — an inhibitor of polyamine biosynthesis. Addition of FAA for 24 hours in liquid media produced dose dependent growth inhibition. Using soft agar colony assay, growth was inhibited by 58% by 3mM FAA and only 1.4% by 0.375mM FAA. The combination of FAA and cis-platinum produced synergism at the lower doses tested. The combination of FAA and adriamycin produced antagonism at all doses tested and the combination of FAA with DFMO did not produce results significantly different from DFMO alone. We conclude that enhancement of FAA activity can be achieved in combination with conventional antitumor agents, but may be drug and dose specific. 相似文献
74.
Infective conjunctivitis and corneal scarring in three brothers with sex linked hypogammaglobulinaemia (Bruton''s disease). 下载免费PDF全文
T T Hansel D P O''Neill M L Yee J M Gibson R A Thompson 《The British journal of ophthalmology》1990,74(2):118-120
The ocular findings in three brothers with Bruton's disease are reported. All three boys had purulent conjunctivitis, but the two older brothers also developed marked corneal scarring with visual impairment. Haemophilus influenzae was cultured from conjunctival swabs; it was resistant to neomycin but sensitive to chloramphenicol. Tear analysis showed that the three subjects had normal levels of lysozyme but no detectable IgA. 相似文献
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H. William Scott Jr. M.D. Craig R. Sussman M.D. David L. Page M.D. Norman W. Thompson M.D. Milton D. Gross M.D. Ricardo Lloyd M.D. 《World journal of surgery》1986,10(4):646-652
Since the syndrome of primary hyperaldosteronism was described by Jerome Conn in 1955, over 300 patients with this disorder have been identified in the medical centers of Vanderbilt University and the University of Michigan. The most frequent cause of this endocrinopathy has been a solitary adenoma of the adrenal cortex (72%); bilateral adrenocortical hyperplasia has been the cause of primary hyperaldosteronism in 27% of cases; less frequently, the cause has been multiple and/or bilateral adenomas (1%). During the last 4 years in these 2 medical centers, we have encountered 3 patients who have had biochemically proven primary hyperaldosteronism due to adrenocortical carcinoma. Each of these unusual cases is summarized with review of the recent literature.
Presented at the International Association of Endocrine Surgeons in Paris, September 1985. 相似文献
Resumen Desde la descripción del síndrome de hiperaldosteronismo primario por Jeremo Conn en 1955, más de 300 pacientes con esta entidad han sido identificados en nuestros 2 centros médicos, la Universidad de Vanderbilt (Nashville) y la Universidad de Michigan (Ann Arbor). La causa más frecuente de esta endocrinopatía ha sido el adenoma solitario de la corteza suprarrenal (72%); la hiperplasia adrenocortical bilateral ha sido la causa del hiperaldosteronismo primario en 27% de los casos; con menor frecuencia se han presentado los adenomas multiples y/o bilaterales (1%). En los 4 últimos años hemos encontrado 3 pacientes con hiperaldosteronismo primario comprobado bioquímicamente producido por carcinoma adrenocortical. Se presenta cada uno de estos casos poco usuales junto con una revisión de la literatura reciente.
Résumé Depuis que le syndrome d'hyperaldostéronisme primitif a été décrit par Jerôme Conn en 1955 plus de 300 sujets qui en étaient victimes ont été identifiés à la Vanderbilt University de Nashville et à l'University of Michigan de Ann Arbor. La cause la plus fréquente de cette endocrinopathie répond à un adénome solitaire de la cortico-surrénale (72%) alors que l'hyperplasie corticale des 2 surrénales est plus rarement à son origine (27%), les adénomes multiples et/ou bilatéraux étant rarissimes (1%). Au cours des 4 dernières années 3 cas d'hyperaldosteronisme dû à un cancer de la cortico-surrénale ont été observés dans les 2 centres. Chacun de ces cas exceptionnels est exposé cependant que la littérature récente concernant l'hyperalderosteronisme est analysée.
Presented at the International Association of Endocrine Surgeons in Paris, September 1985. 相似文献
77.
B W Brown E N Atkinson J R Thompson E D Montague 《Journal of the National Cancer Institute》1987,78(3):425-435
The degree of concordance of growth rates of primary tumors with corresponding recurrences was investigated by using data from 184 patients with breast cancer with measurable recurrences. For conduction of this examination, the detection processes of both the primary tumor and the recurrence were explored. The probability of detection of a recurrence per unit time was found to be nearly proportional to the tumor's diameter. Approximately 60,000 cells initiated the recurrence, and the distribution of doubling times of the recurrences was exponential, with a mean of 2.1 months. The probability of detection of the primary tumor per unit time was approximately proportional to its volume. The distribution of doubling times of primary tumors was nearly exponential; from other evidence, we inferred that the mean doubling time was also close to 2.1 months. Several techniques to measure growth rate agreement between the primary and recurrent tumors within individuals were developed, and all of them yielded the result that the growth rates are nearly unrelated. 相似文献
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Actin cytoskeletal polymerization is associated with a pro-proliferative, pro-survival state. We hypothesized that the actin polymerization of wound cells is increased in the presence of wound matrix attachment and is decreased after disruption of this attachment. Musculocutaneous flap and wound splinting models were used to investigate the effect of wound matrix attachment on the actin cytoskeleton. Disruption of wound matrix attachment was accomplished by incision of the wound matrix/dermis interface (wound matrix release) and/or desplinting. Polymerized actin was assayed with phalloidin labeling of wound specimens 24 hours after disruption of attachment and a method to quantify the content and organization of polymerized actin in granulation tissue was used. Disruption of wound matrix attachment decreased the content of polymerized actin, the actin staining intensity, and the actin fiber organization in the granulation tissue of both the flap and splint models. Disruption of wound matrix attachment decreased actin polymerization and fiber organization in the granulation tissue. Our data support the concept that the state of wound matrix attachment regulates the actin cytoskeleton of wound cells. 相似文献