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101.
102.
Three-dimensional gel culture systems represent conditions that mimic the differentiated state of mesenchymal cells in vivo. We examined gel contraction, cell growth, and phenotypic modulation of rabbit arterial SMC in three-dimensional gel culture. The gel contraction rate was dependent on the collagen type; that is, the contraction by freshly isolated SMC was faster and more pronounced in type I collagen than in type III collagen. In contrast, the phenotypic modulation of SMC was independent of collagen type. The major portion of cells in both type I and III collagens with growth factors underwent transition from a contractile (G0 phase) to a synthetic phenotype (G1B phase), but this transition was clearly delayed compared with that on collagens. The cells had hardly begun DNA synthesis in either collagen type and failed to proliferate even after 10 days of culture. These results indicate that collagen type is important in gel contraction by vascular SMC, while the organization of collagen fibrils (two-dimensional vs three-dimensional) is more critical in the phenotypic transition and proliferation of these cells. However, the more specific organization of extracellular matrix than the collagen gel culture system may be necessary to maintain the contractile phenotype of SMC. 相似文献
103.
The first isolated case of agenesis of the mastoid antrum, previously only described in association with the congenital syndromes trisomy 13 and mandibulofacial dysostosis, is reported. The loss of this important surgical landmark may result in disorientation and iatrogenic trauma. The surgeon must be aware of its existence, and where it is suspected the middle fossa dura should be exposed and followed posteriorly until the lateral sinus is encountered. 相似文献
104.
HA Israel 《Canadian Metallurgical Quarterly》1997,17(4):355-366
Temporomandibular disorders are a complex group of conditions which are common causes of orofacial pain and are frequently associated with headaches. Because a wide variety of diseases can ultimately cause symptoms that result in dysfunction of the masticatory system, it is important for the clinician to establish an accurate diagnosis and rule out any serious neurologic pathology. Serious extra-articular conditions often can simulate the nonspecific symptoms of a temporomandibular joint disorder. A careful history and clinical examination of the head, neck, and cranial nerves are important in establishing a differential diagnosis. Diagnostic imaging and consultation with specialists in several disciplines are often necessary to establish an accurate diagnosis and develop an appropriate therapeutic regimen. 相似文献
105.
Lizards (Dipsosaurus dorsalis) were placed in a desertlike environment in which the ambient temperature (Ta) at night (1800-0600 h) was 12 degrees C and the day (0600-1800 h) Ta was between 30 and 55 degrees C depending on the location within the chamber. When dead Aeromonas hydrophila (4 X 10(9) organisms) was injected into nine lizards, an elevation in body temperature (Tb) of 2.7 degrees C was observed during the same day. On the day after bacterial injection the lizards' body temperatures averaged 41.6 degrees C, an increase of 4.2 degrees C over their control day Tb. Further investigations on the febrile response of D. dorsalis were conducted at the University of Wisconsin's Biotron, where there exists a simulated desert environment with the light intensity, temperature, and humidity closely parelleling a typical spring day in the southwestern desert of the United States (the natural habitat of Dipsosaurus). In this environment injection of dead bacteria into seven lizards led to an average febrile response of similar magnitude (Tb = 40.5 degrees C) but with a longer latency than that found at the University of Michigan. Injection of 13 lizards with live A. hydrophila (5 X 10(9) organism subcut.) in the simulated desert at Michigan led to a daytime fever averaging 2.3 degrees C (mean Tb = 40.6 degrees C) over a 5-day period. During the 6th and 7th day the lizards' body temperature returned to the normal or afebrile level. Injections of sodium salicylate along with dead A. hydrophila resulted in a dose-dependent attenuation of the febrile response. These results demonstrate that the reptilian febrile response is strikingly similar to avian and mammalian fever and suggest a common origin and perhaps function for the febrile mechanism. 相似文献
106.
107.
A 6-week-old breast-fed infant had obstructive jaundice and hepatomegaly. When a dry-cleaning solvent, tetrachloroethylene, was detected in the mother's milk and blood, breast-feeding was discontinued. Rapid clinical and biochemical improvement followed. The child grew normally and had normal liver function during 2 years of follow-up. 相似文献
108.
109.
This paper describes a study of the physico-chemical and radioimmunological properties of three antialdosterone antisera which permitted practical conclusions to be drawn. By its high degree of specificity, anti-aldo-3-oxime-BSA constitutes the most useful antiserum for the clinical assay of aldosterone. The principal advantage of this antiserum is that it allows both urinary and blood aldosterone radioimmunoassay without the necessity of including a chromatographic step. No problems arise with the blanks. This work also includes the study of two anti-deoxycorticosterone antisera. The aldosterone and deoxycorticosterone values, obtained from normal subjects under various physiological conditions, are in agreement with the values given in the literature. 相似文献
110.