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21.
Chronic arthropathy occurring after augmentation mammaplasty   总被引:1,自引:0,他引:1  
Augmentation mammaplasty has been associated with a broad spectrum of connective-tissue disease, systemic illness and autoimmune phenomena. The three cases reported herein suggest a possible relationship between silicone gel implants for augmentation mammaplasty (with capsular contractures as complicating feature) and the development of chronic arthropathy.  相似文献   
22.
Feasibility of automating the micronucleus assay   总被引:1,自引:0,他引:1  
The results of a feasibility study on the automation of the micronucleus assay in whole blood cultures of human lymphocytes are reported. The assay requires determination of the number of lymphocytes with micronuclei among the proliferating population. Using an in-house-assembled image analysis system, a prototype software package was developed that addressed two problems: micronuclei identification and discrimination of nonproliferating cells from proliferating lymphocytes (the only ones that can give rise to micronuclei). The results of manual verification of automated micronucleus scoring showed that 70% of all digitized micronuclei were extracted from the images and 90% of them were correctly classified and paired with a parent nucleus by an "affinity function". The discrimination between proliferating and nonproliferating cells was carried out by linear discriminant analysis of simple nuclear features extracted from Feulgen-stained cells. Among the Feulgen-stained nuclei that were identified by autoradiography as proliferating or not, 85% were correctly classified by a six-feature discriminant function.  相似文献   
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Boke , Norman H. (U. Oklahoma, Norman.) Endomorphic and ectomorphic characters in Pelecyphora and Encephalocarpus. Amer. Jour. Bot. 46(3) : 197-209. Illus. 1959.—Outstanding ectomorphic characters of Pelecyphora valdeziana include its small size; pectinate, hairy spines; broad, truncate, floral buds; dehiscent, berry-like fruits; and black, tuberculate seeds. The leaves are vestigial, and although the areole meristem originates on the adaxial face of the tubercle primordium, it is soon elevated to the summit by intercalary growth. The first primordium of the single, elliptical series of spines is initiated immediately in front of the rudimentary leaf. Others form in acropetal sequence on either side of the areole meristem. The last ones form across the areole, leaving a meristem, which may be floral or vegetative, on the anterior side. Whether areoles of P. valdeziana can be considered dimorphic is doubtful. However, they approach the type of dimorphism found in Epithelantha. Pelecyphora aselliformis has acuminate floral buds; dry, papery fruits; and brown, curved, reticulate seeds. The leaves are reduced almost to extinction. The areole meristem becomes separated into spiniferous and axial portions early in ontogeny, but the 2 parts remain connected by a band of trichomes, which probably represents a vestigial groove. The axial meristem may be reproductive or vegetative. The sequence of spine initiation in P. aselliformis is unusual in that it begins at the anterior side of the spiniferous meristem and proceeds toward the posterior side. Areoles in this species are clearly dimorphic, much as in the mammillarias, but the vestigial groove is reminiscent of Coryphantha and related genera. Although adult specimens of Encephalocarpus strobiliformis bear scale-like tubercles, which are very different from the laterally compressed tubercles of P. aselliformis, their flowers, fruits, and seeds are almost identical. The two species share the same type of areole dimorphism, including the vestigial groove. Tubercles on seedlings and young branches of E. strobiliformis are prismatic rather than scale-like. Since they tend to be laterally compressed at the summit and bear elliptical areoles with many more spines than the adult, they resemble seedling tubercles of P. aselliformis. Tubercles on adult specimens likewise resemble each other in the structure of the epidermis and hypodermis. It does not seem possible that P. valdeziana can be retained in the genus Pelecyphora. If seed structure has any systematic value, the species belongs in or near the genus Thelocactus, to which it was assigned by Bravo. Pelecyphora aselliformis and Encephalocarpus strobiliformis, on the other hand, share so many important characters that they could well be considered cogeneric. Both seed structure and the rudimentary grooves on the tubercles suggest that their affinities may lie with certain coryphanthas or mammillarias rather than with Ariocarpus and Epithelantha.  相似文献   
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Summary 1. On the seaward face of Port Erin breakwater large algae do not occur on the lowest three metres. Here the density ofEchinus esculentus is high.2. Over a three year period allEchinus were removed from a 10 m wide strip at about monthly intervals. The total number of individuals removed approached 3000.3. One year after initial clearance the mean density ofLaminaria hyperborea sporelings on the strip was 22.7/m2 and 5.1/m2 to one side of it. By the winter these had almost disappeared outside the strip and in the succeeding years second and third year plants were found only on the strip or close to its edge. Other algae were similarly affected.4. It is concluded that the lower limit ofL. hyperborea is determined at least in part by the grazing pressure ofEchinus and that the urchins exercise some control over the numbers of other algae.
Algenkolonisation im untergetauchten Gezeitenbereich nach Entfernung vonEchinus
Kurzfassung An der Sesseite des Port Erin Wellenbrecherdammes kommen keine größeren Algen im Bereich der unteren 3 m vor. Hier herrscht eine große Besiedlungsdichte des SeeigelsEchinus esculentus (3,6 Individuen pro m2). Über eine Zeitspanne von 3 Jahren wurden nun sämtlicheE. esculentus von einem 10 m breiten und 12 m langen Felsstreifen allmonatlich entfernt; insgesamt wurden dabei etwa 3000 Individuen abgesammelt. Ein Jahr nach Beginn des Absammelns betrug die mittlere Siedlungsdichte der jungenLaminaria hyperborea auf dem von Seeigeln freigehaltenen Felsstreifen 22,7/m2. In den folgenden Jahren wurden zwei- und dreijährigeL. hyperborea nur auf diesem Felsstreifen oder in der Nähe seiner Begrenzungen gefunden. Andere Algenarten reagierten in ähnlicher Weise. Aus den Befunden wird gefolgert, daß die untere Verbreitungsgrenze vonL. hyperborea zumindest zum Teil durch Seeigelfraß bestimmt wird, und daßE. esculentus die Siedlungsdichte der anderen Algenarten beeinflußt.
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Summary The results of this study indicated that antigens prepared from the three morphological phases ofCoccidioides immitis differed in their complement fixing activity with anti-Histoplasma capsulatum pooled serum. Spherule antigens were serologically less active in tests with the anti-H. capsulatum pooled serum than antigens prepared from arthrospores and from mycelium.Antigenic determinants which are common toC. immitis andH. capsulatum appeared to be located on the intact arthrospore cellular surface but not on the surface of spherule cells.Part of a dissertation submitted to the Graduate School of Duke University in partial fulfillment of requirements for the Ph. D. degree.This work was supported by contract with the Department of the Army, Fort Detrick, Frederick, Maryland.In conducting the research reported herein, the investigators adhered to Guide for Laboratory Animal Facilities and Care established by the Committee on the Guide for Laboratory Animal Facilities and Care of the Institute of Laboratory Animal Resources, NAS-NRC.  相似文献   
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It has been reported that vitamin K deficiency in the rat markedly increases the 1,25-dihydroxyvitamin D3 receptor (VDR) binding to DNA and that vitamin K-dependent gamma-carboxylation of endogenous substrates of the intestinal and renal cytosol, also containing VDR, sharply reduced that binding (Sergeev, I.N., and Spirichev, V.B. (1989) Nutr. Res. 9, 725-733). In the present study we have evaluated vitamin K-dependent 14CO2 incorporation to VDR quantitated by immunoprecipitation with anti-VDR monoclonal antibodies. The results obtained strongly suggest that VDR in vitro can undergo gamma-carboxylation in the presence of vitamin K1 and that 15-25% of Glu residues in the VDR are carboxylated in vivo. Taking into account our earlier findings, it is likely that the VDR gamma-carboxylation modulates its binding to DNA.  相似文献   
30.
The effects of pH titration on the EPR spectra of imidazolidine nitroxides located at the surface of mixed bilayers composed of dimyristoylphosphatidylglycerol (DMPG) and dimyristoylphosphatidylcholine (DMPC), and at the surface of the protein, human serum albumin (HSA), have been investigated. It is found that the shift in pKa of the amino group of the imidazolidine radical from its value of 4.6 in water depends both on the interfacial polarity (delta pKapol) and on the electrostatic surface potential (delta pKael) when it is positioned at the bilayer/water interface by an anchoring hydrocarbon tail. The polarity shift is determined to be: delta pKapol = -1.3 units at the surface of DMPC bilayers at 17 degrees C, corresponding to an effective interfacial dielectric constant of epsilon approximately 37, and depends on the temperature with a coefficient of d delta pKapol/dT approximately -0.01 per degree. The electrostatic shift at the surface of DMPG bilayers is delta pKael = +1.6 units in 0.1 M KCl, which corresponds to an electrostatic surface potential of -95 mV. This electrostatic shift depends strongly both on ionic strength and on the fraction of charged lipid in the DMPC/DMPG mixtures, in a manner that agrees with the predictions of electrostatic double-layer theory. It is found that the shift in pKa of an imidazolidine radical covalently bound at the surface of HSA is determined mainly by the surface electrostatics (delta pKapol approximately 0) and corresponds to an electrostatic potential of +33 mV in 0.01 M KCl at a pH below the isoelectric point of the protein.  相似文献   
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