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101.
Investigations into the effects of prior silicone exposure on subsequent capsule formation around silicone implants assume particular relevance in light of the exponential increase in the medical application of polymers such as silicone. The inert nature of silicone has been in question with regard to its effects on the immune system, specifically whether or not it may act as a hapten or antigen. The present study analyzes the effects of prior silicone exposure on subsequent capsule formation, histological consistency, and pressures when an animal is reexposed to a silicone implant. Twelve female Lewis rats (body weight 250 g) were randomly divided into two groups. Group 1 (n = 6) rats were subcutaneously injected with 2.5 ml of Freund's Complete Adjuvant, Group 2 (n = 6) rats were injected with an equal volume of adjuvant sonicated with silicone gel. At 4 weeks a gel-filled silicone implant was placed subcutaneously in each animal. Capsule pressures were obtained at 4 months and the capsules from 3 rats from Group 2 were excised and examined microscopically. Pressures were measured again at 8 months and all remaining capsules were excised and examined. No statistically significant differences were noted when comparing two profiles over time between silicone-exposed and nonexposed animals in regard to capsule thickness or capsule pressure. However, capsule pressures were significantly lower at 8 months than at 4 months in both groups (p less than 0.034). In this model, significant reductions in capsule pressure were noted in both groups over time, but prior exposure to silicone did not appear to alter capsule histology, thickness, or pressure.  相似文献   
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This paper reports the composition of a new reference allelic ladder mixture for use with a multiplex DNA profiling system consisting of six short tandem repeat loci. The loci included in this mixture are HUMTH01, D21S11, D18S51, D8S1179, HUMVWAF31/A, HUMFIBRA/FGA and an amelogenin sex test. Sequence analysis of individual ladder alleles was carried out and allelic designations made in accordance with the recommendations of the International Society of Forensic Haemogenetics (1992; 1994). A series of rare alleles which increase the range of alleles previously reported were identified. By including some of the rare alleles into the ladder marker system, we have significantly improved the ability to identify new alleles in unknown samples. Received: 12 August 1997 / Received in revised form: 7 November 1997  相似文献   
105.
Although the association between asbestos exposure and malignant mesothelioma is indisputable, controversy continues regarding the relative contribution of the various types of asbestos fibers to the development of mesothelioma. We examined the types of asbestos fibers recovered from lung parenchyma in more than 90 cases of malignant mesothelioma from the United States, using an analytical scanning electron microscope. Almost half of the patients were former asbestos insulators or shipyard workers. The fibers were recovered from lung tissues obtained at autopsy or surgical resection by means of a sodium hypochlorite digestion procedure. Amosite absestos was identified in 81% of the cases and accounted for 58% of all fibers 5 μm or greater in length. Tremolite/actinolite/anthophyllite were identified in 55% of the cases and accounted for 10% of all fiber types. Chrysotile was identified in 21% of the cases and accounted for 3% of fibers exceeding 5 μm in length. Crocidolite was found in 16% of the cases and accounted for 3% of fibers exceeding 5 μm in length. Nonasbestos mineral fibers (commonly found in the lungs of the general population) were observed in 71% of the cases and accounted for 25% of all fibers 5 μm or greater in length. The findings in this study are at odds with the assertion that crocidolite asbestos is responsible for most mesotheliomas in the United States. © 1993 Wiley-Liss, Inc.  相似文献   
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Genesis of papillar pit. Microscopy study in a newborn infant   总被引:1,自引:0,他引:1  
The rare microscopic picture of a pit of the optic disk is described. The recess extended from the physiological cup of the optic disk to the former cleft of the optic stalk at the point of entry of the ophthalmic artery. There was no disk coloboma. This result is in good agreement with von Szily's paper on the genesis of crater-like holes in the optic disk as a residue of the cavity of the primordial epithelial papilla. In this case there was no communication of the vitreous cavity with a subretinal space, which is suspected of being the cause of the frequent concomitant serous detachment of the macula.  相似文献   
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Care of the newborn diagnosed with a congenital malignancy is a challenge for the neonatal intensive-care unit nurse. Malignancies found in infants differ from those found in older children. Nursing care of the neonate suspected or diagnosed with a congenital malignancy includes standard practices and problem identification as well as interventions unique to the patient with cancer. This article reviews the incidence, diagnosis, treatment, and nursing management of neoplasms diagnosed in neonates.  相似文献   
110.
Zusammenfassung Im Jahr 1988 wurde erstmals von der m?glichen Wirksamkeit der Valproins?ure in der Migr?neprophylaxe berichtet. Seit 1992 sind insgesamt 359 Patienten in 5 Doppelblindstudien untersucht. In allen Studien ergab sich eine signifikant überlegene Wirksamkeit im Vergleich zu Placebo, eine Studie belegt einen gleichen Effekt wie Propranolol. Es fehlen noch Wirksamkeitsanalysen, die sich am Plasmaspiegel orientieren. Die Nebenwirkungen entsprechen denen aus der Epilepsietherapie, scheinen aber im Vergleich zu Propranolol etwas h?her zu liegen. International und nach den Empfehlungen der Deutschen Migr?ne- und Kopfschmerzgesellschaft gilt Valproins?ure mittlerweile als etabliertes Mittel der zweiten Wahl.   相似文献   
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