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231.
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233.
Treatment of the dorsal epidermis of SENCAR mice with 12-O-tetradecanoylphorbol-13-acetate (TPA) induced a time- and dose-dependent stimulation of interleukin-1 alpha (IL-1 alpha) gene expression. Levels of IL-1 alpha mRNA were elevated as early as 15 min and peaked at 3-4 h after a single application of TPA (2 micrograms or 10 micrograms). IL-1 alpha gene expression increased in epidermal tissue isolated from SENCAR mice at 1, 3, 6, 10, 16, and 22 wk after a single treatment with 10 nmol 7,12-dimethylbenz[a]anthracene (DMBA) and subsequent twice-weekly application of 2 micrograms TPA. IL-1 alpha-immunoreactive protein was specifically localized within suprabasal keratinocytes in cutaneous tissue isolated from mice treated with DMBA-TPA for 1-22 wk and in nonproliferating cells located within papilloma tissue isolated from SENCAR mice at 22 wk after initiation and promotion. Basal cells within hyperplastic epidermis did not produce IL-1 alpha-immunoreactive protein. DMBA treatment alone did not induce IL-1 alpha gene expression. Injection of IL-1 alpha-specific antibodies (50 micrograms) into SENCAR mice via the tail vein 2 h before treatment with TPA (2 micrograms or 10 micrograms) significantly (P < 0.05) inhibited the skin thickening usually observed 24 h after treatment with TPA. Autoradiography studies showed that injection of anti-IL-1 alpha antibodies inhibited incorporation of [methyl-3H]thymidine by keratinocytes within the epidermis and by cells within hair follicles. It also inhibited neutrophil infiltration into the dermis, which usually results from topical application of TPA. These data suggest that IL-1 alpha is a pivotal cytokine produced by specific subpopulations of epidermal keratinocytes and that IL-1 alpha primarily regulates the epidermal proliferative response of a distinctly separate population of keratinocytes after topical exposure of murine epidermis to TPA and secondarily modulates neutrophil migration into the dermis. Consequently, manipulation of IL-1 alpha may be a way to attenuate or abrogate the cutaneous response to TPA by altering keratinocyte proliferation, the resultant hyperplasia, and a portion of the inflammatory response characterized by dermal infiltration of neutrophils.  相似文献   
234.
We have established a method for measuring L-dopa in plasma and urine, including the metabolites dopamine and L-dopac, using separation by ion-pair reversed-phase HPLC and quantification with an electrochemical detector. The assay was applied to the therapeutic monitoring of elderly patients with established Parkinson disease being treated with L-dopa plus a dopa decarboxylase inhibitor. Plasma L-dopa was evaluated in relation to dosage and postdose sampling time in 71 outpatients with Parkinson disease. L-Dopa concentrations were greatest in the patients taking the highest dosages prescribed and decreased significantly with increasing time after postdose sampling. Comparison of plasma L-dopa concentrations with a published therapeutic range established by intravenous administration of L-dopa was helpful in assessing the suitability of each patient's drug dosage, assessing patients' compliance, and avoiding overdosage but was not useful in the overall clinical assessment of progression of disease or of the long-term therapeutic response. Urine measurements confirmed the plasma concentrations but showed no further advantage. The recommended time for sample collection is between 1.5 and 3 h after the first morning dose. Plasma is the preferred matrix but if blood sampling is difficult, particularly from elderly/infirm individuals, an untimed urine collection could be used.  相似文献   
235.
As an alternative to the gauze often used on scalp incisions, we prepared a pad made of non-woven sheets, coated with adhesive on one side. Unlike conventional gauze, the pad did not slip away from the incision line or become entangled with the scalp clips, thus demonstrating its high usefulness for this purpose.  相似文献   
236.
BACKGROUND: Controversy exists as to the risk for postoperative apnea in former preterm infants. The conclusions of published studies are limited by the small number of patients. METHODS: The original data from eight prospective studies were subject to a combined analysis. Only patients having inguinal herniorrhaphy under general anesthesia were included; patients receiving caffeine, regional anesthesia, or undergoing other surgical procedures were excluded. A uniform definition for apnea was used for all patients. Eleven risk factors were examined: gestational age, postconceptual age, birth weight, history of respiratory distress syndrome, bronchopulmonary dysplasia, neonatal apnea, necrotizing enterocolitis, ongoing apnea, anemia, and use of opioids or nondepolarizing muscle relaxants. RESULTS: Two hundred fifty-five of 384 patients from eight studies at four institutions fulfilled study criteria. There was significant variation in apnea rates and the location of apnea (recovery room and postrecovery room) between institutions (P < 0.001). There was considerable variation in the duration and type of monitoring, definitions of apnea, and availability of historical information. The incidence of detected apnea was greater when continuous recording devices were used compared to standard impedance pneumography with alarms or nursing observations. Despite these limitations, it was determined that: (1) apnea was strongly and inversely related to both gestational age (P = 0.0005) and postconceptual age (P < 0.0001); (2) an associated risk factor was continuing apnea at home; (3) small-for-gestational-age infants seemed to be somewhat protected from apnea compared to appropriate- and large-for-gestational-age infants; (4) anemia was a significant risk factor, particularly for patients > 43 weeks' postconceptual age; (5) a relationship to apnea with history of necrotizing enterocolitis, neonatal apnea, respiratory distress syndrome, bronchopulmonary dysplasia, or operative use of opioids and/or muscle relaxants could not be demonstrated. CONCLUSIONS: The analysis suggests that, if it is assumed that the statistical models used are equally valid over the full range of ages considered and that the average rate of apnea reported across the studies analyzed is accurate and representative of actual rates in all institutions, the probability of apnea in nonanemic infants free of recovery-room apnea is not less than 5%, with 95% statistical confidence until postconceptual age was 48 weeks with gestational age 35 weeks. This risk is not less than 1%, with 95% statistical confidence, for that same subset of infants, until postconceptual age was 56 weeks with gestational age 32 weeks or postconceptual age was 54 weeks and gestational age 35 weeks. Older infants with apnea in the recovery room or anemia also should be admitted and monitored. The data do not allow prediction with confidence up to what age this precaution should continue to be taken for infants with anemia. The data were insufficient to allow recommendations regarding how long infants should be observed in recovery. There is additional uncertainty in the results due to the dramatically different rates of detected apnea in different institutions, which appear to be related to the use of different monitoring devices. Given the limitations of this combined analysis, each physician and institution must decide what is an acceptable risk for postoperative apnea.  相似文献   
237.
The aim of this study was to examine the effect of the FecBB fecundity gene on plasma concentrations and pituitary content of growth hormone (GH) in sheep. No differences were found between homozygous carriers (BB) and non carriers (++) of the FecBB gene with regard to pituitary GH contents in both ovariectomized and intact ewes. However, ovariectomized ewes had higher levels of pituitary GH than intact ewes (P < 0.01). There were no differences between FecBB genotypes with respect to plasma concentrations of GH in 6-year-old ovariectomized ewes bled every 10 min for 12 h or in ram lambs bled weekly during their first year of life. GH levels in the rams decreased until week 27, increased to a peak at week 31 then decreased before increasing again at week 43. Mean plasma GH concentrations in the ewe lambs bled weekly for a year decreased until week 19 then remained at approximately this level for the remainder of the year. Mean GH plasma concentrations in the ram lambs were higher than in the ewe lambs (P < 0.001). Ewe lambs that were homozygous for the FecBB gene had lower body weights (P < 0.05) and had higher levels of GH (P < 0.01) than non carrier ewe lambs during their first year. Before the average age of first behavioural oestrus (36 weeks) GH levels in the ewe lambs were negatively correlated with body weights (r = -0.69, P < 0.001, n = 22). When body weight was included as a covariate in analysis of variance the genotype difference in ewe lamb plasma GH concentrations was no longer significant.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
238.
Chondrocytes are imbedded in an avascular, highly charged extracellular matrix which could form a barrier to the transfer of dietary essential fatty acids (EFA) to chondrocytes. A study was designed to assess the composition of immature and mature joint cartilage with respect to essential and nonessential fatty acids relevant to EFA deficiency. Cartilage and muscle samples were obtained from human fetus, infant and adult cadavers, and from fetal and mature sheep. Lipid extracts were prepared and the fatty acid composition determined. In human and sheep joint cartilage, linoleic acid (LA; 18:2n-6) content was lower, and n-9 eicosatrienoic acid (ETrA; 20:3n-9) and arachidonic acid (AA; 20:4n-6) were higher in fetuses compared to mature subjects. An intermediate pattern was seen in infant cartilage. n-3 Fatty acids tended to be higher in fetal than in mature cartilage in humans and in sheep. In human muscle (and in other noncartilaginous comparison tissues), similar differences between fetuses and adults were seen in LA and AA, but not in ETrA. In fetal sheep muscle, very low LA, reduced AA and raised ETrA levels compared to mature sheep muscle were seen. However, although the pattern is characteristic of EFA deficiency, the abundance of n-6 EFA in liver and spleen of human fetuses and of n-3 EFA in liver and spleen of fetal sheep suggests that placental transfer of EFA is not likely to be limiting. During fetal development, the metabolism of fatty acids is distinctive and differs between the species. ETrA appears to be a readily measurable component of some tissues at certain stages of development when its presence in tissues does not indicate EFA deficiency.  相似文献   
239.
Mechanical restraints are commonly used to reduce the risks associated with severe self-injurious behavior (SIB), but may result in movement restriction and adverse side effects (e.g., bone demineralization). Restraint fading may provide a method for decreasing SIB while increasing movement and reducing these side effects. In the current investigation, rigid arm sleeves and restraint fading (gradually reducing the rigidity of the sleeves) were used with 3 clients who engaged in hand-to-head SIB. Restraints and fading reduced the hand-to-head SIB of all clients. However, for 1 client, the addition of a water mist procedure further reduced SIB to near-zero levels. For a 2nd client, another form of SIB developed that was not prevented by the rigid sleeves. For a 3rd client, a topography of SIB that was not physically prevented by the rigid sleeves was also reduced when restraints and fading were introduced.  相似文献   
240.
Morphological and histochemical skin properties were studied in male rats in single and successive peroral injections of Zinc sulphate and vitamin A. Long term (25 d) peroral administration of vitamin A 2 mg/100 g in dose was shown to cause hypozincaemia. Zinc sulphate and vitamin A are capable of influencing proliferation and protein metabolism of epidermal cells and number of lymphocytes and mast cells in dermis. With the aim of the drugs named thickness of epidermis, ratio of its layers thickness as well as the rate of protein synthesis in germinal layer of epidermis can be changed purposefully. These parameters depend both on the drug injection technique (single, separated or successive injections) and time periods. Perspective of obtaining a complexed biocoordinative compound on the base of vitamin A and microtrace element of Zinc is discussed.  相似文献   
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