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71.
The cutaneous lymphocyte-associated antigen (CLA) has been proposed as a homing receptor for the selective migration of memory T cells into the skin. To investigate the effect of group A streptococci (GAS) on the migration of T cells in psoriasis, CLA expression was assessed by double-staining for CD3 and the HECA-452 epitope on peripheral blood T cells from 13 patients with psoriasis, 10 patients with other inflammatory skin diseases and 12 normal controls before and after 7 days culture with a GAS sonicate, Candida albicans (control antigen) or medium. In addition, CLA+, and CLA-, CD3+ CD45RO+ subsets were isolated from individuals in each group and V beta 2 expression and proliferation to GAS studied. Mean CLA expression by freshly isolated T cells was almost identical in the three groups. After culture with GAS, T cells from the psoriatic patients and control showed a significant increase in mean percentage CLA+ expression compared to medium (P < 0.002, P < 0.05, respectively). This induction was inhibited by the addition of anti-IL-12 antibody. However, in psoriatic patients, but not in controls, the GAS-induced increase was significantly greater than that of C. albicans (P < 0.002) and was accompanied by a decrease in T cells positive for the peripheral lymph node homing receptor, L-selectin (P < 0.05). The percentage of V beta 2+ T cells was markedly higher in the CLA+ than in the CLA- T-cell subset in psoriatic patients (P < 0.01) and controls; both subsets proliferated to GAS, in each group. These findings suggest a differential modulation of specific tissue homing receptors on T cells by GAS in psoriasis. 相似文献
72.
Fortification of salt with iron has been suggested as a practical method of iron supplementation. In an effort to identify a suitable method for fortifying salt with iron two approaches were investigated. In one the possibility of fortifying salt with ferrous sulfate and a stabilizing agent was tried. Of the several stabilizing agents studied orthophosphoric acid was found to be the most promising one. Salt fortified with ferrous sulfate and orthophosphoric acid was found to keep well on storage without color development. Bioavailability of iron from this fortified salt, although satisfactory at the beginning, deteriorated on storage. An alternative approach in which salt was fortified with ferric orthophosphate, a stable iron compound and an absorption promoter like sodium acid sulfate was found to be more satisfactory. Salt fortified with ferric orthophosphate (3,500 ppm) and sodium acid sulfate (5,000 ppm) kept well without any color development for several months. The bioavailability of iron from this formula was comparable to that from ferrous sulfate and bioavailability did not decrease even after storage for 4-5 months. This fortified salt was also acceptable. This formula offers a practical solution to fortification of salt with iron. 相似文献
73.
Secretory response of the epididymis to exogenously administered testosterone, estrogen and progesterone was investigated using the levels of sialic acid and glycerylphosphorylcholine as indices. Testosterone was found to be most potent in stimulating the (GPC) secretory function of the organ. An enigmatic finding of the present study was that while estrogen showed the ability to stimulate both sialic acid and GPC levels, progesterone exerted its influence only on sialic acid. Studies on the accessory genital organs (weight of seminal vesicles and ventral prostate and fructose level of coagulating gland) also revealed a stimulatory effect of the steroids. 相似文献
74.
75.
Theoretical investigation on the performance of lithium chloride (LiCl) absorption cooling system using an artificial neural network (ANN) model is presented. Tabulated data from the literature are used to construct the ANN model. Solar collector desiccant/regenerator is applied to re-concentrate the working solution. Using the proposed model, the effect of system design parameters; namely regenerator length, and air flow rate on the performance of the system is demonstrated. The variation of the thermo-physical parameters along the regenerator length is highlighted. 相似文献
76.
77.
The differential diagnosis and the duration of symptoms are presented for a group of 288 patients encountered over a ten-year period with a mass in the region of the neck behind and below the angle of the mandible. While infections constituted the largest aetiological group (48.3 per cent), 109 cases (37.9 per cent) had some form of neoplasia, with malignancy being found in 48 (16.6 per cent). The duration of symptoms varied widely, only the acute infections having an acceptably short delay prior to hospital admission. The mean symptom duration for all the neoplastic cases was in excess of five months. 相似文献
78.
In this paper, the electromagnetic and thermal behavior of interstitial applicators was analyzed by using the Finite-Difference Time-Domain method. Two configurations were considered: a simple insulated dipole antenna radiating in a layered tissue, and an air cooled applicator radiating in a tissue-equivalent phantom. The proposed approach allows a detailed modeling of the complete structure of the applicator. Furthermore, Specific Absorption Rate and temperature distributions can be determined considering real clinical or experimental conditions. The temperature distribution for the air cooled applicator has been compared with experimental results. 相似文献
79.
Sporolactobacillus cellulosolvens (NCIMB 12173) isolated from an anaerobic digester and characterised biochemically is being reported for homofermentative lactic acid production from molasses in a batch culture. The effect of various process parameters on lactic acid production were optimized. A maximum lactic acid (24.2 g/l) and yield coefficient (0.79) was achieved using 3% (v/v) inoculum of 36 h old culture in molasses medium containing sugars (5%; w/v) supplemented with peptone (2.5 g/l) and (NH4)2SO4 (7.5 g/l), pH 6.5 at 40 degrees C after 72 h of fermentation. 相似文献
80.
J Hannibal JD Mikkelsen H Clausen JJ Holst BS Wulff J Fahrenkrug 《Canadian Metallurgical Quarterly》1995,55(2):133-148
Pituitary adenylate cyclase activating polypeptide (PACAP) isolated from ovine hypothalamus is considered to be a member of the vasoactive intestinal peptide/glucagon/secretin/growth hormone-releasing hormone family of peptides. Two forms of PACAP, PACAP38 and PACAP27, have been demonstrated in the rat hypothalamus. The PACAP precursor contains another peptide called PACAP-related peptide (PRP), but so far no information on this peptide in tissue exists. We have developed three radioimmunoassays specific for PACAP38, PACAP27 and PRP and demonstrate that all three preproPACAP peptides are expressed in the rat hypothalamus, the PACAP38/PACAP27 ratio being around 60 and the PACAP38/PRP ratio being around 10. HPLC analysis of hypothalamic extract showed that PACAP38 and PACAP27 are found in only one form corresponding to the respective synthetic peptides, whereas PRP eluted in two peaks, the predominant form corresponding to synthetic PRP1-29. The cellular distribution of PACAP38, PACAP27, and PRP and corresponding mRNA in the hypothalamus was determined with immunohistochemistry and in situ hybridization histochemistry. PACAP- and PRP-immunoreactive neuronal perikarya were observed in the medial parvocellular part of the paraventricular nucleus (PVN) in colchicine pretreated rats. Some cell bodies of magnocellular variety were found in the PVN. PACAP mRNA containing cells were observed in moderate numbers in the same parts of the paraventricular nucleus. PACAP- and PRP immunoreactive fibres and varicosities were distributed in the PVN and in the periventricular nucleus. These data show that PACAP38, PACAP27 and PRP are expressed in the parvocellular part of the PVN, implying roles as hypothalamic regulatory peptides. 相似文献