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排序方式: 共有732条查询结果,搜索用时 15 毫秒
91.
92.
After extraction by treatment with Ecteola-cellulose, IgA 11 S and IgA 7 S from human bronchial secretion were first separated by thin-layer gel filtration in Ultrogel AcA 3-4, and then were analyzed by crossed immunoelectrophoresis with an immune serum against alpha chain. Precipitation areas were measured separately. A correlation factor was necessary to express IgA 7 S in terms of IgA 11 S: it was calculated with standard curves made with serum and colostral IgA. 相似文献
93.
J. Laine F. Severino R. Golding 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1984,34(7):387-393
A series of trimetallic (NiCoMo) hydrodesulphurisation supported catalysts were prepared using a successive impregnation method, varying the ratio of promoters Ni/(Ni + Co) and maintaining the ratio (Ni + Co)/Mo constant. Optima for higher thiophene hydrodesulphurisation activity were found for ratios Ni/(Ni + Co) of 0.7 and 0.8. It is suggested that the optima may be strongly dependent on method of catalyst preparation, and/or type of support employed. Presulphidation was found to increase the activity in NiMo more than in CoMo. Testing of commercial catalysts confirmed various differences between CoMo and NiMo catalysts. 相似文献
94.
L Halme JH Meurman P Laine K von Smitten S Syrj?nen C Lindqvist I Strand-Pettinen 《Canadian Metallurgical Quarterly》1993,76(2):175-181
The frequency and type of oral mucosal lesions, dental infections, and salivary constituents were evaluated in 53 patients with Crohn's disease, who were divided into inactive, mildly active, and severely active groups on the basis of clinical and endoscopic criteria. Buccal biopsies from nine patients with active disease showed morphologic changes that suggested Crohn's disease-related lesions. Panoramic radiographs revealed more infectious foci in the teeth of patients with active Crohn's disease than in patients with inactive disease. Salivary flow rate, buffering capacity, total protein, amylase, and IgA and IgG concentrations did not differ with respect to the activity of Crohn's disease. The observed mucosal inflammation in patients with active Crohn's disease, although high in frequency, was mild and did not need therapy, but the great number of dental infections in association with the activity of Crohn's disease should be taken into account in the treatment of these patients. 相似文献
95.
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97.
Weathering and internal dissolution processes in mining waste materials may mobilize elevated levels of arsenic (As), contaminating ground and surface waters. Treating the polluted waters with iron oxyhydroxides is an established remediation method. By contrast, little knowledge is available to stabilize As in source materials by treating it with Fe precipitates and, on this way, to prevent the generation of polluted waters. In the present work the efficiency of Fe(II) treatment on As immobilization in a tailings material (TM) was studied with regard to the Fe:As molar ratio, the influence of CaCO3 amendment, and the As desorption at continued intensive leaching of Fe-treated TM. Fe precipitates were created by aerobic treatment of TM with Fe(II)sulfate at several Fe:As molar ratios with or without adding CaCO3, followed by aging the Fe-treated TM. The As retention in the treated tailings was studied by 4-fold elution with water, and the As desorption kinetics was examined by suspension leaching in laboratory microcosms over 3 weeks. Fe(II) treatment of TM reduced the water-extractable total As to <10 microg/L as the Fe:As molar ratio increased from 0 to 8. The water-soluble As of Fe-treated tailings could be reduced to 10-30 microg/L also under conditions of intensive leaching. Stabilizing the pH with CaCO3 resulted in consistently higher As release. The As desorption data followed the first-order kinetics in the early time stages of the desorption whereas at longer times the parabolic diffusion model was valid. 相似文献
98.
A Joutti J Brotherus O Renkonen R Laine W Fischer 《Canadian Metallurgical Quarterly》1976,450(2):206-209
After bilateral lesion of the posterior lateral thalamic nucleus in rats, studies been made of motor-feeding reflexes to light stimuli. Using spatial preference technique, it was shown that lesion of this nucleus (representing a part of the retino-tecto-thalamo-cortical system) disturbs differentiation of spatially uncoupled visual stimuli. These data confirm the idea on telencephalization of ancient retino-tectal part of the visual system in evolution and indicate that this part is involved into the analysis of spatial relationships. 相似文献
99.
Biosynthesis and structure of glycosyl diglycerides,steryl glucosides,and acylated steryl glucosides
A particulate enzyme fraction from Mycobacterim smegmatis catalyzed the transfer of -14C-glucose from the UDP--14C-glucose into neutral glycolipids. The two major radioactive components were purified by column chromatography on O-diethylamino ethyl cellulose (acetate) and thin layer chromatography on silica gel in several solvents. The first product yielded a water-soluble component upon saponification, which had a hexoseglycerol ratio of 1:1 with all of the hexose being identified as glucose. The second product yielded a water-soluble component upon saponification which contained hexose and glycerol in a 2:1 ratio and, in addition to glucose, contained lesser amounts of mannose and galactose. Palmitate and oleate were the predominant fatty acids and were present in equimolar amounts. The products thus have been identified as monoglycosyldiglyceride and diglycosyldiglyceride. The diglycosyldiglyceride could also be labeled with -14C-galactose when UDP--14C-galactose served as the donor, but the monoglycosyldiglyceride was only slightly labeled with -14C-galactose. Membrane fractions from mung bean seedlings catalyzed the transfer of -14C-glucose from UDP--14C-glucose into a neutral glycolipid which has been purified by thin layer chromatography and analyzed by combined gas liquid chromatography-mass spectrometry. It was determined to be a steryl glucoside with the two major sterol components being betasitosterol and stigmasterol linked to beta-D-glucose. Particulate fractions from developing cotton fibers also catalyzed the formation of steryl glucosides and, in addition, they catalyzed the esterification of steryl glucosides at the 6 position of glucose with fatty acids (primarily palmitate and oleate) from an andogenous acyl donor. Both the glucosyl transferase and the acyltransferase have been solubilized with Triton X-100 and partially purified by chromatography on Sephadex G-200. The acyltransferase activity was reconstituted by the addition of the steryl glucoside and a phospholipid acyl donor. 相似文献
100.
Li Meng Verena Coleman Yu Zhao Mario Ost Anja Voigt Annelies Bunschoten Jaap Keijer Katja Teerds Susanne Klaus 《International journal of molecular sciences》2021,22(7)
In the present investigation, we examined whether a change in whole body energy fluxes could affect ovarian follicular development, employing mice ectopically expressing uncoupling protein 1 in skeletal muscle (UCP1-TG). Female UCP1-TG and wild-type (WT) mice were dissected at the age of 12 weeks. Energy intake and expenditure, activity, body weight and length, and body composition were measured. Plasma insulin, glucose, leptin, plasma fibroblast growth factor 21 (FGF21) and plasma insulin-like growth factor 1 (IGF1) levels were analyzed and ovarian follicle and corpus luteum numbers were counted. IGF1 signaling was analyzed by immunohistochemical staining for the activation of insulin receptor substrate 1/2 (IRS1/2) and AKT. UCP1-TG female mice had increased energy expenditure, reduced body size, maintained adiposity, and decreased IGF1 concentrations compared to their WT littermates, while preantral and antral follicle numbers were reduced by 40% and 60%, respectively. Corpora lutea were absent in 40% of the ovaries of UCP1-TG mice. Phospho-IRS1, phospho-AKT -Ser473 and -Thr308 immunostaining was present in the granulosa cells of antral follicles in WT ovaries, but faint to absent in the antral follicles of UCP1-TG mice. In conclusion, the reduction in circulating IGF1 levels due to the ectopic expression of UCP1 is associated with reduced immunostaining of the IRS1-PI3/AKT pathway, which may negatively affect ovarian follicle development and ovulation. 相似文献