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131.
TC Buchmueller 《Canadian Metallurgical Quarterly》1998,17(6):228-235
In a multiple-option health benefits program, the employer's premium contribution determines the incentives facing employees and participating health plans. Advocates of managed contribution argue that a fixed-dollar contribution policy will result in lower health spending by encouraging cost-conscious choices by employees and price competition among plans. The University of California (UC), which adopted a fixed-dollar contribution policy in 1994, provides a useful case study for assessing this claim. This DataWatch documents the effect of this policy on health maintenance organization (HMO) premiums and per employee health spending in the UC health benefits program. 相似文献
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133.
P Conti M Reale RC Barbacane R Letourneau TC Theoharides 《Canadian Metallurgical Quarterly》1998,12(15):1693-1700
RANTES (regulated upon activation, normal T cell expressed and presumably secreted) and other chemoattractant proteins are members of the intercrine or chemokine family of proinflammatory basic polypeptides. RANTES is a prototype of the C-C chemokine subfamily that acts as a selective chemoattractant for human monocytes and CD4-positive lymphocytes and increases the adherence of monocytes to endothelial cells. However, the role of RANTES in white cells is still unclear. We report here that hrRANTES at 20 ng/50 microl in mice causes mast cell recruitment 4 h after intramuscular injection, an effect inhibited by anti-RANTES, as evidenced by 0.1% Toluidine blue, a specific dye for coloring mast cells. Injections of PBS (50 microl) vehicle (negative control) did not produce any appreciable inflammatory response, whereas injection of lipopolysaccharide 20 ng/50 microl (positive control) generated a marked inflammatory state. When RANTES was injected intramuscularly in genetically mast cell-deficient W/Wv mice, the inflammatory effect was not present. The RANTES injection sites were then excised and studied under an optical and electron microscope. A Northern blot analysis was performed using a probe that was prepared to detect mRNA encoding the histidine decarboxylase (HDC) gene on excised muscle tissue. We found that hrRANTES provoked generation of HDC mRNA from muscle tissue after 4 h. These effects were inhibited by an anti-RANTES antibody and were absent in genetically mast cell-deficient mice. The increasing number of mast cells in the RANTES injection sites led to an augmentation of histamine content compared to controls (PBS). The injection of hrRANTES 20 ng/20 microl into the sole of a rat paw confirmed the inflammatory and the mast cell recruitment potential of this chemokine. In these studies, hrRANTES injections in muscle tissue provided direct in vivo evidence that RANTES has a significant effect on mast cell recruitment and HDC mRNA generation. 相似文献
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135.
A substantial amount of calcium is transferred from the mother to the fetus and infant during pregnancy and lactation. Involvement of the skeleton in meeting this demand should be reflected in changes in bone mass and turnover. The purpose of the study was to determine the effects of pregnancy, lactation, and recovery on the skeleton in 43 young (prepeak bone mass) female monkeys. Whole body (WBBMC) and lumbar vertebrae 2-4 bone mineral content were determined by dual x-ray absorptiometry at baseline and 1, 4, and 10 months postpartum. Alkaline phosphatase, bone Gla protein, and urinary crosslinks were measured at baseline, during the third trimester, and 1, 4, and 10 months postpartum. Compared to nonpregnant, nonlactating monkeys, pregnant monkeys had similar rates of bone mass gain (nonpregnant, nonlactating WBBMC, 25+/-9 mg/day; pregnant WBBMC, 20+/-14 mg/day). Compared to pregnant monkeys, lactating females had increased bone turnover, as indicated by elevated bone biomarker levels (lactating alkaline phosphatase, 259+/-20 IU/L) and decreased bone mass (lactating WBBMC, -99+/-21 mg/day). Densitometry showed that bone mass gain in the lactating monkeys did not compensate for lactational loss by 10 months postpartum (WBBMC, 6.95+/-9 mg/day). This lack of recovery may have been due to the fact that serum estrogen concentrations were just beginning to return to baseline at 10 months postpartum. In conclusion, the cynomolgus monkey skeleton responds similarly to that of women during pregnancy and lactation. Recovery from lactational bone loss is not complete by 10 months postpartum. 相似文献
136.
TM Thompson BL Mark CW Gray TC Terwilliger N Sreerama RW Woody DM Gray 《Canadian Metallurgical Quarterly》1998,37(20):7463-7477
A core Y61F mutant of the gene 5 single-stranded DNA-binding protein (g5p) of f1 bacterial virus aggregated when expressed from a plasmid, but, after refolding in vitro, it behaved much like wild-type and may be a stability or folding mutant. Circular dichroism (CD) titrations showed the same cooperative polynucleotide binding modes for Y61F and wild-type g5p. There are n = 4 and n congruent with 2.5 modes for binding to poly[d(A)] at low ionic strengths, but n = 4, n = 3, and n congruent with 2-2.5 modes for binding to fd single-stranded viral DNA (fd ssDNA), where n is the number of nucleotides occluded by each bound g5p monomer in a given mode. Y61F g5p has slightly reduced affinity in the n = 4 mode. Electron microscopy showed that Y61F g5p forms left-handed nucleoprotein superhelices indistinguishable from wild-type. Progression from binding to fd ssDNA in the n = 4 to n = 3 to n congruent with 2-2.5 mode is accompanied by an increase in the number of helical turns, an increase from (7.7 +/- 0.3) to (9.5 +/- 0.3) to ( approximately 10-13) g5p dimers per turn, and a decrease in the number of DNA nucleotides per turn. From CD spectra for four of five possible Y --> F g5p mutants, we infer that the fifth tyrosine, Tyr 56, contributes strongly to the CD. Retention of a strong 229 nm CD band in all mutants indicates that all retain elements of the native structure. Spectra of Y26F, Y34F, and Y61F g5p imply limited mobility of the replacement Phe. Comparison of measured with calculated CD spectra also suggests limited mobility for Tyr 26 and Tyr 34 in g5p in solution, and provides new information that the g5p structure in solution may be dominated by Tyr 41 rotamers differing from that stabilized in the crystal. 相似文献
137.
SL Anliker MS McClure TC Britton EA Stephan SR Maple GG Cooke 《Canadian Metallurgical Quarterly》1994,83(5):716-719
The anti-tumor agent gemcitabine hydrochloride, a beta-difluoronucleoside, is remarkably stable in the solid state. In 0.1 N HCI solution at 40 degrees C, deamination of gemcitabine occurs, yielding its uridine analogue. Approximately 86% of the initial gemcitabine remains after 4 weeks under these conditions. Cleavage of the N-glycosidic bond of gemcitabine or conversion to its alpha-anomer in 0.1 N HCI solution is not observed over a 4-week period. However, this work has shown that gemcitabine hydrochloride anomerizes in 0.1 N NaOH at 40 degrees C. Approximately 72% of the initial gemcitabine remains after 4 weeks under the basic conditions used. Uridine hydrolysis products are also formed under these conditions. The anormerization reaction, which is unusual under basic conditions, has been confirmed by characterization of the chromatographically isolated alpha-anomer by NMR and mass spectrometry. A mechanism involving an acyclic intermediate is proposed. 相似文献
138.
139.
Osteoprotegerin production by human osteoblast lineage cells is stimulated by vitamin D, bone morphogenetic protein-2, and cytokines 总被引:1,自引:0,他引:1
LC Hofbauer CR Dunstan TC Spelsberg BL Riggs S Khosla 《Canadian Metallurgical Quarterly》1998,250(3):776-781
Rheumatoid arthritis(RA) is a chronic, deforming and destructive arthritis of unknown etiology. For the medical treatment of RA, NSAID has been the first choice of drug. Recently it has been known that early use of DMARD may result in clinical remission. Understanding of the pivotal role of cytokines and adhesion molecules for the rheumatoid joint destruction enabled us to target these cytokines and molecules as therapeutic measures. Monoclonal antibodies were produced against the cytokines and adhesion molecules such as IL-1, IL-6, IL-6R, TNF-alpha, as well as CD4 molecules. Clinical use of these monoclonal antibodies was found to be effective for rheumatoid arthritis. However these therapeutic measures have several disadvantages such as transient efficacy and side effect. 相似文献
140.
CC Szeto CC Chow KY Li TC Ko VT Yeung CS Cockram 《Canadian Metallurgical Quarterly》1996,35(3):289-291
We report a case of oesophageal disease as the first manifestation in a patient with CREST syndrome. A 46-year-old man with achalasia-like syndrome developed CREST syndrome 4 years later. A pneumatic dilatation of the cardia was performed. After pneumatic dilatation the dysphagia and regurgitation disappeared but the patient developed reflux oesophagitis. Four years after diagnosis of oesophageal disease he presented with a clinical picture of CREST syndrome. An acute ileus and constipation developed later. After receiving medical therapy with omeprazole and cisapride the patient is free of oesophageal symptoms and bowel movements are normal. Oesophageal disease is common in patients with limited and diffuse scleroderma, but to our knowledge achalasia-like syndrome has not been previously described as the first manifestation of the systemic disease. 相似文献