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91.

Purpose  

An open-label Phase 1 study of recombinant prime-boost poxviruses targeting CEA and MUC-1 in patients with advanced pancreatic cancer was conducted to determine safety, tolerability and obtain preliminary data on immune response and survival.  相似文献   
92.
Background: Intervention trials with self-selected participants have shown that mailed stage-targeted print materials can increase participation in physical activity in the short term. We examined the effects of a mailed stage-targeted print intervention designed to promote physical activity, in a random sample of adults living in a regional city.Method: Participants (n = 462, 40–60 years of age) were randomly allocated to an intervention in - 227) or control group (n - 235). Measures included validated 2-week physical activity recall and stage of motivational readiness for physical activity. The intervention consisted of a single mailing of a letter and full-color stage-targeted booklets (specific to precontemplation, contemplation, preparation, and action/maintenance) 1 week postbaseline. Follow-up interviews were conducted at 2 and 6 months postbaseline.Results: After 2 months, participants in the intervention group were significantly More likely to meet the current American College of Sports Medicine/Centers for Disease Control and Prevention recommendation for sufficient physical activity than those in the control group (adjusted odds ratio [OR] - 2.40; 95% confidence interval [CI] = 1.44–3.99). After 6 months, intervention participants who reported receiving and reading the intervention materials were significantly more likely to be meeting the sufficient physical activity criterion compared with the control group (adjusted OR = 2.03; 95% Cl = 1.16–3.56).Conclusions: The stage-targeted print intervention was effective in promoting short-term increases in physical activity and was most effective for participants who recognized and used the materials. This low-cost, generalizable intervention has demonstrated potential as a practical population-based physical activity promotion strategy. Further research is required before widespread dissemination would be justified, as additional strategies may be required to ensure sustained change. This project was supported by a National Heart Foundation of Australia Research Project Grant. David Crawford was supported by a Nutrition Research fellowship from the National Heart Foundation.  相似文献   
93.
Systematic series of monoamines, diamines, and triamines were used to define the structural requirements for interaction at the polyamine recognition site of the N-methyl-D-aspartate receptor complex. Effects of amines on binding of [3H]MK-801 to washed synaptic plasma membranes were measured in the presence of L-glutamate and glycine (100 microM each), in the absence or presence of spermine (10 microM). Linear aliphatic monoamines of methylene chain length up to 12 (dodecylamine) did not interact with the polyamine recognition site. Nonspecific inhibition of binding was observed at high concentrations of the longer monoamines. alpha,omega-Diamines of methylene chain length 2 (1,2-diaminoethane, DA2) through 12 (1,12-diaminododecane, DA12) had varying actions, depending on chain length. The shortest diamines (DA2 and DA3) acted as weak partial agonists, enhancing the binding of [3H[MK-801. Intermediate-length diamines (DA4-DA7) were selective polyamine antagonists, having little or no effect on binding of [3H]MK-801 measured in the absence of spermine but inhibiting binding measured in the presence of spermine. The longest diamines tested (DA8-DA12) acted as inverse agonists; they inhibited binding in the absence or presence of spermine, and this inhibition was blocked by the selective polyamine antagonist diethylenetriamine. Computer modeling of conformations of the diamines quantitatively documented that 1) these molecules are flexible and 2) long diamines may easily adopt conformations with inter-nitrogen distances mimicking those of short diamines. The cis and trans isomers of 1,4-diaminocyclohexane are inflexible, conformationally restricted diamines with markedly different actions. The cis isomer was a partial agonist and the trans isomer was an antagonist at the polyamine recognition site. Triamines of general structure NH2(CH2)3NH(CH2)xNH2 (TRI[3,x]), in which x = 3-12, were synthesized and tested for activity at the polyamine recognition site. Despite the large range of size, TRI[3,3] through TRI[3,9] were all fully polyamine agonists of similar potency. TRI[3,10] was a partial agonist, whereas TRI[3,12] inhibited binding of [3H]MK-801. Diethylenetriamine did not attenuate the effect of TRI[3,12]. Based on the results of the radioligand binding studies and the computer analysis, a model of the polyamine recognition site is proposed.  相似文献   
94.
Collagens in ocular tissues.   总被引:4,自引:2,他引:2       下载免费PDF全文
  相似文献   
95.
1. Cultured elicited-peritoneal macrophages release a soluble type II 14 kDa phospholipase A2 (PLA2) over time, reaching a plateau by 20-24 h of incubation and maintaining these levels over 72 h. Prostaglandin E2 (PGE2) is also produced but does not plateau until 48-72 h. 2. Transforming growth factor beta 1 (TGF beta 1) reduces cellular 14 kDa PLA2 and its subsequent release by approximately half, but does not alter PGE2 production. Co-incubation of TGF beta 1 with indomethacin interfered, in a concentration-dependent manner, with the ability of TGF beta 1 to reduce cellular 14 kDa PLA2 and its subsequent release over 24 h. The regulation of TGF beta 1 was not specific to indomethacin since other non-steroidal anti-inflammatory drugs had the same effect. This suggested that cyclooxygenase activity was essential for TGF beta 1 to exert its effect and indeed, the addition of exogenous PGE2 restored the TGF beta 1 action. 3. PGE2 alone exerted a concentration-dependent negative feedback action on elicited-macrophage 14 kDa PLA2 release. The inhibitory concentration (IC50 = approximately 180 ng PGE2 ml-1) approximated the PGE2 levels measured in the 24 h macrophage conditioned media (85-140 ng PGE2 ml-1) where PLA2 release began to plateau. Further, incubation of cells with indomethacin over 48 h resulted in the enhancement of 14 kDa PLA2 activity compared to that released from untreated cells. Forskolin failed to inhibit 14 kDa PLA2 release, suggesting PGE2 was not acting through an increase in adenylate cyclase. 4. Taken together, the data are consistent with the immunosuppressive aspects reported for both mediators during inflammation and demonstrates the requirement of PGE2 for TGF beta 1 action on the elicited macrophage.  相似文献   
96.
The marine natural product, manoalide (MLD), was investigated to determine if this drug inhibited purified human synovial fluid phospholipase A2 (HSF-PLA2). Utilizing classical Michaelis-Menten kinetics, apparent Km and Vmax values for HSF-PLA2 of 1.34 mM and 0.47 mumol [3H]palmitic acid released/min/mg protein were obtained using dipalmitoylphosphatidylcholine (DPPC) as the substrate, and 38.0 microM and 18.8 mumol [3H]arachidonic acid released/min/mg protein with Escherichia coli as a natural substrate. These kinetic parameters were utilized subsequently to evaluate the inhibitory effects of manoalide on HSF-PLA2. Inhibition of HSF-PLA2 by MLD was concentration and time dependent with IC50 values of 0.2 and 0.02 microM for DPPC and E. coli respectively. Dialysis studies and examination of DPPC or E. coli hydrolysis versus enzyme concentration indicate that MLD is an irreversible inhibitor of HSF-PLA2. Substrate specificity was also examined in the absence and presence of MLD using dipalmitoylphosphatidylethanolamine (DPPE) as a substrate. MLD inhibited the hydrolysis of DPPE (greater than 90% inhibition at 2 microM), and preliminary results indicate that DPPC was more readily hydrolyzed than DPPE under the substrate conditions of the assay. While the cellular source of secreted HSF-PLA2 is unknown, these studies indicate that MLD can inactivate secreted phospholipase A2 isolated from patients with inflammatory joint disease.  相似文献   
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99.
A follow-up study was conducted in December 1987 on all 136 women between the ages of 25 and 64 years who had been recorded as being on treatment for hypertension in the Mamre Community Health Project in December 1986. A further 136 women were randomly selected from the same age category to determine the overall prevalence of hypertension. The repeatability and validity of the 1986 project questionnaire were satisfactory. The overall prevalence of hypertension in Mamre women was 25.9% (16.1% for the age group 25-44 years and 38.4% for the age group 44-64 years). The extent of underdiagnosis of hypertension in the community on the basis of the 1986 survey was 56.8%. Despite a good reported compliance rate of 72.7%, 56.3% of hypertensives were not adequately controlled. The Mamre community presents an ideal setting for an interventive study in the management of hypertension.  相似文献   
100.
Aberrant epididymal tissue: a significant clinical entity   总被引:1,自引:0,他引:1  
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