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971.
OBJECTIVES--To determine what proportion of oncology patients receiving conventional medical treatment also use complementary treatments; to assess which complementary treatments are the most popular and to assess patients'' motivation for using them; to evaluate associated advantages and risks. DESIGN--Postal screening questionnaire followed by semistructured interview. SETTING--Two hospitals in inner London. SUBJECTS--600 unselected oncology patients aged 18 or over who had known their diagnosis of cancer for at least three months. MAIN OUTCOME MEASURES--Prevalence and demography of use of complementary therapies; patients'' motivation and expectations of complementary therapies; areas of satisfaction and dissatisfaction associated with conventional and complementary therapies. RESULTS--415 (69%) patients returned the questionnaire. 16% had used complementary therapies. The most popular were healing, relaxation, visualisation, diets, homoeopathy, vitamins, herbalism, and the Bristol approach. Patients using complementary therapies tended to be younger, of higher social class, and female. Three quarters used two or more therapies. Therapies were mostly used for anticipated antitumour effect. Ill effects of diets and herb treatments were described. Satisfaction with both conventional and complementary therapies was high, although diets often caused difficulties. Patients using complementary therapies were less satisfied with conventional treatments, largely because of side effects and lack of hope of cure. Benefits of complementary therapies were mainly psychological. CONCLUSIONS--A sizeable percentage of patients receiving conventional treatments for cancer also use complementary therapies. Patient satisfaction with complementary therapies, other than dietary therapies, was high even without the hoped for anticancer effect. Patients reported psychological benefits such as hope and optimism.  相似文献   
972.
Predation and antipredator behavior are important but poorly studied influences on the evolution of primate societies. I review recent evidence of predation and antipredator strategies among primates. I describe patterns of antipredator behavior and attempt to explain the variation among primate taxa and among antipredator strategies. I use predation by chimpanzees on red colobus and antipredator strategies by the colobus as a case study of how a primate prey species may respond to the threat of predation.  相似文献   
973.
A rapid method for assessing the lytic activity of antimicrobial agents against yeast and fungi has been developed. The assay is based on the release of the intracellular enzyme, maltase (alpha-glucosidase). The released maltase activity was measured colorimetrically by the production of p-nitrophenol from p-nitrophenyl-alpha-D-glucopyranoside (PNPG). The lytic activity of different antimicrobial compounds was measured against yeast cells or germinating spores of filamentous fungi. Lytic anti-yeast activity could be detected within 20 min incubation at 30 degrees C against Saccharomyces cerevisiae, Candida albicans, and Cryptococcus neoformans. Lytic anti-fungal activity appeared after 2 h of incubation at 30 degrees C against germinating spores of Aspergillus niger and Botrytis cinerea. Whole cells of either yeast or fungi did not hydrolyze sufficient PNPG within 3 h at 30 degrees C to yield a detectable color change. Lytic activity of enzymes (e.g., Lyticase), antibiotics (e.g., Amphotericin B), and an antibiotic-producing strain of bacteria were detected using the assay. The anti-yeast assay has been adapted to a 96-well microtiter format. Both assays provided a rapid, sensitive, and reproducible detection of lytic anti-yeast and anti-fungal activity.  相似文献   
974.
1. Aerobic respiration, productivity and the carbon turnover rate of microbial biofilms were determined at hyporheic and phreatic sites in the Kalispell Valley alluvial aquifer along a transect extending 3.9 km laterally from the main channel of the Flathead River, a sixth order river in Montana (U.S.A.). The effect of experimentally increasing bioavailable organic carbon (acetate) on the respiration rate of biofilms in this carbon‐poor [dissolved organic carbon (DOC) < 2 mg L?1] aquifer was also measured. 2. Chambers containing natural substratum were placed in‐situ and allowed to colonise for 20 weeks. After 4, 12 and 20 weeks, they were taken to the laboratory where oxygen flux was measured in a computer‐controlled, flow‐through respirometry system. 3. Respiration ranged from 0.01 to 0.33 mg O2 dm?3 h?1 across sites, with means ranging from 0.10 to 0.17 mg O2 dm?3 h?1. Productivity estimates ranged from 0.18 to 0.32 mg C dm?3 day?1 (mean 0.25, SE 0.03). The total organic carbon (TOC) of the microbial biofilms ranged from 18.2 to 29.7 mg C dm?3. Turnover rate ranged from 3.2 to 5.6 year?1 with a mean of 4.2 year?1. 4. At the hyporheic site very close to the river, respiration did not significantly increase when samples were supplemented with labile carbon. Respiration increased with increasing DOC addition at hyporheic sites more distant from the river, suggesting a carbon‐limitation gradient within the hyporheic zone. Microbes at the phreatic site did not respond to increasing DOC addition, suggesting that the phreatic biofilm is adapted to low carbon availability. 5. Comparing the volume of the alluvial aquifer (about 0.7 km3) to that of the river benthic sediments (to 0.25 m depth, which amounts to about 1.6 × 10?4 km3) within the Flathead Valley, leads to the conclusion that interstitial microbial productivity is orders of magnitude greater than benthic productivity. Alluvial aquifers are often voluminous and microbial production is an enormous component of ecosystem production in rivers such as the Flathead.  相似文献   
975.
Immunomodulatory drugs could contribute to a functional cure for Human Immunodeficiency Virus (HIV). Interleukin-15 (IL-15) promotes expansion and activation of CD8+ T cell and natural killer (NK) cell populations. In one study, an IL-15 superagonist, N-803, suppressed Simian Immunodeficiency Virus (SIV) in non-human primates (NHPs) who had received prior SIV vaccination. However, viral suppression attenuated with continued N-803 treatment, partially returning after long treatment interruption. While there is evidence of concurrent drug tolerance, immune regulation, and viral escape, the relative contributions of these mechanisms to the observed viral dynamics have not been quantified. Here, we utilize mathematical models of N-803 treatment in SIV-infected macaques to estimate contributions of these three key mechanisms to treatment outcomes: 1) drug tolerance, 2) immune regulation, and 3) viral escape. We calibrated our model to viral and lymphocyte responses from the above-mentioned NHP study. Our models track CD8+ T cell and NK cell populations with N-803-dependent proliferation and activation, as well as viral dynamics in response to these immune cell populations. We compared mathematical models with different combinations of the three key mechanisms based on Akaike Information Criterion and important qualitative features of the NHP data. Two minimal models were capable of reproducing the observed SIV response to N-803. In both models, immune regulation strongly reduced cytotoxic cell activation to enable viral rebound. Either long-term drug tolerance or viral escape (or some combination thereof) could account for changes to viral dynamics across long breaks in N-803 treatment. Theoretical explorations with the models showed that less-frequent N-803 dosing and concurrent immune regulation blockade (e.g. PD-L1 inhibition) may improve N-803 efficacy. However, N-803 may need to be combined with other immune therapies to countermand viral escape from the CD8+ T cell response. Our mechanistic model will inform such therapy design and guide future studies.  相似文献   
976.
Airborne Pollen grains and Spores of three different cities viz., Al-Khobar (1987–1988), Abha (1991–1992) and Hofuf (1992–1993) in Saudi Arabia were studied using Burkard Volumetric Seven-Day Spore Trap. The data were analyzed in relation to their allergenic capability and one-year pollen and spore calendars were designed to correlate the patients’ symptoms as well as for selection of appropriate allergen extracts for diagnosis and treatment of allergic diseases. Amongst pollen group, Amaranthus viridis, Plantago spp., Chenopodium album, Ricinus communis, Rumex vesicarius, Juniperus spp., Parkinsonia aculeata, Prosopis spp., and Phoenix dactylifera were some of the frequent types. Amongst the fungal spores group Cladosporium, Smuts spores, Colored basidiospores, Alternaria, Ulocladium and Drechslera were the dominant types.  相似文献   
977.
Substituted 9H-pyrido[3,4-b]indoles (beta-carbolines) identified in our laboratory as potential pharmacophore for designing macrofilaricidal agents, have been explored further for identifying the pharmacophore responsible for high order of adulticidal activity. This has led to syntheses and macrofilaricidal evaluations of a number of 1-aryl-9H-pyrido[3,4-b]indole-3-carboxylate derivatives (3-7). The macrofilarical activity was initially evaluated in vivo against Acanthoeilonema viteae. Amongst all the synthesized compounds, only twelve compounds namely 3a, 3c, 3d, 3f, 4c, 4d, 4f, 5a, 6f, 6h, 6i and 7h have exhibited either > 90% micro- or macrofilaricidal activity or sterilization of female worms. These compounds have also been screened against Litomosoides carinii and of these only 3f and 5a have also been found to be active. Finally these two compounds have been evaluated against Brugia malayi. The structure activity relationship (SAR) associated with position-1 and 3 substituents in beta-carbolines have been discussed. It has been observed that the presence of carbomethoxy at position-3 and an aryl substituent at position- in beta-carbolines effectively enhance antifilarial activity particularly against A. viteae. Amongst the various compounds screened, methyl 1-(4-methylphenyl)-9H-pyrido[3,4-b]indole-3-carboxylate (4c) has shown highest adulticidal activity and methyl 1-(4-chlorophenyl)-1,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole-3-carboxyla te (3a) has shown highest microfilaricidal action against A. viteae at 50 mg/ kg x 5 days (i.p.). Another derivative of this compound namely 1-(4-chlorophenyl)-3-hydroxymethyl-9H-pyrido[3,4-b]indole (5a) exhibited highest activity against L. carinii at 30 mg/kg x 5 days (i.p.) and against B. malayi at 50 mg/kg x 5 days (i.p.) or at 200 mg/kg x 5 days (p.o.).  相似文献   
978.
979.
Creatine monohydrate (CrMH) supplementation aids the ability to maintain performance during repeated bouts of high-intensity exercise, including jump performance. However, carbohydrate supplementation may also provide similar benefits and is less expensive. This study compared the effects of an energy-free placebo, 2 different caloric concentrations of carbohydrate drinks, and a CrMH supplement on repeated jump heights. Sixty active males (mean age, 22 +/- 3.2 years) performed 2 sets of countermovement static jump height tests (10 jumps over 60 seconds) separated by 5 days to determine the differential effects of the placebo, carbohydrate, and CrMH on jump height sustainability over 10 jumps. Subjects were randomly assigned to groups (15 subjects per group) to receive daily doses (x5 days) of carbohydrate drinks containing 100 or 250 kilocalories (kcal), a 25-g CrMH supplement, or an energy-free placebo. After 5 days, the CrMH group experienced a significant weight gain (+1.52; +/-0.89 kg, p < 0.01), while the other groups did not. The 2 levels of carbohydrate and CrMH supplements were all significantly better at sustaining jump height than the energy-free placebo over the final 3-4 jumps. The 250-kcal carbohydrate-supplemented group experienced a level of benefit (p < 0.01) that was at least equal to that of the CrMH group (p < 0.05), suggesting that the higher dose of carbohydrate was as effective as CrMH in maintaining repeated bouts of high-intensity activity as measured by repeated static jumps. Given the equivalent performance improvement and the absence of weight gain, the carbohydrate supplementation could be considered the preferred option for weight-conscious power athletes involved in activities that require repeated- motion high-intensity activities.  相似文献   
980.
High-fat feeding (HFF) is a well-accepted model for nutritionally-induced insulin resistance. The purpose of this investigation was to assess the metabolic responses of female lean Zucker rats provided regular chow (4% fat) or a high-fat chow (50% fat) for 15 wk. HFF rats spontaneously adjusted food intake so that daily caloric intake matched that of chow-fed (CF) controls. HFF animals consumed more (P < 0.05) calories from fat (31.9 +/- 1.2 vs. 2.4 +/- 0.2 kcal/day) and had significantly greater final body weights (280 +/- 10 vs. 250 +/- 5 g) and total visceral fat (24 +/- 3 vs. 10 +/- 1 g). Fasting plasma insulin was 2.3-fold elevated in HFF rats. Glucose tolerance (58%) and whole body insulin sensitivity (75%) were markedly impaired in HFF animals. In HFF plantaris muscle, in vivo insulin receptor beta-subunit (IR-beta) and insulin receptor substrate-1 (IRS-1) tyrosine phosphorylation and phosphorylation of Akt Ser473 and glycogen synthase kinase-3beta (GSK-3beta) Ser9, relative to circulating insulin levels, were decreased by 40-59%. In vitro insulin-stimulated glucose transport in HFF soleus was decreased by 54%, as were IRS-1 tyrosine phosphorylation (26%) and phosphorylation of Akt Ser473 (38%) and GSK-3beta Ser9 (25%), the latter indicative of GSK-3 overactivity. GSK-3 inhibition in HFF soleus using CT98014 increased insulin-stimulated glucose transport (28%), IRS-1 tyrosine phosphorylation (28%) and phosphorylation of Akt Ser473 (38%) and GSK-3beta Ser9 (48%). In summary, the female lean Zucker rat fed a high-fat diet represents an isocaloric model of nutritionally-induced insulin resistance associated with moderate visceral fat gain, hyperinsulinemia, and impairments of skeletal muscle insulin-signaling functionality, including GSK-3beta overactivity.  相似文献   
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