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1.
The physiological effects on submaximal and maximal exercise of three methods commonly used by athletes for achieving rapid weight loss were determined by measuring cardiorespiratory variables in 62 nonendurance athletes. A mean weight loss of 4.1% was achieved by those who followed either a sauna (SAU), diuretic (DIU), or exercise (ACT) protocol, compared with the average weight loss of 1.2% in the control group. At maximal exercise O2 consumption, O2 pulse, blood lactate concentration, and work load decreased in SAU and DIU groups relative to the ACT group, whereas only a few differences were observed at the aerobic threshold. Weight loss achieved over a 48-h period was less detrimental to an athlete than was a more rapid (24-h) weight reduction achieved through sauna bathing or the use of diuretics. We conclude that not only the quantity of weight loss but also the method itself may limit physical performance.  相似文献   

2.
During 1980-7, 23 pregnancies of 22-38 weeks'' duration were investigated for fetal tachycardia. Twelve were cases of supraventricular tachycardia, eight of atrial flutter, and three cases in which the rhythm varied between supraventricular tachycardia and atrial flutter. In 11 cases the fetus had developed non-immune fetal hydrops before referral; 12 cases were non-hydropic at referral but one of this group of fetuses became hydropic during treatment. No relation was found between the rate or type of arrhythmia and the presence or absence of intrauterine heart failure. One non-hydropic infant was delivered electively prematurely. Maternal antiarrhythmic treatment was instituted in the remaining 22 cases. Conversion of the arrhythmia was achieved with digoxin alone in five cases and with a combination of digoxin and verapamil in nine. Control of the arrhythmia was achieved in seven of the 10 non-hydropic fetuses, and all were delivered at term with no deaths. Of the 12 hydropic fetuses, control was achieved in seven. Only three of the hydropic fetuses were delivered close to term. There were two deaths, both in the hydropic group. Of the whole group, five neonates suffered severe complications of prematurity. In this series the main benefit of treatment appeared to be in prolonging gestation of those hydropic fetuses in which conversion was achieved.  相似文献   

3.
Fifty women with refractory obesity received fenfluramine for 20 weeks. Every two weeks details of weight change, drug dose, degree of anorexia, and any side effects were recorded and plasma was obtained for fenfluramine and norfenfluramine measurements. Of the 41 patients available for final analysis 26 achieved a maximum plateau dose of 160 mg/day. Plasma fenfluramine concentrations did not correlate with the degree of anorexia or with the incidence of side effects other than the severity of dream disturbance. There was a highly significant relation between weight loss and plasma fenfluramine and norfenfluramine concentrations and also between weight loss and the presence of sustained anorexia. Women who achieved mean plateau concentrations over 200 ng/ml lost a mean 8.8 kg while those with concentrations less than 100 ng/ml lost a mean of only 2.1 kg. When fenfluramine is prescribed in refractory obesity the dose should be increased stepwise until either satisfactory weight loss is achieved or troublesome side effects appear.  相似文献   

4.
The navel orangeworm (NOW), Amyelois transitella (Walker), is a major post-harvest pest of tree nuts including walnut, almonds and pistachios. Nitric oxide (NO) was recently discovered to be a potential fumigant under ultralow oxygen conditions for post-harvest pest control. In this study, NO fumigation was evaluated for efficacy against eggs, larvae and pupae of NOW. NO fumigation was found to be similarly effective against NOW on artificial diet and in infested walnuts. Fumigations of 4, 8 and 16 hr with 2.0, 1.0 and 0.5% NO, respectively, achieved complete control of small and large larvae in artificial diet. Complete control of pupae on artificial diet was achieved in 8, 16 and 24 hr fumigations with 2.0, 1.0 and 0.5% NO, respectively. For NOW in infested walnuts, complete control was achieved in 6, 8 and 16 hr fumigations with 1.5, 1.0 and 0.5% NO, respectively, for small larvae; in 4-, 8- and 24-hr fumigations with 2.0, 1.0 and 0.5% NO, respectively, for large larvae; and in 8-, 16- and 24-hr fumigations with 2.0, 1.0 and 0.5% NO, respectively, for pupae. Eggs were more tolerant to NO fumigation than larvae and pupae, and complete control of NOW eggs was achieved in 8- and 16-hr fumigation with 3.0 and 2.0% NO, respectively. This study demonstrated the efficacy of NO fumigation against NOW on walnut and its potential as an alternative post-harvest treatment for the pest.  相似文献   

5.
SUMMARY
The efficacy of monitoring the pea moth ( Cydia nigricana ) in dry-harvested pea fields with pheromone traps was evaluated on commercial farms in Eastern England used by ADAS as back-up monitoring sites. In particular the use of a 'threshold' catch to determine both the need for and timing of insecticide sprays was evaluated. Fields in which 'threshold' catches were achieved had more damage in unsprayed plots than fields in which there were no 'threshold' catches. When two sprays were applied to crops at 'threshold' sites, the timing of the first predicted by the monitoring system, excellent control was achieved with 85% of crops having less than 1% peas damaged, and none more than 2–3%. Incorrectly timed sprays, or even one correctly timed spray, produced erratic control.
Simple assessments of economic loss show that it is unnecessary to spray crops in which a 'threshold' is not achieved. Spraying 'threshold' crops, however, is very worthwhile and applying two sprays, the first timed with pheromone traps, will be particularly advantageous to both growers of peas for human consumption when 'clean' crops are at a premium, and to seed producers.
The data can be used to predict the probabilities of damage levels, assuming different control strategies.  相似文献   

6.
A first total synthesis of the nucleoside antibiotic herbicidin B (1) was achieved in which a novel aldol-type C-glycosidation reaction promoted by samarium diiodide (SmI2) was used as a key step. Construction of the desired stereochemistry of the tricyclic-sugar moiety was successfully achieved by conformational restriction strategy based on repulsion between adjacent bulky protecting groups on the pyranose ring.  相似文献   

7.
Separation of a mixture of the main cytokinins occurring naturally in plant tissues was achieved by high pressure liquid chromatography using insoluble polyvinylpyrrolidone as the solid support. The separation of each cytokinin was first assessed over a range of salt and l-butanol concentrations and pH using a mixture of borate buffer and l-butanol as the mobile phase to determine the conditions necessary for optimum resolution. A discrete separation of zeatin, N-6-(Delta-2-isopentenyl)adenine, their related ribonucleosides, and kinetin was achieved using a simple isocratic elution with 0.025 m borate buffer at pH 6.8 and 4% (v/v) l-butanol. A number of cytokinin-active compounds were detected in cabbage extracts by the Amaranthus betacyanin bioassay using this separation technique.  相似文献   

8.
Following a period of food deprivation, gibel carp compensated for growth through increased feed intake and conversion efficiency, but increased conversion efficiency was not achieved by increasing digestibility or reducing activity.  相似文献   

9.
Dihydrochalcones are plant secondary metabolites comprising molecules of significant commercial interest as antioxidants, antidiabetics, or sweeteners. To date, their heterologous biosynthesis in microorganisms has been achieved only by precursor feeding or as minor by-products in strains engineered for flavonoid production. Here, the native ScTSC13 was overexpressed in Saccharomyces cerevisiae to increase its side activity in reducing p-coumaroyl-CoA to p-dihydrocoumaroyl-CoA. De novo production of phloretin, the first committed dihydrochalcone, was achieved by co-expression of additional relevant pathway enzymes. Naringenin, a major by-product of the initial pathway, was practically eliminated by using a chalcone synthase from barley with unexpected substrate specificity. By further extension of the pathway from phloretin with decorating enzymes with known specificities for dihydrochalcones, and by exploiting substrate flexibility of enzymes involved in flavonoid biosynthesis, de novo production of the antioxidant molecule nothofagin, the antidiabetic molecule phlorizin, the sweet molecule naringin dihydrochalcone, and 3-hydroxyphloretin was achieved.  相似文献   

10.
A novel class of selective Tie-2 inhibitors was derived from a multi-kinase inhibitor 1. By reversing the amide connectivity and incorporating aminotriazine or aminopyridine hinge-binding moieties, excellent Tie-2 potency and KDR selectivity could be achieved with 3-substituted terminal aryl rings. X-ray co-crystal structure analysis aided inhibitor design. This series was evaluated on the basis of potency, selectivity, and rat pharmacokinetic parameters.  相似文献   

11.
Using an expression vector containing p(mxaF'), a strong native promoter, expression of a model heterologous protein, haloalkane dehalogenase, from Xanthobacter autotrophicus GJ10 was achieved in the methylotrophic bacterium, Methylobacterium extorquens AM1. Although expression using the wild-type strain was <5% of total cell protein, expression at a level of 10% of the total cell protein was achieved in a mutant unable to synthesize poly-beta-hydroxybutyrate granules. Two other tested heterologous proteins, catechol dioxygenase and green fluorescent protein, were expressed at moderate levels in both wild-type and the PHB-negative strain. These results suggest that the M. extorquens PHB-negative strain is a possible platform for overexpression of heterologous proteins with labeled or unlabeled methanol as a starting material.  相似文献   

12.
Strong adherence of bacteria, yeast, erythrocytes, leukocytes, platelets, spores, and polystyrene spheres to membrane filter materials was noted during filtration through membranes with pore size diameters much larger than the particles themselves. Quantitative recovery on the membrane filters of these particles from low-concentration suspensions was achieved during gravity- or vacuum-assisted filtration through membranes with pore diameters as much as 30 times that of the filtered particles. Mechanical sieving was not responsible. The phenomenon was judged to be electrostatic. It could be partially blocked by pretreating the filter with a nonionic surfactant (Tween 20), and elution of adherent particles was achieved with 0.05% Tween 20. Gram-positive cocci were removed from suspension more efficiently than gram-negative rods. The commonly used cellulose membranes adsorbed more bacteria, blood cells, and other particles than did polycarbonate filters. Of lesser adsorptive capacity were vinyl acetate, nylon, acrylic, and Teflon membranes. Backwashing with saline, serum, 6% NaCl, dextran solutions, or phosphate buffers of varying molality and pH removed only a fraction of adherent particles. Tween 20 (0.05%) eluted up to 45% of adherent particles in a single back-filtration. Selected filters quantitatively removed the particles tested, which then could be washed and subjected to reagents for a variety of purposes. It is important to anticipate the removal of particles during membrane filtration, since it is not a simple mechanical event.  相似文献   

13.
14.
In this work, the simultaneous application of bipolar electrodes and a longer cathodic compartment length without agents addition was used as an enhanced electrokinetic treatment of Ni-, Cd-, and Pb-contaminated sediment. Conventional and enhanced treatments were investigated and their efficacy assessed by comparing the residual metals content in the sediment with values given by Dutch standards. After conventional treatment removals of 20%, 19%, and 31% for Ni, Cd, and Pb were achieved, whereas the enhanced treatment achieved removal efficacies of 36% for Ni, 42% for Cd, and 43% for Pb. Results indicate that the simultaneous application of the techniques mentioned is effective for removing Ni and Pb whereas Cd was not removed to the desired level. Here we show that the addition of chemicals is not necessary to increase the efficacies of electrokinetic sediment treatments, so the simultaneous application of the techniques mentioned can be described as environmentally friendly.  相似文献   

15.
The synthesis of suitably protected 1-methyladenosine derivatives has been developed and its successful chemical incorporation into oligonucleotides was achieved.  相似文献   

16.
The complete degradation of Yperite (bis(2-chloroethyl) sulfide), a chemical warfare agent, was achieved by two basidiomycetous cultures. Two distinct metabolic pathways were detected in each fungus during degradation of Yperite. The major path involved a non-enzymatic hydrolysis to generate thiodiglycol. In the minor path, the sulfide bond was cleaved prior to the hydrolytic dechlorination reaction, yielding chloroethanol and chloromercaptoethane, both of which were then metabolized completely.  相似文献   

17.
Screen-printed amperometric glucose biosensors have been fabricated using a water-based carbon ink. The enzyme glucose oxidase (GOD) and the electro-catalyst cobalt phthalocyanine were mixed with the carbon ink prior to the screen-printing process; therefore, biosensors are prepared in a one-step fabrication procedure. Optimisation of the biosensor performance was achieved by studying the effects of pH, buffer strength, and applied potential on the analytical response. Calibration studies were performed under optimum conditions, using amperometry in stirred solution, with an operating potential of +500 mV versus SCE. The sensitivity was found to be 1170 nA mM(-1), with a linear range of 0.025-2 mM; the former represents the detection limit. The disposable amperometric biosensor was evaluated by carrying out replicate determinations on a sample of bovine serum. This was achieved by the method of multiple standard additions and included a correction for background currents arising from oxidizable serum components. The mean serum concentration was calculated to be 8.63 mM and compared well with the supplier's value of 8.3 mM; the coefficient of variation was calculated to be 3.3% (n=6).  相似文献   

18.
Twenty-four different strains of Streptomyces spp. isolated from Egyptian soil were tested for their ability to produce extracellular xylanases. Of all these isolates a Streptomyces sp. that had the highest potential for xylanolytic activity was chosen. From various morphological, physiological and antagonistic properties, this isolate was found to belong to Streptomyces lividans. Factors affecting xylanase production by this organism in a basal salt medium containing purified sugar-cane bagasse xylan as a sole carbon source were examined. A noticeable increase in enzyme activity was observed in the presence of peptone or soyabean meal. However, a slight increase was noticed with ammonium sulphate. Optimum production for xylanase was achieved after five days incubation on a rotary shaker (180 rpm) at 30 degrees C. The initial pH values were around neutrality. In addition, this organism has high potential for xylanolytic activity when grown on lignocellulosic wastes including corn cobs, wheat bran, peanut shells, sawdust, wheat straw and sugar-cane-bagasse. Partial purification of the enzyme in the culture supernatant was achieved by salting out at 50-80% ammonium sulphate saturation with a purification of 9.03-fold and 57.9% recovery.  相似文献   

19.
Powdery mildew infection of barley seedlings was significantly reduced using either pre-inoculation or post-inoculation sprays of the film-forming polymers Nu-Film P, Emerald or Vapor Gard. The greatest reduction in mildew infection was obtained with a pre-inoculation spray of the polymer Vapor Gard. Although the addition of 1 mm α-difluoromethylornithine (DFMO) to a 2% solution of Emerald or Vapor Gard resulted in better control of powdery mildew infection than that obtained using the polymer or DFMO alone, the reductions in infection were not significant. Reduction in mildew infection was greatest when the Vapor Gard + DFMO mixture was applied 1 day prior to inoculation with the fungus. Although substantial reduction in mildew infection was achieved using as little as 0.1 mm DFMO with 2% Vapor Gard, or reducing the polymer concentration to 1% in combination with 1 mm DFMO, best control was achieved using 2% Vapor Gard plus 1 mm DFMO.  相似文献   

20.
We developed an experimental model to compare the efficacy of free vascularized bone grafts, conventional segmental autografts, matchstick autografts, and fresh segmental allografts in terms of their ability to reconstruct a 7-cm segmental diaphyseal defect created in the canine femur. Forty-five adult mongrel dogs were studied and followed for 6 to 12 months prior to sacrifice. Evaluation included radiologic assessment of graft incorporation and hypertrophy, histology, and biomechanical testing. These studies indicated that microsurgically revascularized autografts were superior to all other groups in terms of early incorporation, hypertrophy, and the highest mechanical strength to failure. Union of the bone graft to the recipient femur was achieved by 6 months in 25 of 26 autografts, and no difference in union rate was seen within the autograft group. However, only two of five allografts achieved bony union during this time interval. Arteriography, microangiography, fluorochrome, and histologic studies all supported the concept that microsurgically revascularized grafts, when successful, maintain their viability. However, the premise that all osteocytes survive in a successfully revascularized bone graft is open to question. While decalcified sections showed that all microsurgically revascularized grafts maintained normal viability in the central marrow and cancellous portions compared with the other three groups, the viability of cortical bone in the vascularized autografts was less clear. Undecalcified fluorochrome sections suggested that circulation was not preserved in all portions of the cortex. Revascularization of the nonvascularized autografts was complete at 3 months, while, in the avascular allografts, the process was not complete at 6 months.  相似文献   

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