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71.
The results of a 15 months' intensive study on seven flocks of indigenous goats in the Southern Darfur region of the Sudan are discussed in this paper. Birth rates in the region approached 2-1 kids per doe per year. A high total offtake of 28 per cent and a weighted average death rate of about 16-5 per cent were insufficient to offset this high birth rate and flock numbers are increased. Mortality in kids was unrelated to number of births. Weighted average rate of gain for all surviving kids was 87 g per day to 3 months and 67 g per day to 6 months of age. The growth rates of twin and single were similar, but triplet kids grew at a slower rate. For each kilogramme liveweight of breeding females, goats produced 1-5 and 8 times the weight of meat produced by sheep and cattle respectively under the same management and environmental conditions.  相似文献   
72.
73.
Lymphocyte-mediated cytotoxicity (cell-mediated immunity) to ovarian carcinoma cells and serum blocking factor were measured in 37 patients. Short-term cultures of tumor cells and a low ratio of effector to target cells were used throughout the study, minimizing nonspecific cytotoxicity. Sixteen patients were followed for long periods of time, and correlation with the course of the disease and with therapy could be obtained. Although the level of cell-mediated immunity did not always correspond to the clinical status of the patient, the presence of blocking factor was associated with clinical relapse in 14 of 16 patients. Chemotherapy with single alkylating agents or combinations of drugs caused no significant or permanent depression of cell-mediated immunity as measured in this way. In addition, blocking factor disappeared in 2 patients during remission. It appears that the chemotherapy for ovarian carcinoma may not be significantly immunosuppressive against established levels of cell-mediated immunity and may in certain instances have effects potentially beneficial to the host as evaluated by lymphocyte-mediated cytotoxicity and blocking factor studies.  相似文献   
74.
Two hundred open heart cases anaesthetized with a combination of diazepam-ketamine using "Micro-Mini" drip administration technique were presented. The results were eminently desirable, and in the opinion of the authors are a notable improvement over other methods for all types of cardiovascular surgery including most advanced heart diseases. The advantages of this anaesthetic method for cardiovascular surgery are as follows: 1. Effects on cardiovascular system are minimal.--2. Respiratory depression is negligible.--3. There is no increase in salivation or muscle tone.--4. Induction and maintenance of anaesthesia are simple and smooth.--5. Anaesthesia can be maintained, using a high concentration of oxygen alone, by a slight increase in rate of ketamine administration whenever necessary.--6. Post-anaesthetic psychotomimetic effects are negligible.--7. Nearly 100% of patients have excellent amnesia.--8. It has a wide margin of safety.--9. This technique has proved highly acceptable to patients and surgeons. We feel ketamine should be used in small dosages continuously administered with either "Micro-Mini" drip infusion or infusion pump. Ketamine given in this fashion should be regarded as an analgesic.  相似文献   
75.
By attaching a piezoelectric transducer that modulates the mechanical tension over a short section of fibre, signals in optical fibres are phase modulated. The technique is applicable to a I-way optical-telemetry system.  相似文献   
76.
ABSTRACT:  Fresh and dried raspberries prepared by freeze drying (FD), microwave-vacuum (MIVAC), hot-air drying (HAD), and a combination of hot-air drying and microwave-vacuum (HAD/MIVAC) drying methods were evaluated for polyphenol retention, total polyphenol and anthocyanin contents, total antioxidant capacity, and antiadipogenic activity (the inhibition of fat cell development). Ellagic acid and quercetin were present in the largest concentrations in fresh and dehydrated raspberries. Dehydration led to a loss of polyphenols and anthocyanins and antioxidant capacity. Polyphenols (aglycone form) were retained in the greatest amount: 20% (freeze dried) to 30% (HAD/MIVAC) (fresh = 100%). A total of 30% of polyphenols (glycoside form) were retained in raspberries dried by the HAD/MIVAC methods with 5% of retention observed for raspberries dried by FD, HAD, or MIVAC. FD and MIVAC resulted in higher retention of anthocyanins (aglycone form) than other drying methods. It was also observed that antioxidant activity was reduced by dehydration. Adipogenesis was inhibited by polyphenolic glycosides (30%) and aglycones (30% to 40%) in fresh and HAD/MIVAC raspberries. Extracts from dried raspberries by HAD/MIVAC methods were relatively more effective at inhibiting adipogenesis compared to HAD and FD dried raspberries.  相似文献   
77.
Heat-resistant spore-forming bacteria such as Bacillus and Clostridium can survive and grow in cooked potato products. This situation represents both a public health problem and an economic problem. The natural food preservative nisin is used in heat-treated foods to prevent the growth of such bacteria. A cocktail of Clostridium sporogenes and Clostridium tyrobutyricum spores was inoculated into cooked mashed potatoes, which were vacuum packed, pasteurized, and incubated at 8 and 25 degrees C. The shelf life of the mashed potatoes at 25 degrees C was extended by at least 58 days with the addition 6.25 microg of nisin per g. At 8 degrees C, in control samples not containing nisin, the natural contaminant Bacillus grew, but the inoculated Clostridium strains did not until the temperature was raised to 20 degrees C after 39 days. No bacterial growth occurred in nisin-containing samples. The shelf life of the mashed potatoes was extended by at least 30 days with 6.25 microg of nisin per g. In trials involving a cocktail of Bacillus cereus and Bacillus subtilis strains, 6.25 microg of nisin per g extended the shelf life of mashed potato samples that were not vacuum packed by at least 27 days at 8 degrees C. At 25 degrees C, 25 microg of nisin per g extended shelf life by a similar period. Shelf life extension was also observed at lower nisin levels. Microbiological analysis of the mashed potato ingredients showed that a high spore level was associated with the onion powder. It is emphasized that the preservative and the ingredients must be well mixed to ensure good nisin efficacy. Nisin remained at effective levels after pasteurization, and good retention was observed throughout the shelf life of the mashed potatoes.  相似文献   
78.
The UK, like the rest of the world, is confronting the impacts of climate change. Further changes are expected and they will have a profound effect on agriculture. Future crop production will take place against increasing CO2 levels and temperatures, decreasing water availability, and increasing frequency of extreme weather events. This review contributes to research on agricultural practices for climate change, but with a more regional perspective. The present study explores climate change impacts on UK agriculture, particularly food crop production, and how to mitigate and build resilience to climate change by adopting and/or changing soil management practices, including fertilisation and tillage systems, new crop adoption and variety choice. Some mitigation can be adopted in the shorter term, such as changes in crop type and reduction in fertiliser use, but in other cases the options will need greater investment and longer adaptation period. This is the case for new crop variety development and deployment, and possible changes to soil cultivations. Uncertainty of future weather conditions, particularly extreme weather, also affect decision‐making for adoption of practices by farmers to ensure more stable and sustainable production. Even when there is real potential for climate change mitigation, it can sometimes be more difficult to accomplish with certainty on‐farm. Better future climate projections and long‐term investments will be required to create more resilient agricultural systems in the UK in the face of climate change challenges. © 2016 Society of Chemical Industry  相似文献   
79.
Alicyclobacillus acidoterrestris in fruit juices and its control by nisin   总被引:2,自引:0,他引:2  
Summary The acid-tolerant and heat-resistant bacterium Alicyclobacillus acidoterrestris is a spoilage problem in pasteurized and heat-treated fruit juices. In this study it was shown to grow in orange juice, grapefruit juice and apple juice to produce detectable taint at levels of about 104–105 c.f.u. ml−1. Decimal reduction times were determined at 80 °, 90 ° and 95 °C in each juice and confirmed the heat-resistant nature of the spores under normal juice pasteurization conditions. They also confirmed that heat sensitivity increased with decreasing pH but that this effect was less pronounced at higher temperatures. The organism was, however, sensitive to the bacteriocin food preservative nisin. The presence of nisin during heating decreased the D value by up to 40% and the MIC for nisin against spores at 25 °C was only 5 International Units (IU) ml−1. The results indicate that use of nisin is a potentially useful way of controlling this organism in fruit juices and fruit juice-containing products.  相似文献   
80.
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