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961.
摘要 目的:分析自拟益气通阳活血方治疗阿尔茨海默病的临床效果。方法:选取2020年10月~2022年4月于中国人民解放军空军军医大学第一附属医院接受治疗的阿尔茨海默病患者104例,依据入院先后顺序编号,按单双号分为对照组(n=52)和研究组(n=52)。对照组进行常规西药治疗,研究组在此基础上进行自拟益气通阳活血方治疗。比较两组临床疗效、治疗前后中医证候积分、日常生活活动能力、认知功能、血清去甲肾上腺素(NE)、多巴胺(DA)、乙酰胆碱转移酶(ChAT)水平、β淀粉样蛋白前体(APP)、β淀粉样蛋白1-42(Aβ1-42)、丙二醛(MDA)、超氧化物歧化酶(SOD)水平,并比较两组安全性。结果:治疗后,两组中医证候积分均降低,且研究组显著低于对照组(P<0.05);研究组总有效率为94.23%,明显高于对照组的78.85%(P<0.05);治疗后,两组简易智能精神状态检查量表(MMSE)评分与蒙特利尔认知评估量表(MoCA)评分研究组均高于对照组(P<0.05);治疗后,两组barthel指数评分及日常生活能力量表(ADL)评分研究组均显著高于对照组(P<0.05);治疗后,两组DA、NE、ChAT水平均升高,且研究组明显高于对照组(P<0.05);治疗后,两组SOD水平升高,APP、Aβ1-42、MDA水平均降低(P<0.05),且与对照组相比研究组各指标变化更显著(P<0.05);两组治疗期间的不良反应均较轻微,经对症处理后均缓解,不良反应发生率比较无明显差异(P>0.05)。结论:自拟益气通阳活血方治疗阿尔茨海默病疗效显著,可降低中医证候积分,提高认知功能,调节NE、DA、ChAT水平,抑制APP、Aβ1-42水平,提高其日常生活活动能力,且安全性高。  相似文献   
962.
beta-Endorphin was injected into the third cerebral ventricle (ICV) of conscious, unrestrained cats. Hyperthermic response to 50 microgram of this peptide were reduced by 20-100 microgram naloxone given ICV 1 hr later. A dose of 40 microgram beta-endorphin increased body temperature at ambient temperature of 4, 22 and 34 degrees C, with the response being greater the warmer the environment. These results indicate that beta-endorphin acts on a central naloxone-sensitive receptor which is probably the v2 receptor that is activated by low doses of D-Ala2-Met-enkephalinamide to evoke a similar pattern of change in body temperature over a comparable range of ambient temperatures.  相似文献   
963.
Differences in high-resolution two-dimensional gel electrophoresis patterns of micro-somal proteins from developing normal sunflower ( Helianthus annuus L.) seeds before and after cold-induction, and also from normal and a high oleic sunflower mutant have been studied in order to detect the polypeptides associated with the microsomal Δl2-desaturase activity and its regulation by temperature. Proteins were obtained from developing seeds of two isogenic sunflower lines HA-89 (normal) and HA-OL9 (high oleic) which greatly differed in linoleic acid content and "in vitro" oleate desaturase activity. In the high oleic mutant, four polypeptides of about 32 kDa and two of 33 kDa were found to change in position, to the same extent, toward a lower isoelectric point in the high oleic mutant. Also, two polypeptides, of 32 and 49 kDa each, appeared in the mutant. Quantitative differences between cold-induced seeds (10°C, 24 h) and their non-induced controls were found. One polypeptide of 43 kDa decreased in the cold-treated seeds and two others, of 30 and 32 kDa each, increased markedly after cold induction. Some of these polypeptides could be related to oleate desatnrase activity or its regulation by temperature.  相似文献   
964.
Africa's large predator guild competes for a limited food resource base. To minimize the degree of competition, we hypothesized that the two largest members of this guild and its fiercest competitors, the lion and the spotted hyaena, would partition their activity patterns to avoid interacting. We used 96‐h continuous follows of focal animal(s) to determine when the six radio‐collared lions and eight radio‐collared spotted hyaenas, reintroduced into Addo Elephant National Park in 2003/2004, were active using a binomial measure of activity which was defined as movements >100 m during each hourly period. Contrary to our predictions, lions and hyaenas did not partition their activity times, probably because of their current low population densities. Both species exhibited a crepuscular activity pattern although hyaenas were far less active during daylight. A sub‐adult lioness minimized competitive interactions by becoming diurnal. This is likely to be a common strategy for lions that have been expelled from their natal pride to become nomadic, as it allows them to minimize kleptoparasitic and agonistic interactions from competitively dominant conspecifics and competitors. The increase in testosterone that occurs in males upon reaching sexual maturity, darkens their pelage and causes them to be more directly impacted by the heat, and thereby affords females an opportunity to escape from males during hot temperatures. Similarly, the longer pelage of young hyaenas restricts their activity to the cooler night‐time.  相似文献   
965.
1 The spatial and temporal distribution of pine woolly aphids, Pineus boerneri (Homoptera: Adelgidae) a pest of exotic pine trees in Malawi, was investigated in 5‐year‐old Pinus kesiya trees. 2 Pineus boerneri was generally found to settle and reproduce on the outer shoot‐end sections of young P. kesiya trees. There was no evidence of preference for any particular levels of the tree canopy. 3 The study suggests that the biological performance and, by implication, the pest status of P. boerneri in young P. kesiya trees can be influenced by external factors, particularly by the within‐tree and seasonal fluctuations in the level of nitrogen in the host trees, total rainfall and canopy structure. 4 These findings are discussed in relation to possible management and control of P. boerneri in Malawi.  相似文献   
966.
The solitary endoparasitoid, Microplitis rufiventris, attacks and can develop in earlier instars of Spodoptera littoralis larvae with preference to third‐instar larvae. We used the last stadium (sixth instar), a stage which is not naturally parasitized. The newly moulted larvae (0–3 h old) of this stadium were more acceptable for parasitization by the wasp females than the older ones (24 h old). Parasitization by M. rufiventris wasp of last instar S. littoralis larvae leads to dose (no. of eggs + parasitoid factors)‐dependent effects which were more pronounced at 20°C than at 27°C. A single oviposition into a sixth instar host larva resulted in normal development of the host. However, superparasitization increased the proportions of developmentally arrested hosts and number of live wasp larvae. Development of supernumerary individuals of the parasitoid in the host larva leads to dose‐related adverse effects on host growth and development. The present study may provide interesting opportunities for studying the physiological bases of host–parasitoid interactions and parasitoid intra‐specific competition in the biological system considered.  相似文献   
967.
968.
Abstract. Strophingia ericae (Curtis) (Homoptera: Psylloidea) takes one or two years to complete its life cycle. In both cases eggs hatch over a prolonged period from midsummer, possibly extending into the following spring at high altitude, and instars overlap in time. Instar III is the predominant overwintering stage in the lowland, annual cycle, whereas in the upland, biennial cycle most first-year nymphs overwinter in instars I and II and most second-year nymphs in instar V. When moved to the laboratory, instars IV and V from a predominantly annual population showed accelerated development in response to elevated temperatures and to long days in both mid-winter and early spring. In the biennial life cycle, short autumn days retard instar V development but the response to photoperiod disappears by the end of winter. Exposure to LD 18 : 6 h retarded development of early instars in the annual population, resulting in an accumulation in instar III. The proportion of overwintering instars I and II rises with increase in altitude and moult to instar III becomes progressively delayed. Nymphs that reach instar III under long daylengths in the year following hatching are channelled towards the biennial cycle. Exposure of a predominantly biennial population to 15 °C and LD 18 : 6 h after midsummer, thus avoiding autumn conditions, promoted the rapid development of overwintered nymphs, switching the cycle from biennial to annual.  相似文献   
969.
Abstract 1. Climate change has been occurring at unprecedented rates and its impacts on biological populations is beginning to be well documented in the literature. For many species, however, long‐term records are not available, and trends have not been documented. 2. Using museum specimens from southern USA, we show that the stream‐dwelling beetle Gyretes sinuatus has shown an 8% increase in body size and change in body shape (fineness ratio) from 1928 to 1988. Any directional morphological change observed over time could be an indicator of a microevolutionary response. 3. During these 60 years, there have also been changes in temperature, precipitation, and location of collection sites. Unlike the global trend, mean annual temperature in the region has decreased, and furthermore, total annual precipitation has increased. By investigating how these various ecological and geographical variables may affect body size and shape, we can examine which pressures may promote larger and/or thinner beetles. 4. Results indicate that mean annual temperature was the most predictive variable for the change in size and shape. We suggest there is an adaptive role for temperature on body size and shape of stream dwelling organisms. 5. We found that museum specimens can be invaluable resources of information when collection date and location information is available. We promote the use of such specimens for future studies of the morphological response to climate change.  相似文献   
970.
Year-class strength in northern populations of smallmouth bass is strongly influenced by winter starvation of young-of-the-year. We examined starvation among young bass under both winter and summer light and temperature conditions. During starvation, body condition declines to a specific level and then the fish dies. Body condition at death is a well defined function of body size that remains relatively constant over a wide range of environmental conditions. Starvation rate varies systematically with body size, temperature, pH and water hardness. Available stored energy increases more rapidly with body size than starvation rate. Therefore, lifetime under starvation conditions tends to increase with increasing body size. The Q10 for starvation rate over the temperature range 2.5-8° C is 2.2. Starvation rate increases as pH declines from 7.0-4.9: the rate at pH 4.9 is ∼ 1.25 times the rate at pH 7 Starvation rate decreases as Ca concentration increases from 1 mgl−1 to 80mgl−1: the rate at 80 mg Ca 1−1 is ∼0.80 times the rate at 1 mgl−1.  相似文献   
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