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71.
The present study examined the effect of salicylic acid (SA) pre-treatment on soybean seedlings exposed to cadmium and/or UV-B stress. Dry mass, pigment content, net photosynthetic rate (PN), stomatal conductance (gs), and transpiration rate (E) were decreased by the Cd and/or UV-B stress. SA alleviated the adverse effects of Cd and/or UV-B on growth, pigment content, PN, and gs, but did not mitigate the inhibitory effect of Cd/UV-B on E, or that of Cd on chlorophyll fluorescence parameters. Cd and/or UV-B induced oxidative stress and increased lipid peroxidation that was significantly decreased by SA pre-treatment. The Cd and/or UV-B increased superoxide dismutase (SOD) activity, decreased peroxidase (POD) activity, and catalase (CAT) activity was mostly unaltered. SA might act as one of the potential antioxidants as well as a stabilizer of membrane integrity to improve plant resistance to the Cd and/or UV-B stress.  相似文献   
72.
Diabetic nephropathy (DN) is one of the foremost causes of renal failure and a primary cause of diabetes mellitus related death. Previously, we have reported that aqueous extract of Enicostemma littorale has potential antidiabetic activity. In the present study, we have investigated the effect of aqueous extract of E. littorale 1 g/kg, p.o. and swertiamarin 50 mg/kg, p.o. daily for 3 weeks in type 1 DN complications in SD rats. DN was assessed by serum urea, creatinine, lipid profile and water intake levels. Treatment with aqueous extract of E. littorale and swertiamarin significantly decreased serum urea and creatinine and other parameters associated with the development of DN in type 1 diabetic rats. We have also found considerable improvement in histology of glomerular function of aqueous extract of E. littorale and swertiamarin-treated animals.  相似文献   
73.
A unique cycle of female form alternation has been revealed in an experimental population of Orconectes limosus during a year-long observation. Significant cyclic changes observed in chelae length, width, and robustness, as well as in abdomen width, demonstrated a form alternation similar to that in conspecific males. Small females alternate between sexually active and sexually inactive forms with a short time interval between successive molts as well as different growth patterns of some body parts. Form alternation efficiently produces larger chelae, abdomen, and body dimensions, especially the molt to form I (sexually active). Larger females that undergo only a single annual molt do not alter between forms and are sexually active. They grow slowly and lose chelae robustness. The cycle of form alternation, consisting of two molts per year, may facilitate the effective utilization of resources to increase the size of body parts important to survival and reproduction.  相似文献   
74.
To restore deteriorated lake ecosystems, it is important to identify environmental factors that influence submerged macrophyte communities. While sediment is a critical environmental factor for submerged macrophytes and many studies have examined effects of sediment type on the growth of individual submerged macrophytes, very few have tested how sediment type affects the growth and species composition of submerged macrophyte communities. We constructed submerged macrophyte communities containing four co-occurring submerged macrophytes (Hydrilla verticillata, Myriophyllum spicatum, Ceratophyllum demersum and Chara fragilis) and subjected them to three sediment treatments, i.e., clay, a mixture of clay and quartz sand at a volume ratio of 1:1 and a mixture at a volume ratio of 1:4. Compared to the clay, the 1:1 mixture treatment greatly increased overall biomass, number of shoot nodes and shoot length of the community, but decreased its diversity. This was because it substantially promoted the growth of H. verticillata within the community, making it the most abundant species in the mixture sediment, but decreased that of M. spicatum and C. demersum. The sediment type had no significant effects on the growth of C. fragilis. As a primary nutrient source for plant growth, sediment type can have differential effects on various submerged macrophyte species and 1:1 mixture treatment could enhance the performance of the communities, increasing the overall biomass, number of shoot nodes and shoot length by 39.03%, 150.13% and 9.94%, respectively, compared to the clay treatment. Thus, measures should be taken to mediate the sediment condition to restore submerged macrophyte communities with different dominant species.  相似文献   
75.
We report the purification and crystallization of phosphoglycerate kinase from Thermus caldophilus (Tca). The enzyme crystallizes in the P2(1)2(1)2(1) space group (cell dimensions a = 65.1, b = 71.3, c = 80.2 A), with one molecule in the asymmetric unit. A complete set of diffraction data was collected from an orthorhombic crystal up to 1.8 A resolution.  相似文献   
76.

The Balkan chamois (Rupicapra rupicapra balcanica) is widespread on the Balkan Peninsula, along mountain massifs from Croatia in the north to Greece in the south and Bulgaria in the east. Knowledge on the genetic structure of Balkan chamois populations is limited and restricted to local studies. Therefore, the main objective of this study was to use nuclear (16 microsatellites) and mitochondrial (partial 376 base pairs control region) markers to investigate the genetic structure of this chamois subspecies throughout its distribution range and to obtain information on the degree of connectivity of the different (sub)populations. We extracted DNA from bone, dried skin and muscle tissue and successfully genotyped 92 individuals of Balkan chamois and sequenced the partial control region in 44 individuals. The Bayesian analysis suggested 3 genetic clusters and assigned individuals from Serbia and Bulgaria to two separate clusters, while individuals from the other countries belonged to the same cluster. Thirty new haplotypes were obtained from partial mitochondrial DNA sequences, with private haplotypes in all analyzed populations and only two haplotypes shared among populations, indicating the possibility of past translocations. The subspecies genetic composition presented here provides the necessary starting point to assess the conservation status of the Balkan chamois and allows the development of conservation strategies necessary for its sustainable management and conservation.

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77.
Ye  Jiali  Bu  Yaning  He  Mengting  Wu  Yongfeng  Yang  Xuetong  Zhang  Lingli  Song  Xiyue 《Plant Growth Regulation》2022,98(1):77-89
Plant Growth Regulation - Invertase (INV, EC3.2.1.26) is involved in carbohydrate partitioning by irreversibly hydrolyzing sucrose into fructose and glucose. INV genes that are specifically...  相似文献   
78.
79.
The effects of intracerebroventricular (i.c.v.) administration of calcitonin and PGE2 on intestinal motility and body temperature were examined in conscious rats chronically fitted with intraparietal electrodes in the small intestine, a cannula in a cerebral lateral ventricle and a subcutaneous thermistor probe. Both calcitonin and PGE2 restored the fasted pattern of intestinal motility in fed rats and induced an increase in body temperature. Indomethacin, an inhibitor of the cyclooxygenase with calcium antagonistic properties, and TMB-8, an intracellular calcium antagonist, blocked the effects of calcitonin on intestinal motility and body temperature. Piroxicam, an inhibitor of the cyclooxygenase which does not affect calcium uptake blocked the thermic but not the intestinal effects of calcitonin. TMB-8 but not indomethacin or piroxicam partially blocked the effects of PGE2 on both intestinal motility and body temperature. It is concluded that the central hyperthermic effect of calcitonin is mediated through the formation and the release of prostaglandins whereas the central action of calcitonin on digestive motility results from intracerebral effects on calcium fluxes.  相似文献   
80.
作为病毒诊断实验室必备的一种手段 ,PCR相关的病毒分子生物学诊断技术准确、快速、敏感、简便 ,对指导临床治疗十分重要。本文对近年来 PCR技术方法学研究与应用研究及生物传感器诊断病毒等方面的一些进展进行了综述  相似文献   
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