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991.
Journal of Plant Growth Regulation - Citrus holds the key position in horticulture sector of Pakistan in terms of area and production. Kinnow is considered as the trademark of Pakistan’s...  相似文献   
992.
Journal of Plant Growth Regulation - Heat stress is a major detriment to crop growth and yield under the current patterns of climate change. Two independent experiments of camelina and canola were...  相似文献   
993.
Amylases are biologically active enzymes that can hydrolyze starch to produce dextrin, glucose, maltose, and oligosaccharides. The amylases contribute approximately 30% to the global industrial enzyme market. The globally produced amylases are widely used in textile, biofuel, starch processing, food, bioremediation of environmental pollutants, pulp, and paper, clinical, and fermentation industries. The purpose of this review article is to summarize recent trends and aspects of α-amylases, classification, microbial production sources, biosynthesis and production methods, and its broad-spectrum applications for industrial purposes, which will depict the latest trends in α-amylases production. In the present article, we have comprehensively compared the biodiversity of α-amylases in different model organisms ranging from archaea to eukaryotes using in silico structural analysis tools. The detailed comparative analysis: regarding their structure, function, cofactor, signal peptide, and catalytic domain along with their catalytic residues of α-amylases in 16 model organisms were discussed in this paper. The comparative studies on alpha (α) amylases' secondary and tertiary structures, multiple sequence alignment, transmembrane helices, physiochemical properties, and their phylogenetic analysis in model organisms were briefly studied. This review has documented the recent trends and future perspectives of industrially important novel thermophilic α-amylases. In conclusion, this review sheds light on the current understanding and prospects of α-amylase research, highlighting its importance as a versatile enzyme with numerous applications and emphasizing the need for further exploration and innovation in this field.  相似文献   
994.
Even though Helicobacter pylori infection was the most causative factor of gastric cancer, numerous in vivo studies failed to induce gastric cancer using Hpylori infection only. The utilization of established animal studies in cancer research is crucial as they aim to investigate the coincidental association between suspected oncogenes and pathogenesis as well as generate models for the development and testing of potential treatments. The methods to establish gastric cancer using infected animal models remain limited, diverse in methods, and showed different results. This study investigates the differences in animal models, which highlight different pathological results in gaster by literature research. Electronic databases searched were performed in PubMed, Science Direct, and Cochrane, without a period filter. A total of 135 articles were used in this study after a full-text assessment was conducted. The most frequent animal models used for gastric cancer were Mice, while Mongolian gerbils and Transgenic mice were the most susceptible model for gastric cancer associated with Hpylori infection. Additionally, transgenic mice showed that the susceptibility to gastric cancer progression was due to genetic and epigenetic factors. These studies showed that in Mongolian gerbil models, Hpylori could function as a single agent to trigger stomach cancer. However, most gastric cancer susceptibilities were not solely relying on Hpylori infection, and numerous factors are involved in cancer progression. Further study using Mongolian gerbils and Transgenic mice is crucial to conduct and establish the best models for gastric cancer associated Hpylori.  相似文献   
995.

To evaluate the effects of nitrogen (N) and irrigation coupling on the soil N distribution, plant N utilization, and fruit yield of rabbiteye blueberries (Vaccinium virgatum), a field experiment was designed using two factors (water and fertilizer application) with four levels of irrigation and three levels of fertilization, and a control. Under the different water and fertilizer combinations, N primarily accumulated in the leaves. Irrigation and N application within appropriate ranges (pure N ≤ 29 g/plant and irrigation volume ≤ 2.5 L/plant) significantly improved the blueberry fruit yield. Increases in water and N within these ranges promoted the effective accumulation of N in various organs and the absorption and utilization of N in the plants, which ultimately promoted blueberry yield. With increased N application rate, the nitrate N content of the 0–20 cm and 20–50 cm soil layers increased. With increased irrigation volume, the nitrate N content of the 0–20 cm soil layer decreased, while the nitrate content in the 20–50 cm soil layer increased. Low N and moderate water treatments resulted in high fruit yields and reduced nitrate N retention in the soil. Under these conditions, the economic input-output ratio was high and the soil N accumulation was low, and thus the economic and ecological benefits were maximized.

  相似文献   
996.
BackgroundGlaucoma is a neurodegenerative ophthalmic disorder and is considered among the leading causes of irreversible blindness. Primary open-angle glaucoma (POAG) is the most common type of glaucoma that affects after 30 years of life, progressing slowly, and manifests as decreased visual acuity leading to blindness if not treated. POAG is genetically heterogeneous, inherited most commonly in autosomal dominant mode. Several genes have been reported for POAG with myocilin (Myoc) being most common. The present study has been conducted to screen 25 POAG families with 2 or more affected members for their association with Myoc and CYP1B1 (the most common gene in primary congenital glaucoma).MethodsAfter approval from Institutional Ethical Review Committee (ERC), 25 POAG families were enrolled from the southern province (Sindh) of Pakistan. Written informed consent was obtained from all participating individuals and diagnosis was confirmed by consultant ophthalmologists using various instruments and means. Venous blood was obtained from affected individuals and their normal family members for DNA extraction and subsequent analysis.ResultsAll samples were initially screened for the Myoc gene followed by CYP1B1. Screening for Myoc revealed one previously reported variant c.144G>T in POAG-06 whereas screening for CYP1B1 in all 25 families showed a novel variant c.649G>A in POAG-02. The pathogenicity of the novel variant was confirmed using various bioinformatics tools.ConclusionThis is the first report of any POAG family found associated with a novel variant in CYP1B1 from the southern province of Pakistan whereas one family found associated with a reported variant in Myoc. The remaining 23 POAG families did not found to be associated with either Myoc or CYP1B1 indicating genetic heterogeneity of the population in this part of the world.  相似文献   
997.
Nanotechnology is perhaps the most widely explored scientific domain in the current era. With the advent of NPs, revolutionary changes have been observed in various scientific disciplines. Among the NPs, ZnO-NPs are the center of contemplation owing to their biocompatible nature. These nanoparticles have been prepared using a number of techniques; however, biological methods are among the most popular synthesis approaches. The current research therefore reports the phyto-fabrication of ZnO-NPs mediated by Delphinium uncinatum root extract. The resulting NPs were subjected to standard characterization methods such fourier transformed infrared spectroscopy, X-ray diffraction and transmission electron microscopy. The resulting NPs are exploited to their possible antioxidant, antimicrobial, antidiabetic, cytotoxic, anti-inflammatory and anti-ageing potency. FTIR confirmed the capping of ZnO-NPs by a variety of phytochemicals. ZnO-NPs average size was approximately 30 nm. ZnO-NPs exhibited substantial bio-potency and proved to be highly biocompatible even at higher concentrations. ZnO-NPs revealed strong antimicrobial potency for Pseudomonas aeruginosa proving to be the most susceptible strain showing inhibition of 16 ± 0.98. ZnO-NPs also showed dose dependent antidiabetic and cytotoxic potential. COX-1, COX-2, 15-LOX and sPLA2 were efficiently inhibited upon exposure to ZnO-NPs confirming the anti-inflammatory potential of ZnO-NPs. Similarly, ZnO-NPs also revealed considerable anti-aging potential. With such diverse biological potentials, ZnO-NPs can prove to be a potent weapon against a plethora of diseases; however, further study is necessary in order to discover the precise mechanism that is responsible for the biological potency of these NPs.  相似文献   
998.
999.
Length-weight relationships (LWRs) were estimated for seven small indigenous cyprinid fish species including Securicula gora, Osteobrama cotio, Esomus lineatus, Pethia gelius, Megarasbora elonga, Gonialosa manmina and Glossogobius aureus occurring in the Kaptai Lake, Bangladesh. Fish were collected monthly basis between March and October, 2018 from fishermen catches landed in the fish landing center, Rangamati. Fishermen operated lift net (mesh size < 0.5 cm), punti net (mesh size < 0.5 cm) and cast net (mesh size < 0.5 cm) for capturing these species. The value of exponent b ranged between 2.769 and 3.212 and regression parameter r2 was between 0.926 and 0.992. New maximum total lengths were recorded for E. lineatus and G. manmina in this study.  相似文献   
1000.
Canopy bridges are increasingly used to reduce fragmentation in tropical habitats yet monitoring of their impact on the behavior of primates remains limited. The Javan slow loris (Nycticebus javanicus) is endemic to Java, Indonesia, where the species most often occurs in human-dominated, highly patchy landscapes. Slow lorises cannot leap, are highly arboreally adapted, and are vulnerable on the ground. To increase arboreal connectivity, as part of a long-term conservation project in Cipaganti, West Java, we built and monitored seven slow lorises bridges of two types—waterline or rubber—and monitored their use by seven adult individuals from 2016 to 2017. Motion triggered camera traps collected data for 195 ± standard deviation (SD) 85 days on each bridge. We collected 341.76 hr (179.67 hr before and 162.09 hr after the installation of bridges) of behavioral and home range data via instantaneous sampling every 5 min, and terrestrial behavior (distance and duration of time spent on the ground) via all occurrences sampling. We found that slow lorises used bridges on average 12.9 ± SD 9.7 days after their installment mainly for traveling. Slow lorises showed a trend toward an increase in their home range size (2.57 ha before, 4.11 ha after; p = 0.063) and reduced ground use (5.98 s/hr before, 0.43 s/hr; p = 0.063) after implementation of bridges. Although the number of feeding trees did not change, new feeding trees were included in the home range, and the proportion of data points spent traveling and exploring significantly decreased (p = 0.018). Waterline bridges serve a purpose to irrigate the crops of local farmers who thus help to maintain the bridges, and also ascribe value to the presence of slow lorises. Other endemic mammal species also used the bridges. We advocate the use and monitoring of artificial canopy bridges as an important supplement for habitat connectivity in conservation interventions.  相似文献   
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