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81.
Neurochemical Research - Parkinson’s disease (PD) is a neurodegenerative disorder of dopaminergic, noradrenergic, and serotonergic systems, in which dopamine, noradrenaline, and serotonin...  相似文献   
82.
Studies on trichomes micromorphology using Scanning Electron Microscope (SEM) were undertaken in 23 species with one variety under 13 genera of the family Cucurbitaceae (viz., Benincasa hispida (Thunb.) Cogn., Citrullus lanatus (Thunb.) Matsum. & Nakai, Cucumis melo var. agrestis Naudin, Cucumis sativus L., Diplocyclos palmatus (L.) C. Jeffrey, Edgaria dargeelingensis C.B. Clarke, Gynostemma burmanicum King ex Chakr., Gynostemma pentaphyllum (Thunb.) Makino, Gynostemma pubescens (Gagnep.) C.Y. Wu, Hemsleya dipterygia Kuang & A.M. Lu, Lagenaria siceraria (Molina) Standl., Luffa acutangula (L.) Roxb., Luffa cylindrica M. Roem., Luffa echinata Roxb., Melothria heterophylla (Lour.) Cogn., Melothria leucocarpa (Blume) Cogn., Melothria maderspatana (L.) Cogn., Sechium edule (Jacq.) Sw., Thladiantha cordifolia (Blume) Cogn., Trichosanthes cucumerina L., T. cucumerina var. anguina (L.) Haines, Trichosanthes dioica Roxb., Trichosanthes lepiniana (Naudin) Cogn. and T. tricuspidata Lour.). The trichomes in the family Cucurbitaceae vary from unicellular to multicellular, conical to elongated, smooth to ridges, with or without flattened disk at base and cyctolithic appendages, thin to thick walled, curved at apices to blunt. Trichomes micromorphology in the family Cucurbitaceae was found significant taxonomically.  相似文献   
83.
The Indian Ocean (IO) extends over 30% of the global ocean area and is rimmed by 36 littoral and 11 hinterland nations sustaining about 30% of the world's population. The landlocked character of the ocean along its northern boundary and the resultant seasonally reversing wind and sea surface circulation patterns are features unique to the IO. The IO also accounts for 30% of the global coral reef cover, 40,000 km2 of mangroves,some of the world's largest estuaries, and 9 large marine ecosystems. Numerous expeditions and institutional efforts in the last two centuries have contributed greatly to our knowledge of coastal and marine biodiversity within the IO. The current inventory, as seen from the Ocean Biogeographic Information System, stands at 34,989 species, but the status of knowledge is not uniform among countries. Lack of human, institutional, and technical capabilities in some IO countries is the main cause for the heterogeneous level of growth in our understanding of the biodiversity of the IO. The gaps in knowledge extend to several smaller taxa and to large parts of the shelf and deep-sea ecosystems, including seamounts. Habitat loss, uncontrolled developmental activities in the coastal zone, over extraction of resources, and coastal pollution are serious constraints on maintenance of highly diverse biota, especially in countries like those of the IO, where environmental regulations are weak.  相似文献   
84.
The majority of patients with the autosomal dominant disorder familial hypercholesterolemia (FH) carry novel mutations in the low density lipoprotein receptor (LDLR) that is involved in cholesterol regulation. In different populations the spectrum of mutations identified is quite different and to date there have been only a few reports of the spectrum of mutations in FH patients from Pakistan. In order to identify the causative LDLR variants the gene was sequenced in a Pakistani FH family, while high resolution melting analysis followed by sequencing was performed in a panel of 27 unrelated sporadic hypercholesterolemia patients. In the family a novel missense variant (c.1916T > G, p.(V639G)) in exon 13 of LDLR was identified in the proband. The segregation of the identified nucleotide change in the family and carrier status screening in a group of 100 healthy subjects was done using restriction fragment length polymorphism analysis. All affected members of the FH family carried the variant and none of the non-affected members nor any of the healthy subjects. In one of the sporadic cases, two sequence changes were detected in exon 9, one of these was a recurrent missense variant (c.1211C > T; p.T404I), while the other was a novel substitution mutation (c.1214 A > C; N405T). In order to define the allelic status of this double heterozygous individual, PCR amplified fragments were cloned and sequenced, which identified that both changes occurred on the same allele. In silico tools (PolyPhen and SIFT) were used to predict the effect of the variants on the protein structure, which predicted both of these variants to have deleterious effect. These findings support the view that there will be a novel spectrum of mutations causing FH in patients with hypercholesterolaemia from Pakistan.  相似文献   
85.
Adsorption behaviour of Ni(II), Zn(II), Cd(II) and Cr(VI) on untreated and phosphate-treated rice husk (PRH) showed that adsorption of Ni(II) and Cd(II) was greater when PRH was used as an adsorbent. Sorption of Cd(II) was dependent on contact time, concentration, temperature, adsorbent doses and pH of the solution. The Langmuir constants and thermodynamic parameters have been calculated at different temperatures. It was found that recovery of Cd(II) from synthetic wastewater by column operation was better than a batch process.  相似文献   
86.
This article first presents an overview of published literature documenting the role of the scavenger receptor CD36 in activation of brain microglia with reference to brain pathologies such as Alzheimer's and malaria. Second, the possibility that CD36 may play a role in brain FA metabolism is discussed. Long-chain polyunsaturated fatty acids (PUFAs) are important for brain function and are mostly derived from the plasma. Based on its role in facilitating FA uptake in several tissues and cell types, CD36 expressed on microvascular endothelial cells in the brain may facilitate local uptake of PUFAs. Alternatively, CD36 may influence brain FA supply indirectly via impacting utilization of dietary FA or their metabolism in tissues such as the liver. We examined the possibility that CD36 expression impacts brain function by evaluating the behavior of CD36 null mice using a battery of standard tests. Our data indicate that CD36 deficient mice have normal patterns of activity, anxiety and exploration of novel environments. However they appear to have a significant impairment in learning ability. These findings could provide a new perspective regarding the regulation of brain lipid metabolism.  相似文献   
87.
The deciduous habit and tendency to produce flowers prior to developing leaves, and a predominantly dioecious system of breeding in the genus Commiphora leads to difficulties in its taxonomic identification at species level. The characteristics of easy amplification by universal primer, shorter length and higher discrimination power at the species level makes the internal transcribed spacer (ITS) sequence of nuclear ribosomal DNA (nrDNA) to a smart gene for generating species-specific phylogenetic inferences in most of the plants groups. The present study deals the ITS sequence of nrDNA based molecular genotyping of seven species of the genus Commiphora of Saudi Arabia. The molecular phylogenetic analysis of ITS sequences of nrDNA of Commiphora species distributed in Saudi Arabia reveals the the occurrence of C. madagascariens in Saudi Arabia.  相似文献   
88.
Plasma fatty acids from renal and hepatic veins, and arterialized hand vein obtained in 20 subjects before and after insulin infusion were separated by reversed-phase high-performance liquid chromatography following phenacyl esterification. Separation and quantification over the range 1.0–100 nmol per injection of nine fatty acids was achieved within 60 min using [2H31]palmitic acid as internal standard. Analytical recoveries were greater than 90% and the intra- and inter-assay coefficients of variation were less than 2.5 and 4.0%, respectively. Following insulin infusion, net splanchnic uptake of total fatty acids decreased from 3.0±0.3 to 1.0±0.1 μmol/kg min (p<0.01), whereas net renal balance remained neutral (−0.04±0.04 vs. −0.06±0.03 μmol/kg min, p=N.S.). Individual fatty acid balance varied from a low of 0.012±0.005 (myristic acid) to a high of 0.95±0.08 (oleic acid) μmol/kg min across the splanchnic tissues and from 0.005±0.002 (stearic acid) to 0.21±0.1 (oleic acid) μmol/kg min across the kidney. There is a substantial diversity in changes in plasma concentration and regional balance of individual fatty acid during short-term fasting and hyperinsulinemia. This method is simple, accurate, and can be applied to assess individual fatty acid metabolism in vivo.  相似文献   
89.
Gamma-vinyl GABA (GVG, Vigabatrin), an irreversible inhibitor of GABA transaminase (GABA-T) that inhibits cocaine-induced place preference and self administration has been proposed as a treatment for cocaine addiction. It was therefore important to assess if there was an enhanced toxicity from the combination of GVG with cocaine. No mortality was observed with administration of GVG (60 mg/kg i.v.) alone (n=8) or in combination (n=6) with cocaine (5 mg/kg i.v.). Cocaine-induced EKG alterations were not affected by GVG pretreatment. Plasma alanine amino transferase activity was reduced by GVG treatment and this was not further modified by cocaine administration. These results suggest that acute co-administration of GVG and cocaine does not result in immediate cardiovascular or hepatic toxicity of sufficient significance, to preclude further clinical trials.  相似文献   
90.
Tea is one of the top beverages used around the world every day, which contains a high amount of polyphenols and antioxidants. The main aim of this research is to quantify some marketed black tea (Rabea, Lipton, Alkbous, Green gold and Haritham) for phenolic contents and antioxidant potential evaluation by ultrasound solvent extraction and was compared with conventional extraction. Ultrasonic extraction was optimized by considering frequencies (26 kHz, 40 kHz), temperature (30, 40 and 50 °C), and power (30, 40 and 50%) at a fixed time of 30 min. In both the ultrasonic frequencies, 40 °C temperature and 40% power combination exhibited highest cumulative yield (mg/100 g DW), total phenolic content (mg gallic acid/g DW), flavonoids (mg/g DW) and DPPH radical scavenging activity (%) in all branded tea. Within each brand of tea, at any temperature-power combination at particular frequency results were not significantly different. But, at a similar condition of temperature power results were found significantly different between two frequencies. Furthermore, ultrasonic extraction process was analyzed thermodynamically by selecting some basic parameters. Thermodynamics results showed the extraction process was feasible, spontaneous and irreversible. Also, 26 kHz ultrasonic probe is more appropriate for the extraction purpose and thermodynamically more acceptable as compared to 40 kHz ultrasonic bath. Moreover, Haritham was selected as the best tea brand due to its high polyphenol contents and antioxidant potential.  相似文献   
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