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921.
922.

Background

This explorative study was undertaken for the first time in Kel village located in the Upper Neelum Valley, Azad Kashmir, Pakistan. The purpose was to document the indigenous knowledge of the native people used in the preparation of herbal medicines.

Methods

To get the data on traditional uses of medicinal plants, 20 informants were interviewed. Quantitative ethnobotanical indices, i.e., use value (UV), relative frequencies of citation (RFC), informant consensus factor (Fic), fidelity level (FL), data matrix ranking (DMR), preference ranking (PR), and jaccard index (JI), were calculated for the recorded medicinal plants.

Results

A total of 50 medicinal plants belonging to 33 families used in 13 disease categories were documented. Leaves were the frequently used plant parts, and decoction was the commonly used method for herbal medicine. Plants with high use value were Berberis lycium (2.05), Impatiens glandulifera (1.95), Artemisia scoparia (1.75), Ageratum conozoides (1.75), and Achillea millefolium (1.7). The highest RFC value was calculated for Berberis lycium (0.75), Cynoglossum lanceolatum (0.65), and Impatiens glandulifera and Achillea millefolium (0.60 each). The maximum informant consensus factor was for urinary system, cardiac diseases, baldness, and abortion and miscarriage (1.00). Berberis lyceum (95%) used in jaundice, hepatitis, typhoid, fever, and tuberculosis disorders. Plants with maximum fidelity level (FL) were Berberis lycium (95%) followed by Dioscorea bulbifera, Impatiens glandulifera, and Artemisia vulgaris (90%). Olea ferruginea was the most multipurpose plant and exports (21.2%) was the leading threat in the area. The pearson correlation coefficient (0.500) showed a positive correlation between the use value and relative frequency of citation.

Conclusion

The present study provides useful information about traditional uses of medicinal plants used by local communities in different ailments. The plants with the highest use values could be employed in pharmacological research and biotechnological approaches in order to achieve adequate revenue. Some of the plants in the study area are facing high threats of becoming rare, and conservation initiatives are needed to conserve them for sustainable management in the region.
  相似文献   
923.
Identifying patients at risk of developing premature coronary artery disease (PCAD) which occurs at age below 45 years old and constitutes approximately 7–10% of coronary artery disease (CAD) worldwide remains a problem. Oxidative stress has been proposed as a crucial step in the early development of PCAD. This study was conducted to determine the oxidative status of PCAD in comparison to CAD patients. PCAD (<45 years old) and CAD (>60 years old) patients were recruited with age-matched controls (n?=?30, each group). DNA damage score, plasma malondialdehyde (MDA) and protein carbonyl content were measured for oxidative damage markers. Antioxidants such as erythrocyte glutathione (GSH), oxidised glutathione (GSSG), and glutathione peroxidase activity (GPx), superoxide dismutase (SOD) and catalase (CAT) were also determined. DNA damage score and protein carbonyl content were significantly higher in both PCAD and CAD when compared to age-matched controls while MDA level was increased only in PCAD (p<.05). In contrast, GSH, GSH/GSSG ratio, α-tocotrienol isomer, and GPx activity were significantly decreased, but only in PCAD when compared to age-matched controls. The decrease in GSH was associated with PCAD (OR?=?0.569 95%CI [0.375???0.864], p?=?.008) and cut-off values of 6.69?μM with areas under the ROC curves (AUROC) 95%CI: 0.88 [0.80–0.96] (sensitivity of 83.3%; specificity of 80%). However, there were no significant differences in SOD and CAT activities in all groups. A higher level of oxidative stress indicated by elevated MDA levels and low levels of GSH, α-tocotrienol and GPx activity in patients below 45 years old may play a role in the development of PCAD and has potential as biomarkers for PCAD.  相似文献   
924.
925.
It is commonly difficult to extract and amplify DNA from herbarium samples as they are old and preserved using different compounds. In addition, such samples are subjected to the accumulation of intrinsically produced plant substances over long periods (up to hundreds of years). DNA extraction from desert flora may pause added difficulties as many contain high levels of secondary metabolites. Herbarium samples from the Biology Department (UAE University) plant collection and fresh plant samples, collected from around Al-Ain (UAE), were used in this study. The three barcode loci for the coding genes matK, rbcL and rpoC1-were amplified. Our results showed that T. terresteris, H. robustum,T. pentandrus and Z. qatarense were amplified using all three primers for both fresh and herbaium samples. Both fresh and herbarium samples of C. comosum, however, were not amplified at all, using the three primers. Herbarium samples from A. javanica, C. imbricatum, T. aucherana and Z. simplex were not amplified with any of the three primers. For fresh samples 90, 90 and 80% of the samples were amplified using matK, rbcL and rpoC1, respectively. In short, fresh samples were significantly better amplified than those from herbarium sources, using the three primers. Both fresh and herbarium samples from one species (C. comosum), however, were not successfully amplified. It is also concluded that the rbcL regions showed real potentials to distinguish the UAE species under investigation into the appropriate family and genus.  相似文献   
926.
In this article, a facile and convenient synthesis of thiazol‐2(3H)‐ylidine derivatives of fatty acid ( 3a – c ) is described. The binding of N′‐(4,5‐dimethyl‐3‐penylthiazol‐2(3H)‐ylidine)octadec‐9‐enehydrazide ( 3a ) with human serum albumin (HSA) is explored using various spectral methods and molecular docking. Fluorescence quenching results show that 3a induces conformational changes in HSA and the polarity around the tryptophan residues is increased. Stern–Volmer quenching plots at different temperatures (298, 305 and 312 K) show that the fluorescence quenching mechanism is static quenching. Synchronous fluorescence, 3D fluorescence spectra, circular dichroism and Fourier transform infrared spectroscopy are used to determine the structural change in HSA on interaction with 3a . Förster resonance energy transfer analysis shows that the binding distance (r0 = 2.78 nm) between HSA (Trp214) and 3a is within the of range 2–8 nm for quenching to occur. The molecular docking study also confirms that 3a is located in subdomain IIA (site I) of HSA and is stabilized by hydrogen bonding and hydrophobic forces.  相似文献   
927.

Background  

Carbonic anhydrase (CA) classically catalyses the reversible hydration of dissolved CO2 to form bicarbonate ions and protons. The twelve active CA isozymes are thought to regulate a variety of cellular functions including several processes in the reproductive systems.  相似文献   
928.
Ras-like small GTP binding proteins regulate a wide variety of intracellular signalling and vesicular trafficking pathways in eukaryotic cells including plant cells. They share a common structure that operates as a molecular switch by cycling between active GTP-bound and inactive GDP-bound conformational states. The active GTP-bound state is regulated by guanine nucleotide exchange factors (GEF), which promote the exchange of GDP for GTP. The inactive GDP-bound state is promoted by GTPase-activating proteins (GAPs) which accelerate GTP hydrolysis by orders of magnitude. Two types of small GTP-binding proteins, ADP-ribosylation factor (Arf) and secretion-associated and Ras-related (Sar), are major regulators of vesicle biogenesis in intracellular traffic and are founding members of a growing family that also includes Arf-related proteins (Arp) and Arf-like (Arl) proteins. The most widely involved small GTPase in vesicular trafficking is probably Arf1, which not only controls assembly of COPI- and AP1, AP3, and AP4/clathrin-coated vesicles but also recruits other proteins to membranes, including some that may be components of further coats. Recent molecular, structural and biochemical studies have provided a wealth of detail of the interactions between Arf and the proteins that regulate its activity as well as providing clues for the types of effector molecules which are controlled by Arf. Sar1 functions as a molecular switch to control the assembly of protein coats (COPII) that direct vesicle budding from ER. The crystallographic analysis of Sar1 reveals a number of structurally unique features that dictate its function in COPII vesicle formation. In this review, I will summarize the current knowledge of Arf and Sar regulation in vesicular trafficking in mammalian and yeast cells and will highlight recent advances in identifying the elements involved in vesicle formation in plant cells. Additionally, I will briefly discuss the similarities and dissimilarities of vesicle traffic in plant, mammalian and yeast cells.  相似文献   
929.
Rainbow trout Oncorhynchus mykiss has a great nutritional value and delicious taste. A 90-days experimental trial was conducted to investigate the effect of dietary leaf extract of neem tree Azadirachta indica as a feeding supplement on the growth performance and proximate composition of O. mykiss. Four experimental diets were designed as T1 (with 5% A. indica leaf extract), T2 (with 7% of A. indica leaf extract), T3 (with 10% A. indica leaf extract), and T4 (control group feed with a regular diet with 0% A. indica leaf extract). The average initial weight of fry 0.4 ± 0.14 g was stocked at 25 fish/tank with two replicates per treatment (4 × 2 = 8). After 90 days of the experimental trial, One-way ANOVA showed significant differences in final body weight, weight gain, specific growth rate, feed conversion ratio, and survival rate among the treatment groups (p < 0.05). The highest final body weight (48.10 g) and weight gain (47.70 g) was observed in T2 with 7% A. indica leaf extract, which was significantly different from the other treatments (p < 0.05). The lowest FCR was recorded in T2 (1.90), which was significantly different compared to other treatment groups (p < 0.05). Inclusion of A. indica leaf extract in formulated feed for rainbow trout had significant effects in the hepatosomatic index, viscerosomatic index and Fulton’s condition factor (p < 0.05), but there was no significant difference in the survival rate of rainbow trout fry treated with different experimental diets (p > 0.05). The phenomenal regression indicates that 7.5% A. indica inclusion is optimum for best growth performance for rainbow trout under a controlled environment. Thus, the present study suggests that the dietary leaf extract has performed an excellent nutritional supplement by enhancing growth performance and health conditions of rainbow trout in the hatchery conditions.  相似文献   
930.
两种种植体系下地下水硝态氮含量变化   总被引:4,自引:0,他引:4  
寿光作为全国闻名的保护地蔬菜产区,过量施肥的现象非常普遍。为了解集约化大棚蔬菜种植区地下水中硝酸盐的含量变化状况,于2003~2005年对寿光市大田(小麦-玉米)、大棚(一年两茬番茄)两种不同的种植体系下农田灌溉水和农村饮用水水井进行了定点跟踪监测。结果表明:大田区地下水中硝态氮的含量随着时间的变化波动很小,农村饮用水中硝态氮含量没有超标现象;随着时间推移,大棚区灌溉水井中硝态氮含量年内(从年初到年末)呈明显的上升趋势,年际间则存在有规律的波动并逐年升高;灌溉水中硝态氮平均含量普遍高于饮用水,浅层地下水明显高于深层地下水;无论大棚区还是大田区,井深不同对地下水的硝态氮含量影响差异很大,浅井中硝态氮的含量明显高于深井。大棚区农村饮用水硝态氮含量超标现象非常普遍,对国家饮用水标准(20mg&#183;L^-1)超标率最高达37.50%,平均为14.06%;对WHO推荐饮用水上限(10mg&#183;L^-1)超标率最高达56.25%,平均为42.19%,硝态氮最高含量45.60mg&#183;L^-1。集约化大棚蔬菜栽培模式已经对农村地下水造成了很大的硝态氮污染,饮用水中较高的硝酸盐含量已经对当地居民的健康构成了潜在的威胁。  相似文献   
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