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271.
The coconut palm is an important crop in the sub arid coastal plain of Dhofar, Oman, for the high demand for its nut water and its use as ornamental plant. Damage of coconut fruits by the eriophyid mite Aceria guerreronis Keifer was first reported in that region in the late 1980s, but background information about the ecology of the pest in Oman was missing. Four surveys were conducted in different seasons from 2008 to 2009, to assess the distribution and prevalence of the coconut mite and its damage as well as the presence of natural enemies. Infestation by the coconut mite was conspicuous on most (99.7 %) palm trees, with 82.5 % damaged fruits. The average (±SE) density of coconut mites per fruit was 750 ± 56; this level of infestation led to the incidence of over 25 % of surface damage on more than half of the fruits. The mite appeared more abundant at the end of the cold season through the summer. No significant differences were observed between infestation levels on local varieties, hybrids and on dwarf varieties. Neoseiulus paspalivorus (De Leon), Cydnoseius negevi (Swirski & Amitai) and Amblyseius largoensis (Muma) were the predatory mites found under the bracts of over 30 % of the coconut fruits and on 68 % of the coconut trees. Considering all sampling dates and all varieties together, average (± SE) phytoseiid density was 1.4 ± 1.19 per fruit. Other mites found in the same habitat as A. guerreronis included the tarsonemids Steneotarsonemus furcatus De Leon and Nasutitarsonemus omani Lofego & Moraes. The pathogenic fungus Hirsutella thompsonii Fisher was rarely found infecting the coconut mite in Dhofar. Other fungal pathogens, namely Cordyceps sp. and Simplicillium sp., were more prevalent.  相似文献   
272.
Abstract

Allelopathy is a biological process in which plants synthesize allelochemicals that affect the physiological properties, development and survival of other plants. Experiments were conducted to investigate the allelopathic effect of Rhazya stricta leaf extracts on the germination, early seedling growth and metabolism of Salsola villosa. Aqueous extracts (10, 30 and 50 g/ L) decreased germination and growth by reducing the synthesis of chlorophyll pigments. Leachate treatments induced the antioxidant system by upregulating antioxidant enzyme activities. Additionally, the activities of phenylalanine ammonia lyase and indole acetic acid oxidase were stimulated by exposure to leachate. R. stricta leachates reduced the content of polyunsaturated membrane fatty acids with a concomitant increase in the saturated ones. Unsaturated fatty acids were reduced with the increased concentration of leachate. Phospholipids were also reduced due to leachate, thereby affecting membrane functioning considerably. Aqueous extracts from the leaves of R. stricta restrict the growth and metabolism of S. villosa by hampering membrane functioning and photosynthetic capacity.  相似文献   
273.
Objective: To compare the oral health‐related quality of life (OHRQoL) between patients with both maxillary and mandibular complete denture and those with either the maxillary or the mandibular complete denture. Background: Satisfaction of denture wearers can be estimated using the OHRQoL questionnaires like the OHIP‐EDENT and the Geriatric Oral Health Assessment Index (GOHAI). Methods: Two questionnaires were used to compare the OHRQoL between edentulous patients who had conventional removable complete denture on both jaws and those who had on either one of the jaws. Result: The age of the participants ranged from 42 to 75 years, with the mean age of 58 ± 8.12 years. The mean OHIP‐EDENT scores were significantly high among those who wore conventional dentures in both jaws (54.12 ± 5.21), compared with the participants who only had denture either on upper or lower jaw (46.52 ± 7.35). It was noticed that the mean GOHAI score was significantly lower (p < 0.05) among participants who had conventional denture on both upper and lower jaw (28.25 ± 3.67), as compared to those who had conventional denture only on one arch (35.12 ± 2.11). Conclusion: Patients with complete dentures in both jaw (Group I) were less satisfied than patients with single complete denture (Group II). The result obtained in this study shows dissatisfaction with conventional dentures among edentulous patients.  相似文献   
274.
275.
Kuhl’s pipistrelle is found from Europe and North Africa all of the way to Asia, yet studies have thus far concentrated on the western limit of its distribution. Here we form a multi-marker picture of the diversity of Kuhl’s pipistrelle at a mid point in the Arabian peninsula in an attempt to redress the western sampling bias and to represent a region from which no genetic data has thus far been presented for this species. The three Arabian Cytochrome b haplotypes showed a clear divergence of 19 substitutions from those found in either Europe or North Africa. Molecular dating suggests the Arabian population split from the remaining Kuhl’s somewhere between 0.7 and 1.7 million years before present around the time of a series of aridification events across northern Africa. Well supported lineages within Arabia are typical of that which may be seen after an expansion from multiple Pleistocene refugia, but may also reflect the loss of intermediate haplotypes during historical population fluctuations. A long-term population contraction coincides with climatic changes towards those conditions more typical of contemporary Arabia.  相似文献   
276.
Pre-Pottery Neolithic assemblages are best known from the fertile areas of the Mediterranean Levant. The archaeological site of Jebel Qattar 101 (JQ-101), at Jubbah in the southern part of the Nefud Desert of northern Saudi Arabia, contains a large collection of stone tools, adjacent to an Early Holocene palaeolake. The stone tool assemblage contains lithic types, including El-Khiam and Helwan projectile points, which are similar to those recorded in Pre-Pottery Neolithic A and Pre-Pottery Neolithic B assemblages in the Fertile Crescent. Jebel Qattar lies ∼500 kilometres outside the previously identified geographic range of Pre-Pottery Neolithic cultures. Technological analysis of the typologically diagnostic Jebel Qattar 101 projectile points indicates a unique strategy to manufacture the final forms, thereby raising the possibility of either direct migration of Levantine groups or the acculturation of mobile communities in Arabia. The discovery of the Early Holocene site of Jebel Qattar suggests that our view of the geographic distribution and character of Pre-Pottery Neolithic cultures may be in need of revision.  相似文献   
277.
Diabetes mellitus (DM) is a chronic disease that is characterized by deteriorating glycemic control. The disease is known to be caused by imbalance between reactive oxygen species (ROS) and antioxidant defense systems. Hyperglycemia is commonly observed in a wide variety of diseases, including cancer. Although, therapy against glycemic control, is used in all these diseases, the diabetic cancer patients are on additional therapy with anticancer drugs. The objective of present study was to study if Glucophage (metformin), a very popular antidiabetic agent can avert the mutagenicity and lipid peroxidation caused by adriamycin (ADR), which is a commonly used cytotoxic drug. The experimental protocol included oral treatment of mice with different doses (62.5, 125 and 250 mg/kg day) of metformin for 7 days. Some mice in each group were injected i.p. with ADR (15 mg/kg). In each case animals were killed, 30 or 24, 48 and 72 h after the last treatment and femurs were excised for cytological studies by micronucleus test. Additional experiments on estimation of glutathione (GSH) and malondialdehyde (MDA) were undertaken in blood and serum, respectively. Twenty-four hour after the treatment, blood from each mouse was collected from heart and preserved for analysis. The results obtained revealed that pretreatment with metformin: (i) reduced the ADR-induced frequency of micronuclei without any alteration in its cytotoxicity and (ii) protected against the ADR-induced increase and decrease of MDA and GSH, respectively. The exact mechanism of action is not known, however, the inhibition of ADR-induced clastogenicity and lipid peroxidation by metformin may be attributed to the antioxidant action of the latter. Our results demonstrate that metformin might be useful to avert secondary tumor risk by decreasing the accumulation of free radicals and inhibition of mutagenicity.  相似文献   
278.
The aim was to create a Modern Standard Arabic SCAT5 version for different Arabic dialects. This translation and cross-cultural adaptation was performed in eight stages: initial translations, reconciliation of translations and cultural adaptation, back translation, appraisal of back translations, validation of the translation, review and adjustment by reconciliation committee, pretesting in 12 football players and document finalisation. As an alternative to the problematic Months In Reverse Order Test (MIROT) in Arabic, the Serial 3s test (32 Arabic and 30 English participants), the Days of the Week Backwards test (DWBT), and the ‘Adding Serial 3s’ test were tested (30 English and 30 Arabic participants) for accuracy, difficulty and time of completion. The Arabic SCAT5 was similar and comparable to the original English version (7-point Likert scales =< 2). Testing of the pre-final version of the Arabic SCAT5 took 20.4 (SD 3.4) and 17.7 (SD 3.0) minutes respectively to complete and was found acceptable in terms of clarity, understandability, grammatical correctness and coherence. The Arabic Serial 3s test (subtraction version) was unsuitable due to high completion time, low pass rate and high difficulty perception [time = 47.2 (SD 28.0) s; accuracy = 55.2%; difficulty = 3.2 (SD 1.1)]. The Arabic DWBT was too fast and undemanding for concentration testing [time = 4.6 (SD 1.5) s; accuracy = 90%; difficulty = 1.1 (SD 0.3)]. The Adding Serial 3s tests produced similar completion times [18.4 (SD 6.8) vs. 21.1 (SD 5.3), p = 0.088], accuracy (100%) and self-rated difficulty [English = 2.0 (SD 0.7) vs. Arabic-speaking participants = 2.1 (SD 0.8), p = 0.512] and was therefore adopted to replace the MIROT. This culturally adapted Arabic-SCAT5 questionnaire is the first concussion assessment tool available for Arabic-speaking healthcare providers and athletes. Sport Concussion Assessment Tool 5 (SCAT5). Biol Sport. 2021;38(1):129–144.  相似文献   
279.
The microbial community associated with a marine sponge (Haliclona sp.) collected from Tateyama city, Japan was studied using 16S rRNA gene clone libraries. Two DNA templates were prepared using methods recommended for Gram-positive and Gram-negative bacteria in the Qiagen kit manual. From each DNA template, two 16S rRNA genes were PCR amplified, using the combination of universal bacterial primer 27f and primers 1385r and 1492r, respectively. A total of 347 clones were sequenced and compared with those available in DNA data banks. These sequences were members of ten bacterial phyla. Interestingly, more than 30 % of the clones represent novel sequences. A comparison of these sequences with sequences in a library prepared from DNA extracted from the surrounding water shows minimum DNA contamination. Taxonomically, the highest diversity was detected in the clone library prepared using a combination of primers 27f and 1492r and DNA isolated using the Gram-positive bacteria protocol. The potential of Haliclona sp.-associated bacteria to produce secondary metabolites was studied by cloning and sequencing the polyketide synthase (PKS, type 1) gene using the same DNA samples. Analysis of partial sequences derived from the sponge metagenome revealed 27 unique ketosynthase domains of PKS type I. This study suggests strongly that this Haliclona sp. plays host to diverse novel bacteria with a potential to produce novel polyketides.  相似文献   
280.
This study investigated the hepatoprotective effects of ethanolic Andrographis paniculata leaf extract (ELAP) on thioacetamide-induced hepatotoxicity in rats. An acute toxicity study proved that ELAP is not toxic in rats. To examine the effects of ELAP in vivo, male Sprague Dawley rats were given intraperitoneal injections of vehicle 10% Tween-20, 5 mL/kg (normal control) or 200 mg/kg TAA thioacetamide (to induce liver cirrhosis) three times per week. Three additional groups were treated with thioacetamide plus daily oral silymarin (50 mg/kg) or ELAP (250 or 500 mg/kg). Liver injury was assessed using biochemical tests, macroscopic and microscopic tissue analysis, histopathology, and immunohistochemistry. In addition, HepG2 and WRL-68 cells were treated in vitro with ELAP fractions to test cytotoxicity. Rats treated with ELAP exhibited significantly lower liver/body weight ratios and smoother, more normal liver surfaces compared with the cirrhosis group. Histopathology using Hematoxylin and Eosin along with Masson’s Trichrome stain showed minimal disruption of hepatic cellular structure, minor fibrotic septa, a low degree of lymphocyte infiltration, and minimal collagen deposition after ELAP treatment. Immunohistochemistry indicated that ELAP induced down regulation of proliferating cell nuclear antigen. Also, hepatic antioxidant enzymes and oxidative stress parameters in ELAP-treated rats were comparable to silymarin-treated rats. ELAP administration reduced levels of altered serum liver biomarkers. ELAP fractions were non-cytotoxic to WRL-68 cells, but possessed anti-proliferative activity on HepG2 cells, which was confirmed by a significant elevation of lactate dehydrogenase, reactive oxygen species, cell membrane permeability, cytochrome c, and caspase-8,-9, and, -3/7 activity in HepG2 cells. A reduction of mitochondrial membrane potential was also detected in ELAP-treated HepG2 cells. The hepatoprotective effect of 500 mg/kg of ELAP is proposed to result from the reduction of thioacetamide-induced toxicity, normalizing reactive oxygen species levels, inhibiting cellular proliferation, and inducing apoptosis in HepG2 cells.  相似文献   
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