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61.
62.
Nisar M Kaleem WA Khan I Adhikari A Khan N Shah MR Khan IA Qayum M Samiullah Ismail M Aman A 《Fitoterapia》2011,82(7):1008-1011
Zizyphus oxyphylla Edgew is used in Pakistan as a folk medicinal remedy for inflammatory conditions, pains especially rheumatic pain, fevers, allergy and diabetes. The aim of the current study was to scientifically validate the folk use of Z. oxyphylla Edgew by using the isolated compound in vitro and in vivo levels. Kushecarpin A was isolated from ethyl acetate fraction of the plant crude extract. Molecular docking simulations predicted Kushecarpin A as a potential new lipoxygenase (LOX) inhibitor. Kushecarpin A showed significant lipoxygenase inhibition (IC50: 7.2 ± 0.02 μM) thus validated computational prediction. It also exhibited significant and highly significant inhibition (p < 0.05 and p < 0.01) of carrageenan-induced hind paw oedema at the doses of 5, 10 and 20 mg/kg. Kushecarpin A seems to be a potentially new anti-inflammatory compound responsible for anti-inflammatory activities of Z. oxyphylla Edgew. In vitro and in vivo anti-inflammatory inflammatory activities were found in good agreement with the folk medicinal use of Z. oxyphylla Edgew in inflammatory disorders. 相似文献
63.
The stifle joint is one of the most important joints in dogs from the orthopaedic point of view. The aim of this study was
to document the morphometric values of femoral condyles, given the close relationship between the shape and function of an
anatomic structure. The left femora of 16 mid-sized dogs were used, and diameter and nine radii as well as cranial and caudal
bow lengths from each condyle were measured. The photographs were taken of the distal femora from both sides. All measurements
were obtained from these images by using software. Additionally, the rotation angle was calculated from the intercondylar
distance and the difference between lateral and medial bow lengths. In addition to the rotation angle, the difference of diameter
and nine radii between the lateral and medial condyles was determined. All radii except getting at 90° were significantly
different between the medial and lateral condyles. The greatest values were determined in the caudal part of the medial condyle.
This results the smaller contact area and a greater pressure on the underlying surface, and therefore the meniscus and articular
cartilage of the caudal part of the medial side suggests the possibility of a risk of injury as the stifle joint flexes. The
mean rotational angle of the femur was also calculated to be 2.18° laterally and 1.02° medially in the caudal and cranial
parts of condyles, respectively. The result of this study showed that the lateral and medial condyles had different shapes
in canine femur. 相似文献
64.
The chloroform and ethyl acetate extract (100 mg/kg) of Caesalpinia volkensii H. exhibited significant (P ≤ 0.05) antinociceptive activities using hot plate and writhing tests in mice while the later showed antiplasmodial activity (IC50 0.23 ± 0.07 and 4.39 ± 2.49 μg/ml) against chloroquine sensitive (D6) and chloroquine-resistant (W2), respectively. Two new furanoditerpenes [rel. 1β,5α-dihydroxyvoucapane (1) and rel. 1β,6β-dihydroxyvoucapane; 19β-methyl ester (2)] together with seven known compounds [voucapane (3), voucapan-5-ol (4), deoxycaesaldekarin C (5), caesaldekarin C (6), 5-hydroxyvinhaticoic acid (7), triacontanyl-(E)-ferulate (8), triacontanyl-(E)-caffaete (9) and 30′-hydroxytriacontanyl-(E)-ferulate (10)] were isolated from the two extracts. The administration of 3, 4, 5 and 6 (100 mg/kg i.p) caused a significant (P ≤ 0.05) reduction in the number of writhing episodes induced by acetic acid and (P ≤ 0.01) increased pain latency threshold in hot-plate test compared to control. However, the pure compounds indicated relatively (P ≤ 0.05) low antiplasmodial activity. The phytochemical constituents from the root bark of C. volkensii had better analgesic properties than antimalarial properties, justifying the use of the plant root bark as a remedy for pain. 相似文献
65.
【目的】进一步探明盐胁迫条件下营养元素K+、Ca2+和Mg2+对苗期不同水稻基因型耐盐性的影响差异,为明确作物耐盐胁迫的生理机制、提高作物耐盐胁迫能力提供参考。【方法】于2009年1—4月在严格控制水、温、光和营养元素供应的国际水稻研究所人工气候室进行水培试验,比较研究营养液中K+、Ca2+和Mg2+浓度的变化对不同水稻基因型苗期耐盐性的影响。【结果】在盐胁迫条件下(100mmol·L-1NaCl),耐盐基因型(FL478和IR651)与盐敏感基因型(IR29和Azucena)相比,植株体内有较低的Na+含量和Na+/K+、Na+/Ca2+、Na+/Mg2+比,有较高的K+含量,这些都是耐盐基因型耐盐胁迫能力高于盐敏感基因型的内在原因。盐胁迫条件下提高营养液中Ca2+和Mg2+的含量(60mg·L-1),可显著降低植株体Na+含量和Na+/K+、Na+/Ca2+、Na+/Mg2+比,明显减轻盐胁迫的危害,增强水稻耐盐胁迫能力,且Ca2+处理的效果优于Mg2+处理;而提高营养液K+含量对以上指标的影响远远小于Ca2+处理和Mg2+处理,这也是K+处理对水稻耐盐性影响相对不明显的内在原因。【结论】K+、Ca2+和Mg2+在植株体内的含量及其与Na+的比值变化都会影响水稻苗期耐盐性;适当提高水稻生长环境的Ca2+和Mg2+浓度可以明显增强植株耐盐胁迫能力,营养元素Ca2+的效果比Mg2+明显;而K+对水稻耐盐性的影响相对不明显。 相似文献
66.
The path coefficient analysis was employed to determine the contribution of boll number per plant, boll weight and seed index characters to the variation in seed-cotton yield per plant, in the American and Egyptian cotton varieties; McNair 220 and Giza 75 respectively. Data obtained from yield trials carried out at Fayoum Experimental Farm, Faculty of Agriculture, in two growing seasons, 1982 and 1983, were used in this analysis.
It was found that boll number per plant had the greatest contribution to seed cotton yield in both American and Egyptian cotton varieties. Selection for number of bolls/plant and boll weight in American Upland cotton accounts for about 75% of the yield. While in Egyptian cotton, number of bolls/plant and boll weight account for about 60% only of yield.
The arrangement of the components contributing to plant yield, according to their relative importance in McNair 220 variety was:
(1) The direct effect of bolls/plant. (2) The direct effect of boll weight. (3) The joint effect of number of bolls with boll weight. While in Giza 75 variety the arrangement was as follows:
(1) The direct effect of number of bolls per plant. (2) The joint effect of number of bolls with boll weight. (3) The direct effect of boll weight. 相似文献
It was found that boll number per plant had the greatest contribution to seed cotton yield in both American and Egyptian cotton varieties. Selection for number of bolls/plant and boll weight in American Upland cotton accounts for about 75% of the yield. While in Egyptian cotton, number of bolls/plant and boll weight account for about 60% only of yield.
The arrangement of the components contributing to plant yield, according to their relative importance in McNair 220 variety was:
(1) The direct effect of bolls/plant. (2) The direct effect of boll weight. (3) The joint effect of number of bolls with boll weight. While in Giza 75 variety the arrangement was as follows:
(1) The direct effect of number of bolls per plant. (2) The joint effect of number of bolls with boll weight. (3) The direct effect of boll weight. 相似文献
67.
Topical application of the synergists piperonyl butoxide (PB) and S,S,S-tributyl phosphorotrithioate (DEF) to second-instar larvae of a standard laboratory strain (FS) and an unselected Malaysian field strain (CH) of the diamondback moth Plutella xylostella had no significant effect on the toxicity of the acylurea insecticides, chlorfluazuron and teflubenzuron, in a subsequent leafdip bioassay. In contrast, pre-treatment with PB or DEF in acylurea-selected subpopulations of the CH strain with varying levels of cross-resistance to chlorfluazuron and teflubenzuron significantly increased (up to 34-fold and 28-fold, respectively) the toxicity of both compounds, suggesting that microsomal monooxygenases and esterases may be involved in resistance. The addition of a mineral oil, ‘Sunspray 6E’, to topically-applied chlorfluazuron consistently reduced its LD50 value, and the effect of the oil appeared to be greatest on the most resistant population of P. xylostella. However, the effects of the oil were not significant (P > 0·05) and further studies are necessary to determine whether a penetration factor is present in the CH strain. 相似文献
68.
The activities of the acylurea insect growth regulators, chlorfluazuron, teflubenzuron and difubenzuron, and the neurotoxic macrocyclic lactone, abamectin were assessed against a laboratory susceptible (FS) strain and a field (Cameron Highlands, Malaysia (CH)) strain of the diamondback moth, Plutella xylostella L. using a leaf-dip bioassay at 20°C. The time taken to achieve end-point mortality was found to vary considerably (9–17 days), being fastest with abamectin against the FS strain and slowest with difubenzuron against the CH strain. The order of activity (LC50 at F6/7) against second-instar larvae of both strains was: abamectin > chlorfluazuron = teflubenzuron ? difubenzuron. Subsequent assays (F14) with the acylureas, flufenoxuron and hexaflumuron against the FS strain suggested that the former was slightly more active than chlorfluazuron or teflubenzuron, the latter slightly less active. The CH population was found to be 12.6-, 6.7-, 6.4- and 2.3-fold less sensitive to difubenzuron, teflubenzuron, chlorfluazuron and abamectin respectively than the FS strain. Selection of sub-populations of the CH strain with chlorfluazuron (CHL-SEL) and teflubenzuron (TEF-SEL) for six generations (F6-11), resulted in LC50 resistance ratios of 109- and 315-fold respectively when compared with the FS strain, equivalent to an 18- and a 46-fold increase in resistance compared with the unselected CH strain. Marked cross-resistance was also demonstrated between chlorfluazuron and teflubenzuron in both sub-populations. However, there was no evidence of cross-resistance to dijlubenzuron and abamectin and little or no cross-resistance to flufenoxuron and hexaflumuron. Resistance to chlorfluazuron and teflubenzuron appeared to be relatively unstable in the TEF-SEL compared with the CHL-SEL sub-population (over 6–9 generations). However, reselection of the TEF-SEL population with chlorfluazuron (F18–20) led to a very rapid increase in resistance to chlorfluazuron and particularly teflubenzuron. For the latter compound, resistance factors of about 1000000 were obtained (F19, 21). Such values are probably only semi-quantitative, as above a certain level of resistance feeding bioassays with acylureas (compounds which are active to a significant extent by ingestion) are likely to become rate-limiting. 相似文献
69.
M. Nabil Alaa El-Din Ismail M. Madany A. Al-Tayaran A. Hakeem Al-Jubair A. Gomaa 《Water, air, and soil pollution》1993,66(1-2):135-143
The quality of water from 388 wells in 6 regions in the Kingdom of Saudi Arabia has been investigated with respect to pH, total dissolved salts (TDS), nitrite, ammonium, nitrate, and faecal coliforms. Concentration of TDS varied widely, from 180 to 9350 mg L?1, with a mean of 754 mg L?1. Of the 388 wells, 72 (18.6%) were above the WHO limit of 1000 mg L?1. The levels of nitrate varied significantly, ranging from 0.0 to 95.2 mg L?1, with an average value of 20.7 mg L?1. About 7.7% of the tested wells had nitrate content above the WHO limit of 45 mg L?1, and 16% of the wells showed NH4 + levels greater than 0.05 mg L?1. Faecal coliforms were present in 21.4% of the tested well waters. The results indicated that significant nutrient and faecal coliforms contaminated of well water was occurring. 相似文献
70.
The DB2 calf strain of bovine coronavirus (BCV) was used to inoculate 1-day-old specific-pathogen-free (SPF) turkey poults in three trials. In all trials, the birds developed clinical signs of enteritis at 48-72 hr postinoculation. Birds euthanatized at 3, 5, and 7 days postinoculation (DPI) had flaccid, pale intestines with watery contents, and the ceca were markedly enlarged with frothy contents. Coronavirus particles were detected by immune electron microscopy with BCV antibodies from the intestinal contents of birds killed at 3, 5, 7, and 12 DPI. Body weights of inoculated poults killed at 3, 5, and 7 DPI were significantly reduced as compared with controls. Hemagglutinating antibodies were detected in sera of convalescent birds at 12 DPI. However, experimental inoculation of 1-day-old SPF chicks in two trials with the same virus resulted in no clinical signs or macroscopic or microscopic lesions. No coronaviruses were detected from intestinal contents, and there were no significant differences in body weights of inoculated and noninoculated control chicks. 相似文献