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51.
52.
A survey was carried out to investigate the prevalence of hard tick species (Acari: Ixodidae) on cattle and sheep southeast of Iran. A total of 972 ticks were collected from 280 infested cattle and 1,207 ticks were collected from 632 infested sheep during activating seasons of ticks in 2008–2009. The species collected from cattle were Hyalomma marginatum marginatum (50.92%), Hyalomma anatolicum excavatum (25.61%), Hyalomma anatolicum anatolicum (8.12%), Hyalomma asiaticum asiaticum (1.85%), and Rhipicephalus sanguineus (13.47%) while the species collected from sheep were R. sanguineus (36.37%), H. marginatum marginatum (30.65%), H. anatolicum excavatum (19.05%), H. asiaticum asiaticum (10.52%), Hyalomma detritum (3.14%), and Dermacentor marginatus (0.24%). The results show that, H. marginatum marginatum, H. anatolicum excavatum, and R. sanguineus are dominant tick species in the surveyed area.  相似文献   
53.
严格控制由刺盘孢属(Colletotrichum spp.)真菌引起的炭疽病对减少热带水果工业的经济损失十分重要。本文主要研究了阿拉伯胶(GA)(10%)、柠檬香草精油(LG)(0.05%)、肉桂精油(CM)(0.4%)及其复合组分在试验条件下对离体与活体香蕉和番木瓜炭疽病菌的抑制活性。结果表明,0.05%的LG和0.4%的CM对于引起香蕉和番木瓜炭疽病的两种病原菌Colletotrichum musae和Colletotrichum gloeosporioides分别具有抑制活性;单独GA处理并未表现出抑菌活性,但将0.05%LG、0.4%CM与10%GA混合处理则具有较大的抑菌活性;在各处理中,以PDA培养基中加入10%GA及0.4%CM的处理对C.musae和C.gloeosporioides这两种病原菌抑制活性最显著,对于两种病原菌菌丝生长抑制率分别为73.4%和70.0%,对孢子萌发抑制率分别为88%和85%。活体试验结果也表明,10%GA结合0.4%的CM处理具有最佳的作用效果,对C.musae和C.gloeosporioides的抑制方面表现出较强的增效作用,对人工接种的香蕉和番木瓜炭疽病导致的腐烂抑制率分别为80%和71%。品质评价的试验结果也表明,10%GA结合0.4%CM的涂膜处理具有良好效果,果实失重率、硬度、可溶性固形物和可滴定酸含量的变化均表明该处理可显著推迟果实的成熟。上述结果表明,10%阿拉伯胶结合0.4%肉桂精油处理可以作为控制诸如香蕉和番木瓜等常见热带水果采后炭疽病的生物杀菌剂。  相似文献   
54.
The search for new congeners of the leading anticancer drug doxorubicin has led to an analog that is approximately 1000 times more potent, noncardiotoxic at therapeutic dose levels, and non-cross-resistant with doxorubicin. The new anthracycline, 3'-deamino-3'-(3-cyano-4-morpholinyl)doxorubicin (MRA-CN), is produced by incorporation of the 3' amino group of doxorubicin in a new cyanomorpholinyl ring. The marked increase in potency was observed against human ovarian and breast carcinomas in vitro; it was not accompanied by an increase in cardiotoxicity in fetal mouse heart cultures. Doxorubicin and MRA-CN both produced typical cardiac ultrastructural and biochemical changes, but at equimolar concentrations. In addition, MRA-CN was not cross-resistant with doxorubicin in a variant of the human sarcoma cell line MES-SA selected for resistance to doxorubicin. Thus antitumor efficacy was dissociated from both cardiotoxicity and cross-resistance by this modification of anthracycline structure.  相似文献   
55.

Background:

Endometriosis is a complex disorder in reproductive age women which consist of stromal and epithelial cells implantation outside the uterine cavity. Adiponectin is a member of cytokine family with various metabolic roles and proliferation inhibition of many cancer cells. The aim of the present research was to determine adiponectin effect on human endometriotic stromal cells (ESCs) proliferation and their expression of adiponectin receptors.

Methods:

In this experimental study, endometrial biopsies (n=7) were taken. ESCs isolation was done by enzymatic digestion and cell filtrations. ESCs of each biopsy were divided into four groups: 0 (control), 10, 100, and 200 ng/ml adiponectin concentrations in three different times (24, 48, or 72 h). The effect of adiponectin on ESC viability and expression of mRNA Adipo receptor1 (R1) and Adipo receptor2 (R2) was determined by Trypan blue staining and semi-quantitative RT-PCR, respectively. Data were analyzed by one-way ANOVA and unpaired student’s t-test, and P<0.05 was considered statistically significant.

Results:

Adiponectin inhibited human endometriotic stromal cell proliferation in time- and dose-dependent manners significantly (P=0.001). Expression of AdipoR1 and AdipoR2 gene receptors was increased in human ESCs significantly (P<0.05).

Conclusions:

Adiponectin can suppress endometriosis by inhibiting ESC proliferation and increased AdipoR1 and AdipoR2 expression.Key Words: Adiponectin, Adiponectin receptors, Endometriosis, Stromal cells  相似文献   
56.
Persian shallot (Allium altissimum Regel.) was grown under fully irrigated conditions in a 2-year-field experiment (2010–2012) in the northeast of Iran to study and determine (i) radiation and nitrogen-use efficiency, (ii) growth analysis, (iii) carbon partitioning, and (iv) biomass production under different rates of nitrogen and cultivated bulb weights. The field experiment was performed as a randomized complete block design with a factorial arrangement of four nitrogen levels (control (100), 200, 250, and 300 kg ha?1) and two levels of cultivated bulb weight (10–20 and 20–30 g) with three replications in both years of the experiment. Our results showed that increasing the nitrogen rate and bulb weight significantly enhanced Persian shallot production. Radiation-use efficiency (1.06 to 1.27 g MJ?1), maximum crop growth rate (8.3 to 11.2 g m?2 d?1), and maximum leaf area index (1.3 to 2.6) showed a positive correlation with nitrogen rate and bulb weight. Nevertheless, nitrogen-use efficiency (0.87 to 2.38 g bulb per g nitrogen) indicated a negative relationship with applied nitrogen rate. Moreover, increasing the nitrogen application rate increased the carbon allocation to above-ground organs. On the other hand, nitrogen limited conditions increased the carbon allocation to underground organs and carbon remobilization from stem and leaves to bulbs during the late growth season. Increasing the nitrogen application rate and bulb weight may be appropriate practices for enhancing Persian shallot production; however, evaluation of the impact of nitrogen on the quality of bulbs needs to be investigated.  相似文献   
57.
Lactating dairy cows (n = 667) at random stages of the oestrous cycle were assigned to either ovsynch (O, n = 228), heatsynch (H, n = 252) or control (C, n = 187) groups. Cows in O and H groups received 100 μg of GnRH agonist, i.m. (day 0) starting at 44 ± 3 days in milk (DIM), and 500 μg of cloprostenol, i.m. (day 7). In O group, cows received 100 μg of GnRH (day 9) and were artificially inseminated without oestrus detection 16–20 h later. In H group, cows received 1 mg oestradiol benzoate (EB) i.m., 24 h after the cloprostenol injection and were artificially inseminated without oestrus detection 48–52 h after the EB injection. Cows in C group were inseminated at natural oestrus. On the day of artificial insemination (AI), cows in all groups were assigned to subgroups as follows: human Chorionic Gonadotrophin (O‐hCG) (n = 112), O‐saline (n = 116), H‐hCG (n = 123), H‐saline (n = 129), C‐hCG (n = 94) and C‐saline (n = 93) subgroups. Cows in hCG and saline subgroups received 3000 IU hCG i.m. and or 10 ml saline at day 5 post‐AI (day 15), respectively. Pregnancy status was assessed by palpation per rectum at days 40 to 45 after AI. The logistic regression model using just main effects of season (summer and winter), parity (primiparous and pluriparous), method1 (O, H and C) and method2 (hCG and saline) showed that all factors, except method1, were significant. Significant effects of season (p < 0.01), hCG and parity (p < 0.01), and a trend of parity and season (p < 0.1) were detected. A clear negative effect of warm period on first service pregnancy rate was noted (p < 0.01). The pregnancy rate was the lowest in the H protocol during warm period (p < 0.05). Treatment with hCG 5 days after AI significantly improved pregnancy rates in those cows that were treated with the H protocol compared with saline treatments (41.5% vs 24.8%; p < 0.01). O and H were more effective in primiparous than in pluriparous cows (46.1% vs 29.9%; p < 0.1 and 43.6% vs 24.6%; p < 0.01). First service pregnancy rates were higher in primiparous hCG‐treated than in pluriparous hCG‐treated cows (57.9% vs 32.3%; p < 0.01). The pregnancy rate was higher for the hCG‐treated cows compared with saline‐treated cows during warm period (37.9% vs 23.6%; p < 0.001).  相似文献   
58.
The effects of baking, boiling, microwaving, and frying on the proximate composition and fatty acid content of the edible portion of Indian white prawns (Fenneropenaeus indicus) were determined. Mean moisture, lipid, protein, and ash contents of raw prawns were 72.1, 4.32, 21.5, and 1.31%, respectively. For all cooking methods, moisture decreased and protein increased, while fatty acid compositions changed uniquely for each method. In fried prawns, the n3/n6 ratio was the lowest and significantly differed from the other treatments. The heat treatment significantly changed the proximate composition and fatty acid content. Baking and microwaving are the best methods of the four for cooking prawn while preserving their nutritional value, especially on the basis of recommended dietary intake of DHA and EPA.  相似文献   
59.
Experiments were conducted in 2009–2010 at the Agricultural and Natural Resources Research Center of Yazd, Iran, to study the effect of nitrogen levels and plant growth-promoting rhizobacteria (PGPR) containing Azotobacter sp. and Azospirillum sp. on seed yield, its components and quality traits of sesame cultivars. Treatments were arranged in a factorial experiment based on randomized complete block design with nitrogen rates (0 (control), 25 and 50 kg N ha?1), cultivars (Darab-14, GL-13 and local) and N-fixing bacteria levels (non-inoculation and inoculation) were applied with three replications. Nitrogen fertilizer significantly increased yield and yield components, but reduced oil content in 2010. Inoculating seeds with PGPR increased yield and yield components of sesame cultivars compared to the control treatment. Seed yield in PGPR inoculation with half a rate of N fertilizer treatment was more than seed yield in the full rate of N fertilizer without a PGPR inoculation treatment. N fertilizer and PGPR application significantly decreased saturated fatty acids (palmitic and stearic acid) while it significantly increased unsaturated fatty acids (oleic and linoleic acid). Oleic acid had a significant negative correlation with linoleic acid (r = ?0.79). The result showed that an application of PGPR could be usefully applied to reduce use of chemical fertilizer.  相似文献   
60.
A well developed network of roads must exist as a necessary infrastructure system in modern forestry to facilitate forest operations. But forest roads have the potential to disrupt the drainage characteristics of watersheds and lead to negative impacts on the environment with increased erosion and sediment yields. Numerous factors affect surface erosion of roads and sediment production potential; determining and ranking them could be a guide for management decisions to erosion control. In this study, the CULSED model (as an extension of ArcGIS) was used to estimate sediment delivery and the distribution of a road network, given the existing culverts. Using the model, some culverts were added to the road network around places with high sediment delivery in order to minimize it. After a correlation analysis and adjustment between sediment production and the factors, i.e., road width, road gradient, age of road and vegetation cover, the trend of changes in sediment delivery with model changes in the input was investigated with a sensitivity analysis of the model. The results show that adding new culverts to the road resulted in a significant reduction of sediment delivery. The most important factor affecting sediment delivery was road width, followed by road gradient, vegetation cover and age of road. Road width and gradient were positively correlated with sediment delivery, while vegetation cover and age of road were negatively correlated. The best model to show the relation between sediment delivery and road width as well as with road gradient was a linear model, for vegetation cover a cubic equation and for road age a power model. The results of sensitivity analysis showed that sediment delivery had the greatest sensitivity to changes of road width and was least sensitive to changes in the age of the road. This model can help to estimate sediment delivery with its spatial distribution, which can be used for optimization of cross drain systems and strategies of sediment control. Application of the model requires field trials to acquire the necessary input data. The reliability of our results is a function of the accuracy of inputs, especially digital elevation model.  相似文献   
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