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131.
132.
It was the aim of this study to investigate the regional variations in surface temperature and sweating rate and to visualize body thermal windows responsible for the dissipation of excess body heat in dromedary camels. This study was conducted on five dromedary camels with mean body weight of 450 ± 20.5 kg and 2 years of age. Sweating rate, skin and body surface temperature showed significant (P < 0.001) circadian variation together with the variation in ambient temperature. However, daily mean values of sweating rate, skin and body surface temperature measured on seven regions of the camel body did not significantly differ. The variation in body surface temperature compared to the variation in skin temperature was higher in the hump compared to the axillary and flank regions, indicating the significance of camel's fur in protecting the skin from daily variation in ambient temperature. Infrared thermography revealed that flank and axillary regions had lower thermal gradients at higher ambient temperature (Ta) and higher thermal gradients at lower Ta, which might indicate the working of flank and axillary regions as thermal windows dissipating heat during the night. Sweating rate showed moderate correlation to skin and body surface temperatures, which might indicate their working as potential thermal drivers of sweating in camels.  相似文献   
133.
Yin H  Luo J  Guan G  Lu B  Ma M  Zhang Q  Lu W  Lu C  Ahmed J 《Veterinary parasitology》2002,108(1):21-30
Experiments on the transmission of an unidentified Theileria sp. infective for small ruminants by Haemaphysalis qinghaiensis and Hyalomma anatolicum anatolicum were carried out. Three Theileria-free batches of adult, larvae, and nymphs of laboratory reared H. qinghaiensis and Hy. a. anatolicum ticks were infected by feeding them on sheep infected with Theileria sp. The Theileria sp. was originally isolated from adult ticks of H. qinghaiensis, by inoculation of blood stabilates or tick transmission. H. qinghaiensis has been shown to be capable of transmitting the Theileria sp. infective for small ruminants transstadially to sheep and goats. The nymphs developed from the larvae engorged on the sheep infected with the parasite transmitted the pathogen to splenectomized sheep with prepatent periods of 30, 31 days, respectively; but the subsequent adult ticks of H. qinghaiensis derived from the nymphs did not transmit the pathogen to sheep. However, adults developed from the nymphs engorged on the sheep infected with the parasite transmitted the pathogen to sheep with prepatent periods of 24-27 days. The larvae, nymphs and adult ticks derived from female H. qinghaiensis ticks engorged on infected sheep were not able to transmit the parasite transovarially. The same experiments were done with Hy. a. anatolicum, but examination for presence of piroplasma of Theileria sp. from all animals were negative, demonstrating that Hy. a. anatolicum could not transmit the organism to sheep or goats.  相似文献   
134.
Studying the impregnation and distribution of oil-based preservative in dried wood is complicated as wood is a nonhomogeneous, hygroscopic and porous material, and especially of anisotropic nature. However, this study is important since it has influence on the durability of wood. To enhance the durability of thermally modified wood, a new method for preservative impregnation is introduced, avoiding the need for external pressure or vacuum. This article presents a study on preservative distribution in thermally treated Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) sapwood using computed tomography scanning, light microscopy, and scanning electron microscopy. Secondary treatment of thermally modified wood was performed on a laboratory scale by impregnation with two types of preservatives, viz. Elit Träskydd (Beckers) and pine tar (tar), to evaluate their distribution in the wood cells. Preservative solutions were impregnated in the wood using a simple and effective method. Samples were preheated to 170 °C in a drying oven and immediately submerged in preservative solutions for simultaneous impregnation and cooling. Tar penetration was found higher than Beckers, and their distribution decreased with increasing sample length. Owing to some anatomical properties, uptake of preservatives was low in spruce. Besides, dry-induced interstitial spaces, which are proven important flow paths for seasoned wood, were not observed in this species.  相似文献   
135.
Establishment of Protected Areas (PAs), in the face of rapid deforestation, forest degradation and climate change has been one of the key efforts in conservation of biodiversity worldwide in recent times. While Bangladesh has gained a degree of prominence in the world for its successful social forestry programs, the concept of collaborative protected area management is rather new in the country, initiated in 2004 by the Bangladesh Forest Department in five PAs with financial assistance from USAID. Based on empirical evidence from three of the pilot PAs, we examined the achievements and associated challenges and prospects for co-management. Our fieldwork revealed a number of challenges faced by co-management institutions: (1) institutions were dominated by the elite group, overshadowing the voice of the community people; (2) mutual trust and collective performance are key to good governance but had not taken root in the PAs; (3) encroachment onto forest land and subsequent conversion to agriculture remained a serious problem that discouraged forest-dependent people from participating actively in co-management initiatives; (4) legal provisions (including acts, rules and policies) were not clearly and adequately disseminated and understood at the community level; (5) there remained a degree of ambiguity regarding the roles and responsibilities of forest department (FD) and co-management committees (CMC) in field operations, and this was not enhancing transparency and accountability of the overall initiative; (6) the long-term sustainability of co-management institutions was another major concern, as the local intuitional structure was still in a nascent stage, and provisioning of resources (either internally or externally) remained somewhat uncertain. We offer recommendations for improvement.  相似文献   
136.
Bovine tuberculosis (BTB) is a widespread zoonosis in developing countries but has received little attention in many sub-Saharan African countries including Sudan and particularly in some parts such as Darfur states. This study aimed to detect bovine tuberculosis among caseous materials of cattle slaughtered in abattoirs in South Darfur State, Sudan by using microscopic and PCR-based methods. The study was a cross-sectional abattoir-based study which examined a total of 6,680 bovine carcasses for caseous lesions in South Darfur State between 2007 and 2009. Collected specimens were examined for the presence of acid-fast bacilli (AFB) by using microscopic and culture techniques. Isolated mycobacteria were identified by selected conventional cultural and biochemical tests in comparison to a single tube multiplex PCR (m-PCR) assay which detect Mycobacterium bovis-specific 168-bp amplicons. Of the total 6,680 slaughtered cattle examined in South Darfur, 400 (6 %) showed caseations restricted to lymph nodes (86.8 %) or generalized (13.2 %). Bovine tuberculosis was diagnosed in 12 (0.18 %), bovine farcy in 59 (0.88 %), unidentified mycobacteria in 6 (0.09 %), and missed or contaminated cultures in 7 (0.1 %). Out of 18 cultures with nonbranching acid-fast rods, 12 amplified unique 168-bp sequence specific for M. bovis and subsequently confirmed as M. bovis. With the exception of the reference M. tuberculosis strains, none of the remaining AFB amplified the 337-bp amplicon specific for M. tuberculosis. It could be concluded that bovine tuberculosis is prevalent among cattle in South Darfur representing 4.5 % from all slaughtered cattle with caseous lesions. The study sustains microscopy as a useful and accessible technique for detecting AFB. m-PCR assay proved to be valuable for confirmation of BTB and its differentiation from other related mycobacteriosis, notably bovine farcy.  相似文献   
137.
The aim of this study was to determine whether glucocorticoid production could be monitored non-invasively in dromedary camels by measuring faecal cortisol metabolites (FCMs). Five Sudanese dromedaries, two males and three females, were injected with a synthetic adrenocorticotropic hormone (ACTH) analogue. Blood samples were collected pre- and post-ACTH injection. Faeces were sampled after spontaneous defecation for five consecutive days (2 days before and 3 days after ACTH injection). Baseline plasma cortisol values ranged from 0.6 to 10.8 ng/ml in males and from 1.1 to 16.6 ng/ml in females, while peak values after ACTH injection were 10.9–41.9 in males and 10–42.2 ng/ml in females. Peak blood cortisol values were reached between 1.5 and 2.0 h after ACTH injection. The concentration of FCMs increased after ACTH injection in the faeces of both sexes, although steroid levels peaked earlier in males [24 h; (286.7–2,559.7 ng/g faeces)] than in females [36–48 h; (1,182.6–5,169.1 ng/g faeces)], reflecting increases of 3.1–8.3- and 4.3–8-fold above baseline levels. To detect chromatographic patterns of immunoreactive FCMs, faecal samples with high FCM concentrations from both sexes were pooled and subjected to reverse phase high performance liquid chromatography (RP-HPLC). RP-HPLC analysis revealed sex differences in the polarity of FCMs, with females showing more polar FCMs than males. We concluded that stimulation of adrenocortical activity by ACTH injection resulted in a measurable increase in blood cortisol that was reliably paralleled by increases in FCM levels. Thus, measurement of FCMs is a powerful tool for monitoring the adrenocortical responses of dromedaries to stressors in field conditions.  相似文献   
138.
Fusidic acid known to has antibacterial, antifungal, and antimalarial activities. Fusidic acid blocks translation elongation factor G gene in Plasmodium falciparum. In the present study, the inhibitory effects of fusidic acid on the in vitro growth of bovine and equine Babesia parasites were evaluated. The inhibitory effect of fusidic acid on the in vivo growth of Babesia microti was also assessed. The in vitro growth of four Babesia species that were tested was significantly inhibited (P < 0.05) by micromolar concentrations of fusidic acid (IC50 values = 144.8, 17.3, 33.3, and 56.25 μM for Babesia bovis, Babesia bigemina, Babesia caballi, and Theileria equi, respectively). Combinations of fusidic acid with diminazene aceturate synergistically potentiated its inhibitory effects in vitro on B. bovis and B. caballi. In B. microti-infected mice, fusidic acid caused significant (P < 0.05) inhibition of the growth of B. microti at the dose of 500 mg/kg BW relative to control group. These results indicate that fusidic acid might be incorporated in treatment of babesiosis.  相似文献   
139.
In this study, retinal whole‐mount specimens were prepared and stained with 0.1% cresyl violet for the ganglion cell study in the native duck (Anas platyrhynchos). The total number, distribution and size of these cells were determined in different retinal regions. The mean total number of ganglion cells was 1 598 501. The retinal area centralis had the highest ganglion cell density with 11 200 cells/mm2. Number of ganglion cell bodies was the highest in temporal area, followed by dorsal, nasal and ventral areas. Ganglion cell size ranged from 5.25 to 80 μm2. In the temporal and nasal region, most of the cells were ranged from 15 to 25 μm2, and in the dorsal and ventral region, most of the cells were ranged from 12 to 25 μm2. There was a marked trend for the retinal ganglion cell size to increase as the population density decrease towards the periphery. A population of small ganglion cells persisted into the central area just above the optic disc and the largest soma area was in the ventral zone of the retina. Thus, the specialisation of ganglion cell densities and their sizes support the notion that the conduction of visual information towards the brain from all regions of the retina is not uniform, and the central area is the fine quality area for vision in native duck.  相似文献   
140.
Bioassay-guided fractionation using different chromatographic and spectroscopic techniques in the analysis of the Red Sea soft coral Litophyton arboreum led to the isolation of nine compounds; sarcophytol M (1), alismol (2), 24-methylcholesta-5,24(28)-diene-3β-ol (3), 10-O-methyl alismoxide (4), alismoxide (5), (S)-chimyl alcohol (6), 7β-acetoxy-24-methylcholesta-5-24(28)-diene-3,19-diol (7), erythro-N-dodecanoyl-docosasphinga-(4E,8E)-dienine (8), and 24-methylcholesta-5,24(28)-diene-3β,7β,19-triol (9). Some of the isolated compounds demonstrated potent cytotoxic- and/or cytostatic activity against HeLa and U937 cancer cell lines and inhibitory activity against HIV-1 protease (PR). Compound 7 was strongly cytotoxic against HeLa cells (CC50 4.3 ± 0.75 µM), with selectivity index of SI 8.1, which was confirmed by real time cell electronic sensing (RT-CES). Compounds 2, 7, and 8 showed strong inhibitory activity against HIV-1 PR at IC50s of 7.20 ± 0.7, 4.85 ± 0.18, and 4.80 ± 0.92 µM respectively. In silico docking of most compounds presented comparable scores to that of acetyl pepstatin, a known HIV-1 PR inhibitor. Interestingly, compound 8 showed potent HIV-1 PR inhibitory activity in the absence of cytotoxicity against the cell lines used. In addition, compounds 2 and 5 demonstrated cytostatic action in HeLa cells, revealing potential use in virostatic cocktails. Taken together, data presented here suggest Litophyton arboreum to contain promising compounds for further investigation against the diseases mentioned.  相似文献   
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