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1.
Infection of striped mullet (Mugil cephalus) with Aeromonas hydrophila results in an acute septicemic disease. The disease can be experimentally induced by intramuscular injection, skin or gill scarification or by the oral route using pellets purposely seeded with bacteria. The organism was isolated from the blood 1–2 days after infection and from all organs 24 hr or longer after infection. The disease is characterized by early inflammatory and proliferative changes and later necrotic changes. Enteritis and hepatic necrosis are constant findings in aeromonad disease of M. cephalus but surface lesions are not pathognomic for these infections in mullet. Death of infected fish may be attributed to bacterial toxins which cause necrosis of parenchymal organs and soft tissue structure.  相似文献   
2.
Summary The rates of water use and leaf surface conductance of Citrullus colocynthis (Cucurbitacea) were evaluated from measurements of the surface temperature and microenvironment of leaves. At desert sites in Saudi Arabia the transpiration rates reached 0.13–0.17 g m-2 s-1 and the leaf temperatures were always close to air temperature. Leaf models (dry) placed in the canopy were considerably warmer than the air. To investigate responses over a wider range of conditions, plants were grown in a controlled environment room. It was found that when conditions were made hotter than those that occurred in the desert, the stomatal conductance increased greatly. Transpiration rate attained 0.6 g m-2 s-1 and the leaves were up to seven degrees cooler than the air. The results suggest a finely-tuned control mechanism working like a switch when the leaves experience extreme conditions, and enabling the plant to avoid lethal temperatures.  相似文献   
3.
Phytoplankton production and respiration in the Blue Nile and White Nile at Khartoum were measured during the period November 1969–January 1971 using the light and dark bottle technique. Maximum rates of production coincided with periods of maximum phytoplankton densities. In the Blue Nile gross production varied between 0.00 gCm–3d–1 during the flood season and 2.19 gCm–3d–1 (0.49 mgO2l–1h–1) during November 1969. In the White Nile the range was from 0.41 gCm–3d–1 (0.09 MgO2l–1h–1) in May to 3.74 gCm–3d–1 (0.83 MgO2l–1h–1) in November. The maximum rates of respiration in the Blue Nile and White Nile were 0.10 and 0.63 MgO2l–1h–1 respectively. The ratios net:gross production were generally higher in the White Nile than in the Blue Nile.  相似文献   
4.
Biomechanics and Modeling in Mechanobiology - A characteristic feature of arthritic diseases is cartilage extracellular matrix (ECM) degradation, often orchestrated by the overexpression of matrix...  相似文献   
5.
This study evaluates the antimicrobial effects of ethanolic extract of five herbal plants; Guava (Psidium guajava), Sage (Salvia officinalis), Rhamnus (Ziziphusspina Christi), Mulberry (Morusalba L.), and Olive (Oleaeuropaea L) leaves against several microbial population representing Gram positive, Gram negative and Mollicutes; S. aureus, E. coli, Pasteurella multocida, B. cereus, Salmonella Enteritidis and M. gallisepticum using standard agar disc diffusion technique and minimal inhibitory concentration (MIC). Different extracts reveal variable results against the microorganism under study. All extracts have no antibacterial potency for Mycoplasma gallisepticum except Psidium guajava. The results of minimal inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of the extracts against the six bacteria ranged from 625 to 5000 μg/ml. The used herbal extract could inhibit the selected microorganism under study with variable minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).  相似文献   
6.

In this study, which is the first of its kind in the gulf region, eye doses of interventional cardiologists and nurses were measured using active dosimeters for left and right eyes, in 60 percutaneous coronary interventions in three main hospitals in Kuwait. The dose given in terms of Hp(0.07) per procedure when ceiling suspended screens were used by main operators ranged from 18.5 to 30.3 µSv for the left eye and from 12.6 to 23.6 µSv for the right eye. Taking into account typical staff workload, the results show that the dose limit of 20 mSv/year to the eyes can be exceeded for interventional cardiologists in some situations, which demonstrates the need of using additional effective radiation protection tools, e.g. protective eye spectacles, in addition to the regular and proper use of ceiling suspended screens. With indications of increase in workload, the need for availability of a dedicated active dosimeter for the regular monitoring of eye doses is emphasized.

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Energy consumption and CO2 emissions have been increasing continuously over the past few decades in China and there is a pressing need to replace the fossil fuel‐based economy with an efficient low‐carbon system, tailor‐made to future requirements. China is starting an energy transition with the aim of building an energy system for the future. China has made tremendous progress in increasing the amount of renewable energy and reducing the cost of renewable energy over the last 20 years. According to the 14th 5 year plan, China aims to incorporate 20% of renewable energy to the primary energy mix and attain 27% reduction in CO2 emissions. Bioenergy crops constitute a significant proportion of biomass‐based bioenergy and have recently been promoted by the Chinese Government to help overcome food and fuel conflict. Steps are being taken to promote bioenergy crops on marginal lands in China, and various regions across the country with soil marginality have been evaluated for bioenergy crop cultivation. The present paper reviews the status of bioenergy in China and the potential status of marginal lands from different regions of China. It also elaborates on some of the policies, subsidies and incentives allocated by the Chinese Government for the promotion of biomass‐based energy. Land management and plant improvement strategies were discussed, which are effective in making marginal lands suitable for bioenergy crop cultivation. Managing planting strategies, intercropping and crop rotation are effective management practices used in China for the utilization of marginal lands. A national investigation is desirable for creating an inventory of technical and economic potential of biomass feedstocks that could be planted on marginal lands. This would assist with highlighting the pros and cons of using marginal lands for bioenergy production and effective policy making.  相似文献   
9.
This study illustrated the immunohistochemical distribution of androgen and vitamin D receptors of epididymis in 20 sexually mature ram (Rahmani breed) with average age ranged from (2_4) years and average weight ranged from (50_65kg). Androgen receptor was localized in the cytoplasm of both ciliated and non ciliated cells of efferent ductules, besides the principal cells via the entire epididymal duct. The principal cells of both corpus and proximal cauda epididymis showed the highest immunoreactivity to androgen receptors. Furthermore, vitamin D receptor was localized in the cytoplasm of all epithelium of the efferent ductules besides principal cells of all epididymal regions, however the immunoreaction was significantly higher in the efferent ductules, distal caput and distal cauda epididymis. In conclusion, these results suggest that the function of ram epididymis is regulated by both androgen and Vitamin D.  相似文献   
10.
The 6-shogaol, is a flavanone type flavonoid that is abundant in citrus fruit and has a wide range of pharmacological effects. The present study attempted to evaluate the antiurolithic effect of 6-shogaol on ethylene glycol (EG) and ammonium chloride (AC)-induced experimental urolithiasis in rats. The efficacy of 6-shogaol 50 mg/kg and 100 mg/kg was studied in EG 0.75% (V/V) and AC 1% (W/V) experimentally induced urolithiasis in rats for 21 days. The weight difference, urine volume, the levels of calcium, phosphate, magnesium, oxalate and uric acid in urine was observed. The blood urea nitrogen, creatinine, uric acid in serum and levels of malondialdehyde (MDA) and glutathione (GSH) were also measured. Histopathological analyses in kidneys were also performed. The rats weights were higher in the 6-shogaol groups than the urolithiasis group. EG caused a significant increase in serum creatinine (p < 0.05), BUN (P < 0.001), and uric acid (p < 0.01) while treatment with Cystone (750 mg/kg), and 6-shogaol (50 and 100 mg/kg) showed the significant reduction in increased serum levels of creatinine (p < 0.001), uric acid (p < 0.01) and BUN (p < 0.001). Administration of EG and AC showed statistically significant (p < 0.001) elevated levels of MDA and reduction in GSH levels. Treatment of Cystone (750 mg/kg), and 6-shogaol (50 and 100 mg/kg) significantly (p < 0.001) reduced MDA levels and an increase GSH levels as compared to EG and AC-treated group. The histological findings further attested antiurolithiatic properties of 6-shogaol. The present study attributed clinical shreds of evidence first time that claiming the significant antiurolithic effect of 6-shogaol and could be a cost-effective candidate for the prevention and treatment of urolithiasis.  相似文献   
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