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101.
The aims of the present study were to determine uterine, vaginal and placental blood flows by Doppler ultrasound cross-buffalo gestation and to evaluate the relationships among reproductive Doppler parameters and serum metabolic parameters as well as oxidative stress. Uterine (UA) and vaginal (VA) arteries were scanned every month, and placentome was scanned from month 4 till 8 in gestation. Time-averaged maximum velocity (TAMV), pulsatility index (PI), resistance index (RI), systolic/diastolic ratio (SD) and arterial diameter (AD) were used for accessing UA and VA hemodynamics. Time-averaged maximum velocity positively correlated with and AD, and both negatively correlated with their PI, RI and SD in UA and VA. TAMV and AD increased constantly in pregnancy, with maximum increase in months 4 and 9. Pulsatility index, RI and AD of UA decreased between months 4 and 9, while PI, RI and AD of VA decreased between months 5 and 9 and then increased in month 10 in pregnancy. Time-averaged maximum velocity of placentome blood flow increased exponentially from months 4 to 8, but decreased at the last two months in pregnancy. Serum lipids were significantly higher in the first month compared to all other months, while glucose was significantly lower in months 9 and 10. Malondialdehyde increased from month 3 till term, but peaked in month 5 and 10. Glutathione and catalase were highest in the first month and remained after. Time-averaged maximum velocity and AD for both UA and VA negatively correlated with serum lipids, glucose, catalase and glutathione, while positively correlated with malondialdehyde and total protein. Thus, increases in uterine blood flow (UtBF), vaginal blood flow (VaBF) and placental blood flow (PaBF) are associated with increased metabolism and oxidative stress in buffalo pregnancy.  相似文献   
102.
Fish Physiology and Biochemistry - This study aimed to find the relation of Sparus aurata (gilthead seabream) reproductive activities to some blood parameters as complete blood count, liver...  相似文献   
103.
SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) is a novel coronavirus strain that emerged at the end of 2019, causing millions of deaths so far. Despite enormous efforts being made through various drug discovery campaigns, there is still a desperate need for treatments with high efficacy and selectivity. Recently, marine sulfated polysaccharides (MSPs) have earned significant attention and are widely examined against many viral infections. This article attempted to produce a comprehensive report about MSPs from different marine sources alongside their antiviral effects against various viral species covering the last 25 years of research articles. Additionally, these reported MSPs were subjected to molecular docking and dynamic simulation experiments to ascertain potential interactions with both the receptor-binding domain (RBD) of SARS CoV-2’s spike protein (S-protein) and human angiotensin-converting enzyme-2 (ACE2). The possible binding sites on both S-protein’s RBD and ACE2 were determined based on how they bind to heparin, which has been reported to exhibit significant antiviral activity against SARS CoV-2 through binding to RBD, preventing the virus from affecting ACE2. Moreover, our modeling results illustrate that heparin can also bind to and block ACE2, acting as a competitor and protective agent against SARS CoV-2 infection. Nine of the investigated MSPs candidates exhibited promising results, taking into consideration the newly emerged SARS CoV-2 variants, of which five were not previously reported to exert antiviral activity against SARS CoV-2, including sulfated galactofucan (1), sulfated polymannuroguluronate (SPMG) (2), sulfated mannan (3), sulfated heterorhamnan (8), and chondroitin sulfate E (CS-E) (9). These results shed light on the importance of sulfated polysaccharides as potential SARS-CoV-2 inhibitors.  相似文献   
104.
105.
Four plant species, as a dry powder of their leaves, were tested against Biomphalaria alexandrina snails, the intermediate host of Schistosoma mansoni. The bioassay tests revealed the plants Datura stramonium and Sesbania sesban to be more toxic to the snails than the other two ones. Therefore, they were tested against snails’ fecundity (Mx), reproduction rate (Ro) and their infection with S. mansoni miracidia. In addition, total protein concentration and the activities of the transaminases (AsT and AlT) and phosphatases (AcP and AkP) enzymes in hemolymph and tissues of snails treated with these plants were determined. As well, glucose concentration in snails’ hemolymph was evaluated.Exposure of snails for 4 weeks to LC10 and LC25 of the plants D. stramonium and S. sesban dry powder markly suppressed their Mx and Ro. The reduction rates of Ro for snails exposed to LC25 of these plants were 62.1% and 76.4%, respectively. As well, a considerable reduction in the infection rates of snails exposed to these plants either during, pre- or post-miracidial exposure was recorded. Thus, infection rates of snails treated during miracidial exposure with LC10 of D. stramonium and S. sesban were 41.7% and 52.2%, respectively, compared to 92.6% for control group (P < 0.01). These plants, also, reduced the duration of cercarial shedding and cercarial production/snail. So, snails exposed to LC25 of these plants shed 372.8 and 223.2 cercariae/snail, respectively, compared to 766.3 cercariae/infected control snail (P < 0.01).The results, also, revealed that glucose and total protein concentrations in hemolymph of snails treated with LC10 and LC25 of these plants were decreased, meanwhile, the activities of the enzymes AsT, AlT, AcP and AkP were elevated (P < 0.01). However, the activity of AcP in tissues of treated snails was decreased compared to that of control ones. It is concluded that LC25 of the plants D. stramonium and S. sesban negatively interferes with biological and physiological activities of B. alexandrina snails, consequently it could be effective in interrupting and minimizing the transmission of S. mansoni.  相似文献   
106.
PRACTICAL RELEVANCE: Acute spinal conditions are a common emergency presentation in general veterinary practice and have the potential to cause devastating spinal cord injury (SCI) and consequent severe neurological deficits. SCI can be divided into two subgroups: exogenous SCI (vertebral fracture and/or luxation/subluxation) and endogenous SCI (intervertebral disc extrusion and ischaemic myelopathy). CLINICAL CHALLENGES: The majority of cats with SCI have concurrent injuries. The clinician must perform a thorough physical examination and prioritise and then stabilise the life-threatening problems before focusing on the neurological examination. The possibility of multiple sites of SCI and spinal shock can make interpretation of the neurological examination challenging. While plain radiographs or myelography are usually diagnostic, they do not give direct information about the integrity of the spinal cord parenchyma or the severity of any damage. If facilities or experienced staff capable of performing the necessary surgery are not available, or advanced imaging is indicated, referral to a specialist veterinary institution should be considered. AUDIENCE: This review is aimed at clinicians dealing with feline SCI in the emergency setting or at first-opinion level, and discusses causes, initial management, specific treatment and prognosis. PATIENT GROUP: While any cat may potentially be affected by SCI, there is a tendency for exogenous SCI to be more common in younger individuals and, in the authors' experience, pure-breed cats are very rarely presented. Endogenous SCI can be seen in any breed and is typically a condition of adult cats.  相似文献   
107.
The objective of this study was to determine the impact of ginger and/or thyme aqueous extracts administration on the growth rate, caecum activity, reproductive performance and semen quality of rabbits. A total of 24 V‐line male rabbits at the age of 12 weeks were divided randomly into four equal groups (6/each) until 24 weeks of age. Treatments were as follows: drinking fresh water and served as control (G1); drinking water supplemented with 100 mg/kg b. wt. of ginger aqueous extract (G2); drinking water supplemented with 50 mg/kg b. wt. of thyme aqueous extract (G3); drinking water supplemented with 100 mg/kg b. wt. of ginger aqueous extract plus 50 mg/kg b. wt. of thyme aqueous extract (G4). Administration of aqueous thyme extract with 50 mg/kg b. wt. improved (p < 0.001) feed intake and growth performance compared to control. The highest average daily gain (p < 0.001) was found for G3 rabbits followed by G4, G2 and G1 respectively. While the most efficient feed conversion ratio was found in G4. Group 3 and group 4 had significant (p < 0.05) positive effect on caecum pH, ammonia and TVFAs concentration. Data indicated that treated groups had hastened the age with heavier body weight, larger testicular size and higher testosterone level. Also, most semen characteristics (volume, progressive motility, sperm concentration and normal spermatozoa) were higher in treated groups compared with the control group. Furthermore, gathering of the spermatozoa in the lumen of the seminiferous tubules, expanded epithelial cells stature of the epididymis with stuffed lumens with sperms in treated groups. In conclusion, aqueous extracts of ginger and/or thyme can be used as a growth promoter for improving reproductive performance of V‐line male rabbits.  相似文献   
108.
109.
This study investigated the effects of arbuscular mycorrhizal (AM) colonisation by Glomus clarum on growth and fruit yield of pepper (Capsicum annum cv. 11B 14) grown at high salinity. The experiment was conducted in pots containing a mixture of perlite and sand (1:1, v/v) under glasshouse conditions. Treatments were: (1) no added NaCl without arbuscular mycorrhizae (NS-AM), (2) no added NaCl with arbuscular mycorrhizae (NS + AM), (3) added 50 mM NaCl without arbuscular mycorrhizae (S1-AM) and (4) added 100 mM NaCl without arbuscular mycorrhizae (S2-AM), (5) added 50 mM NaCl with arbuscular mycorrhizae (S1 + AM) and (4) added 100 mM NaCl with arbuscular mycorrhizae (S2 + AM). The NaCl treatments reduced pepper shoot and root dry matter, and fruit yield compared with the non-saline treatments. The concentrations of N, P and K, in the leaves were significantly reduced by salinity stress, however, mycorrhizal colonisation of the salt-stressed plants restored leaf nutrient concentrations to the levels in non-stressed plants in most cases. AM inoculation improved pepper growth under salt or saltless conditions and reduced cell membrane leakage.  相似文献   
110.
改进Faster R-CNN的田间苦瓜叶部病害检测   总被引:11,自引:9,他引:2  
为实现在自然环境条件下对苦瓜叶部病害的目标检测,该研究提出了一种基于改进的更快速区域卷积神经网络(Faster Region with Convolutional Neural Network Features,Faster R-CNN)的苦瓜叶部病害目标检测方法。Faster R-CNN以残差结构卷积神经网络Res Net-50作为该次试验的特征提取网络,将其所得特征图输入到区域建议网络提取区域建议框,并且结合苦瓜叶部病害尺寸小的特点,对原始的Faster R-CNN进行修改,增加区域建议框的尺寸个数,并在ResNet-50的基础下融入了特征金字塔网络(Feature Pyramid Networks,FPN)。结果表明,该方法训练所得的深度学习网络模型具有良好的鲁棒性,平均精度均值(Mean Average Precision,MAP)值为78.85%;融入特征金字塔网络后,所得模型的平均精度均值为86.39%,提高了7.54%,苦瓜健康叶片、白粉病、灰斑病、蔓枯病、斑点病的平均精确率(Average Precision,AP)分别为89.24%、81.48%、83.31%、88.62%和89.28%,在灰斑病检测精度上比之前可提高了16.56%,每幅图像的检测时间达0.322s,保证检测的实时性。该方法对复杂的自然环境下的苦瓜叶部病害检测具有较好的鲁棒性和较高的精度,对瓜果类疾病预防有重要的研究意义。  相似文献   
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