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1.
Light microscopic observations revealed that in camel foetuses of 25 mm crown‐to‐rump length (CRL) the primordial tubular system of the prospective lung was formed of several tubules lined by undifferentiated columnar epithelium. Intra‐epithelial neuroendocrine cells were the first elements to be differentiated in the lining epithelium of the primordial tubular system of the prospective lung as early as 25 mm CRL. On reaching 50–67 mm CRL, the primordial tubular system started to differentiate into two systems of primordial tubules, the prospective bronchial or light tubules and the future respiratory or dark tubules. The lining epithelium of the prospective bronchial tubules revealed a clear evidence of ciliogenesis as early as 80 mm CRL. From 800 mm CRL onwards, the bronchial epithelium demonstrated ciliated and non‐ciliated secretory cells. The non‐ciliated secretory cells of the bronchial epithelium of fetal camel lung showed moderate reaction to AB/PAS technique, for the first time, in fetuses reaching 600 mm CRL.  相似文献   
2.
The cryopreservation of testicular tissue is a potential method for preserving male fertility. However, the effect of cryopreservation on bovine calf testicular tissue is scarce. This study investigated the effect of different cryoprotectants on bovine calf testicular tissue at the molecular level. Testicular tissue from ten immature bovine calves (6 months) was collected after slaughter and cryopreserved in an extender containing different concentrations of the following five cryopreservation solutions (CP): bovine serum albumin (BSA) with 5% dimethyl sulfoxide (DMSO), trehalose with 5% DMSO, DMSO and glycerol and ethylene glycol (EG). After 7‐day cryopreservation, the expression levels of three spermatogonial stem cell (SSC)‐related genes, octamer‐4 (OCT4), KIT ligand (MGF/SCF) and kit oncogene (C‐KIT), were investigated by quantitative PCR (qPCR). The cell viability was highest for the tissues preserved with 30 mg/ml BSA (77.82% ± 1.22) and 40 mg/ml trehalose (74.23% ± 1.16) compared with other groups (p < 0.05), and the level of expression of the three genes was highest with 30 mg/ml BSA (p < 0.05). Compared with other CPs, the 30 mg/ml BSA and 40 mg/ml trehalose have the better cryopreserve protection. The 30 mg/ml BSA is the most viable media for the cryopreservation of testicular tissue from cattle.  相似文献   
3.
  1. Staphylococcus aureus is an important human and veterinary pathogen that causes economic loss in the poultry industry. This study aimed to compare therapeutic efficacy of 4 commonly used antibiotics in poultry on S. aureus–induced arthritis in broilers.

  2. Sixty broilers, 8 weeks of age, were assigned at random into 7 groups as follows: (1) negative control (n = 5); (2) vehicle control (n = 5); (3) sulfadiazine-trimethoprim, 250 ml/1000 l drinking water (n = 10); (4) oxytetracycline 20%, 1 mg/l drinking water (n = 10); (5) florfenicol 10%, 1/1000 v/v in drinking water (n = 10); (6) enrofloxacin 10%, 1/1000 v/v in drinking water (n = 10) and (7) positive control (n = 10).

  3. Birds in group 2 were injected with 1 ml of sterile TSB medium into the right tibiotarsal joint on d 0 while other birds (except group 1) were challenged with 1 ml of 1.2 × 1010 CFU/ml suspension of S. aureus bacteria.

  4. Antibiotic therapy was started from d 4 post challenge and continued for 5 d. At the end, birds were weighed and clinical severity of arthritis was determined. After blood collection, birds were slaughtered and tibiotarsal and hip joints were evaluated grossly. The content of inflammatory exudates of tibiotarsal joint and the degree of femoral head necrosis were recorded. Mucin clot test and histopathological evaluation were performed on right tibiotarsal joint. Serum interleukin 6 was also assayed.

  5. Sulfadiazine-trimethoprim had higher therapeutic efficiency with regard to most of the assayed criteria, whereas none of the antibiotics significantly affected femoral head necrosis and body weight. These data will help clinicians to have better antibiotic choice in field conditions.

  相似文献   
4.
This study was conducted to investigate the effects of probiotic (Primalac), prebiotic (TechnoMos) and synbiotic (Primalac + TechnoMos) supplementation on performance, immune responses, intestinal morphology and bacterial populations of ileum in broilers. A total of 240 one‐day‐old broiler chicks were randomly divided into four treatment groups which included 60 birds. Control group did not receive any treatment. The chicks in the second, third and fourth groups were fed probiotic (0.9 g/kg), prebiotic (0.9 g/kg) and probiotic (0.9 g/kg) plus probiotic (0.9 g/kg; synbiotic), respectively, at entire period. Daily feed intake, daily weight gain and feed conversion ratio were evaluated. The birds were immunized by sheep red blood cell (SRBC) on days 12 and 29 of age and serum antibody titres were measured on days 28, 35 and 42. Newcastle vaccines administered on days 9, 18 and 27 to chicks and blood samples were collected on day 42. Intestinal morphometric assessment and enumeration of intestinal bacterial populations were performed on day 42. The results indicated that consumption of probiotic, prebiotic and synbiotic had no significant effect on daily feed intake, daily body weight gain, feed conversion ratio, carcass traits, intestinal morphology and bacterial populations of ileum (p > 0.05). Consumption of prebiotic increased total and IgM anti‐SRBC titres on days 28 and 42 and antibody titre against Newcastle virus disease on day 42 (p < 0.05). Synbiotic increased only total anti‐SRBC on day 28 (p < 0.05). It is concluded that consumption of prebiotic increased humoral immunity in broilers. Therefore, supplementation of diet with prebiotic for improvement of humoral immune responses is superior to synbiotic supplementation.  相似文献   
5.
This research was conducted to study the performance and carcass parameters of broiler chickens fed diets supplemented with heat‐treated non‐starch polysaccharide degrading enzyme. A total of 432 one‐day old Ross 308 broiler chickens were allocated to five treatments: (i) CON (basal diet), (ii) E1: CON + 0.05% multi‐enzyme, (iii) E2: CON + 0.1% multi‐enzyme, (iv) E3: CON + 0.05% thermo‐resistant multi‐enzyme and (v) E4: CON + 0.1% thermo‐resistant multi‐enzyme, each treatment consisted of six replications and 12 chickens in each replication. The chickens were housed in three floor battery cages during 28‐day experimental period. On days 1–7, gain in body weight (BWG) improved by feeding the diets supplemented with thermo‐resistant multi‐enzyme. On days 7–21 and 1–28, chickens fed the diets containing thermo‐resistant multi‐enzyme showed improved (p < 0.05) BWG and feed conversion ratio (FCR) compared to CON group. Supplementing the diets with multi‐enzyme or thermo‐resistant multi‐enzyme affected the percentage of drip loss on d 1 (p < 0.05). Drip loss percentage on days 3 and 5 and also meat colour were not affected significantly. Supplementing the diets with multi‐enzyme or thermo‐resistant multi‐enzyme did not affect the relative weights of organs but compared to CON group, relative weight of breast muscle increased and abdominal fat decreased (p < 0.05). Among measured blood constituents, chickens fed supplemented diets with thermo‐resistant multi‐enzyme showed higher (p < 0.05) IgG. Counts of red and white blood cells and lymphocyte percentage were not affected. In conclusion, the results demonstrated that supplementing pelleted diets with thermo‐resistant multi‐enzyme improved performance of broiler chickens.  相似文献   
6.
正Drought is one of the most prevalent abiotic stresses that adversely affect rice productivity(Petrozza et al, 2014). Rice is very sensitive to drought stress and drought can cause 50% reduction in rice production globally(Yang et al, 2008). To meet the food needs for global population, 63% more agricultural production will be required by the year 2050 than  相似文献   
7.
Background: Phenylalanine dehydrogenase (PheDH; EC 1.4.1.20) is a NAD+-dependent enzyme that performs the reversible oxidative deamination of L-phenylalanine to phenylpyruvate. It plays an important role in detection and screening of phenylketonuria (PKU) diseases and production of chiral intermediates as well. The main goal of this study was to find a simple and rapid alternative method for purifying PheDH. Methods: The purification of recombinant Bacillus sphaericus PheDH was investigated in polyethylene glycol (PEG) and ammonium sulfate aqueous two-phase systems (ATPS). The influences of system parameters including PEG molecular weight and concentration, pH and (NH4)2SO4 concentration on enzyme partitioning were also studied. The purity of enzyme was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Results: A single extraction process was developed for separation and purification of recombinant PheDH from E. coli BL21 (DE3). The optimized conditions for partitioning and purification of PheDH were 9% (w/w) PEG-6,000 and 16% (w/w) (NH4)2SO4 at pH 8.0. The partition coefficient, recovery, yield, purification factor and specific activity values were achieved 58.7, 135%, 94.42%, 491.93 and 9828.88 U/mg, respectively. Also, the Km values for L-phenylalanine and NAD+ in oxidative deamination were 0.21 and 0.13 mM, respectively. Conclusion: The data presented in this paper demonstrated the potential of ATPS as a versatile and scaleable process for downstream processing of recombinant PheDH.  相似文献   
8.
Asadi  Z.  Mohammadi  M. H.  Shorafa  M.  Farhbakhsh  M.  Ghezelbash  E. 《Eurasian Soil Science》2020,53(6):749-759
Eurasian Soil Science - The objectives of this research are prediction of soil drainage curve using Assouline and Or (2014) adjusted soil drainage model and comparison of the predicted results with...  相似文献   
9.
Several natural products recovered from a marine-derived Aspergillus niger were tested for their inhibitory activity against SARS CoV-2 in vitro. Aurasperone A (3) was found to inhibit SARS CoV-2 efficiently (IC50 = 12.25 µM) with comparable activity with the positive control remdesivir (IC50 = 10.11 µM). Aurasperone A exerted minimal cytotoxicity on Vero E6 cells (CC50 = 32.36 mM, SI = 2641.5) and it was found to be much safer than remdesivir (CC50 = 415.22 µM, SI = 41.07). To putatively highlight its molecular target, aurasperone A was subjected to molecular docking against several key-viral protein targets followed by a series of molecular dynamics-based in silico experiments that suggested Mpro to be its primary viral protein target. More potent anti-SARS CoV-2 Mpro inhibitors can be developed according to our findings presented in the present investigation.  相似文献   
10.
The COVID-19 pandemic and its continuing emerging variants emphasize the need to discover appropriate treatment, where vaccines alone have failed to show complete protection against the new variants of the virus. Therefore, treatment of the infected cases is critical. This paper discusses the bio-guided isolation of three indole diketopiperazine alkaloids, neoechinulin A (1), echinulin (2), and eurocristatine (3), from the Red Sea-derived Aspergillus fumigatus MR2012. Neoechinulin A (1) exhibited a potent inhibitory effect against SARS-CoV-2 Mpro with IC50 value of 0.47 μM, which is comparable to the reference standard GC376. Despite the structural similarity between the three compounds, only 1 showed a promising effect. The mechanism of inhibition is discussed in light of a series of extensive molecular docking, classical and steered molecular dynamics simulation experiments. This paper sheds light on indole diketopiperazine alkaloids as a potential structural motif against SARS-CoV-2 Mpro. Additionally, it highlights the potential of different molecular docking and molecular dynamics simulation approaches in the discrimination between active and inactive structurally related Mpro inhibitors.  相似文献   
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