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1.
Summary The study reported in the present paper discusses the clinical and histological picture of bovine demodecosis and the morphology of Demodex mites as seen in four cows suffering from generalized demodecosis. There were no clinical signs of other skin affections. Changes in both the number and the appearance of visible skin lesions were seen and related to the level of nutrition and the exposure to sunshine of the cattle. Histological sections of some skin nodules showed the presence of mite colonies in the hair follicles. Only adults were seen in the sebaceous glands. Microscopical study of the morphology of the mites revealed the presence of two types of demodicids in the skin lesions and three types from epilated eyelashes. Morphological criteria are presented to aid in identification of species and of life stages. 相似文献
2.
Nesma I. El-naseery Asmaa A. A. Mohammed Ahmed Awad Abuel-Atta Wael A. M. Ghonimi 《Anatomia, histologia, embryologia》2021,50(5):788-800
The oesophagus is a muscular tube comprised of cervical and thoracic regions. Several studies have clarified the histological structure of the oesophagus. However, its histoarchitecture in relation to variable dietary habits of each species is still unclear. In the current study, 21 pigeons, cattle egrets and ducks, n = 7, each was used. Macroscopically, the oesophagus of cattle egrets either the cervical or thoracic parts was the longest among the pigeons and ducks. Histologically, the oesophagus comprised of four distinct tunicae: mucosa, propria submucosa, musculosa and adventitia or serosa. A great structural variation in these layers among the three investigated species was recorded. In the cervical oesophagus of pigeons, the superficial squamous cells showed perinuclear halo zone, the propria submucosa was characteristically lacked any gland. Moreover, its musculosa was very thick. On the other hand, the intraepithelial glands were characteristically distributed along the whole length of the cattle egret’s oesophagus. Interestingly, the cervical esophagus of the ducks showed submucosal associated lymphatic tissue; diffuse and nodular Ultrastructurally, the oesophageal glands showed secretory granules of variable electron densities, electron - lucent in the pigeons and ducks and electron - dense in the cattle egrets. 相似文献
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Mohammed Faez Guillaume Dom Abdulwali Nada Harhar Hicham Al-Jobory Hala J. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):230-235
Plant Foods for Human Nutrition - Argan oil is prepared by cold pressing argan kernels collected from fully ripe fruit. Argan oil market price is particularly elevated. Consequently, efficient... 相似文献
5.
Mohamed Mahmoud Sidina Mohammed El Hansali Nadia Wahid Aziz Ouatmane Abdelali Boulli Abdelmajid Haddioui 《Scientia Horticulturae》2009,123(1):110-116
The carob tree (Ceratonia siliqua L.) is an important economic resource for Morocco's rural populations. This species is used in reforestation actions and its cultivation in modern orchards is being undertaken to valorize marginal lands and substitute for drought sensitive species. However, little data is available on its intra-specific variability and its adaptability. Morphological characters of pods and seeds from 13 ecoregions of private-domesticated carob were used to assess phenotypic variation of this species. These stands extend from south-west to north-east and cover a wide range of Morocco's ecoregions. Pods length, width, thickness, seeds number, pulp weight, seeds yield and seeds length, width, thickness and weight were measured for 390 trees (30 trees per ecoregion). Statistically significant differences were found between ecoregions for all characters which were examined, what indicates a high phenotypic diversity. Principal component analysis (PCA) and hierarchical cluster of all ecoregions lead to identify two major and opposite groups (the northern ecoregions; and the central and south-western ecoregions). Ecoregions of the north of Morocco exhibited the largest and the thickest pods with the highest pulp weight while other ecoregions have relatively short pods but largest proportion of seed yield. Similarly, the northern ecoregions are characterized by the heaviest seeds. A correlation matrix between morphological characters, geographic parameters and precipitation exhibits a positive and a negative correlation of pods thickness and pulp weight with the latitude and the altitude, respectively. Seed yield and weight are negatively and positively correlated to pod width, pod thickness and pulp weight, respectively. In addition, seed weight is positively correlated with the latitude. The geographic pattern of the carob tree and its variability are discussed in this paper. 相似文献
6.
Hani A. Alhadrami Gaia Burgio Bathini Thissera Raha Orfali Suzan E. Jiffri Mohammed Yaseen Ahmed M. Sayed Mostafa E. Rateb 《Marine drugs》2022,20(3)
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
7.
8.
A Ould-Amrouche F Klein C Osdoit H O Mohammed A Touratier M Sanaa J P Mialot 《Veterinary research》1999,30(5):531-538
An epidemiological study was conducted in Orne (France) on randomly selected dairy herds (42 herds including 1,924 cows and heifers, which were at least 15 months old). The aim was primarily to estimate the seroprevalence of Neospora caninum infection from two blood samples per cow, using an enzyme-linked immunosorbent assay (ELISA) for N. caninum (one positive result indicating infection). The second aim was to test the association between some individual and herd factors and N. caninum seropositivity with a logistic model including a random term effect. The prevalence was estimated at 5.6% (107 seropositive animals). At least 27 of the 42 herds had one seropositive cow or heifer. The intra-herd seroprevalence varied from 1.1 to 8% for 18 positive herds (66.7%). Dogs were present in 36 farms and 104 of the 107 seropositive animals were exposed to them. The factors associated with individual seropositivity were the presence of cats (OR = 0.17; P < 0.001), dogs (OR = 4.35; P = 0.02), rabbits and/or ducks (OR = 2.10; P = 0.04), long calving periods (12 months) (OR = 0.44; P = 0.007), tethered housing (OR = 2.50; P = 0.01), somatic cell counts (200-400 x 10(3) cells/mL) (OR = 0.24; P < 0.001) and pond water supply (OR = 2.43; P = 0.04). In conclusion, the animal and intra-herd seroprevalences were low in dairy cows from Normandy, France. 相似文献
9.
Mohammed Piro Abdelaziz Benjouad Abdelghafor Karom Ahmed NabichNoureddine Benbihi Khalid El Allali Mohammed Machmoum Lahoussine Ouragh 《Journal of Equine Veterinary Science》2011,31(11):618-624
A total of 17 microsatellite deoxyribonucleic acid loci used routinely for horse parentage control were used to evaluate genetic diversity among normal Arabian horses and severe combined immunodeficiency (SCID) carrier Arabian horses (ArS) and normal Arab-Barb horses and SCID carrier Arab-Barb horses (ArbeS). On the basis of the genotype of 186 horses, mean allelic diversity was estimated as 6.82, 5.53, and 6.7059 in normal Arabian horses, ArS, and for both groups of Arab-Barb horses, respectively. Five specific alleles were observed in ArS and ArbeS, with one common with ArS at HMS6, whereas five alleles common between ArS and ArbeS had a high frequency. Expected and observed heterozygosity showed great heterogeneity in the population studied and were similar or higher when compared with other studies on Arabian horses. Coefficient of gene differentiation Gst of Nei associated with Nei’s genetic distance and multivariate correspondence analysis indicated a possible differentiation between the studied populations when analyzed separately according to breed. Probability of assignment of a horse to a specific group was assessed using a full and partial Bayesian approach. In all, 80.6% of Arab horses and 78.2% of Arab-Barb horses were assigned properly with a partial Bayesian test, which provided better results than the full one. These findings will be useful for identification of SCID carrier horses by using the microsatellite deoxyribonucleic acid loci used routinely for horse parentage control in our laboratory. 相似文献
10.
Youssef A. Attia Fulvia Bovera Abd El-Hamid E. Abd‐Elhamid Serena Calabr Mohamed A. Mandour Mohammed A. Al‐Harthi Sabar S. Hassan 《Journal of animal physiology and animal nutrition》2019,103(3):947-958
Sixty‐four nulliparous female rabbits were distributed among eight groups (eight animals/group). Group one was the unsupplemented control group; the other seven groups were supplemented with zinc bacitracin (ZnB) at 100 mg, or bee pollen (BP) and/or propolis (Pro) at 150 and 300 mg in a capsulated form, three times a week, day after day, continuously all over the experimental period. The experiment was run for eight parties; at each parity, 28 kids of each doe group (a total of 224 rabbits) were divided into two subgroups weaned, respectively, at 24 and 30 days of age. Thus, for each parity, there were 16 groups (eight does treatments × two weaning age, 14 rabbits per group). The growing rabbits fed the standard diets without supplements. The growth performance, the carcass traits, the liver and the spleen histology of rabbits were checked up to 90 days of age to find possible carryover effects of the supplements. The supplements had no significant effect on most of the growth performance at 90 days of age, but BP150 and BP+Pro300 increased the growth rate in comparison with ZnB group. The liver weight in the control, BP300 and Pro300 groups was higher than the ZnB one. The spleen weight was higher in the groups ZnB, BP150, Pro300 and BP+Pro300, followed by the control, BP300 and BP+Pro150 and thus Pro150. The heart % in the BP150 and Pro300 groups was higher than ZnB and BP+Pro150 groups. A lymphoid hyperplasia of splenic white pulp was observed in the BP+Pro groups, while propolis alone showed a mild activation of lymphobiosis. The Pro and BP groups showed the same picture of the control group exhibiting a hydropic degeneration of mostly hepatic cells, while the ZnB group exhibited adverse effect on the bile ducts featuring portal periductal inflammatory cells infiltration with epithelial hyperplasia reflecting chronic cholangitis. 相似文献