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81.
Moraes PT Pacheco MR de Souza WM da Silva RA Neto PB Barreto CS Ribeiro AA 《Anatomia, histologia, embryologia》2002,31(6):362-366
The digestive system of the capybara has been investigated because of its coprofagia habits, important for their absorptive activity. These species present differences in terms of gastrointestinal morphological characters when compared with other rodents. Macroscopiclly, the stomach of the capybara is constituted of the following parts: cardiac, pyloric, body, fundic and gastric diverticulum. It presents two curvatures, one big and another small. Externally, the presence of gastric bands (tenias) is observed. With regards to the volumetric view, the gastric capacity varies from 850 to 2010 ml, with an average of 1498.57 ml. So, the stomach of this animal can be classified as a simple stomach, in the format of a curved sack and similar to an inverted letter 'J'. The gastric mucous membrane presents a surface filled by numerous tortuous gastric folds and longitudinally distributed along all its extension. The mucous tunic also possesses recesses located among the successive gastric folds, which were denoted as gastric parts with numerous openings described as gastric pits. In the cardiac part, a glandular epithelium with cardiac glands is noticed containing a lot of parietal and mucous neck cells. The fundic part, body and gastric diverticulum contain proper gastric glands with main, parietal and mucous neck cells. Finally, the pyloric part has pyloric glands with two cellular types, mucous neck and parietal cells. 相似文献
82.
M Chentouf B El Amiri J Sulon JF Beckers N Kirschvink B Boulanouar JL Bister 《Reproduction in domestic animals》2008,43(6):696-700
The plasma profile of pregnancy‐associated glycoprotein (PAG) and its relationship with fetal number were studied in 14 North Moroccan goats using a semi‐heterologous radioimmunoassay (RIA). Peripheral blood was collected every day during the first month of pregnancy, afterward the blood samples were collected trice a week. The PAG were first detected at day 20 of pregnancy, their levels increase to week 8 of gestation then decrease slightly until parturition. Statistical differences between goats carrying one or two foetuses are observed from week 5 of pregnancy until parturition. Factorial Discriminant Analysis provides mathematical models for the discrimination between the litter size using the PAG level and the week of pregnancy. Using only one blood sample per week, high sensitivity, specificity and overall accuracy (74%, 88% and 81%) were obtained using these models. It is concluded that the PAG RIA is an effective tool for early diagnosis of pregnancy and for discrimination between the litter sizes in North Moroccan goats. 相似文献
83.
JF Asturiano F Marco-Jiménez DS Peñaranda DL Garzón L Pérez JS Vicente M Jover 《Reproduction in domestic animals》2007,42(2):162-166
The main objective of the present work was to study the effect of cryopreservation of European eel sperm both on the sperm viability and the spermatozoa head morphology. Spermatozoa morphology was evaluated with computer-assisted morphology analysis after collection in fresh samples, after adding the freezing medium containing dimethyl sulfoxide as cryoprotectant and, finally, after the cryopreservation process and thawing. Cell viability was assessed, in both fresh and thawed samples, by Hoechst 33258 staining. Computer-assisted sperm analysis (CASA) was used to determine the percentage of motile cells and to measure motility parameters in sperm samples. A significant decrease of head perimeter (12.56%) and area (17.90%) was detected from spermatozoa in fresh to thawed samples, indicating that cells do not recover the original size after the cryopreservation process. CASA was used to measure the percentage of motile cells (51.9%) and spermatozoa motility parameters such as curvilinear, straight line and angular path velocities, as well as beating cross frequency. This technique was employed in the fresh sperm samples but proteins present at the freezing medium (L-alpha-phosphatidylcholine) made impossible to use this last technique in thawed samples. When sperm viability was assessed by Hoechst staining, a significant decrease of approximately 15% (73.10 vs 58.26%) of alive spermatozoa was registered from fresh to thawed samples. The percentage of motile cells measured by CASA in fresh samples (51.9%) was lower than the percentage of alive cells determined by Hoechst stainning, suggesting the existence of different batches of spermatozoa in different stages of development, even during the eight to tenth weeks of treatment, when the highest sperm quality was found. 相似文献
84.
85.
Selmi AL Barbudo-Selmi GR Mendes GM Figueiredo JP Lins BT 《Veterinary anaesthesia and analgesia》2004,31(3):195-206
OBJECTIVE: To evaluate the sedative, analgesic, and cardiorespiratory effects of intramascular (IM) romifidine in cats. STUDY DESIGN: Prospective, randomized experimental trial. ANIMALS: Ten healthy adult cats. METHODS: Romifidine (100, 200, and 400 microg kg(-1)) or xylazine (1 mg kg(-1)) was given IM in a cross-over study design. Heart rate (HR), respiratory rate (RR), rectal temperature (RT), hemoglobin saturation, oscillometric arterial pressure, and scores for sedation, muscle relaxation, position, auditory response, and analgesia were determined before and after drug administration. Time to recumbency, duration of recumbency, and time to recover from sedation were determined. Subjective evaluation and cardiorespiratory variables were recorded before and at regular intervals for 60 minutes after drug administration. RESULTS: Bradycardia developed in all cats that were given romifidine or xylazine. No other significant differences in physiologic parameters were observed from baseline values or between treatments. Increasing the dose of romifidine did not result in increased sedation or muscle relaxation. Cats given xylazine showed higher sedation and muscle relaxation scores over time. Analgesia scores were significantly higher after administration of romifidine (400 microg kg(-1)) and xylazine (1 mg kg(-1)) than after romifidine at 100 or 200 microg kg(-1). Duration of lateral recumbency was not significantly different between treatments; however, cats took longer to recover after administration of 400 micro g kg(-1) romifidine. CONCLUSIONS AND CLINICAL RELEVANCE: Bradycardia is the most important adverse effect after IM administration of romifidine at doses ranging from 100 to 400 microg kg(-1) or 1 mg kg(-1) of xylazine in cats. The sedative effects of romifidine at 200 microg kg(-1) are comparable to those of 1 mg kg(-1) of xylazine, although muscle relaxation and analgesia were significantly less with romifidine than with xylazine. 相似文献
86.
朝谷 1 1号由辽宁省水土保持研究所选育 ,于1 997年经辽宁省品种审定委员会审定通过。1 998年被列为省重点农技推广项目 ,计划在 1 998~ 2 0 0 0年在辽宁省朝阳市、阜新市、葫芦岛市的 8县 2区及赤峰市的宁城县推广 6.7万hm2 。1 朝谷 11号主要特征特性1 .1 农艺性状朝谷 1 1号的叶片、成株茎均为绿色 ,苗期生长快 ,株型紧凑整齐 ,株高 1 65cm左右 ,穗长 2 3~ 2 5cm ,单穗粒重 1 4~ 1 6g ,籽粒圆形、黄色 ,出谷率 83%~ 84%,谷草比 1∶1 .3。1 .2 生育期及抗性朝谷 1 1号为中早熟品种 ,生育期 1 0 4~ 1 1 4d ,4月下旬至 5月… 相似文献
87.
Flávio de Oliveira Silva Priscila das Neves Santos Evellyne de Oliveira Figueirôa Cristiane Moutinho Lagos de Melo Juliana Kelle de Andrade Lemoine Neves Francisco Vassiliepe Sousa Arruda João Batista Cajazeiras Kyria Santiago do Nascimento Edson Holanda Teixeira Benildo Sousa Cavada Ana Lúcia Figueiredo Porto Valéria Rêgo Alves Pereira 《Research in veterinary science》2014
Lectins are proteins or glycoproteins with the ability to link to carbohydrates at the cell surface in a specific and reversible manner. Studies have showed that lectins are demonstrate immunomodulatory and antitumor agents. This study aims to evaluate the effect of lectin extracted from the seeds of Canavalia brasiliensis (ConBr) on murine melanoma B16F10 cells by analyzing cell viability, apoptosis index, cell migration, production of cytokines and nitric oxide (NO). Results showed that ConBr was able to reduce cell viability and thwart apoptosis, which could be observed by decrease in cell migration. ConBr also induced NO and IL-12 synthesis. Altogether, these data demonstrate the potential of ConBr as a therapeutic agent for melanoma. 相似文献
88.
J Veverka P Thomas A Harch B Clark JF Bell B Carcich J Joseph C Chapman W Merline M Robinson M Malin LA McFadden S Murchie SE Hawkins R Farquhar N Izenberg A Cheng 《Science (New York, N.Y.)》1997,278(5346):2109-2114
On 27 June 1997, the Near Earth Asteroid Rendezvous (NEAR) spacecraft flew within 1212 kilometers of asteroid 253 Mathilde. Mathilde is an irregular, heavily cratered body measuring 66 kilometers by 48 kilometers by 46 kilometers. The asteroid's surface is dark (estimated albedo between 0.035 and 0.050) and similar in color to some CM carbonaceous chondrites. No albedo or color variations were detected. The volume derived from the images and the mass from Doppler tracking of the spacecraft yield a mean density of 1.3 +/- 0.2 grams per cubic centimeter, about half that of CM chondrites, indicating a porous interior structure. 相似文献
89.
90.