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91.
ObjectiveTo evaluate the anesthetic and cardiorespiratory effects of two doses of intramuscular (IM) xylazine/ketamine in alpacas, and to determine if tolazoline would reduce the anesthetic recovery time.Study designProspective randomized crossover study.AnimalsSix castrated male alpacas.MethodsEach alpaca received a low dose (LD) (0.8 mg kg−1 xylazine and 8 mg kg−1 ketamine IM) and high dose (HD) (1.2 mg kg−1 xylazine and 12 mg kg−1 ketamine IM) with a minimum of one week between trials. Time to sedation, duration of lateral recumbency and analgesia, pulse rate, respiratory rate, hemoglobin oxygen saturation, arterial blood pressure, blood-gases, and the electrocardiogram were monitored and recorded during anesthesia. With each treatment three alpacas were randomly selected to receive tolazoline (2 mg kg−1 IM) after 30 minutes of lateral recumbency.ResultsOnset of sedation, lateral recumbency and analgesia was rapid with both treatments. The HD was able to provide ≥30 minutes of anesthesia in five of six alpacas. The LD provided ≥30 minutes of anesthesia in three of six alpacas. Respiratory depression and hypoxemia occurred with the HD treatment during the first 10 minutes of lateral recumbency: two animals were severely hypoxemic and received nasal oxygen for 5 minutes. Heart rate decreased, but there were no significant changes in arterial blood pressure. Tolazoline significantly shortened the duration of recumbency with the HD.ConclusionsThe HD provided more consistent clinical effects in alpacas than the LD. Intramuscular tolazoline shortened the duration of lateral recumbency in alpacas anesthetized with the HD combination.Clinical relevanceBoth doses of the combination were effective in providing restraint in alpacas and the duration of restraint was dose dependent. Supplemental oxygen should be available if using the HD and IM administration of tolazoline will shorten the recovery time.  相似文献   
92.
93.
The Lunar Prospector neutron spectrometer data correlate well with iron and titanium abundances obtained through analysis of Clementine spectral reflectance data. With the iron and titanium dependence removed, the neutron spectrometer data also reveal regions with enhanced amounts of gadolinium and samarium, incompatible rare earth elements that are enriched in the final phases of magma crystallization. These regions are found mainly around the ramparts of the Imbrium impact basin but not around the other basins, including the much larger and deeper South Pole-Aitken basin. This result confirms the compositional uniqueness of the surface and interior of the Imbrium region.  相似文献   
94.
Recruitment of age‐0 Pacific bluefin tuna (Thunnus orientalis) from 1952 to 2014 was examined by a sequential regime shift detection method. The regime shifts in recruitment were detected in 1957, 1972, 1980, 1994 and 2009. The durations of regime shift ranged from 8–15 years and averaged 13.0 years. In both the total (1952–2014) and data rich (1980–2014) periods, negative relationships were found between recruitment and the Pacific Decadal Oscillation in autumn, and positive relationships were found between recruitment and sea surface temperature (SST) anomalies in the northern part of the East China Sea, in the southwestern part of the Sea of Japan, and in the waters off Shikoku and Tokai in summer and autumn. The 1994 and 2009 regime shifts in recruitment occurred in the same years as shifts in SST anomalies in the northern part of the East China Sea in summer. These results suggest that the ocean conditions in the northern part of the East China Sea are closely related to recruitment of Pacific bluefin tuna, and that the warmer conditions result in higher recruitment of the species.  相似文献   
95.
This study investigated the effect of acetic acid concentrations from 3 to 8% on the physicochemical and sensory quality of marinated Atlantic and Baltic herring from fresh and frozen-thawed material. The increased concentration of acetic acid was found to exert a strong impact on decreased sensory scores, weight yield, and pH value as well as on an increased brightness parameter of meat. In turn, moisture, protein hydrolysis products (PHB), total volatile bases (TVB) content, and hardness parameter were affected by the higher addition of acid to a lesser extent. Enhanced protein hydrolysis was observed only at acetic acid concentration of 5% or 5–8%, whereas there was a decrease in the content of TVB only at an acid concentration of up to 4–5%. The marinated frozen-thawed fillets, compared to the fresh ones, required a greater addition of acid in the brine, by 1.5%, to reach a similar pH value. The freezing of fish contributed also to a decrease of PHB and free hydroxyproline, along with an increased concentration of acetic acid. The marinades from frozen-thawed herring contained more TVB, had worse color, and hardness parameters, as well as less yield.  相似文献   
96.
High-mobility group box 1 (HMGB1), a nonhistone chromosomal protein, has recently been suggested as a late mediator of the inflammatory cascade. Blood HMGB1 levels are increased in a number of human diseases, and HMGB1 has been suggested to be a useful marker for disease severity and prognosis. The objective of this study was to assess the clinical usefulness of HMGB1 in dogs. Plasma HMGB1 levels, as well as C-reactive protein (CRP), a typical canine inflammatory marker, were measured in dogs with various diseases, especially systemic inflammatory response syndrome (SIRS), and dogs that had undergone surgery. HMGB1 gradually increased and attained a maximum level 72 hr after surgery, whereas CRP increased rapidly, peaking at 24 hr. Although both HMGB1 and CRP levels were significantly increased in dogs with various diseases compared with the control dogs, no correlation was found between the HMGB1 and CRP values. HMGB1 levels in the SIRS group were significantly elevated compared with those in the non-SIRS group. However, the increase in HMGB1 levels above the reference range was not indicative of SIRS. Instead, the presence of increased HMGB1 and CRP levels above the reference ranges significantly affects the poor outcome of SIRS. The present study indicates that HMGB1 is a novel canine inflammatory marker and is distinct from CRP. However, the additional clinical value of HMGB1 measurement remains unclear, and further studies are warranted.  相似文献   
97.
Objective  Although variations exist between species with respect to outcomes after cryopreservation, little is known about the differences in the susceptibility of the corneal stroma to cryoinjury. We performed this study to investigate freeze–thaw-induced damage in keratocytes and collagen in rabbit, pig, and human corneas.
Animals studied  Rabbit, pig, and human.
Procedures  We prepared 250-μm-thick anterior stroma from rabbit, pig, and human corneas after scraping off the epithelium and endothelium. Each 250-μm-thick corneal stroma without epithelium was placed in a 50-mL tube, frozen with liquid N2 for 15 min and taken out to thaw rapidly at 37 °C. This procedure of rapid freezing and thawing was repeated three times. Differences between the species with respect to cells and collagen structures were examined using hematoxylin–eosin (H&E) staining, terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assay, and transmission electron microscopy (TEM). We orthotopically transplanted the pig and rabbit corneal transplants after the triple freeze–thaw cycle into rabbit eyes and evaluated graft survival.
Results  On gross examination, rabbit corneas became opaque after the triple freeze–thaw procedure, while pig and human corneas remained transparent. Histologically, keratocytes were apoptotic on TUNEL assay and TEM in rabbit, pig, and human corneas. Collagen fibrils were fragmented and the arrangement of collagen fibrils was severely disturbed in rabbit corneas on H&E staining and TEM; collagen was well preserved in pig and human corneas. Rabbit corneal stroma underwent autolysis after transplantation, whereas the pig corneal stroma remained clear for 1 month.
Conclusions  Our study showed that rabbit corneal stroma was more susceptible to freeze–thaw injury than pig and human corneas.  相似文献   
98.
小菜蛾生物学研究——生活习性的观察   总被引:2,自引:0,他引:2  
十字花科蔬菜是杭州的主要蔬菜,占当地蔬菜总面积的56.68%。近年来,由于小菜蛾(Plutella xyloslella L.)为害猖獗,影响生产。作者认为要有效地防治小菜蛾,首先要弄清它的生活习性,但这方面国内报道甚少,因此,对小菜蛾的生活习性进行如下观察研究。  相似文献   
99.
The quantitative relationship between structure and inhibitory activity against the root growth of sawa millet of 30 N-aryl-3,4,5,6-tetrahydrophthalimides and 88 related N-aryl cyclic imide compounds (3-aryl-1,5-tetramethylenehydantoins, 4-aryl-1,2-tetramethylenetriazolidine-3,5-diones, and their thiocarbonyl analogs) was analyzed by means of physicochemical parameters of the aryl substituents and regression analysis. The results showed that, in each series of these classes of compounds, the position-specific steric effects of aromatic substituents, as represented by Verloop's STERIMOL values, are highly important in determining the inhibitory potency of the compound.  相似文献   
100.
西红柿黄顶病的初步研究   总被引:3,自引:0,他引:3  
黄頂病在广州地区发生已有30—40年,过去只是零星发生,为害不大。但自1959年开始則发生普遍,1959年发病率为5—7%,1960年为9—17%,1961年为30—50%,1962年减少至2—3%,1963年又較严重发生,大面积的番茄也几乎全部感染,而且发病早,損失很大。本病在各种品种上的病状特点是:感病后植株顶叶叶色褪綠乃至黄化,叶片变小,叶面皺縮,中部稍凸起,边緣多向下或向上卷曲;严重时,整个叶片呈“棒状”,病株矮化,不定枝丛生。但在薯叶型的品种如“Karlik”上的病状特点則是:顶部  相似文献   
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