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排序方式: 共有174条查询结果,搜索用时 15 毫秒
101.
Raessler M Wissuwa B Breul A Unger W Grimm T 《Journal of agricultural and food chemistry》2008,56(17):7649-7654
The exact and reliable determination of carbohydrates in plant samples of different origin is of great importance with respect to plant physiology. Additionally, the identification and quantification of carbohydrates are necessary for the evaluation of the impact of these compounds on the biogeochemistry of carbon. To attain this goal, it is necessary to analyze a great number of samples with both high sensitivity and selectivity within a limited time frame. This paper presents a rugged and easy method that allows the isocratic chromatographic determination of 12 carbohydrates and sugar alcohols from one sample within 30 min. The method was successfully applied to a variety of plant materials with particular emphasis on perennial ryegrass samples of the species Lolium perenne. The method was easily extended to the analysis of the polysaccharide inulin after its acidic hydrolysis into the corresponding monomers without the need for substantial change of chromatographic conditions or even the use of enzymes. It therefore offers a fundamental advantage for the analysis of the complex mixture of nonstructural carbohydrates often found in plant samples. 相似文献
102.
P Hoffmann M Klapperstück I Grimm K B?hme 《Archiv fuer experimentelle veterinaermedizin》1989,43(4):515-519
Studies were conducted into effects of acute and subacute CS2 application on intracardiac irritability and conduction in rat. Aconitine-induced arrhythmia and the coronary occlusion method were used as pathophysiological models. Under physiological conditions, short-time exposure to CS2 caused deceleration of intracardiac impulse conduction, while under pathophysiological conditions, modified arrhythmia or reduced survival rate was the result. 相似文献
103.
Gastric squamous cell carcinoma was diagnosed in three horses. Clinical signs observed in all cases were weight loss, anorexia and lethargy. Respiratory signs were prominent in one case. All three horses had depressed albumin and elevated globulin and fibrinogen concentrations. Two horses were mildly anaemic. Inflammatory exudates were present in peritoneal cavities in all cases, and cytological evaluation provided a positive diagnosis of squamous cell carcinoma in two cases. Pleural fluid samples taken from two cases were also classified as inflammatory exudates, but no neoplastic cells were detected on initial examination. In all cases the neoplasms had arisen from the oesophageal region of the stomach, and had metastised throughout the abdomen. Two cases had metastatic lesions within the pleural cavity. 相似文献
104.
Grimm SN 《Science (New York, N.Y.)》1966,151(3709):400
105.
Lamont LA Bulmer BJ Sisson DD Grimm KA Tranquilli WJ 《Journal of the American Veterinary Medical Association》2002,221(9):1276-1281
OBJECTIVE: To evaluate the effects of medetomidine on dynamic left ventricular outflow tract (LVOT) obstruction in cats with left ventricular hypertrophy. DESIGN: Clinical trial. ANIMALS: 6 domestic shorthair cats with echocardiographic evidence of dynamic LVOT obstruction. PROCEDURE: Cats were restrained in lateral recumbency, and baseline M-mode and Doppler echocardiographic examinations were performed. An ECG was recorded continuously, and blood pressure was measured indirectly with Doppler instrumentation. Medetomidine (20 microg/kg 19.1 microg/lb]) was then administered i.m., and examinations were repeated 15 minutes later. RESULTS: Significant decreases in heart rate, LVOT velocity, and the LVOT pressure gradient were documented following medetomidine administration. After adjusting for the effects of heart rate by ANCOVA, there were no significant differences in any other systolic or diastolic indices of left ventricular function. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that administration of medetomidine to cats with dynamic LVOT obstruction may result in elimination of outflow tract obstruction; medetomidine may be a suitable sedative and analgesic agent in this subpopulation of cats. 相似文献
106.
L. P. de Lorimier T. M. Fan S. Haney J. B. Grimm S. C. Charney C. A. Clifford 《Veterinary and comparative oncology》2005,3(1):39-39
Introduction: Megavoltage radiation is considered standard therapy for feline sinonasal neoplasia, but a paucity of published reports and the lack of a staging system based on advanced sectional imaging render accurate prognostication difficult. The aims of this retrospective study on feline sinonasal neoplasia were to adapt or develop a staging system based on advanced imaging, and to further define the prognosis with megavoltage radiation therapy.
Methods: Medical records were reviewed, and CT images were evaluated by a single radiologist (JBG) and staged using a modified system previously reported for dogs. Further follow‐up information was obtained by telephone interviews with the referring veterinarians or owners.
Results: Thirty‐six cats received megavoltage radiation for sinonasal neoplasia. Carcinomas (n = 17) and lymphomas (n = 16) were most common, followed by sarcomas (n = 3). A majority of immunophenotyped lymphomas were B‐cell (89%). Diagnostic CT images were available for review on 33 cats. The stage distribution was as follows: T1 (n = 3), T2 (n = 11), T3 (n = 5), T4 (n = 14). Lymphomas were more commonly T2 (n = 8) while a majority of carcinomas were T4 (n = 8). The median survival times have not yet been reached for any stage or disease subtype. The most common cause for euthanasia was local recurrence (15/19, 79%). Four cats that died of other causes lived between 1,124 and 2,322 days.
Conclusions: Feline sinonasal neoplasia is uncommon, with carcinomas and lymphomas being most frequently encountered. Megavoltage radiation therapy appears to offer improved quality and duration of life for most patients, despite advanced staged at diagnosis in a majority. 相似文献
Methods: Medical records were reviewed, and CT images were evaluated by a single radiologist (JBG) and staged using a modified system previously reported for dogs. Further follow‐up information was obtained by telephone interviews with the referring veterinarians or owners.
Results: Thirty‐six cats received megavoltage radiation for sinonasal neoplasia. Carcinomas (n = 17) and lymphomas (n = 16) were most common, followed by sarcomas (n = 3). A majority of immunophenotyped lymphomas were B‐cell (89%). Diagnostic CT images were available for review on 33 cats. The stage distribution was as follows: T1 (n = 3), T2 (n = 11), T3 (n = 5), T4 (n = 14). Lymphomas were more commonly T2 (n = 8) while a majority of carcinomas were T4 (n = 8). The median survival times have not yet been reached for any stage or disease subtype. The most common cause for euthanasia was local recurrence (15/19, 79%). Four cats that died of other causes lived between 1,124 and 2,322 days.
Conclusions: Feline sinonasal neoplasia is uncommon, with carcinomas and lymphomas being most frequently encountered. Megavoltage radiation therapy appears to offer improved quality and duration of life for most patients, despite advanced staged at diagnosis in a majority. 相似文献
107.
Roland F. Graf Stephanie Kramer-Schadt Néstor Fernández Volker Grimm 《Landscape Ecology》2007,22(6):853-866
Inter-patch connectivity can be strongly influenced by topography and matrix heterogeneity, particularly when dealing with
species with high cognitive abilities. To estimate dispersal in such systems, simulation models need to incorporate a behavioral
component of matrix effects to result in more realistic connectivity measures. Inter-patch dispersal is important for the
persistence of capercaillie (Tetrao urogallus) in central Europe, where this endangered grouse species lives in patchy populations embedded in a mountainous landscape.
We simulated capercaillie movements with an individual-based, spatially explicit dispersal model (IBM) and compared the resulting
connectivity measure with distance and an expert estimation. We used a landscape comprising discrete habitat patches, temporary
habitat, non-habitat forests, and non-habitat open land. First, we assumed that dispersing individuals have perfect knowledge
of habitat cells within the perceptual range (null model). Then, we included constraints to perception and accessibility,
i.e., mountain chains, open area and valleys (three sub-models). In a full model, all sub-models were included at once. Correlations
between the different connectivity measures were high (Spearman’s ρ > 0.7) and connectivity based on the full IBM was closer
to expert estimation than distance. For selected cases, simple distance differed strongly from the full IBM measure and the
expert estimation. Connectivity based on the IBM was strongly sensitive to the size of perceptual range with higher sensitivity
for the null model compared to the full model that included context dependent perceptual ranges. Our heuristic approach is
adequate for simulating movements of species with high cognitive abilities in strongly structured landscapes that influence
perception and permeability. 相似文献
108.
Grimm KA Tranquilli WJ Thurmon JC Benson GJ 《American journal of veterinary research》2000,61(1):42-47
OBJECTIVE: To assess duration of actions of butorphanol, medetomidine, and a butorphanol-medetomidine combination in dogs given subanesthetic doses of isoflurane (ISO). ANIMALS: 6 healthy dogs. PROCEDURE: Minimum alveolar concentration (MAC) values for ISO were determined. for each dog. Subsequently, 4 treatments were administered to each dog (saline [0.9% NaCl] solution, butorphanol [0.2 mg/kg of body weight], medetomidine [5.0 microg/kg], and a combination of butorphanol [0.2 mg/kg] and medetomidine [5.0 microg/kg]). All treatments were administered IM to dogs concurrent with isoflurane; treatment order was determined, using a randomized crossover design. Treatments were given at 7-day intervals. After mask induction with ISO and instrumentation with a rectal temperature probe, end-tidal CO2 and anesthetic gas concentrations were analyzed. End-tidal ISO concentration was reduced to 90% MAC for each dog. A tail clamp was applied 15 minutes later. After a positive response, 1 of the treatments was administered. Response to application of the tail clamp was assessed at 15-minute intervals until a positive response again was detected. RESULTS: Duration of nonresponse after administration of saline solution, butorphanol, medetomidine, and butorphanol-medetomidine (mean +/- SD) was 0.0+/-0.0, 1.5+/-1.5, 2.63+/-0.49, and 5.58+/-2.28 hours, respectively. Medetomidine effects were evident significantly longer than those for saline solution, whereas effects for butorphanol-medetomidine were evident significantly longer than for each agent administered alone. CONCLUSION AND CLINICAL RELEVANCE: During ISO-induced anesthesia, administration of medetomidine, but not butorphanol, provides longer and more consistent analgesia than does saline solution, and the combination of butorphanol-medetomidine appears superior to the use of medetomidine or butorphanol alone. 相似文献
109.
The age and/or physical condition of mulesing wounds had a significant effect on both the oviposition response of L. cuprina and the ability of the wound to support a strike. Up to 48 h after mulesing, untreated wounds elicited a strong oviposition response in contrast with chemically treated wounds, although subsequent larval development was negligible. Seven to 9-day-old wounds, however, regardless of the wound treatment, were highly attractive oviposition sites, which subsequently developed into strikes; the D3 formulation of Defiance*S, however, significantly depressed strike development and shows promise as a mules wound treatment. A marked improvement in the wound healing 14 to 16 d after mulesing coincided with a significant decrease in oviposition. Only those sheep whose wound scabs remained broken, exposing pus and raw tissue, attracted oviposition; subsequent development of the eggs into strikes was negligible. 相似文献
110.
An extruded grain designed to look like a rice kernel fortified with one of two sources of iron (elemental iron and ferrous sulfate), with and without multiple fortificant (zinc, thiamin, and folic acid), was mixed with milled Calrose rice at low (1:200), medium (1:100), and high (1:50) concentrations. The intensities of water‐like, sour taste, hay‐like musty, and alfalfa/grassy/green bean flavors were enhanced by the addition of ferrous sulfate (FeSO4) or FeSO4 plus multiple fortificants. Astringent mouthfeel was likewise affected by addition of FeSO4 or FeSO4 plus multiple fortificants. Overall, the elemental iron with multiple fortificants least affected the oxidation of the extruded kernals. Lipid oxidation products in stored fortificant increased the first two to three months and concentrations were higher in samples with FeSO4 as the iron source. 相似文献