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91.
A previously unknown solid phase of H2O has been identified by its peculiar growth patterns, distinct pressure-temperature melting relations, and vibrational Raman spectra. Morphologies of ice crystals and their pressure-temperature melting relations were directly observed in a hydrothermal diamond-anvil cell for H2O bulk densities between 1203 and 1257 kilograms per cubic meter at temperatures between -10 degrees and 50 degreesC. Under these conditions, four different ice forms were observed to melt: two stable phases, ice V and ice VI, and two metastable phases, ice IV and the new ice phase. The Raman spectra and crystal morphology are consistent with a disordered anisotropic structure with some similarities to ice VI.  相似文献   
92.
93.
A superconducting point contact is used to determine the spin polarization at the Fermi energy of several metals. Because the process of supercurrent conversion at a superconductor-metal interface (Andreev reflection) is limited by the minority spin population near the Fermi surface, the differential conductance of the point contact can reveal the spin polarization of the metal. This technique has been applied to a variety of metals where the spin polarization ranges from 35 to 90 percent: Ni0.8Fe0.2, Ni, Co, Fe, NiMnSb, La0.7Sr0.3MnO3, and CrO2.  相似文献   
94.
95.
SUMMARY Sixty-two Thoroughbred horses aged between 1 and 7 years in training in Sydney had bronchoalveolar lavage (BAL) samples collected for cytological examination. All horses, except the yearlings and those with a cough, had raced at the time of the examination and the trainers reported satisfactory performance. Free erythrocytes were found In 73% of samples and haemoslderophages In 90% of the samples, Indicating Immediate or past occurrences of exercise-Induced pulmonary haemorrhage (EIPH). Bronchoalveolar fluid from the yearlings contained significantly less (P / 0.05) erythrocytes and haemosiderophages than samples from horses In other age groups. In the older horses, there was also more haemosiderln within the macrophages. No differences In BAL cytology could be attributed to gender, and there was no relationship between BAL cytology and racing performance. The main cytological findings were (mean ± sd): total nucleated cells - 832 ± 578/μL with the main cell types being: macrophages - 59 ± 10% (haemosiderophages - 20 ± 24%); neutrophlls - 9 ± 6%; lymphocytes - 31 ± 9%. The erythrocyte count was 10.3 ± 17.7% of the total cell count. Horses with chronic coughing had a higher proportion of macrophages and a lower proportion of lymphocytes in the leucocytes obtained from BAL. There was a higher occurrence of EIPH detected In BAL findings than that previously reported when endoscopic examination has been used to diagnose EIPH. The occurrence and severity of EIPH as Indicated by the BAL findings was found to be related to exercise Intensity. The cytological findings were similar to those reported in horses in the northern hemisphere. We conclude that BAL cytology may be useful In the diagnosis of various lower respiratory tract disorders and that exercise-induced pulmonary haemorrhage occurs In virtually all horses In race training.  相似文献   
96.
Objective To estimate the specificity of an absorbed enzyme-linked immuno-sorbent assay kitd for Johne's disease (JD) when used in mature cattle populations resident in northern Australia.
Design Blood samples were collected from beef cattle in northern Queensland, the Northern Territory and northern Western Australia, and from dairy cattle in northern Queensland. The specificity of a serological test for JD was estimated by testing the blood samples with an absorbed ELISA kit. Further samples were collected from cattle with positive ELISA results to determine the presence or absence of infection with Mycobacterium avium subsp paratuberculosis .
Procedure During 1995 and 1996, blood, tissue and gut contents were collected from beef cattle at abattoirs in Queensland and the Northern Territory; and blood and faecal samples were collected from dairy cattle in herds assessed to be most at risk for JD in northern Queensland. The blood samples were tested using an absorbed ELISA kit. Tissues and gut contents from beef cattle that had positive ELISA results were cultured for M avium subsp paratuberculosis , and tissues were examined histo-logically. Faecal samples from dairy cattle with positive ELISA results were cultured for M avium subsp paratuberculosis .
Results Estimates of specificity for this absorbed ELISA in mature northern Australian cattle were 98.0% (97.0 to 98.8%, 95% CI) in beef cattle, and 98.3% (96.7 to 99.3%, 95% CI) in dairy cattle.
Conclusion Estimates of specificity in this study were lower for beef cattle from the Northern Territory and northern Western Australia and for dairy cattle from northern Queensland than those quoted from studies on cattle in southern Western Australia. This should be considered when serological testing using the JD ELISA is carried out on northern Australian cattle.  相似文献   
97.
Transsphenoidal Hypophysectomy in the Dog A New Technique   总被引:1,自引:0,他引:1  
A technique for localizing the canine hypophysis regardless of the shape or size of a dog's skull was evaluated. Using known anatomic landmarks, the approximate location of the hypophysis was estimated, and three small self-threading screws were placed as radiographic markers in the exposed sphenoid bone. A cranial sinus venogram was performed and the hypophysis was outlined by the contrast-filled cavernous sinus. A circular ostectomy was centered over the hypophysis, using the previously placed screws as reference points. The technique was evaluated in eight dogs in a nonsurvival procedure. In seven dogs, hypophysectomy was complete and the ostectomy sites were centered precisely over the hypophysis.  相似文献   
98.
Abstract— —A condition of dysplasia of the right shoulder is described in a 10-month-old Labrador bitch, involving an ununited scapula tuberosity. The left shoulder showed marked "looseness" (joint laxity) similar to that of congenital subluxation of the shoulder, whilst third degree hip dysplasia was present bilaterally. Shoulder dysplasia is compared with elbow dysplasia and hip dysplasia. A link between the looseness of the left shoulder joint and the maldevelopment of the right shoulder is considered.
Résumé— —L'auteur décrit une dysplasie de l'épaule droite, constatée chez une chienne Labrador âgée de 10 mois, la tubérosité de l'omoplate ne donnant pas attache. L'épaule gauche préente une laxitt marquée, comparable à celle qu'entraîne la subluxation congénitale de l'épaule, et les hanches exhibent une dysplasie bilatérale du 3me degré. L'auteur compare la dysplasie de l'épaule, du coude et de la hanche. Il examine le rapport entre la laxité de l'articulation de l'épaule gauche et la malformation de l'épaule droite.
Zusammenfassung— —Ein Fall von Dysplasie der rechten Schulter bei einer 10 Monate alten Labradorhündin wird beschrieben. Die Tuberosität hatte sich nicht mit dem Schulterblatt vereinigt. Die linke Schulter zeigte eine beachtliche "Lockering" (loses Gelenk), ähnlich wie bei angeborener Subluxation der Schulter, und es bestand eine beidseitige Hüftdysplasie dritten Grades. Ein Vergleich zwischen Dysplasien der Schulter, des Ellbogens und der Hüfte wird aufgestellt und die Möglichkeit erwogen, daß die Lockerung des linken Schultergelenks mit der Unterentwicklung der rechten Schulter verbunden ist.  相似文献   
99.
Large mongrel dogs were anesthetized, instrumented, and subjected to electrically induced ventricular fibrillation after breathing either 100% oxygen (O2) or 10% O2 and 90% nitrogen for 10 minutes before arrest. Four minutes after arrest, open chest cardiopulmonary resuscitation (CPR) or intermittent abdominal compression closed chest CPR was initiated and continued for 20 minutes, at which time defibrillation was attempted. Central arterial and mixed venous blood samples were collected serially for the measurement of pH, carbon dioxide partial pressure (PCO2), and O2 partial pressure (PO2), and calculation of bicarbonate concentration and base excess. Mixed venous blood was collected serially for the measurement of lactate concentration. Hemodynamically variable resuscitation techniques and pre-arrest hypoxia or hyperoxia did not significantly influence blood-gas values during CPR. Mixed venous lactate concentrations after 20 minutes of CPR were significantly higher when hypoxia preceded the arrest and when intermittent abdominal compression closed chest CPR was used for resuscitation. Mixed venous PCO2 was significantly higher than arterial PCO2 in all dogs during CPR but was not significantly different before arrest.  相似文献   
100.
A commercially available absorbed ELISA for the diagnosis of Johne's disease (JD) (paratuberculosis) in cattle, the Johne's Absorbed EIA, was compared with the conventional complement-fixation test (CFT) used in Australia. Stored plasma from 3 Victorian dairy herds with a history of JD, sera from specimens submitted from animals showing clinical signs of JD and sera from the US National Repository for Paratuberculosis Specimens were used to determine the sensitivity of each test. The EIA detected 48.8% of 43 Australian animals with subclinical JD, while the CFT detected only 12 (21.4%) of 56 subclinically affected cattle. Of 150 subclinically infected US cattle, the EIA detected 47.3% and the CFT detected 52.0%. The EIA detected 59.7% of animals which at the time of sampling were shedding Mycobacterium paratuberculosis in their faeces, but showed no clinical signs of JD, while the CFT detected 57.3%. The EIA correctly identified 88.2% of 136 histologically confirmed clinical cases, and the CFT detected 83.4%. The specificity of each test was determined by testing sera collected at slaughter from animals residing in a known JD-free area of Australia, and from samples from the US National Repository of Paratuberculosis Specimens collected from certified-free herds in Wisconsin. The EIA was found to have a specificity of 99.8% when 998 Australian animals were used as the test population, and 99.0% when 196 US animals were used. The specificity of the CFT using Australian samples was 96.9% and 95.2% using American samples.  相似文献   
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