A Chemoautotrophically Based Cave Ecosystem   总被引：1，自引：0，他引：1  

SM Sarbu  TC Kane  BK Kinkle 《Science (New York, N.Y.)》1996,272(5270):1953-1955

Microbial mats discovered in a ground-water ecosystem in southern Romania contain chemoautotrophic bacteria that fix inorganic carbon, using hydrogen sulfide as an energy source. Analysis of stable carbon and nitrogen isotopes showed that this chemoautotrophic production is the food base for 48 species of cave-adapted terrestrial and aquatic invertebrates, 33 of which are endemic to this ecosystem. This is the only cave ecosystem known to be supported by in situ autotrophic production, and it contains the only terrestrial community known to be chemoautotrophically based.  相似文献   

Growth of SiO2 at room temperature with the use of catalyzed sequential half-reactions     

JW Klaus  O Sneh  SM George 《Science (New York, N.Y.)》1997,278(5345):1934-1936

Films of silicon dioxide (SiO2) were deposited at room temperature by means of catalyzed binary reaction sequence chemistry. The binary reaction SiCl4 + 2H2O --> SiO2 + 4HCl was separated into SiCl4 and H2O half-reactions, and the half-reactions were then performed in an ABAB ellipsis sequence and catalyzed with pyridine. The pyridine catalyst lowered the deposition temperature from >600 to 300 kelvin and reduced the reactant flux required for complete reactions from approximately 10(9) to approximately 10(4) Langmuirs. Growth rates of approximately 2.1 angstroms per AB reaction cycle were obtained at room temperature for reactant pressures of 15 millitorr and 60-second exposure times with 200 millitorr of pyridine. This catalytic technique may be general and should facilitate the chemical vapor deposition of other oxide and nitride materials.  相似文献   

BIOMECHANICAL COMPARISON OF THREE INTERNAL FIXATIONS FOR TREATMENT OF SLIPPED CAPITAL FEMORAL EPIPHYSIS IN IMMATURE DOGS     

Belkoff SM  Millis DL  Probst CW 《Veterinary surgery : VS》1993,22(3):183-183

  相似文献   

Investigation of Caval Syndrome in Dogs Experimentally Infected With Dirofilaria immitis     

Clarke E. Atkins DVM    Bruce W. Keene DVM  MS  Sheila M. McGuirk DVM  PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1988,2(1):36-40

Nine of 16 dogs inoculated with 200 infective heartworm larvae developed caval syndrome (CS) of heartworm disease (HWD). There was no difference between dogs that did and did not develop CS with regard to total heartworm burden, burden relative to body weight, or female heartworm burden, indicating that factors other than worm mass are involved in the pathogenesis of CS. Male dogs were twice as frequently affected as females, although this finding was not statistically significant. Dogs afflicted with CS exhibited radiographic, pathologic, and hemodynamic evidence of chronic HWD. In a model of single heartworm exposure, these findings strongly support the theory that CS develops due to retrograde migration of adult worms from the pulmonary arteries and right ventricle to the right atrium and venae cavae. Pulmonary artery pressures were dramatically and significantly greater in dogs with CS (60 +/- 18 torr) as compared to non-CS (30 +/- 4 torr) dogs with equal worm burdens.  相似文献   

青贮机械化系统的修理费用和可靠性     

Ward  SM 《畜牧机械》1989,(5):23-26

  相似文献   

Plasma endotoxin concentration in horses: a methods study     

Peek SF  Borah S  Semrad S  McGuirk S  Slack JA  Patton E  Coombs D  Lien L  Darien BJ 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2004,33(1):29-31

Background: Accurate determination of plasma endotoxin concentration is critical for ex vivo and in vitro cellular and molecular studies of endotoxemia in horses. However, reports are conflicting with respect to anticoagulant, handling, and sample preparation.

Objective:

Objective: The purpose of this study was to determine the effect of blood sample fraction and handling time on measurement of endotoxin concentration in horses.

Methods:

Methods: Whole blood, anticoagulated with 3.8% (0.12 M) sodium citrate (9:1), was collected from 5 healthy horses. Whole blood (WB), platelet-rich plasma (PRP), and platelet-poor plasma (PPP) were spiked with endotoxin (2 EU/mL). Endotoxin-spiked WB samples were centrifuged immediately to generate PRP for measurement. Endotoxin concentration was subsequently measured by Limulus amebocyte assay at 0, 15, 30, 45, and 60 minutes. Assays were performed in triplicate and results were analyzed using Student's t -test, with significance set at P < .05.

Results:

Results: Mean endotoxin concentrations in 2 EU/mL-spiked WB were significantly different from those in PPP at all time points tested. Recovery of endotoxin in PRP generated from WB was significantly diminished after just 15 minutes.

Conclusion:

Conclusion: PRP generated from WB is significantly more reliable than PPP in determining endotoxin concentration ex vivo. Measurement of endotoxin in PRP generated from WB was significantly diminished after 15 min, identifying a time frame within which to process blood samples for endotoxin analysis.  相似文献   

What is your diagnosis? Chronic bronchointerstitial pneumonia     

Poulsen KP  Marques FJ  Ballegeer EA  McGuirk SM  Dubielzig RR  Peek S 《Journal of the American Veterinary Medical Association》2006,228(1):35-36

  相似文献   

Effects of the haemoglobin-based oxygen carrier Hemoglobin glutamer-200 (bovine) on intestinal perfusion and oxygenation in a canine hypovolaemia model     

B  Driessen  JS Jahr†  F Lurie†  SM Griffey†  RA Gunther† 《Veterinary anaesthesia and analgesia》2001,28(4):204-205

  相似文献   

Squamous cell carcinoma in a tuatara (Sphenodon punctatus)     

WD Roe  MR Alley  SM Cooper  L Hazley 《New Zealand veterinary journal》2013,61(5):207-210

CASE HISTORY: A mature male tuatara was presented with a history of recurrent cloacal prolapse.

CLINICAL AND PATHOLOGICAL FINDINGS: The prolapsed tissue included a 12 mm diameter mass, which histologically showed cords and nodules of neoplastic epithelial cells.

DIAGNOSIS: The mass was diagnosed as a squamous cell carcinoma with ulceration of the overlying stratified squamous epithelium and diffuse inflammation of the surrounding dermis.

CLINICAL RELEVANCE: This case presented a rare opportunity to investigate squamous cell carcinoma in a long-lived lower vertebrate species. Future recurrence or metastasis of the mass may add useful information to the current base of knowledge of the behaviour of malignant neoplasms in reptiles.  相似文献   

Antimicrobial stewardship in the dairy industry: responding to the threat of antimicrobial resistance     

JE Coombe  SM Tymms  M Humphris 《Australian veterinary journal》2019,97(7):231-232

Dairy Australia is the national service body for the Australian dairy industry. Its role is to help farmers adapt to a changing operating environment and achieve a profitable, sustainable dairy industry. Although the use of antibiotics in Australian agriculture is relatively low in global terms, Dairy Australia recognises important drivers for continuous improvement in antimicrobial stewardship (AMS). Dairy Australia’s first strategic priority is to support profitable farms. This priority has driven the development of a range of on‐farm change management programs in the animal health and welfare fields to optimise the unit cost of production and dairy cattle welfare. Dairy Australia’s third strategic priority is to further develop a ‘trusted dairy industry’. Previous and current work under these two strategies position the dairy industry favourably with respect to confronting the challenge of antimicrobial resistance (AMR) and supporting sound AMS with the guiding principle of ‘as little as possible, as much as necessary’. However, given an incomplete but ongoing threat of AMR, more work is needed. Supported by Dairy Australia, the dairy industry has developed an antimicrobial use strategy aligning with the Australian Animal Sector National AMR Plan 2018.  相似文献