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排序方式: 共有200条查询结果,搜索用时 31 毫秒
31.
Robert L. Leonard Charles R. Goldman Gene E. Likens 《Water, air, and soil pollution》1981,15(2):153-167
Precipitation samples were collected at Davis and Lake Tahoe, California, in 1972–73 and 1977–78 and analyzed for pH and major cations and anions. Rain and snow in this region of northern California are derived primarily from winter cyclonic storms which move easterly from the Pacific Ocean over Davis and then Lake Tahoe. Precipitation at both sites was found to be more acid than water in equilibrium with atmospheric CO2. Acidity at Lake Tahoe apparently increased over the 5-yr period of the study. Sulfate was the dominant acid anion in 1972–73 (not measured in 1977–78). A major source of sulfate in precipitation was probably industry in the San Francisco Bay Area, upwind of the study sites. Automobile exhaust emissions throughout the region, which contains three major interstate highways and several large urban centers, contribute both sulfate and nitrate precursors to the atmosphere. As in the Eastern United States, these strong acid anions are influencing precipitation chemistry in northern California, including the Sierra Nevada mountains. 相似文献
32.
SUMMARY A haemodynamically significant ventricular septal defect was diagnosed in a 3-month-old male Cavalier King Charles Spaniel. A median sternotomy was performed and the 6.5 kg dog placed on cardiopulmonary bypass using pump-assisted cross-circulation. A 10 mm diameter peri-membranous ventricular septal defect was closed using a continuous suture of 4–0 polypropylene, via a 2.5 cm incision in the right ventricular outflow tract. The duration of cardiopulmonary bypass was 90 minutes. Complications in the immediate postoperative period were mild and easily managed. 相似文献
33.
WE Scherrer AE Kyles VF Samii EM Hardie PH Kass CR Gregory 《New Zealand veterinary journal》2013,61(6):330-333
AIMS: To assess the sensitivity of non-angiographic contrast-enhanced computed tomography (CT) to determine the presence of vascular invasion of cranial mediastinal masses in dogs and a cat, and to evaluate the association between vascular invasion and peri-operative mortality. METHODS: A retrospective study was conducted on 25 dogs and one cat. CT scans were completed with slices ranging from 2 to 10 mm. CT images were evaluated by a board-certifi ed radiologist blinded to previous diagnoses and surgical fi ndings. Each CT study was evaluated for vascular invasion, defi ned as disruption of the vessel wall and extension of the mass into the vessel lumen. Data retrieved from the surgery reports included surgical approach, whether vascular invasion was present, the surgeon's decision on operability, and post-operative complications. RESULTS: Computed tomographic evaluation revealed 25/26 masses had no evidence of vascular invasion. During surgical exploration, 10/26 masses were found to invade major regional vasculature; the cranial vena cava (CVC) was the vessel most commonly invaded (7/10 animals), and 4/7 (57%) patients with invasion of the CVC were euthanised or died in the perioperative period, from surgical or disease-related problems, which was signifi cantly higher than patients without vascular invasion (p=0.045). CONCLUSIONS: Non-angiographic contrast-enhanced CT was signifi cantly less sensitive for detecting vascular invasion of cranial mediastinal masses when compared with surgical evaluation. If the CVC was invaded by a tumour there was a signifi cant risk of death peri-operatively when compared with non-invasive cases. CLINICAL RELEVANCE: Due to the signifi cantly higher mortality risk associated with invasion of the CVC, a more sensitive method than CT should be investigated to determine vascular invasion of mediastinal masses pre-operatively. 相似文献
34.
BV Sanches JHF Pontes AC Basso CR Ferreira F Perecin MM Seneda 《Reproduction in domestic animals》2013,48(1):e7-e9
In this work, we evaluated whether embryo development and pregnancy rates would be affected by culturing bovine Bos indicus embryos in Synthetic Oviductal Fluid with amino acids (SOFaa) or G1/G2 sequential medium under a low‐oxygen atmosphere. Using Ovum Pick Up, we obtained 1,538 oocytes, divided into G1/G2 (n = 783) and SOFaa (n = 755). No difference was observed for blastocyst development among the groups (27.8% ± 14.6 and 34.9% ± 20.0 for G1/G2 and SOFaa respectively, p > 0.05). Transferring the embryos (n = 450) from both groups to recipients resulted in similar pregnancy rates for the G1/G2 (38.4% n = 78/203) compared to the SOFaa (39.7% n = 98/247). Our findings confirm that Bos indicus embryos cultured in SOFaa and G1/G2 under low‐oxygen atmosphere have similar in vitro (blastocyst rate) and in vivo (pregnancy rate) developmental capacity. However, embryos cultured in G1/G2 medium have higher cleavage than those cultured in SOFaa medium. 相似文献
35.
Goldman CG Loureiro JD Matteo MJ Catalano M Gonzalez AB Heredia SR Zubillaga MB Solnick JV Cremaschi GA 《Research in veterinary science》2009,86(1):18-21
Gastrointestinal lesions with uncertain etiology have been widely described among pinnipeds. The aim of our study was to investigate the presence of Helicobacter spp. in the gastric mucosa of South American fur seals (Arctocephalusaustralis). Gastric biopsies from thirteen seals, stranded on the shores of the Southwestern Atlantic Ocean in Argentina, were evaluated for the presence of Helicobacter spp. by PCR and DNA sequence analysis. Six gastric biopsies were positive for Helicobacter spp. Pairwise sequence comparisons showed less than 95% identity to novel Helicobacter spp. described from pinnipeds from North America and Australia. However, phylogenetic analysis revealed that the South American fur seal sequences clustered with 99-100% homology with H. cetorum, a species isolated from dolphins and whales. The presence of H. cetorum in pinnipeds, if confirmed by its isolation from the gastric mucosa of these mammals, demonstrates the wide host range of this bacterium in the marine environment. 相似文献
36.
37.
A 15-month-old, male neutered Staffordshire Bull Terrier cross was presented to its referring veterinarian collapsed and agonal. He was immediately intubated, manually ventilated, and treatment commenced for presumptive snake envenomation with two vials of Tiger/Multi-Brown Snake Antivenom (minimum 7000 units/vial). The dog was transferred to a referral hospital intubated. Additional diagnostics performed following arrival at the referral hospital included a urine snake venom detection kit test, which was positive for brown snake immunotype. Three additional vials of Tiger/Multi-Brown Snake Antivenom (minimum 7000 units/vial) were administered until the dog was extubated and able to stand. Venom-induced consumptive coagulopathy (VICC) was diagnosed based on prolonged clotting times and scleral haemorrhage. Paroxysms of right ventricular outflow tract (RVOT) origin ventricular arrhythmias were treated with lignocaine and sotalol. Four days after presentation, a new-grade IV/VI systolic heart murmur was auscultated, prompting an echocardiogram. An anechoic and compartmentalised mass measuring 43 mm × 19 mm was visualized within the right ventricular wall at the RVOT, immediately adjacent to the pulmonic valve. The mass was causing a RVOT obstruction. Its appearance was suggestive of an intramyocardial haematoma, most likely secondary to VICC. The dog remained cardiovascularly stable, and treatment consisted of supportive care. Recheck echocardiograms at 2 and 7 weeks after discharge revealed progressive improvement of the intramyocardial mass and resolution of the associated heart murmur. Although intramyocardial haematomas are rare, it should be considered as a differential in dogs that develop a newly diagnosed heart murmur and/or cardiac arrhythmia following brown snake envenomation. 相似文献
38.
M Boller K Kelers MA Stevenson KD Winkel S Hardjo J Heller PR Judge HM Ong AM Padula C Reddrop LCP Santos CR Sharp L Smart KL Swindells D Tabrett JR Wierenga 《Australian veterinary journal》2020,98(9):442-448
SnakeMap is a national cloud-based, veterinary snakebite registry. It was designed to prospectively collect data of the clinical circumstances and temporospatial information on cases of snake envenomation in dogs and cats. We herein introduce the project and summarise the data from the first 4 years of SnakeMap. The registry is a veterinary community-based online database allowing case entry from veterinary hospitals across Australia. Registry data comprise hospital characteristics, patient characteristics, envenoming snake type, treatment and outcome variables, including time and geolocation of the snake bite. We present summative information on select key variables from the SnakeMap registry (1 July 2015 to 30 June 2019). Twenty-eight hospitals from 6 states/territories entered 624 cases into the registry, including 419 dogs (67%) and 205 cats (33%). Bite time was available in 216 animals of which 90 (42%) were reported to be bitten in the 3 hours between 03:00 pm and 05:59 pm; median bite to presentation interval was 60 (interquartile range [IQR] 30, 211) minutes in dogs and 95 (IQR 41, 238) minutes in cats. Bites occurred in the owner's yard in 356 dogs (85%) and 53 cats (26%). A snake venom detection kit was used in 172 cases (28%) and antivenom was administered in 523 cases (85%). Most animals (n = 534, 88%) survived to discharge (median hospitalisation of 25 [IQR 16, 62] hours). SnakeMap effectively collects relevant clinical data from dogs and cats with presumed snake bite and provides locally specific information on the epidemiology of snake envenomation in small animals. 相似文献
39.
J. J. Goldman 《Plant Breeding》2008,127(6):644-646
Seventeen ISSR primers were screened on Texas bluegrass (Poa arachnifera), Kentucky bluegrass (P. pratensis), Canadian bluegrass (P. compressa), Argentine bluegrass (P. ligularis), cv. ‘Sherman’ (P. secunda), putative Texas × Kentucky (TK) (P. arachnifera ×P. pratensis) hybrids and hybrids involving Texas, Canadian, and Sherman bluegrass [(P. arachnifera × P. compressa) × (P. arachnifera ×P. secunda)], to determine whether they could be used to produce robust and reproducible DNA fingerprints and identify interspecific hybrids. Nine of the 17 primers consistently produced robust fingerprints and nine 2‐way primer combinations were also selected. DNA fingerprints were highly reproducible and the majority of the selected primers (16/18) amplified hybrid profiles using two putative TK full‐sib hybrids. Combined with a rapid DNA extraction protocol, the ISSR technique enabled a fast and practical way to detect F1 interspecific hybrids early in the breeding programme and could also be useful for other applications that require DNA‐based markers. 相似文献
40.
A cat with pelvic fractures from being hit by a car had voided no urine in 13 hours despite iv administration of fluids. Abdominal radiography had revealed the pelvic fractures and apparently intact urinary bladder. Urine did not flow from a urethral catheter, and contrast radiography revealed the catheter to be extra-urethral within the penis. Intravenous pyelography revealed intact ureters and urinary bladder; celiotomy confirmed intact urinary bladder. Cystotomy and normograde urethral catheterization allowed localization of the ruptured urethra within the deep subcutaneous tissues of the caudal portion of the abdomen. After closure of the cystotomy and celiotomy incisions, perineal urethrostomy was performed. 相似文献