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排序方式: 共有192条查询结果,搜索用时 9 毫秒
41.
The salinization of Mirror Lake in the White Mountains of New Hampshire has been ongoing steadily since Interstate 93 (I-93) was built through the NE subcatchment of the lake in the fall and winter of 1969–1970. Salt added to I-93 during winter as a deicer has been transported to the lake by different quantified, hydrologic pathways, but primarily from the Northeast Tributary, which was intersected by I-93. Now, surprisingly, after the New Hampshire Department of Transportation has spent more than $500,000 on recent structural modifications to divert salt from I-93 away from the Northeast subcatchment of Mirror Lake, applications of salt to a small, town road traversing the other two subcatchments for the lake and servicing a new housing development, have become the major source of salt to the lake. Streamflow from these two subcatchments currently provides more than three times as much salt to the lake as from I-93, and the salt concentration in the lake continues to rise. 相似文献
42.
肉鸡达到目标出栏体重需要一段时间,为了进一步缩短这一时间,就要考虑从遗传进展、营养和管理入手。况且,面对市场对鸡肉产品的细化需求,肉鸡屠宰体重就必须越来越精确和一致。虽然这两个因素不失为是促进改善终端产品的简捷途径, 相似文献
43.
Pamela A. Wilkins DVM PhD DACVIM DACVECC Cynthia M. Otto DVM PhD DACVECC James E. Baumgardner MD PhD Bettina Dunkel DVM DACVIM DACVECC Daniela Bedenice DVM DACVIM DACVECC Mary Rose Paradis DVM DACVIM Francesco Staffieri DVM PhD Rebecca S. Syring DVM DACVECC Joanne Slack DVM DACVIM Salvatore Grasso MD Gene Pranzo Esq. 《Journal of Veterinary Emergency and Critical Care》2007,17(4):333-339
Background: As veterinary medicine has become more sophisticated, with greater numbers of veterinary patients receiving intensive care, more patients with an acute respiratory distress (ARDS)‐like syndrome have been recognized. Methods: A consensus definition meeting was held for the purpose of developing veterinary‐specific definitions for acute lung injury (ALI) and ARDS. Results/conclusions: Three clinically based definitions for acute lung injury and acute respiratory distress‐like syndromes occurring in veterinary patients were described. Neonatal equine respiratory distress syndrome (NERDS) was defined separately due to the specific requirement for primary developmental surfactant dysfunction and lack of an inflammatory component. Five diagnostic criteria categories were established for Veterinary ALI/ARDS (Vet ALI/ARDS) with 4 required and a fifth highly recommended criteria. A strong consensus was reached that onset of respiratory distress must have been acute and that known risk factors must be present. Additional criteria included evidence of pulmonary capillary leak with no evidence of increased pulmonary capillary pressure, evidence of inefficient gas exchange and, finally, evidence of inflammation. Some features of ALI/ARDS in the neonatal horse were recognized as unique, therefore, equine neonatal ALI/ARDS (EqNALI/EqNARDS) was similarly defined but with a graded gas exchange inefficiency table to allow for normal developmental changes in gas exchange. Use of these definitions in planning prospective studies of these problems in veterinary patients should allow for more direct comparisons of studies and clinical trials, with a larger goal of improving outcome in veterinary patients. 相似文献
44.
Proximal digital annular ligament (PDAL) desmitis occurs in horses for which PDAL desmotomy is the only reported treatment. The presented work aims to develop a technique for safely performing PDAL desmotomy in horses. Twenty hind limbs and 13 forelimbs, harvested from horses dead or euthanized for reasons unrelated to any structure in the pastern region, were used. All horses were free of disease at the level of their PDAL. Proximal digital annular ligament desmotomy was performed using a minimally invasive approach to the digital flexor tendon sheath between the palmar (plantar) annular ligament and the PDAL, using a medial or a lateral access. Limbs were immediately dissected after the procedure to assess the completeness of the PDAL desmotomy and any possible damage to surrounding structures. The PDAL was successfully transected in all limbs except one. Damage to the surrounding tissue included transection of the palmar digital nerve (n = 1), longitudinal tear of the superficial digital flexor tendon (n = 3), and transection of the ligament of the ergot (n = 21). A medial approach was found to be safer than a lateral approach. In conclusion, PDAL desmotomy can be performed in a safe, repeatable, and technically easy way. This is, to our knowledge, the first report of a standardized technique for performing a PDAL desmotomy in the horse. 相似文献
45.
Left dorsal displacement of the large colon is a condition unique to the horse that results in an obstruction of the colon and signs of colic. This condition may be successfully treated medically with analgesia, i.v. or oral fluids and feed restriction, exercise with or without administration of phenylephrine, or rolling under general anaesthesia with or without administration of phenylephrine, or a combination of these conservative options. Surgical correction via standing left flank laparotomy or, more commonly, ventral midline laparotomy under general anaesthesia, is required in cases where conservative therapy is unsuccessful. Recurrence rates range from 3.2% to 21%. Surgical attempts to prevent recurrence of this condition include large colon resection, colopexy, and ablation of the nephrosplenic space. 相似文献
46.
Gonadal reproductive and metabolic proteins of male abalone Haliotis laevigata (Donovan, 1808) assessed by targeted mass spectrometry after artificial induction of spawning 下载免费PDF全文
47.
Brett Albanese Thomas Litts Mieko Camp Deborah A. Weiler 《Ecology of Freshwater Fish》2014,23(3):347-359
The goldline darter (Percina aurolineata) is threatened by recent increases in urbanisation in the Coosawattee River watershed, but no studies have addressed their current status. Similarly, limited data on habitat use make it difficult to understand factors that may impact this species. We compared occurrence data before (1996–2000) and after (2009–2011) a period of rapid development and population growth within the watershed. Single‐season occupancy models were built to account for imperfect species detection and to identify habitat covariates. MaxEnt was used to identify important stream reaches for conservation and to understand landscape scale factors correlated with the distribution of goldline darters. Our results indicate a high proportion of sites occupied upstream of Carters Lake during the historic and recent time periods, with no evidence of decline. However, occurrences of goldline darters for sites in Talking Rock Creek and the lower Coosawattee River were sparse in the historic period and absent during the recent period. The probability of detecting goldline darters is low and was positively associated with the occurrence of small substrate. Species distribution models were strongly influenced by watershed area and elevation and indicated a high probability of suitable habitat within the Coosawattee River and large tributaries upstream of Carters Lake. While goldline darter occupancy is currently stable upstream of Carters Lake, continued urbanisation is a threat to long‐term persistence. We recommend additional monitoring and describe a protocol that allows for precise estimates of species occupancy while minimising the risk of sampling‐related mortality. 相似文献
48.
The Reference Watershed Approach (RWA) is used in TMDL development for biological and other impairments with narrative water quality criteria. The questions addressed in this research include: (1) With the RWA, how do land use classifications from different data sources (Digital Ortho-Quarter Quads (DOQQ) and National Land Cover Dataset (NLCD)) impact simulated pollutant loadings? (2) With the RWA, what is the impact of alternative water quality models (GWLF and SWAT) on pollutant loadings? (3) With the RWA, how sensitive are simulated pollutant loadings to the use of different reference watersheds? Various combinations of land use, water quality model, and reference watershed resulted in pollutant reductions that ranged from ?13 to 88%. In a comparison of the use of NLCD versus DOQQ-based land use data with the GWLF model, differences in required reductions ranged from 13 to 74% for three different reference watersheds. Use of alternative water quality models with DOQQ land use data resulted in differences in required sediment reductions from ?43 to 8% for the three reference watersheds. Differences in load reduction requirements were also seen when different reference watersheds were used, regardless of the water quality model or the land use source used. With DOQQ land use, required sediment reductions ranged from 18 to 88% and 37 to 82%, for the SWAT and GWLF models, respectively. These results suggest that explicit margins of safety used to account for modeling uncertainties during TMDL development may need to be substantially greater than 20% when using the reference watershed approach. 相似文献
49.
岷江百合ISSR-PCR反应体系的优化 总被引:2,自引:0,他引:2
以岷江百合为材料,对影响ISSR-PCR反应的主要参数进行优化,建立了适用于岷江百合的ISSR-PCR反应体系.20μL反应体系中,内含1×PCR buffer、1.25 mmol/L Mg2 、0.4 mmol/L dNTPs、0.6 μmol/L引物、0.5 U Taq DNA聚合酶、20ng模板DNA.扩增程序为:94℃预变性5min;94℃变性40 s,52.8℃退火45 s,72℃延伸1min 30s,共45个循环;最后72℃延伸8 min.该优化系统的建立为今后利用ISSR标记技术开展岷江百合遗传多样性研究奠定了基础. 相似文献
50.
L. Marconato C. Leo R. Girelli S. Salvi F. Abramo G. Bettini S. Comazzi P. Nardi F. Albanese E. Zini 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(3):564-569
Background: Increased cancer rates have been documented in people residing in areas around Naples characterized by illegal dumping and incineration of waste.
Hypothesis: Risk of cancer in dogs and cats is associated with waste management.
Animals: Four hundred and fifty-three dogs and cats with cancer and 1,554 cancer-free animals.
Methods: Hospital-based case-control study in Naples (low danger) and nearby cities having a history of illegal waste dumping (high danger). Odds ratio (OR) between high- and low-danger areas was calculated for all tumors and various malignancies in dogs and cats.
Results: An increased risk for cancer development was identified in dogs but not in cats residing in high-danger areas (OR: 1.55; 95% confidence interval: 1.18–2.03; P < .01). A 2.39-fold increased risk of lymphoma ( P < .01) accounted for the greater tumor frequency in dogs residing in high-danger areas. The risk of mast cell tumor and mammary cancer did not differ in dogs residing in high- or low-danger areas.
Conclusions and Clinical Importance: Waste emission from illegal dumping sites increases cancer risk in dogs residing in high-danger areas. An increased prevalence of lymphoma has been previously recognized in humans living close to illegal waste dumps. Thus, epidemiological studies of spontaneous tumors in dogs might suggest a role for environmental factors in canine and human carcinogenesis and can predict health hazards for humans. 相似文献
Hypothesis: Risk of cancer in dogs and cats is associated with waste management.
Animals: Four hundred and fifty-three dogs and cats with cancer and 1,554 cancer-free animals.
Methods: Hospital-based case-control study in Naples (low danger) and nearby cities having a history of illegal waste dumping (high danger). Odds ratio (OR) between high- and low-danger areas was calculated for all tumors and various malignancies in dogs and cats.
Results: An increased risk for cancer development was identified in dogs but not in cats residing in high-danger areas (OR: 1.55; 95% confidence interval: 1.18–2.03; P < .01). A 2.39-fold increased risk of lymphoma ( P < .01) accounted for the greater tumor frequency in dogs residing in high-danger areas. The risk of mast cell tumor and mammary cancer did not differ in dogs residing in high- or low-danger areas.
Conclusions and Clinical Importance: Waste emission from illegal dumping sites increases cancer risk in dogs residing in high-danger areas. An increased prevalence of lymphoma has been previously recognized in humans living close to illegal waste dumps. Thus, epidemiological studies of spontaneous tumors in dogs might suggest a role for environmental factors in canine and human carcinogenesis and can predict health hazards for humans. 相似文献