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91.
As socio‐environmental problems have proliferated over the past decades, one narrative which has captured the attention of policymakers and scientists has been the need for collaborative research that spans traditional boundaries. Collaboration, it is argued, is imperative for solving these problems. Understanding how collaboration is occurring in practice is important, however, and may help explain the idea space across a field. In an effort to make sense of the shape of fisheries science, here we construct a co‐authorship network of the field, from a data set comprising 73,240 scientific articles, drawn from 50 journals and published between 2000 and 2017. Using a combination of social network analysis and machine learning, the work first maps the global structure of scientific collaboration amongst fisheries scientists at the author, country and institutional levels. Second, it uncovers the hidden subgroups—here country clusters and communities of authors—within the network, detailing also the topical focus, publication outlets and relative impact of the largest fisheries science communities. We find that whilst the fisheries science network is becoming more geographically extensive, it is simultaneously becoming more intensive. The uncovered network exhibits characteristics suggestive of a thin style of collaboration, and groupings that are more regional than they are global. Although likely shaped by an array of overlapping micro‐ and macro‐level factors, the analysis reveals a number of political–economic patterns that merit reflection by both fisheries scientists and policymakers. 相似文献
92.
The objective of this study was to describe the clinical, histologic and immunohistochemical features, the surgical treatment, and outcome of a cataract secondary to persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous (PHTVL/PHPV) in a dog. A 4-month-old male Bloodhound dog presented for evaluation of a cataract. A complete ophthalmic examination and ocular ultrasonography were performed. A resorbing cataract with intralenticular hemorrhage, lens induced uveitis, and PHTVL/PHPV were diagnosed. Extracapsular cataract extraction using phacoemulsification was performed. A primary posterior capsulectomy was performed to remove a retrolental plaque with the posterior capsule; the excised plaque was submitted for histopathology and immunohistochemical staining. A 41-Diopter intraocular lens (IOL) was implanted. Functional vision was maintained postoperatively during the 21-month follow-up period. Histologically, the posterior capsule was coiled and exhibited duplication. The retrolental plaque was comprised of dense fibrous connective tissue, blood vessels, free red blood cells, hemosiderin-laden macrophages, a pocket of neural tissue and numerous perivascular mast cells. With immunohistochemical staining, the neural elements were determined to be glial cells compatible with astrocytes. Cataract secondary to PHTVL/PHPV can be successfully treated using phacoemulsification and planned posterior capsulectomy. Posterior lens capsule duplication, mast cells and astrocytic glial cells may be normal components of the fibrovascular retrolental plaque associated with PHTVL/PHPV. 相似文献
93.
Aragaw K Molla B Muckle A Cole L Wilkie E Poppe C Kleer J Hildebrandt G 《Preventive veterinary medicine》2007,82(3-4):252-261
We looked for Salmonella in all 278 apparently healthy pigs slaughtered between September 2004 and May 2005 at the only pig-slaughtering slaughterhouse in Addis Ababa, Ethiopia. We used standard methods and tested caecal contents, mesenteric lymph nodes, and carcass swabs from each pig (missing only one carcass swab). Of the 278 pigs, 120 (43%) were positive; of the 833 samples 173 (21%) were positive. Thirty-three percent of the isolates were multi-resistant (including 46/48 isolates of S. Hadar, but none of the 39 isolates of S. Eastbourne or of the 37 of S. Saintpaul). Resistance to streptomycin (32.4%), tetracycline (31.8%) and nitrofurantoin (27.2%) was relatively high. The most common pattern of MDR observed was to nitrofurantoin, streptomycin and tetracycline (Resistance type NitStrTet). Our results indicate that salmonellae are prevalent in pigs slaughtered at Addis Ababa abattoir and a large proportion of the isolates were multi-drug resistant. 相似文献
94.
Pasteurella haemolytica cytotoxin neutralizing activity in sera from Ontario beef cattle. 总被引:3,自引:5,他引:3 下载免费PDF全文
A random sample of sera obtained from cattle necropsied as part of the Bruce County Beef Project in 1980-81 was assayed for the ability to neutralize the cytotoxin of Pasteurella haemolytica A1. Cattle dying of fibrinous pneumonia had significantly lower neutralizing activity in serum than cattle which died for reasons other than pneumonia. Activity in pneumonic cattle was also lower than the mean of twelve samples randomly chosen from sera of cattle bled on entry to feedlots in the fall of 1979. A role for the toxin neutralizing response in resistance to pneumonic pasteurellosis is proposed. 相似文献
95.
Intelligence and blood pressure in the aged 总被引:4,自引:0,他引:4
Diastolic hypertension was related to significant intellectual loss over a 10-year period among individuals initially examined in their 60's. Such loss was not found in their age peers in association with normal or mild elevations of blood pressure. Of the subjects initially examined at 70 to 79 years of age, none with hypertension completed the follow-up program, and those with normal and mildly elevated blood pressure showed some intellectual decline over the decade. At the initial examination, hypertension was related to lower intelligence test scores only among those subjects who subsequently did not complete the follow-up program. The results suggest that hypertension is related to intellectual changes among the aged. 相似文献
96.
Antigens of Micropolyspora faeni were located by immunofluorescence in apparent association with alveolar macrophages within sections of lung from cases of bovine interstitial pneumonia. Pretreatment of frozen sections with pH 2.8 glycine-HC1 buffer was a necessary prerequisite for specific staining. Bovine immunoglobulin and bovine complement were identified in similar locations. 相似文献
97.
Combined treatment of ocular squamous cell carcinoma in a horse, using radiofrequency hyperthermia and interstitial 198Au implants 总被引:2,自引:0,他引:2
Unilateral ocular squamous cell carcinoma in a horse was treated effectively with a combination of repeated radiofrequency hyperthermia and interstitial radiotherapy. These 2 modalities of treatment are synergistic. Interstitial irradiation was achieved, using 198Au implants to deliver a total dose of approximately 5,000 rads/implant over an area of 1 cm2. Radio frequency hyperthermia was repeated 3 times, and radiotherapy was used twice. Treatment resulted in complete regression of the tumor, and ocular complications have not been seen. 相似文献
98.
D A Wilkie 《Journal of the American Veterinary Medical Association》1992,200(6):821-824
A silicone subdermal implant was used in the surgical repair of a superior palpebral defect in a horse. The right superior palpebra was missing from the lateral canthus superiorly to the 1 o'clock position, and a corneal ulcer, anterior uveitis, and right micropalpebral fissure also were observed. Lateral canthotomy and canthoplasty were performed to enlarge the palpebral fissure, and a silicone implant was inserted in the superior palpebra to replace the missing tarsal plate. These procedures resulted in a successful reconstruction, with improvement of palpebral function. 相似文献
99.
Partial blockade of beta-adrenergic end-organ response to the autonomic nervous system was effected in a group of older men by administration of propranolol. The result was improved performance in a learning task. The data support the hypothesis that the learning decrement found among older men is not simply a manifestation of structural change in the central nervous system but is, at least in part, associated with the heightened arousal of the autonomic nervous system that accompanies the learning task. 相似文献
100.
Deficient cutaneous response to PHA-P in healthy puppies from a kennel with a high prevalence of demodicosis. 下载免费PDF全文
Intradermal injection of phytohemagglutinin was used to evaluate the integrity of cell-mediated immunological reactions in Doberman puppies thought to be predisposed to demodicosis. Results indicate a statistically significant deficiency of cutaneous delayed response in these dogs when compared with age matched Beagles, adult Dobermans or random control dogs of various ages and breeding. The high prevalence of demodicosis in the kennel of origin may have been due to the observed deficiency of cutaneous immune function. 相似文献