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101.
Northern red oak (Quercus rubra L.) and yellow-poplar (Liriodendron tulipifera L.) were grown for two years in full sunlight (unshaded) or 20% of full sunlight (shaded) under either well-watered or drought conditions. There was a close association between evaporative flux (in situ) and leaf-specific conductivity (LSC) in stem segments of both species. Shaded, drought-stressed seedlings of both species had significantly reduced leaf area, evaporative flux, volume flow rate in xylem, flow velocity, potentially functional xylem area, and LSC than unshaded, well-watered seedlings. Reductions in LSC associated with drought or shade were similar for both species; and within a treatment, both species had similar LSC. Species differed in the manner of LSC adjustment to drought and shade. Reductions in leaf area associated with drought or shade were accompanied primarily by reductions in potentially functional xylem area for L. tulipifera, and by reductions in flow velocity for Q. rubra. These results suggest (1) the existence of a homeostatic balance between evaporative flux and LSC, (2) that species with widely different growth patterns and xylem anatomies may develop similar LSC within the same environment, and (3) a possible hydraulic basis for differences in habitat between ring- and diffuse-porous species. 相似文献
102.
Summary The wettability of four Asian meranti species (dark red, light red, white, and yellow) in various liquids was studied by a cone-immersion technique. Wettability was expressed in terms of the area under the force-immersion curve and referred to as the wettability index. Wettability was strongly influenced by the pH of the solution, generally increasing with increasing pH. Surfactant type affected wettability, with the cationic type yielding the greatest wettability followed by anionic and nonionic types. Among the liquids used, distilled water gave the lowest, and acetone-isopropyl alcohol solution gave the greatest wettability. Of the meranti species, yellow meranti showed the greatest wettability, followed by white, light red, and dark red meranti.A plot of the relative amount of liquid absorbed into the wood sample versus wettability index yielded two regions, one attributed mainly to liquid trapped in crevices on the wood surface, and another which may be more indicative of wood-liquid interactions. A highly significant linear correlation between wettability index and liquid surface tension was found for those species with low and medium wettability, while that with high wettability showed no correlation. A new empirical approach of determining the critical surface tension of wood is discussed. Limited data for the present method indicated close agreement with result from the literature obtained by the use of the well-known Zisman's contact angle approach. 相似文献
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104.
Guardabassi L Schmidt KR Petersen TS Espinosa-Gongora C Moodley A Agersø Y Olsen JE 《Veterinary microbiology》2012,159(3-4):351-353
According to the current taxonomy, the Staphylococcus intermedius group (SIG) comprises of at least three distinct species. While S. intermedius and S. pseudintermedius are associated with specific hosts (pigeons and dogs, respectively), the natural host of S. delphini remains unclear. We analysed 158 SIG isolates from less studied animal species belonging to the order Carnivora, including mink (n=118), fox (n=33), badger (n=6) and ferret (n=1). Species identification was performed by nuc PCR in combination with sodA sequence analysis and pta PCR restriction fragment length polymorphism (RFLP). The results showed a consistent association between host and bacterial species. All isolates from minks, ferret and badgers belonged to S. delphini group A, whereas all fox isolates except one were identified as S. pseudintermedius. The remaining fox isolate belonged to S. delphini group A. The results indicate that Mustelidae such as minks, ferrets and badgers are natural hosts of S. delphini group A. This is in contrast with Canidae, which are primarily colonized and infected with S. pseudintermedius. These findings suggest that coagulase-positive staphylococcal species may have evolved and diverged through host adaptation. 相似文献
105.
Hart ML Suchodolski JS Steiner JM Webb CB 《Journal of Feline Medicine and Surgery》2012,14(4):240-245
This study was designed to test the hypothesis that in cats with chronic diarrhea the daily administration of a proprietary synbiotic (Proviable-DC) would result in an improvement in stool character, as assessed by the owner. Adult cats with chronic diarrhea were recruited for the study and screened for systemic diseases. Fecal flotation, wet mount, immunofluorescence assay (IFA) for Giardia and Cryptosporidium species, and Tritrichomonas species polymerase chain reactions (PCRs) were used to screen for intestinal parasitism. The synbiotic was administered for 21 days; otherwise, no changes were made to ongoing treatment(s) or diet. The severity of the diarrhea was assessed using a standardized fecal scoring system and the owner's subjective perception before, and after, supplementation. The mean fecal score for the 53 cats completing the study decreased from 6.0 to 4.4, representing a significantly (P <0.001) firmer stool character. Seventy-two percent of owners perceived an improvement in their cat's diarrhea following a 21-day course of synbiotic supplementation. 相似文献
106.
Bertagnoli A Räber M Morandi N Mortellaro CM Steiner A 《Veterinary journal (London, England : 1997)》2012,191(1):121-127
The aim of this study was to describe the tenovaginoscopic approach to the bovine common digital flexor tendon sheath (CDFTS). A comparative anatomical, ultrasonographic and endoscopic study was undertaken using 26 healthy cadaver feet from adult dairy cows. Tenovaginoscopy was performed using a rigid, 30° arthroscope (length 18 cm; outer diameter 4mm) enabling a direct view of the synovial cavity and the following structures: digital flexor tendons, digital annular ligaments, lateral and medial pouches, three mesotendons, the vinculum of the superficial digital flexor tendon, and a slot-shaped opening in the manicaflexoria of the hind feet. Additionally, four clinical cases of septic tenosynovitis treated with lavage under tenovaginoscopic control were examined. Tenovaginoscopy represents a feasible, minimally invasive method for the diagnosis and treatment of septic tenosynovitis of the CDFTS, which allows the degree of alterations of the normal structures to be evaluated. 相似文献
107.
Elevated canine pancreatic lipase immunoreactivity concentration in dogs with inflammatory bowel disease is associated with a negative outcome 总被引:1,自引:0,他引:1
A. Kathrani J. M. Steiner J. Suchodolski J. Eastwood H. Syme O. A. Garden † K. Allenspach 《The Journal of small animal practice》2009,50(3):126-132
O bjectives : To investigate whether elevated canine pancreatic lipase immunoreactivity (CPLI) concentrations in dogs with inflammatory bowel disease (IBD) is associated with a worse clinical outcome.
M ethods : Serum CPLI assays were performed on serum stored from cases diagnosed with IBD. Thirty-two dogs with CPLI results within the reference range were designated as the control group and 15 dogs had CPLI above the reference range. Clinical signs, age, serum lipase and amylase activities, serum albumin and cobalamin concentrations, abdominal ultrasound examination, histopathology on small intestinal biopsies, management of IBD and outcome were compared between the two groups.
R esults : No significant differences were found in clinical activity score (P=0·54), number of antibiotic-responsive disease cases (P=0·480), number of steroid-responsive disease cases (P=0·491), serum amylase activity (P=0·058), serum cobalamin concentration (P=0·61), serum albumin concentration (P=0·052), abdominal ultrasound score (P=0·23) and histopathology scores for IBD (P=0·74) between the two groups. Dogs with increased CPLI concentration were significantly older and had a higher serum lipase activity than dogs with a CPLI concentration within the normal reference range (P=0·001, P=0·001, respectively). Moreover, dogs with increased CPLI concentration responded poorly to steroid treatment (P=0·01) and were significantly more likely to be euthanased at follow-up (P=0·02).
C linical S ignificance : CPLI should be measured in cases of canine IBD as elevated CPLI was associated with a worse outcome. 相似文献
M ethods : Serum CPLI assays were performed on serum stored from cases diagnosed with IBD. Thirty-two dogs with CPLI results within the reference range were designated as the control group and 15 dogs had CPLI above the reference range. Clinical signs, age, serum lipase and amylase activities, serum albumin and cobalamin concentrations, abdominal ultrasound examination, histopathology on small intestinal biopsies, management of IBD and outcome were compared between the two groups.
R esults : No significant differences were found in clinical activity score (P=0·54), number of antibiotic-responsive disease cases (P=0·480), number of steroid-responsive disease cases (P=0·491), serum amylase activity (P=0·058), serum cobalamin concentration (P=0·61), serum albumin concentration (P=0·052), abdominal ultrasound score (P=0·23) and histopathology scores for IBD (P=0·74) between the two groups. Dogs with increased CPLI concentration were significantly older and had a higher serum lipase activity than dogs with a CPLI concentration within the normal reference range (P=0·001, P=0·001, respectively). Moreover, dogs with increased CPLI concentration responded poorly to steroid treatment (P=0·01) and were significantly more likely to be euthanased at follow-up (P=0·02).
C linical S ignificance : CPLI should be measured in cases of canine IBD as elevated CPLI was associated with a worse outcome. 相似文献
108.
109.
110.
Westermarck E Skrzypczak T Harmoinen J Steiner JM Ruaux CG Williams DA Eerola E Sundbäck P Rinkinen M 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(2):177-186
Fourteen dogs had shown chronic or intermittent diarrhea for more than 1 year. Diarrhea had been successfully treated with tylosin for at least 6 months but recurred when treatment was withdrawn on at least 2 occasions. Tylosin-responsive diarrhea (TRD) affects typically middle-aged, large-breed dogs and clinical signs indicate that TRD affects both the small and large intestine. Treatment with tylosin eliminated diarrhea in all dogs within 3 days and in most dogs within 24 hours. Tylosin administration controlled diarrhea in all dogs, but after it was discontinued, diarrhea reappeared in 12 (85.7%) of 14 dogs within 30 days. Prednisone given for 3 days did not completely resolve diarrhea. Probiotic Lactobacillus rhamnosus GG did not prevent the relapse of diarrhea in any of 9 dogs so treated. The etiology of TRD, a likely form of antibiotic-responsive diarrhea (ARD) is unclear. The following reasons for chronic diarrhea were excluded or found to be unlikely: parasites, exocrine pancreatic insufficiency, inflammatory bowel disease, small intestinal bacterial overgrowth, enteropathogenic bacteria (Salmonella spp., Campylobacter spp., Yersinia spp., or Lawsoni intracellularis), and Clostridium perfringens enterotoxin and Clostridium difficile A toxin. A possible etiologic factor is a specific enteropathogenic organism that is a common resident in the canine gastrointestinal tract and is sensitive to tylosin but difficult to eradicate. Additional studies are required to identify the specific cause of TRD. 相似文献