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BACKGROUND: Giardia spp. and Cryptosporidium spp. are common intestinal protozoan parasites in domestic cats. Few studies have critically evaluated the performance characteristics of commercially available immunoassays for detection of these organisms in the cat. HYPOTHESIS: Human-based immunoassays are suboptimal for the detection of Giardia spp. and Cryptosporidium spp. in cats. ANIMALS: Three-hundred-and-forty-four cats with diarrheic and nondiarrheic fecal specimens at 4 northern California animal shelters. METHODS: A fecal specimen was collected from each cat in a case-controlled fashion. Fecal specimens were tested for Giardia spp. and Cryptosporidium spp. by using centrifugation flotation and 5 commercially available immunoassays (SNAP Giardia, ProSpecT Giardia Microplate Assay, ProSpecT Cryptosporidium Microplate Assay, ImmunoCard STAT! Cryptosporidium/ Giardia Rapid Assay, and Xpect Giardia/Cryptosporidium). Results were compared with a reference standard, the MeriFluor direct immunofluorescence assay. RESULTS: Overall prevalences of Giardia spp. and Cryptosporidium spp. were 9.8 and 4.7%, respectively. The ProSpecT Microplate Assay had the highest sensitivities and specificities for Giardia spp. (91.2 and 99.4%) and Cryptosporidum spp. (71.4 and 96.7%), respectively. The SNAP Giardia antigen assay was easier to use and equally sensitive (85.3%) and specific (100%) to fecal flotation. CONCLUSIONS AND CLINICAL IMPORTANCE: Caution should be exercised when using human-based immunoassays for the diagnosis of Giardia and Cryptosporidium spp. in cats. Fecal flotation remains a useful method for detection of Giardia spp., can be used to detect other parasites, and has a sensitivity of 97.8% for detection of Giardia spp. when combined with the SNAP Giardia immunoassay.  相似文献   
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Tegaserod, a serotonin agonist, has been shown to have prokinetic effects in horses, but pharmacokinetic information is not currently available. The pharmacokinetics and in vitro effects of tegaserod were evaluated. Tegaserod increased the contractile activity of smooth muscle preparations of the equine pelvic flexure. Pertinent pharmacokinetic parameters for a single IV and oral dose were determined. Therapeutic plasma concentrations of tegaserod were achieved by a single oral dose at 0.27 mg/kg. These findings indicate that further clinical studies are warranted to investigate potential benefits in cases of functional gastrointestinal motility disorders in horses.  相似文献   
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REASONS FOR PERFORMING STUDY: In order to evaluate its potential as an adjunct to inhalant anaesthesia in horses, the pharmacokinetics of fentanyl must first be determined. OBJECTIVES: To describe the pharmacokinetics of fentanyl and its metabolite, N-[1-(2-phenethyl-4-piperidinyl)maloanilinic acid (PMA), after i.v. administration of a single dose to horses that were awake in Treatment 1 and anaesthetised with isoflurane in Treatment 2. METHODS: A balanced crossover design was used (n = 4/group). During Treatment 1, horses received a single dose of fentanyl (4 microg/kg bwt, i.v.) and during Treatment 2, they were anaesthetised with isoflurane and maintained at 1.2 x minimum alveolar anaesthetic concentration. After a 30 min equilibration period, a single dose of fentanyl (4 microg/kg bwt, i.v.) was administered to each horse. Plasma fentanyl and PMA concentrations were measured at various time points using liquid chromatography-mass spectrometry. RESULTS: Anaesthesia with isoflurane significantly decreased mean fentanyl clearance (P < 0.05). The fentanyl elimination half-life, in awake and anaesthetised horses, was 1 h and volume of distribution at steady state was 0.37 and 0.26 l/kg bwt, respectively. Anaesthesia with isoflurane also significantly decreased PMA apparent clearance and volume of distribution. The elimination half-life of PMA was 2 and 1.5 h in awake and anaesthetised horses, respectively. CONCLUSIONS AND POTENTIAL RELEVANCE: Pharmacokinetics of fentanyl and PMA in horses were substantially altered in horses anaesthetised with isoflurane. These pharmacokinetic parameters provide information necessary for determination of suitable fentanyl loading and infusion doses in awake and isoflurane-anaesthetised horses.  相似文献   
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Fifty-nine clones (cultivars and advanced selections) ofSolanum tuberosum Group Tuberosum were pollinated with two Group Phureja-haploid Tuberosum hybrids, which produce FDR 2n pollen (ps/ps) and are heterozygous for a dominant gene (Ms/ms) which interacts with Tuberosum cytoplasm to result in male sterility. Twenty-eight and thirty-four plants from each family were transplanted to the field in two different locations, respectively. Pollen samples were collected from each plant and stained with acetocarmine glycerol jelly. Plants with over 95% unstainable pollen were considered male sterile. The families could be put into distinct classes according to the ratio of male sterile to male fertile plants; 3 sterile: 1 fertile (23 clones), 2 sterile: 3 fertile (24 clones), 1 sterile: 5 fertile (3 clones), and 0 sterile: 1 fertile (3 clones). Four families deviated significantly from any expected ratio. The variation for male fertility among families resides in the tetraploid parent, since the male parents have the same genotype (Ms/ms) for theMs locus. The locus of this gene is very distal to the centromere such the 2n gametic output is 1 Ms/Ms : 2 Ms/ms : 1 ms/ms. The variation in male sterility is explained by the presence or absence of a dominant allele of a restorer gene (Rt) in tetraploid Tuberosum. This locus is also very distal to the centromere. The frequency of theRt gene was estimated to be 0.20 in Tuberosum. The finding ofRt gene explains some of the conflicting results in male fertility of haploid Tuberosum x 2x cultivated and wild species hybrids. It also provides an opportunity to partially circumvent this male sterility. Haploids (2n = 2x = 24) extracted from 4x clones withRt genes would have male fertile progeny in crosses with species carrying theMs gene.  相似文献   
258.
Wild diploidSolanum species contain valuable genes for potato improvement, but do not tuberize under the long-day conditions of temperate growing regions. Crosses to haploids (2n=2x=24) of the cultivated potato (Solanum tuberosum) produce hybrids that often tuberize under long days. The objectives of this work are (1) to document high levels of tuberization in haploid-wild species hybrid populations, (2) to evaluate the genetic basis of tuberization in haploid-wild species hybrids grown under long-day conditions, and (3) to propose a genetic model for tuberization in haploid-wild species hybrids. Tuberization under long-day conditions was evaluated in 154 haploid-wild species hybrid families. An average of 68% of plants in these families tuberized. Two major genes exhibiting duplicate dominant epistasis appear to regulate tuberization under long-day conditions. Based on this model, the haploid parent genotypes are A-B-, aaB-, or A-bb, while the wild species are aabb. Future studies are planned to identify the genetic components of tuberization.  相似文献   
259.
European Journal of Plant Pathology - Macrophomina phaseolina is a soil-borne fungal pathogen that incites charcoal rot in more than 500 plant species including melon, Cucumis melo. Disease...  相似文献   
260.
Objective To determine if intraperitoneal (IP) and incisional (SC) lidocaine or bupivacaine provide analgesia following ovariohysterectomy (OHE). Study Design Prospective, randomized, controlled, blinded clinical trial. Animals Thirty dogs presenting to the Veterinary Teaching Hospital for elective OHE. Methods Dogs were pre‐medicated with acepromazine and butorphanol, induced with thiopental and maintained with isoflurane. They were randomly assigned to three groups: 10 received 8.8 mg kg?1 2% lidocaine with epinephrine IP (LID); 10 received 4.4 mg kg?1 0.75% bupivacaine IP (BUP); and 10 received 0.9% saline IP (SAL) upon completion of OHE. All IP doses were standardized to 0.88 mL kg?1 with saline. An additional 2 mL of undiluted solution was placed SC prior to incisional closure. Dogs were scored at 0.5, 1, 2, 3, 6, 8 and 18 hours post‐extubation by one observer. Dogs were evaluated using a visual analogue scale (VAS) for pain and sedation, and a composite pain scale (CPS) that included physiologic and behavioral variables. Dogs were treated with 0.22 mg kg?1 butorphanol + acepromazine if their VAS (pain) score was >50. Parametric variables were analyzed using Student's t‐test or repeated measures anova as appropriate. Non‐parametric variables were analyzed by χ2‐test. Results There were no significant differences in age, weight, incision length, surgery time, anesthesia time, or total thiopental dose among groups. Peak post‐surgical pain scores for all groups occurred at 0.5 hours and returned to baseline by 18 hours. Dogs in the BUP group had significantly lower VAS‐pain scores overall than dogs in the SAL group. Seven out of 10 dogs in the SAL group, 4/10 in the LID group and 2/10 in the BUP group were treated with supplemental acepromazine and butorphanol. No differences between groups were detected with the CPS. No adverse side‐effects were observed. Conclusions and clinical relevance Our findings support the use of IP and SC bupivacaine for post‐operative analgesia following OHE in the dog.  相似文献   
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