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Cankers and dieback on London plane caused by Diaporthe scabra have been observed in urban plantings in Catania, Italy. Symptoms were delayed spring flush, trunk cankers, small chlorotic leaves associated with dead terminal or lateral branches and an early defoliation. Isolations from infected wood on PDA led to the isolation of the anamorph Phomopsis scabra with α‐conidia production. The infected wood placed in a moist chamber developed pycnidia with α and β conidia and perithecia of the teleomorph D. scabra. Sequence analysis of the internal transcribed spacers ITS1 and ITS2, the ribosomal intragenic spacer beta‐tubulin 1 and beta‐tubulin 2 genes, congruently indicated that the D. scabra isolate is phylogenetically related to two strains of D. helianthi isolated in Italy from sunflower and to strains of D. eres. Inoculations on young plants of London plane growing in pots confirmed the pathogenicity of the isolated fungus. To our knowledge, this is the first report of the disease in Italy.  相似文献   
85.
为了研究厌氧消化过程中日产气量、累计产气量和甲烷含量随厌氧消化时间的变化规律,在中温35℃±1℃条件下,采用批式单相厌氧消化工艺,分别用香菇、杏鲍菇和平菇废弃菌棒与猪粪混合发酵。结果表明,蘑菇菌棒具有很好的产气潜力,其中香菇菌棒TS产气量最高,为142.9mL.g-1,平均产气量664.1mL.d-1,杏鲍菇菌棒所产气体甲烷含量最高,平均63.8%;添加猪粪调节蘑菇菌棒C/N至25/1,对香菇菌棒前期严重酸化现象起到了很好的缓冲作用,使香菇菌棒、杏鲍菇菌棒和平菇菌棒累计产气量较单一物料分别提高了131.5%、97.9%和79.9%。研究结论为:香菇、杏鲍菇和平菇废弃菌棒均具有良好的产气潜力;添加猪粪能显著提高蘑菇菌棒累计产气量,同时提高香菇菌棒甲烷含量,降低杏鲍菇菌棒甲烷含量,对平菇菌棒甲烷含量影响不大。  相似文献   
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Captive breeding has become an important tool in species conservations programmes, maintaining genetic diversity and restoring wild, endangered populations. In order to improve the reproductive efficiency of captive kept capercaillie, the purpose of the study was to determine the effect of selenium and vitamin E addition to semen extender on sperm characteristic during short‐term storage. Ejaculates collected individually from four capercaillie were divided into two parts, diluted threefold with basic EK extender and EK enriched with 1 mg/ml of organic selenium and 8 mg/ml of vitamin E (EK+Se+E) and stored 24 hr at temp. +4°C. Spermatozoa morphology, motility and motility parameter were evaluated in net, diluted and stored semen samples. Significant (p < .05) differences between individual males were stated in relation to the majority of traits evaluated in the freshly collected semen. Comparing to the fresh semen, a significant (p < .05) decrease in percentage of live sperm in total (by 3.8% points on average) has been observed in samples diluted by EK extender, while in semen diluted with EK+Se+E extender this decrease was lower (1.5%pts on average) and not significant. Also per cent of motile sperm in EK+Se+E extender was higher (p < .05) then in EK (71.6% vs. 58.9%), but taking into account the values of individual males, both extender and male effect on liquid semen storage become apparent. Obtained data allow concluding that selenium and vitamin E addition to EK extender had positive effect on morphology and motility of capercaillie semen stored 24 hr at 4°C and can be recommended for similar studies carried out on other Galliformes species.  相似文献   
87.
A flow cytometric method has been developed for rapid determination of sperm concentration in semen from various mammalian species. * * Patent Pending, Int. Publication Number WO/00/54026.
All cells containing DNA are stained with SYBR‐14 or propidium iodide (PI) and sperm concentration is determined in relation to an internal standard of fluorescent microspheres (beads). Satisfactory staining can be achieved within 2–3 min and the following flow cytometric analysis on the FACSCount AF System rapidly provides the user with a precise and accurate assessment of the sperm concentration. In this study, the FACSCount AF System and Sperm Counting Reagent (BD Biosciences) was compared with microscopic counting using a Bürker–Türk haemocytometer. In addition, sperm concentration was determined using the Corning 254 spectrophotometer which is used routinely by Danish artificial insemination stations for boars. The results show that the agreement between flow cytometry and microscopic counting is very high. The slope for the regression line was 1.12 (SE = 0.03) with an estimated intercept with the Y‐axis of 22 × 106sperm/ml (SE = 10 × 106 sperm/ml) and an estimated error of the model of 10 × 106 sperm/ml. For the spectrophotometer, the slope of the regression line was 1.09 (SE = 0.07) with an estimated intercept of 137 × 106 sperm/ml (SE = 25 × 106 sperm/ml). The average error made by the spectrophotometer was 55 × 106 sperm/ml. In addition, the results obtained using flow cytometry was highly repeatable (CV = 2.7%) in comparison with the spectrophotometric method (CV = 6.3%). These results indicate that the FACSCount AF System is a valuable tool for precise and accurate assessment of sperm concentration in boar semen and that use of this system may lead to production of more uniform insemination doses containing a specific number of sperm per dose.  相似文献   
88.
Beat‐to‐beat variation of heart rate is reflective of autonomic balance and has been used to assess pain and stress in human beings. The purpose of this investigation was to pharmacologically manipulate the autonomic nervous system and to determine the effect of these manipulations on heart rate variability (HRV) in dogs. Four adult male hound dogs (27 ± 1 kg) were used in the investigation. Each dog was given five treatments: Parasympathetic blockade (glycopyrrolate; 0.01 mg kg–1 IV and 0.01 mg kg–1 IM), parasympathetic stimulation (phenylephrine; 0.005 mg kg–1 IV + 0.05 mg kg–1hour–1), sympathetic blockade (propranolol; 0.11 mg kg–1 IV), sympathetic stimulation propranolol; 0.01 μg kg–1 minute–1), and saline control. At least 48 hours were allowed between treatments. ECG recordings were obtained using an ambulatory ECG monitor. A 5‐minutes period of continuous recording obtained ~30 minutes after initiation of drug administration was used for data analysis. Changes in HRV were evaluated by time and frequency‐domain analysis. The standard deviation of normal R‐R intervals (SDNN), as well as the standard deviation of successive differences in RR intervals (SDSD) were assessed for each treatment. Low frequency (LFP; 0.05–0.15 Hz), high frequency (HFP; 0.15–0.35 Hz), and total (TP; 0.017–0.5 Hz) spectral power were also determined. The LFP:HFP ratio was also evaluated. A two‐way anova with a Tukey's test was used to detect differences (p < 0.05). Administration of glycopyrrolate or isoproterenol increased HR and decreased SDNN and SDSD below control levels. Phenylephrine or propranolol administration were without effect. LFP was diminished by glycopyrrolate and isoproterenol, but was unaffected by phenylephrine and propranolol. HFP, TP, and LFP:HFP were unaffected by treatment. Both branches of the autonomic nervous system influence SDNN and LFP. SDSD, in contrast, is altered primarily by parasympathetic activity. Thus, it appears that parasympathetic activity modulates HRV in the resting dog, as either withdrawal of parasympathetic influence or accentuated sympathetic activity led to significant changes in these measures of HRV. Conversely, augmentation of parasympathetic activity or withdrawal of sympathetic tone minimally affected HRV.  相似文献   
89.
Evaluation of aqueous tear production in dogs following general anesthesia   总被引:1,自引:0,他引:1  
Pre- and postanesthetic Schirmer tear test (STT) values were measured in 46 dogs. All subjects had normal preanesthetic STT values (18.3 +/- 2.8 mm per min in the left eye [OS] and 18.3 +/- 3.0 mm per min in the right eye [OD]). Significant differences were found between pre- and postanesthetic STT values. Significant decreases in tear production were evident for up to 24 hours following the anesthetic event. Subject age did not significantly influence the results. Duration of anesthesia significantly affected the rate of return to preanesthetic STT values, with anesthetic events greater than two hours in duration having a prolonged effect as compared to anesthetic events less than two hours in duration. Anticholinergic administration prior to or during anesthesia further lowered postanesthetic STT values.  相似文献   
90.
OBJECTIVE: To determine the effect of topical 1% ophthalmic atropine sulfate on intraocular pressure (IOP) in ocular normotensive horses. Animals Studied Eleven clinically healthy horses. Procedures IOP was measured bilaterally twice daily, at 8 AM and 4 PM, for 5 days. No medication was applied for the first 2 days of the study. Thereafter, one eye of each horse was treated with 0.1 mL of topical 1% atropine sulfate ointment twice daily (7 AM and 7 PM) for 3 days. The contralateral eye served as a control. In eight of the horses, an additional IOP reading was taken 3 days following cessation of the atropine treatment. RESULTS: There was no significant difference in the IOP of control vs. treatment eyes in the pretreatment period, days 1 and 2 (P = 0.97 and 0.55, respectively). During the treatment period, treated eyes of 10 of the horses had significantly lower IOP than control eyes (P = 0.03). The mean IOP reduction in treated eyes, relative to untreated eyes, was 11.2%. One horse had a significant rise in IOP in the treated eye compared to the remaining study animals. The IOP of control eyes did not vary significantly over the observation period (P = 0.27). There was no significant variation in IOP between the 8 AM and 4 PM measurement (P = 0.9). CONCLUSIONS: Topical 1% atropine sulfate causes a small, but significant decline in IOP in most ocular normotensive horses. Because topical atropine may elevate IOP in some horses, it should be used with caution in the treatment of glaucoma in this species.  相似文献   
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