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1.
A multiplex polymerase chain reaction (m-PCR) technique was developed as a rapid and accurate diagnostic tool for identifying five major Gram-negative bacilli -Vibrio vulnificus, V. parahaemolyticus, Aeromonas hydrophila, Chryseobacterium meningosepticum and Edwardsiella tarda- that cause major diseases in cultured aquatic animals in Taiwan. The expected amplicons for V. vulnificus, V. parahaemolyticus, A. hydrophila, C. meningosepticum and E. tarda were 410, 368, 685, 180 and 230bp, respectively. The assay was shown to be specific for the target pathogens. The sensitivities of detection were estimated to be 20.5fg~200pg of genomic DNA or 10(2) ~10(4) colony-forming units (cfu) of bacterial isolates when adopted as PCR templates. The m-PCR was capable of simultaneously amplifying target fragments from bacterial genome DNA mixed with the DNA extracted from viscera and tissues taken from fish without affecting the performance of the method.  相似文献   
2.
Mucopolysaccharidosis (MPS) types I and VII are inborn errors of metabolism caused by mutation of enzymes involved in glycosaminoglycan catabolism, which leads to intralysosomal accumulation of glycosaminoglycans. In children, severe forms of MPS I and VII are characterized by somatic and neurologic manifestations, including a poorly understood hearing loss. The purpose of this study is to describe the age-related histopathologic changes of the ear in spontaneous canine models of MPS I and VII. Pathologic changes in the ear were assessed in MPS I and VII dogs ranging from 1.6 to 9.3 months of age. Paraffin-embedded sections of the whole ear and Epon-embedded semithin sections of the cochlea were examined. The following lesions were blindly scored in the middle and inner ear: inflammation, cells vacuolization, thickening of osseous and membranous structures, perivascular vacuolated macrophages infiltration, and bone resorption. All dogs had lysosomal storage within cells of tympanic membrane, ossicles, tympanic bone and mucosa, cochlear bone, spiral ligament, limbus, and stria vascularis. The MPS I dogs mainly had progressive cochlear lesions. The MPS VII dogs had severe and early middle ear lesions, including chronic otitis media and bone resorption. The MPS I dog only partially recapitulates the pathology seen in humans; specifically, the dog model lacks inflammatory middle ear disease. In contrast, the MPS VII dog has severe inflammatory middle ear disease similar to that reported in the human. In conclusion, the canine MPS VII model appears to be a good model to study MPS VII-related deafness.  相似文献   
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4.
The retrogradation of extruded starches from three different botanical sources was studied in concentrated conditions (34 +/- 1% water) at 25 degrees C using differential scanning calorimetry (DSC) and isothermal calorimetry, Fourier transform infrared spectroscopy (FTIR), and wide-angle X-ray scattering. Potato starch showed the highest rate of retrogradation (approximately 0.17 h(-1)) followed by waxy maize (approximately 0.12 h(-1)), while the retrogradation of wheat starch was the slowest (approximately 0.05 h(-1)). In addition to the kinetics, the extent of molecular order in the retrograded samples was studied in detail in terms of "short-range" (helical) and "long-range" (crystalline) distance scales. The amylopectin crystallinity indices were essentially the same (approximately 47-51% amylopectin basis) for the three starches. However, significant differences were found in the enthalpy of melting measured by DSC after "full" retrogradation (potato, 11.6 +/- 0.7; waxy maize, 9.0 +/- 0.5; and wheat, 6.1 +/- 0.3 J/g of amylopectin). The degree of short-range molecular order in the retrograded state determined by FTIR was waxy maize > potato > wheat. The effect of amylopectin average chain length and the polymorphism of the crystalline phase were taken into account to explain the differences in the retrogradation enthalpies.  相似文献   
5.
ABSTRACT

Aims: To compare the effects of intrathecal anaesthesia using procaine and xylazine, with and without sedation with I/V xylazine and butorphanol, on sedation and cardiorespiratory measures in calves undergoing umbilical surgery.

Methods: Male dairy calves, aged <3 months, were recruited that had enlargement of the umbilical stalk which was abnormal when palpated. They were assigned to receive either intrathecal injection between the sixth lumbar and first sacral vertebrae of 4?mg/kg of 2% procaine and 0.2?mg/kg 2% xylazine, with I/V injection of 0.02?mg/kg xylazine and 0.1?mg/kg of butorphanol (IT?+?SED group; n?=?6), or the same intrathecal injection and I/V injection of 0.9% saline (IT group; n?=?7). Surgery to correct abnormalities was carried out with calves positioned in dorsal recumbency. Rescue analgesia with injections of 2% procaine around the surgical wound was administered when movements triggered by surgery were observed. Post-operative analgesia was provided using I/V 0.5?mg/kg meloxicam. Duration of surgery was recorded, as well as degree of sedation, heart rate, systolic (SAP), diastolic (DAP) and mean (MAP) arterial blood pressure during surgery.

Results: All anaesthetic and surgical procedures were successfully performed. Mean total duration of surgery was similar for the IT?+?SED and the IT groups (30.33 (SD 10.09) and 31.00 (SD 10.21) minutes, respectively) (p?=?0.92). All calves were at least mildly sedated from 5 minutes after injections to the end of the surgery. One calf in the IT?+?SED group and three calves in the IT group required rescue analgesia when the umbilicus was manipulated. Between 0 and 10–15 minutes after injection, decreases in mean heart rate, SAP, MAP and DAP were observed in both groups. Mean SAP was lower in the IT?+?SED than the IT group. Hypotension (MAP<60?mm Hg) was present in four calves from the IT?+?SED group and in one from the IT group.

Conclusions and clinical relevance: Intrathecal administration of 2% procaine and 2% xylazine allowed the successful completion of umbilical surgery, but 30% of calves needed rescue analgesia during surgery. Clinically, the addition of I/V sedation seemed to provide better analgesia than intrathecal block alone but resulted in greater hypotension.  相似文献   
6.
Monitoring chemical and physical changes during thermal flavor generation   总被引:1,自引:0,他引:1  
On-line techniques were developed to monitor chemical and physical changes occurring during the heating of skim milk powder (SMP). Atmospheric pressure chemical ionization mass spectrometry (APCIMS) followed the generation and release of volatile compounds from SMP in a packed-bed reactor. Operating conditions were optimized to avoid condensation of high boiling compounds such as maltol, and the system was highly reproducible (CV < 7%). Differential scanning calorimetry (DSC) of SMP identified a potential glass transition at an onset temperature of 67.9 degrees C and a series of exothermic events that were related to different stages of the Maillard reaction. No lactose crystallization was found after heating. Using a heated stage reflectance FTIR device, spectra were obtained at different temperatures. Analysis of the data showed a correlation between the intensity ratio at wavenumbers 1017 and 1064 cm(-1) and the glass transition measured by DSC. This FTIR system was not sensitive enough to detect Maillard intermediates. Combining data from the three techniques provides a fuller picture of the physical changes during the Maillard reaction and their effects on the chemical reactions.  相似文献   
7.
Summary Genetic transformation is vital to the transfer of novel genes into crop plants as well as to the emerging area of functional genomics. However, the successful genetic transformation of wheat still remains time consuming and genotype dependent. This paper updates the progress made in last 3 years towards developing a robust genetic transformation system for wheat. Agrobacterium-mediated wheat transformation offers advantages such as single-copy gene insertion, minimal rearrangement of DNA, low cost and comparatively high efficiency. The reported recent developments in wheat transformation will lead to increased efficiency of wheat breeding programs. The most promising recent progress is in the development of drought-tolerant wheat, since water stress continues to be a major limiting factor hindering world wheat productivity under adverse hot and dry weather conditions.  相似文献   
8.
OBJECTIVE: To assess the impact of a school-based nutrition education intervention aimed at increasing the consumption of fruits and vegetables. DESIGN: The intervention programme increased the provision of fruits and vegetables in schools and provided a range of point-of-purchase marketing materials, newsletters for children and parents, and teacher information. Curriculum materials at age 6-7 and 10-11 years were also developed and utilised. Evaluation was undertaken with groups of younger (aged 6-7 years) and older (aged 10-11 years) children. Methods included 3-day dietary records with interview and cognitive and attitudinal measures at baseline, with follow-up at 9 months, in intervention and control schools. SETTING: The work was undertaken in primary schools in Dundee, Scotland. SUBJECTS: Subjects comprised 511 children in two intervention schools with a further 464 children from two schools acting as controls. RESULTS: Children (n=64) in the intervention schools had an average increase in fruit intake (133+/-1.9 to 183+/-17.0 g day(-1)) that was significantly (P<0.05) greater than the increase (100+/-11.7 to 107+/-14.2 g day(-1)) estimated in children (n=65) in control schools. No other changes in food or nutrient intake were detected. Increases in scores for variables relating to knowledge about fruits and vegetables and subjective norms were also greater in the intervention than in the control group, although taste preferences for fruits and vegetables were unchanged. CONCLUSIONS: It is concluded that a whole school approach to increasing intakes of fruits and vegetables has a modest but significant effect on cognitive and attitudinal variables and on fruit intake.  相似文献   
9.
The effect of gluten on the retrogradation of wheat starch   总被引:1,自引:0,他引:1  
The retrogradation of amylopectin in a wheat starch and a wheat starch/gluten (10:1) blend prepared by extrusion and containing 34% water (wet weight basis) was studied using X-ray diffraction, differential scanning calorimetry and NMR relaxometry during storage at constant water content and temperature (25 °C). For both samples, amylopectin ‘fully’ retrograded after 2–3 days storage, i.e. the different parameters monitored with time to follow the retrogradation had reached their maximum value, and crystallised predominantly into the A polymorph. Under the experimental conditions used, there was no evidence of any significant effects of the presence of gluten on the kinetics, extent or polymorphism of amylopectin retrogradation.  相似文献   
10.
An anatomical study of horse lumbrical muscle (Lm) was carried out by light and electron microscopy in combination with immunochemical and cytochemical methods. Paraffin sections were subjected to haematoxylin and eosin (H & E) and Masson's trichrome staining for morphometric analysis. Paraffin sections were also used for immunostaining by anti-PGP 9.5 for reaction with nerve-protein associated-structures, anti-heat-shock protein 70 (hsp 70) for detection of gene expression changes, anti-fast myosin for the determination of muscle fibre types, and for detection of apoptotic gene expression of muscle fibres by the TUNEL method. The distribution of muscle fibre types on frozen sections was also examined by assaying ATPase (pH 4.2). We found that the proximal end of the tendon of the unipennate-shaped Lm binds to the deep digital flexor tendon, and the distal end of the Lm tendon connects to the medial surface of the palmar annular ligament. The Lm was not always present, but when found it varied in length greatly, up to 8 cm (muscle part alone), and weighed less than 1 g. The Lm was white, pale, or reddish in colour depending on the ratio of muscle fibre and connective tissue contents. The semi-tendinized regressive Lm was composed of rich vasculature, peripheral nerves, and nerve-like organs similar to the neuromuscular spindle (NMS). The extrafusal muscle fibres (e-lm) that surround the NMS were replaced with a thick outer capsule of connective tissues (CT) in the Lm nerve-like organ, which we named the neurotendinous capsule (NTC) organ. NTC organs exist alone or as multiple structures (up to eight) surrounded by a common outer capsule at the outermost CT ring. The NTC possesses several intrafusal muscle fibres (ifm) just as the NMS does. That the ifm was associated with nerve endings was confirmed by anti-PGP 9.5 and electron microscopic observation. Some muscle fibres in ifm and e-lm reacted with anti-fast twitch myosin and with anti-hsp 70. The e-lm exhibited at least two fibre types, determined by ATPase (pH 4.2) assay. The ifm exhibited mainly type I (slow twitch) fibres. No apoptotic gene expression was detected in either ifm or e-lm, suggesting the Lm is a vital organ. The degenerating fibres observed in ifm and e-lm indicate that the turnover rate of cytoplasmic components is accelerated. We attribute this phenomenon to the necessity for adaptation to new environmental demands. The surprising finding of tubular aggregates (TAs) in ifm of the NTC organ suggests that the Lm is continuously adapting. Some results related to variation in diameter of the collagen fibrils, isolation of the NTC organ and the myofibrillar protein constituents are also discussed. In conclusion, the so-called regressive Lm has rich vasculature, many peripheral nerves, and newly described NTC organs. The induction of heat-shock protein, lack of apoptotic gene expression in ifm and e-lm fibres, and TA formation in ifm suggest that horse Lm responds to environmental stress through reorganization and/or remodelling of cell constituents. We hypothesize that the horse Lm has lost its original role as a contractile element and changed to another function, likely as a vital nerve organ.  相似文献   
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