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41.
The interfacial tissue-implant healing reactions have been investigated in the goose to evaluate its suitability as an animal model for joint replacement implant studies. After various implantation periods, geese with one coxofemoral replacement hemiarthroplasty were evaluated for their gait performance and then sacrificed. The implantation sites and femora with implants were subjected to histologic studies, and the interfacial shear strength between the bone and implant was measured. The results were compared with findings reported in the literature on dog and man. Direct bone apposition was found in two geese with a firmly fixed implant. A connective tissue capsule surrounded those seven implant stems that were found to sit loosely in the femoral canal. Whereas the histologic findings were comparable to findings in dog and man, the interfacial shear stress was somewhat lower in the goose. Because of the histopathologically comparable findings of interfacial healing, the goose appears to present a suitable model to study bone implant tissue reactions. Further studies are necessary to determine seasonal-, age-, and sex-related bone tissue differences in the goose.  相似文献   
42.
The aim of this study was to reproduce severe pneumonic lesions, similar to those during naturally-occurring porcine respiratory disease complex, in pigs dually inoculated with porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae at 6 weeks of age, followed by inoculation with porcine circovirus type 2 at two weeks after. Time and sequence of infection with three pathogens mirror Asian field conditions. Microscopically, interstitial pneumonia and peribronchiolar lymphoid hyperplasia are considered the most characteristic lung lesions in infected pigs. The results of the present study demonstrate that inoculation of pigs with these three pathogens can lead to severe interstitial pneumonia with peribronchial or peribronchiolar lymphoid hyperplasia and fibrosis.  相似文献   
43.
Seasonal reproductive and lunar-related spawning cycles of the female honeycomb grouper Epinephelus merra inhabiting Okinawan waters were examined by histological observation of ovaries. Gonadosomatic index (GSI) increased beginning in May and peaked in June. Histological observations revealed that many oocytes laden with yolk were present in the ovaries from May to August. From September to October, ovaries were occupied by immature oocytes. These results suggest that the reproductive season of E.   merra lasts for 4 months from May through August in Okinawan waters. When the fish were collected according to the lunar cycle, GSI increased with the approach of the full moon. Oocytes at various development stages were observed from the first quarter to the full moon. Fresh ovulatory follicles were present in the ovaries around the last quarter moon. These results suggest that E.   merra has a lunar spawning cycle and spawns between the full moon and the last quarter moon. Ovarian features of the fish collected around the last quarter moon were different among individuals; some fish had many oocytes at the tertiary yolk stage in the ovaries, while the ovaries of the others were occupied by the oocytes at the peri-nucleolus and the oil droplet stages. This observation suggests that a minor release of eggs occurs in this species before or after a major spawning lunar day. Oocytes at the migratory nucleus and the maturation stages were not observed in any ovarian samples. This may mean that maturation of oocytes is related to the spawning behavior of this species and makes rapid progress in the process of aggregation at the spawning sites.  相似文献   
44.
Taste-active components in a Vietnamese fish sauce   总被引:7,自引:1,他引:7  
Taste-active components were determined for a typical first-grade Vietnamese fish sauce Nuoc mam , of which total content of extractive compounds reached as high as 20 g/ 100 mL. A complete synthetic extract prepared from 35 compounds according to the analytical data reproduced almost satisfactorily the taste of the original fish sauce. From the synthetic extract, 11 compounds were identified to be the taste-active components by a series of omission and addition tests. The components consisted of glutamic and aspartic acids, threonine, alanine, valine, histidine, proline, tyrosine, cystine, methionine, and pyroglutamic acid. The most effective compound for recreating the characteristic flavor of fish sauce was glutamic acid, followed by pyroglutamic acid and alanine. Many of these components contribute to umami, sweetness, and overall taste of fish sauce. Even though the simplified 11-component extract reproduced the taste of fish sauce, the taste strength was weaker than that of the complete synthetic extract or fish sauce itself.  相似文献   
45.
The objective of the present study was to investigate the effects of corn dried distiller's grains with solubles (DDGS) and enzyme premix (mannanase + phytase) supplementation on the growth performance, carcass and meat quality parameters in finishing pigs. Sixty hybrid pigs (L × LW × D) with initial weight of 63.92 ± 1.50 kg were used in a 3 × 2 factorial design with main effects of DDGS levels (0, 10 and 20%) and enzyme premix levels (0% vs. 0.14%). Average daily gain (ADG, P < 0.01) and average daily feed intake (ADFI, P < 0.05) were decreased due to an increased level of DDGS additive while the feed conversion ratio was improved (P < 0.05) by adding enzyme premix. The diet cost/gain (won/kg) was saved (P < 0.01) due to an increased level of DDGS additive. There were no significant differences in carcass characteristics and meat quality parameters of Longissimus dorsi muscle by DDGS level and enzyme premix. Palmitoleic acid, oleic acid and monounsaturated fatty acid (MUFA) decreased (P < 0.05) according to DDGS level. The results indicate that DDGS may be used in feeds for finishing pig as a replacement of corn and soybean meal without affecting their carcass characteristics and meat quality.  相似文献   
46.
R. F. PARK 《Plant pathology》1990,39(3):416-423
Infection of wheat seedlings by Puccinia striiformis f.sp. tritici was investigated under both laboratory (constant temperature) and field conditions using a 15-h period of 100% r.h. In laboratory studies, infection decreased from 100% at 15 4 C to 0.8% at 20.5 C, and it was estimated that no infection would occur at or above 20.8 + 0.2 C. In contrast, high levels of infection occurred under field conditions even when temperatures fluctuated within the range 19–30°C. Overnight infection experiments conducted at Toowoomba over an 18-month period demonstrated that periods of moisture and temperature favouring infection by P. striiformis f.sp. tritici occurred regularly, even during summer, and that high temperature was a limiting factor on only 3% of the nights tested. This indicates that stripe rust could oversummer readily in this region of the eastern Australian wheat belt, at least in sheltered areas, given a susceptible host. Regression equations relating mean temperature to infection and minimum temperature to infection identified mid to late autumn as an important period in the epidemic development of the disease in this region. The amount of rain recorded during this period was closely associated with subsequent levels of stripe rust observed in commercial crops over the years 1983–87.  相似文献   
47.
This study was performed to evaluate changes in intraocular pressure (IOP) during standard coaxial phacoemulsification using 4 different bottle heights (BHs) and 2 different incision sizes. Coaxial phacoemulsification was performed with a venturi-based machine in 8 enucleated canine eyes through 3.0 and 3.2 mm clear corneal incisions (CCIs). A pressure transducer inserted in the peripheral cornea monitored the IOP in real-time. The surgery was subdivided into 4 stages: sculpt-segment removal, irrigation/aspiration, capsular polishing and viscoelastic removal. The mean IOP and the difference between the maximum and minimum IOPs were calculated at each stage and compared. The ultrasound time and volume of irrigation fluid used were recorded. The mean IOP increased with an elevation in the BH. The mean IOP in the irrigation/aspiration stage was significantly higher than that in the sculpt-segment removal stage at the same BH. The difference between the maximum and minimum IOP at each stage was greater in the 3.2 mm than the 3.0 mm CCIs, although the mean IOP was lower with the 3.2 mm than the 3.0 mm CCIs. The ultrasound time and irrigation fluid volume were greater with the 3.2 mm than the 3.0 mm CCIs. Therefore, fluidic parameters during each stage could be reassessed and adjusted to reduce complications arising from an elevated IOP. Phacoemulsification with 3.0 mm CCIs at a lower BH might lead to less stress on the eye from IOP fluctuations, ultrasound energy and irrigation fluid.  相似文献   
48.
Salmonella Typhimurium strain expressing the Actinobacillus pleuropneumoniae antigens, ApxIA, ApxIIA, ApxIIIA and OmpA, was previously constructed as a vaccine candidate for porcine pleuropneumonia. This strain was a live attenuated (∆lon∆cpxR∆asd)Salmonella as a delivery host and contained a vector containing asd. An immunological study of lymphocyte proliferation, T-lymphocyte subsets and cytokines in the splenocytes of a mouse model was carried out after stimulation with the candidate Salmonella Typhimurium by intranasal inoculation. The splenic lymphocyte proliferation and the levels of IL-4, IL-6 and IL-12 of the inoculated mice were significantly increased, and the T- and B-cell populations were also elevated. Collectively, the candidate may efficiently induce the Th1- and Th2-type immune responses.  相似文献   
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