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11.
Mycobacterium avium causes systemic infections through primary intestinal lesions in pigs. However, its pathogenesis is not well understood. The aim of this study was to confirm the effects on swine after enteral infection. One hundred and twelve pigs with hepatic lesions infected with M. avium were used in this study. We investigated the involvement of other organs and the distribution of hepatic lesions in the lobular structure. Most lesions involved the mesenteric lymph nodes. Hepatic lymph nodes were the secondary nodes involved. In 74 cases (66.1%), the hepatic lesions were predominantly distributed in the portal tract of the affected livers. The other 38 cases (33.9%) showed granulomatous lesions in the hepatic lobule. Many cases showed interface hepatitis. There was a significant relationship between focal lesions within hepatic lobule and splenic lesions. These findings suggest that granulomatous lesions formed in hepatic lobules upon establishment of bacteremia in pigs systemically infected with M. avium.  相似文献   
12.
To clarify the process of sex differentiation in protandrous anemone fish, histological structure of their gonads was examined from 1 day to 214 days after hatching (dah). Gonadal development was first characterized by differentiation of ovarian tissues at 61 dah, followed by interspersed appearance of testicular tissues in the ovary at 214 dah.  相似文献   
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14.
Tyrosinase, trypsin, and tryptase are known to play important roles in melanin production of human skin. This paper describes the study of the inhibitory effect of Balanophora fungosa on melanin. The 50% EtOH extract obtained from B. fungosa indicated an inhibitory effect on mushroom tyrosinase activity with an IC(50) value of 15 μg/mL. Bioassay-guided fractionation of the active extract resulted in the isolation of four known compounds. Their structures were identified as 1-O-(E)-caffeoyl-3-O-galloyl-4,6-(S)-HHDP-β-d-glucopyranose (1), 1-O-(E)-caffeoyl-3,4,6-tri-O-galloyl-β-d-glucopyranose (2), caffeoyl-β-d-glucopyranose (3), and abietin (4) on the basis of spectroscopic analyses and comparison of their spectral data with those in the literature. Compounds 1 and 2 prevented pigmentation of melanin in a three-dimensional cultured human skin model. Furthermore, compounds 1 and 2 indicated inhibitory activities against trypsin and tryptase.  相似文献   
15.
We hypothesized that long-term loblolly pine (Pinus taeda L.) land-use restores SOC stock and lability of a subtropical Cambisol to the original levels of the natural forest (NF). Additionally, we hypothesized that roots are the major contributor to SOC and that soil stores most of the ecosystem total carbon (ETC). We investigated a chronosequence of loblolly pine land-use of 17 (first rotation) and 32 years (second rotation, unthinned or thinned) following clearing of the NF. The original SOC stock to 100 cm of NF (209?±?9.4 Mg C ha?1) was depleted by 22% after 17 years of pine, possibly because of intense soil disturbance and low quantity and quality of the residue inputted during the pine stand implementation. However, the SOC stock was restored to the original stock of NF after 32 years of pine, with the input of above and belowground biomass at harvest of the first rotation possibly playing a role in this recovery. Thinning did not affect SOC stocks after 1 year. The POM-C reduced after 17 years and was not recovered after 32 years. We could not ascertain in 5-year evaluation whether root or litter was the major contributor to SOC. Soil held 72% of the ETC in NF and 48–59% in pine plantations, confirming that it stores most of the ETC. Overall, long-term loblolly pine land-use seems to restore the original soil carbon stock in this subtropical site, regardless of some lability losses.  相似文献   
16.
17.
Role of steriod hormones in sex change of protogynous wrasse   总被引:1,自引:0,他引:1  
The endocrine mechanisms of sequential hermaphroditism were investigated in protogynous wrasse, Halichoeres trimaculatus. Administration of aromatase inhibitor and androgen both stimulated sex change, while estrogen suppressed the induced sex inversion. The results suggest that removal of estrogen is a key step to initiate sex change.  相似文献   
18.
A 4-year-old Siberian Husky dog was treated with brown snake antivenom by his regular veterinarian after a witnessed episode of brown snake envenomation. The dog was discharged 5 hours post presentation despite an ongoing coagulopathy. The dog was presented to the emergency centre 2 hours later because the owner believed the dog to be in pain. Initial examination revealed an ambulatory but neurologically normal patient with thoracolumbar pain and laboratory evidence of a coagulopathy. Despite correction of the coagulopathy, the signs progressed to bilateral hind limb paresis after approximately 3 hours of hospitalisation, and continued to deteriorate over the next 56 hours to loss of deep pain perception in the right hind limb. Computed tomography imaging identified the presence of an extradural haematoma which was subsequently removed via a hemilaminectomy. Surgical decompression was successful in treating the spinal compression and the dog recovered with minimal complications. To our knowledge this is the first report of extradural haematoma secondary to coagulopathy induced by brown snake envenomation.  相似文献   
19.

??Context

In the construction sector, wood is facing competition with other materials such as concrete, steel or plastics. Therefore, there is a need for more efficiency in the forest–wood chain by improving silvicutural management and wood processing technologies.

??Aims

The objective of the study is to analyse the influence of log diameter and quality to recovery rate, veneer quality and economic benefit.

??Methods

The trees used in the study came from a 30-year-old Pinus taeda L. thinning trial in Southern Brazil. In total, 57 logs (20.7 to 67.0 cm) were peeled following the standard industrial processing methods of the plywood mill.

??Results

Average recovery rate was 54 % ranging from 35 to 72.6 %, with a linear trend (R 2?=?0.48) of increasing recovery with an increment on the log small-end diameter. Results show that the gap between theoretically possible and real recovery was lower in the logs with bigger diameters, indicating their higher efficiency in industrial processing. Moreover, the economic analysis detected that the current prices for log assortments reflect only the industrial potential of low-quality pruned logs. An optimised pruning strategy would result in higher industrial efficiency, which would allow higher log prices.

??Conclusion

The results indicate that the recovery rate of bigger logs is higher in terms of volume of peeled veneer. The quality and therefore the value obtained from each log were negatively influenced by inadequate pruning strategies. Management of pines for higher value utilisation requires optimized thinning and pruning strategies in order to meet high growth rates and proportionally bigger dimensions of clear wood.  相似文献   
20.
The adult morphology is described and illustrated of Neoplagioporus kajika sp. n. (Digenea: Opecoelidae) found in the Japanese fluvial sculpin Cottus pollux Günther (Osteichthyes: Scorpaeniformes: Cottidae) collected in the Naka River at Terase Bridge, Narutake, Nakagawa Town, Fukuoka Prefecture, Kyushu, Japan. This new species is characterized by that the body shape is oval, that the intestinal caeca end posteriorly at the middle level of the testicular region, that the ovary is trilobed, and that the vitelline follicles are distributed between the pharyngeal level and usually the posterior end of body and fill up the lateral fields of body. The new species is different from three hitherto known Neoplagioporus species, N. zacconis (Yamaguti, 1934) Shimazu, 1990 (type species), N. ayu (Takahashi, 1928) Shimazu, 1990, and N. elongatus (Goto et Ozaki, 1930) Shimazu, 1990, in a combination of these characteristics. The new species is considered mainly infective to C. pollux in the river.  相似文献   
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