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101.
Eight new cembranoids, crassarines A-H (1-8) were isolated from the Formosan soft coral Sinularia crassa. Compounds 1-3 represent the rare cembranoids with a 1,12-oxa-bridged tetrahydrofuran ring, while 4 and 5 are the firstly discovered 1,11-oxa-bridged tetrahydropyranocembranoids. The absolute configuration of 6 was determined using the Mosher's method. Compounds 6 and 8 were found to significantly inhibit the expression of both pro-inflammatory iNOS and COX-2 proteins at 10 μM, respectively, while compounds 4-8 were found to be non-cytotoxic toward the selected human liver cancer cells. 相似文献
102.
Chia-Chang Lin Chao-Chiung Huang You-Liang Chen Ching-Wen Lou Chin-Mei Lin Chan-Hung Hsu Jia-Horng Lin 《Fibers and Polymers》2008,9(6):761-767
The energy of impact must decay and be transmitted after a bullet is shot through a ballistic-resistant cloth with a laminate
structure. A rigid net structure transmits the impact stress to reduce the breakage of the material in the direction perpendicular
to the fabric after the impacting of a projectile. This work combines the rigid net structure of stainless steel mesh with
two layers a needle-punched polyamide nonwoven fabric to create a sandwich-like laminate structure. A compound fabric that
is composed of a stainless steel mesh and polyamide nonwoven fabrics is placed in multi-layer Kevlar fabrics, and the buffer
effect is measured by performing a dropping weight impact test and a bullet-shooting test. The specifications of the stainless
steel mesh and the order of placement of the compound fabrics are varied to show the effect of these parameters on the energy
of fracture propagation and the buffer effect of the multi-layered Kevlar compound fabric that includes a layer of compound
fabric that is made of stainless steel mesh and polyamide nonwoven fabrics. In this study, the compound fabric replaces several
layers of Kevlar unidirectional fabric, to be used to reduce the cost of bulletproof vests without reducing ballistic resistance. 相似文献
103.
104.
H Han Hsu 《Veterinary parasitology》1986,21(4):233-245
Radiolabeled metacercariae of Fasciola hepatica were obtained in vivo by incubating infected Lymnaea columella snails with 20 muCi radioselenomethione (75Se-M) per snail in 5 ml of water for 5 h, or in vitro by incubating a batch of unlabeled F. hepatica metacercariae with 75Se-M for 24 h. Radioassay showed that only 5% of the 75Se-M was incorporated into maritas (juvenile flukes) from the in vivo labeled metacercariae. The inner cyst wall of in vivo labeled metacercariae contained 46% of the total activity, of which 21% was dissolved in the excysting medium. The outer, tan-colored cyst wall contained 49% of the radioactivity. Through diffusion/attachment, maritas from in vitro labeled metacercariae could occasionally be labeled with 0.4% of the total radioactivity. However, the activity was lost after inoculation into the body of mice. The outer and inner cyst walls of in vitro labeled metacercariae contained 92% and 7.6%, respectively, of the total activity. Microautoradiography demonstrated that 75Se-M was evenly distributed in the body of marita and the cyst wall of inner and outer layers from an in vivo labeled metacercaria. A 9 X 4 micron rectangularly-shaped aggregate of Ag degree grains was present on the outer periphery of the inner cyst wall. Microautoradiography of in vitro labeled metacercariae demonstrated a significant concentration of Ag degree grains on the cyst walls. The ventral plug contained fewer Ag degree grains per unit area compared to the other portion of the inner cyst wall. Uptake and distribution of 75Se-M in the snail host were also studied. It appeared that rediae and cercariae tended to concentrate the label in the foot, the mantle and the digestive gland. Little or no radioactivity was present in the areas where F. hepatica larvae were not found. 相似文献
105.
W H Hsu 《American journal of veterinary research》1988,49(2):242-244
Xylazine (1.1 mg/kg of body weight, IV), an alpha 2-adrenoreceptor agonist, suppressed the increase in plasma insulin concentration induced by glucose (0.6 g/kg, IV) in dogs. Yohimbine (0.11 mg/kg, IV), an alpha 2-adrenoreceptor antagonist, given 5 minutes after xylazine, reversed effects of xylazine, whereas yohimbine alone increased plasma insulin and decreased plasma glucose concentrations. Seemingly, alpha 2-adrenoreceptors exert a negative control of insulin release. 相似文献
106.
Yi‐Chen Chen Shih‐Chieh Chang Yu‐Han Huang Ya‐Jane Lee Chao‐Chin Chang Jiunn‐Wang Liao Wei‐Li Hsu 《Veterinary and comparative oncology》2019,17(3):427-438
Neutrophil gelatinase‐associated lipocalin (NGAL) is a new biomarker for renal injury. It is also involved in tumorigenesis of different human cancer types. The oncogenic role of NGAL is related to its molecular forms, and heterodimer formation with matrix metalloproteinase 9 (MMP9) promotes human breast cancer (HBC) invasion and metastasis. To date, the levels of NGAL and NGAL/MMP9 complex have not yet been explored in canine mammary tumours (CMTs). Hence, this study aimed to investigate whether NGAL and its molecular forms could be the biomarker for CMT diagnosis. To this end, expression profile of NGAL and MMP9 in mammary epithelial cells as well as in urine samples were detected. By immunohistochemistry staining, NGAL was expressed at variable levels. Unlike HBC, a significant reduction in NGAL expression was demonstrated in benign and malignant CMTs as compared with normal controls. Additionally, NGAL expression was significantly reduced in dogs with metastatic CMTs. By contrast, the mean score of MMP9 expression in ascending order was normal groups, benign, and malignant CMTs. Interestingly, analysis of the molecular form revealed the NGAL/MMP9 complex presents in most mammary tissues and urine of dogs with benign or malignant CMTs, whereas the complex was absent in samples from dogs without CMTs. In conclusion, NGAL and MMP9 are ubiquitously expressed in canine mammary epithelial cells in normal and cancerous status. However, the NGAL/MMP9 complex exclusively presents in mammary tissues and urine of dogs with tumours. 相似文献
107.
Malika Virah-Sawmy Lindsey Gillson Charlie J. Gardner Atholl Anderson Geoffrey Clark Simon Haberle 《Landscape Ecology》2016,31(3):637-654
Context
Integrated conservation decision-making frameworks that help to design or adjust practices that are cognisant of environmental change and adaptation are urgently needed.Objective
We demonstrate how a landscape vulnerability framework combining sensitivity, adaptive capacity, and exposure to climate change framed along two main axes of concern can help to identify potential strategies for conservation and adaptation decision-making, using a landscape in Madagascar’s spiny forest as a case-study.Methods
To apply such a vulnerability landscape assessment, we inferred the sensitivity of habitats using temporal and spatial botanical data-sets, including the use of fossil pollen data and vegetation surveys. For understanding adaptive capacity, we analysed existing spatial maps (reflecting anthropogenic stressors) showing the degree of habitat connectivity, matrix quality and protected area coverage for the different habitats in the landscape. Lastly, for understanding exposures, we used climate change predictions in Madagascar, together with a digital elevation model.Results
The fossil pollen data showed how sensitive arid-adapted species were to past climate changes, especially the conditions between 1000 and 500 cal yr BP. The spatial analysis then helped locate habitats on the two-dimensional axes of concern integrating sensitivity, adaptive capacity and climate change exposure. By identifying resistant, resilient, susceptible, and sensitive habitats to climate change in the landscape under study, we identify very different approaches to integrate conservation and adaptation strategies in contrasting habitats.Conclusion
This framework, illustrated through a case study, provides easy guidance for identifying potential integrated conservation and adaptation strategies, taking into account aspects of climate vulnerability and conservation capacity.108.
F S Hsu R M Chu R C Lee S H Chu 《Journal of the American Veterinary Medical Association》1980,177(7):636-641
Pathologic and viral investigations were done on 13 fetal placentas and 23 aborted fetuses associated with naturally occurring pseudorabies in swine. Of the 13 fetal placentas examined, 7 (53.8%) had various degrees of necrotizing placentitis. The lesions were characterized by coagulative necrosis of the chorionic fossae and by intranuclear inclusions in degenerating trophoblasts and occasionally in mesenchymal cells. In addition, a mild inflammatory cell reaction was observed in the mesenchyma. Numerous viral particles, ultrastructurally indistinguishable from herpesvirus, were observed by electron microscopy in the affected chorionic membrane. Large aggregates of herpesvirus virions were demonstrated in the nucleus and cytoplasm of degenerated trophoblasts and mesenchymal cells. Of the 23 aborted fetuses examined, 22 (95.6%) had typical coagulative necrosis in the liver, spleen, adrenal glands, and visceral lymph nodes. Inclusions similar to those in the chorionic placenta were observed in the parenchymal cells of those organs, on the margins of necrotic areas. Pseudorabies virus was isolated from various organs of the aborted fetuses, but virus isolation from the placentas was not attempted. In a survey of 52 affected sows, sera from 49 (94.2%) neutralized the isolated virus. The findings indicated that the placental lesions caused by the virus were primary. The study also indicated the merit of routine examination of aborted fetal placentas and fetuses for diagnosis of pseudorabies. 相似文献
109.
本試驗是1962年結合生产进行的。結果表明,粮堆中拌合百万分之5的林丹粉剂,以全部拌合防治效果最好;分层或表层拌合的,防治效果较差。无論那种拌合方式都可以有效地防治麦蛾;在原始害虫不多的情况下,对米象、长角谷盜和谷蠹也有良好防治效果,但对防治鋸谷盜和米虱,效果不明显。用百万分之5的林丹粉剂拌合小麦,加工后,林丹的残留量在机制粉中为百万分之1.1—2.5,石磨制粉中为百万分之1.7—3.9,麸皮中为百万分之4.8—10.4。表层拌合的小麦加工成面粉后,为百万分之0.3,麸皮中为百万分之1.2。全部拌合的稻谷加工后,大米及米糠中分別为百万分之0.57—1.0和4.6—12.0,分层拌合的稻谷加工品中則分別为百万分之0.42和2.0。全部拌合的玉米,加工成玉米粉后为百万分之1.9—3.7。上述拌合浓度,对种子发芽率没有影响。 相似文献
110.
Chemical and physical changes required for producing dimensionally stable wood-based composites 总被引:5,自引:1,他引:5
Dr. W. E. Hsu Dr. W. Schwald Mrs. J. Schwald Mr. J. A. Shields 《Wood Science and Technology》1988,22(3):281-289
Summary The springback of compressed wood caused by built-up internal stresses results in excessive thickness swelling of wood-based composites when exposed to moisture. Steam pretreatment can cause partial hydrolysis of hemicellulose for both hardwoods and softwoods which markedly increases the compressibility of wood and in turn significantly reduces the build-up of internal stresses in composites during hot pressing. This steam pretreatment process is a very effective method for producing dimensionally stable wood-based composites. Mild steam pretreatments (e.g. 3 to 4 min at 1.55 MPa) cause a significant reduction of the water insoluble xylan content in hardwoods and the amount of xylan, mannan and galactan in softwoods without any apparent changes in the cellulose or lignin content.The authors wish to thank G. Bastien and B. S. Lethbridge for technical assistance. W. Schwald is grateful to the Fonds zur Förderung der wissenschaftlichen Forschung, Vienna, Austria for granting an Erwin-Schrödinger scholarship (Proj. No. J0128C) 相似文献