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961.
Several naturally occurring essential oils including carvacrol, anethole, cinnamaldehyde, cinnamic acid, perillaldehyde, linalool, and p-cymene were evaluated for their effectiveness in reducing decay and increasing antioxidant levels and activities in 'Duke' blueberries ( Vaccinium corymbosum). Carvacrol, anethole, and perillaldehyde showed the capability to promote total anthocyanins and total phenolics and enhance antioxidant activity in fruit tissues expressed as oxygen radical absorbance capacity (ORAC) and hydroxyl radical ( (*)OH) scavenging capacity. All of the essential oils tested in this study were able to inhibit fruit decay development to some degree compared to controls. The most effective compound for mold retardation was p-cymene, followed by linalool, carvacrol, anethole, and perillaldehyde. Cinnamic acid and cinnamaldehyde also suppressed mold growth, but to a lesser extent. Treatment with carvacrol, anethole, or perillaldehyde also significantly increased the levels of fructose, glucose, and citric acid. Individual flavonoids were variably affected by the essential oils. Levels of chlorogenic acid, which was the major phenolic compound in blueberry fruit, were enhanced by all of the essential oils in this study. Increased amounts of quercetin 3-galactoside and quercetin 3-arabinoside were also found in all treated fruit except samples treated with linalool or p-cymene. The major anthocyanin, malvidin 3-galactoside, was enhanced by all essential oils tested except linalool and p-cymene. The levels of other individual anthocyanins including petunidin 3-galactoside, delphinidin 3-galactoside, petunidin 3-glucoside, petunidin 3-arabinoside, delphinidin 3-arabinoside, and cyanidin 3-galactoside were higher in treated fruit compared to controls. Those essential oils that have positive effects on enhancing anthocyanins, phenolic compounds, and antioxidant activity of fruit, but inhibitory effects on microbial growth and decay development, deserve further evaluation.  相似文献   
962.
Comprehensive survey of major rivers in the Tokyo metropolitan area was conducted for clarifying the emission sources of perfluorooctane sulfonate (PFOS) in Tokyo. PFOS was found at all sampling sites at concentrations ranging from 0.5 to 58 ng L?1; in addition to this, it was also indicated that unknown PFOS emission sources are present in the midstream of the Tama River basin. The relationship between PFOS and perfluorooctanoic acid (PFOA) was constant at a ratio of 10:3 (PFOS/PFOA) throughout the Tama River basin. The sum of daily load amounts of PFOS from Tokyo’s major rivers to Tokyo Bay reached 215 g day?1. This value corresponds to 12.8 μg day?1 per person using the sum of wastewater treatment district populations. In contrast, an estimation of PFOS contribution of domestic wastewater was also attempted, and the contribution was 1.6 μg day?1 per person. We took samples up trunk sewers in the Tama River and finally found at the highest PFOS concentration (58,000 ng L?1) from one of the wastewater of the electronic parts manufacturing facilities.  相似文献   
963.
964.
This study was undertaken to investigate the effects of ambient temperature, crude protein levels and their interaction on performance and serum biochemical parameters of broiler chickens. A total of 216 Arbor Acre broiler chickens (108 males and 108 females) were used in a 2 × 3 factorial arrangement and randomly reared at two temperatures (normal temperature: 23 °C; daily cyclic high temperature: 28–32 °C) and fed on three diets with different crude protein levels (153.3, 183.3 or 213.3 g/kg, with constant essential amino acids) from 28 to 42 days of age. Daily cyclic high ambient temperature decreased final body weight, average daily weight gain, average daily feed intake and serum total protein contents (p < 0.001, p < 0.001, p < 0.001, p = 0.008 respectively), but increased feed/gain, mortality, respiratory rate, rectal temperature, serum uric acid contents and serum creatine kinase activity (p = 0.008, p = 0.003, p < 0.0001, p < 0.0001, p < 0.0001, p = 0.003 respectively), irrespective of crude protein levels. At the ambient temperature, reducing crude protein levels resulted in an increase in feed/gain (p < 0.001), but a decrease in serum total protein and uric acid contents. Only serum creatine kinase activity in broiler chickens was interacted by daily cyclic high ambient temperature and dietary crude protein levels (p = 0.003). These results indicated that daily cyclic high ambient temperature had a great effect on performance and serum biochemical parameters in broiler chickens, whereas dietary crude protein levels affected them partially.  相似文献   
965.
为了解决运材岔线存在的问题,提出了汽车运材钢筋混凝土板式轨道(简称板式轨道),其主要组成部分是板块。在板块的设计上应用了平截面板的弯曲理论,在考虑使用寿命和安全度的基础上,按构件破坏的不同阶段分别采用了容许应力法和极限状态法进行了设计,并对二者进行了比较,确定了适于不同车型的板块。通过生产试验,比较了板式轨道与一般的运材线的单位造价,提出了设计施工要求等技术问题,它不仅在技术上可行而且经济上是合理的。  相似文献   
966.
Zoonotic diseases transmitted by arthropods and rodents are a major public health concern in China. However, interventions in recent decades have helped lower the incidence of several diseases despite the country's large, frequently mobile population and socio‐economic challenges. Increasing globalization, rapid urbanization and a warming climate now add to the complexity of disease control and prevention and could challenge China's capacity to respond to threats of emerging and re‐emerging zoonoses. To investigate this notion, face‐to‐face interviews were conducted with 30 infectious disease experts in four cities in China. The case study diseases under discussion were malaria, dengue fever and haemorrhagic fever with renal syndrome, all of which may be influenced by changing meteorological conditions. Data were analysed using standard qualitative techniques. The study participants viewed the current disease prevention and control system favourably and were optimistic about China's capacity to manage climate‐sensitive diseases in the future. Several recommendations emerged from the data including the need to improve health literacy in the population regarding the transmission of infectious diseases and raising awareness of the health impacts of climate change amongst policymakers and health professionals. Participants thought that research capacity could be strengthened and human resources issues for front‐line staff should be addressed. It was considered important that authorities are well prepared in advance for outbreaks such as dengue fever in populous subtropical areas, and a prompt and coordinated response is required when outbreaks occur. Furthermore, health professionals need to remain skilled in the identification of diseases for which incidence is declining, so that re‐emerging or emerging trends can be rapidly identified. Recommendations such as these may be useful in formulating adaptation plans and capacity building for the future control and prevention of climate‐sensitive zoonotic diseases in China and neighbouring countries.  相似文献   
967.
968.
Destruction of cyclin B is required for exit from mitosis and meiosis. A cyclin-specific ubiquitinating system, including anaphase-promoting complex/cyclosome (APC/C) is thought to be responsible for cyclin B destruction. To learn more about the molecular mechanism of cyclin B degradation, a molecular study of the ubiquitinating system in goldfish has been undertaken. For biochemical preparation of APC/C, we first conducted the cloning, sequencing and expression analysis of goldfish, Carassius auratus, cdc27 that encodes a subunit of APC/C from goldfish ovary. The deduced amino acid sequence is highly homologous to cdc27 from other species. Then recombinant goldfish Cdc27CT (C-terminal half of Cdc27) was expressed in Escherichia coli, and an antibody was raised against purified recombinant protein. Polyclonal antiserum cross-reactive with Cdc27 was obtained. By the assay using the antibody, APC/C was purified by column chromatographs.  相似文献   
969.
Activin (AA, AB and BB) is a dimeric protein that belongs to the transforming growth factor- (TGF-) superfamily of growth factors and is involved in the regulation of many physiological and developmental processes. Recently, we have demonstrated that porcine activin stimulated goldfish gonadotropin-II (GTH-II) and growth hormone (GH) secretion from dispersed pituitary cells in static culture and pituitary fragments in perifusion. The action of activin in the goldfish is unique in that it has an acute stimulatory effect on the secretion of GTH-II and GH, whereas in mammals activin usually exhibits long-term stimulatory actions on FSH secretion. The action mechanism of activin is different from that of gonadotropin-releasing hormone (GnRH). Using domain-specific antibodies against mammalian activin subunits, we subsequently demonstrated the existence of immunoreactive activin subunits (A and B) in the goldfish ovary, testis, pituitary and brain, suggesting endocrine, paracrine and autocrine roles for activin in the regulation of goldfish reproduction. Both activin A and B subunits have been cloned from goldfish genome by polymerase chain reaction (PCR). Using the PCR fragments as probes, we have cloned a full length cDNA coding for activin B subunit from the goldfish ovary. Both activin A and B subunits show high homology to those of other vertebrates with the B subunit much more conserved (93 and 98% identity with human and zebrafish B subunit, respectively). The identity of the cloned B subunit was further confirmed by expression in the Chinese hamster ovary (CHO) cells and detection of the specific activity of activin in the culture medium. The messenger RNA of activin B subunit is expressed in a variety of goldfish tissues including ovary, testis, brain, pituitary, kidney and liver, suggesting a wide range of physiological roles for activin in the goldfish. We have also cloned a full length cDNA coding for the activin Type IIB receptor from the goldfish ovary, suggesting that activin may have paracrine or autocrine actions on the ovarian functions. The identity of the cloned receptor was confirmed by specific binding of125 I-activin on COS-1 cells transfected with the cloned Type IIB receptor.  相似文献   
970.
A number of 689 Streptococcus suis isolates collected nationwide from diseased and healthy pigs from 1987 to 1996 were surveyed for antibiotic susceptibilities to 11 drugs. No isolates resistant to amoxicillin, chloramphenicol, and sulfamethoxazole/trimethoprim were found. Isolates were highly susceptible to penicillins (penicillin G, ampicillin, and amoxicillin) except cloxacillin. They were not susceptible to tetracycline, streptomycin, and kanamaycin (MIC90 50 microg/ml, > or = 100 microg/ml, and > or = 100 microg/ml, respectively). Multiple-resistant isolates (> or = 3 antimicrobial agents) were found in 20.3% of all isolates tested.  相似文献   
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