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11.
The apparent photosynthetic rate at 70 klux of a leaf attains a peak (33-46 mg CO2-dm-3.hr-1) at a very early stage of its development, decreases rapidly, and then maintains a low constant value (5mg CO2.dm-3.hr-1). The photosynthetic rate is positively correlated with the content of nitrogen, phosphorus, chlorophyll and starch, and is negatively correlated with the content of calcium, manganese, silicon, and moisture. However, the physiological significance of these correlations is doubtful. The photosynthetic potential exceeds the requirement of the sink as a whole plant. The surplus of photosynthates of young, upper leaves is considered to depress the photosynthetic activity of old, lower leaves. This is a conceivable reason for the rapid decline of photosynthetic activity of a leaf with age. A low but constant photosynthetic rate (5mg CO2.dm-3.hr-1) of old leaves at later stages is due, most probably, to a gradual increase in the weight of these leaves. The leaves lower than L6 are considered to be the source for roots, and the photosynthetic rate of these leaves remains higher (10 mg CO2.dm-3.hr-l than the upper leaves. 相似文献
12.
Shunsuke Moriyama Kiyoko Yamaguchi Tomomi Takasawa Hiroaki Chiba Hiroshi Kawauchi 《Fish physiology and biochemistry》2006,32(3):189-201
In an attempt to understand growth regulation in the Japanese eel, Anguilla japonica, we cloned insulin-like growth factor-I (IGF-I) cDNAs and examined their mRNA expression in several tissues. Two eel IGF-I (eIGF-I) cDNAs encoding preprohormones, eIGF-I-Ea1and eIGF-I-Ea2, were cloned from the liver by polymerase chain reaction (PCR). The preproIGF-Is were identical in signal peptide and mature IGF-I, but different in the E domain—eIGF-I-Ea2 mRNA was 36 bp longer than eIGF-I-Ea1 mRNA. Eel IGF-I was 83–94% identical with that of teleosts, 71% identical with that of dogfish, 87% identical with that of bullfrog and chicken, and 83% identical with that of humans. In both males and females the highest eIGF-I-Ea1 mRNA levels were observed in the liver, with detectable levels also found in the gills, heart, stomach, spleen, kidney, intestine, swim-bladder, muscle, and gonads. eIGF-I-Ea1 mRNA levels in the liver were higher in females than in males whereas in the intestine they were lower than in males. eIGF-I-Ea2 mRNA was detected in all the tissues examined and at similar levels in males and females. In this experiment higher eIGF-I-Ea1 mRNA levels were observed in the liver of larger glass eels than in those of smaller fish. eIGF-I-Ea2 mRNA levels were also higher in larger eels, although they were lower than IGF-I-Ea1 mRNA levels. Both eIGF-I mRNA levels in liver were positively correlated with the body size of the␣glass eels. Intraperitoneal injection of recombinant eel GH (reGH), 0.25 μg g−1 body weight, into glass eels resulted in a significant increase in both eIGF-I mRNAs in the liver 1 day after injection compared with control fish, but no elevation was observed 2 days after injection. Incubation of liver slices with reGH at concentrations of 10, 100, and 1,000 ng mL−1 for 24 h resulted in a significant concentration-dependent increase in the levels of both eIGF-I mRNAs. Higher levels of eIGF-I-Ea1 and Ea2 mRNA were observed in the gills ofseawater-reared eels than in those of freshwater-reared fish, but no differenceswere observed in the whole kidney. These results suggest that IGF-I is involved in the regulation of somatic growth and also in adaptation of the Japanese eel to seawater. 相似文献
13.
Naomi NAKAGATA Toru TAKEO Kiyoko FUKUMOTO Yukie HARUGUCHI Tomoko KONDO Yumi TAKESHITA Yuko NAKAMUTA Tomoko UMENO Shuuji TSUCHIYAMA 《The Journal of reproduction and development》2014,60(2):168-171
Sperm cryopreservation has been widely adopted for maintenance of the genetically
engineered mouse (GEM). The cryopreserved sperm are being exchanged among many institutes
worldwide. However, the recipients are not always able to obtain high fertilization rates
with the frozen sperm shipped from senders. In this study, we cryopreserved mouse sperm
via various methods and performed in vitro
fertilization (IVF) in which the combination of methyl-beta-cyclodextrin for sperm
preincubation and reduced glutathione for insemination was used (the MBCD-GSH IVF). In
addition, frozen sperm sent from the Jackson Laboratory (USA) were thawed and used for IVF
in the same manner. The fertilization rates of both the sperm cryopreserved
via the methods applied in some countries and the cryopreserved GEM
sperm improved when used with the MBCD-GSH IVF method. Therefore, we strongly believe that
the MBCD-GSH IVF method brings about relatively high fertilization rates with any strain
of frozen mouse sperm. 相似文献
14.
15.
Muramoto Y Le TQ Phuong LS Nguyen T Nguyen TH Sakai-Tagawa Y Iwatsuki-Horimoto K Horimoto T Kida H Kawaoka Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(5):527-531
Highly pathogenic H5N1 avian influenza A viruses have been spreading among domestic poultry, wild aquatic birds, and humans in many Asian countries since 2003. The largest number of patients, to date, infected with the H5N1 viruses are in Vietnam, where these viruses continue to cause outbreaks in domestic poultry. Here, we molecularly characterized the hemagglutinin and neuraminidase genes of nine H5N1 viruses isolated between January 2004 and August 2005 from domestic poultry in Vietnam. We found that several groups of highly pathogenic H5N1 avian influenza viruses are circulating among these birds, which suggests that H5N1 viruses of different lineages have been introduced into Vietnam multiple times. 相似文献
16.
Effect of nitrite accumulation on nitrous oxide emission and total nitrogen loss during swine manure composting 总被引：3，自引：0，他引：3
The present study investigated the nitrogen balance in swine manure composting to evaluate the effect of nitrite ( ) accumulation, which induces nitrogenous emissions, such as N2 O, during compost maturation. During active composting, most N losses result from NH3 emission, which was 9.5% of the initial total nitrogen (TNinitial ), after which, began to accumulate as only ammonia-oxidizing bacteria proliferated. After active composting, the addition of mature swine compost (MSC), including nitrite-oxidizing bacteria (NOB), could prevent accumulation and reduce N2 O emission by 70% compared with the control in which accumulated as a result of delayed growth of indigenous NOB. Total N2 O emissions in the control and in the treatment of MSC addition (MA) were 9.3% and 3.0% of TNinitial , respectively, whereas N losses as the sum total of NH3 and N2 O over the whole period were 19.0% (control) and 12.8% (MA) of TNinitial , respectively. However, the difference in total N losses was markedly greater than that measured as NH3 and N2 O, which were 27.8% (control) and 13.3% (MA) of TNinitial , respectively. These results demonstrated that the magnitude of nitrogen losses induced by accumulation is too large to ignore in the composting of swine manure. 相似文献
17.
利用抗体法（picoBlueTMImmunscreening Kit,应用B.gibsoni感染血清）从犬吉氏巴贝斯虫（B.gibsoni）裂殖子mRNA制备的吉氏巴贝斯虫cDNA文库中进行免疫筛选,选出目的基因相cDNA片段（阳性克隆）.测序验证后将该cDNA（基因）克隆至原核表达载体pGEX-4T-3,构建重组质粒,在大肠杆菌E.coli（DH5a）中以GST融合蛋白的形式表达（SDS-PAGE分析证明）;表达产物为130kDa的可溶性融合蛋白.免疫学分析（Western blot和ELISA）结果表明,犬吉氏巴贝斯虫重组GST-P130kDa融合蛋白（rBg GST-P130kDa）能与犬吉氏巴贝斯虫（B.gibsoni）感染血清起反应,且与犬巴贝斯虫（B.canis）无交叉反应.本试验利用犬吉氏巴贝斯虫重组BgGST-P130kDa融合蛋白（作为重组抗原）检测巴西（n=310）、日本（n=100）和中国（n=114,n=30）等国随机采集的自然感染狗血清,其结果为巴西狗血清阳性率为55%、日本为8%、中国为1～9%;其结果与间接荧光抗体法（IFAT）结果为一致（作为验证）.结果表明重组BgGST-P130kDa融合蛋白具有较强的免疫原性和特异性,可用于吉氏巴贝斯虫病的诊断,这为吉氏巴贝斯虫病的早期诊断和深入研究犬吉氏巴贝斯虫病的特异性重组抗原及重组疫苗奠定基础. 相似文献
18.
Dai HANAJIMA Kazutaka KURODA Yasuyuki FUKUMOTO Tomoko YASUDA Kazuyoshi SUZUKI Kiyonori HAGA 《Animal Science Journal》2007,78(4):433-439
Numerous reports have accumulated concerning the quality of solid compost. In contrast, there are few for the residue of anaerobic digestion. In this study, the fertilizer value of anaerobic digestion liquor (ADL) was evaluated, and the effect of aeration on the reduction of the phytotoxicity was examined by a germination assay. Low or high aeration (100 or 400 mL/min) was added to 3 L of ADL obtained from a mixture of pig manure and garbage by using 5‐L jar fermenters under a controlled temperature of 30°C. During the 14‐day aeration period, a high aeration rate improved the germination index (GI) score from 5.7% to nearly 80%, while a low aeration rate did not. Although organic matter decomposition, determined as chemical oxygen demand, did not differ with aeration intensity, remarkable differences were observed in the time course of changes in pH, electric conductivity and ammonium‐nitrogen (NH4‐N) and total nitrogen (T‐N) content. Among these parameters, the NH4‐N concentration correlated highly with the GI score (r = 0.986). The primary phytotoxic element in ADL was considered to be NH4‐N, and the stripping of ammonia (NH3) by high aeration resulted in the improvement of the GI score. Although the ratio of major nutrients N : P2O5 : K2O (1:0.41:0.94) in ADL was at nearly same level as conventional liquid fertilizer, special attention should be paid to the high concentration of NH3 when drawing up a fertilization plan. 相似文献
19.
In this study, by partial sequence analysis of the genome segments encoding VP5* and VP7, we characterized a novel bovine group A rotavirus, namely, Tak2, that was detected from adult cattle diarrhea in Tochigi Prefecture, Japan. The nucleotide (nt) and deduced amino acid (aa) sequences of the genome segments encoding VP5* and half of the amino terminal portion of VP7 of Tak2 revealed a low identity with those of group A rotaviruses carrying previously published P and G type specificities (VP5*: nt identity, 61.6%-67.6% and aa identity, 58.0%-71.4%; half of the amino terminal portion of VP7: nt identity, 57.8%-73.5% and aa identity, 61.2%-70.9%). Additionally, phylogenetic analysis of the nt sequences of the genome segments encoding VP5* and half of the amino terminal portion of VP7 revealed that Tak2 formed a branch separate from the established P and G types. These results suggested that Tak2 could possess novel P and G types yet not reported among group A rotaviruses. 相似文献
20.
Anselme SHYAKA Akiko KUSUMOTO Warangkhana CHAISOWWONG Yoshiki OKOUCHI Shinya FUKUMOTO Aya YOSHIMURA Keiko KAWAMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(8):967-972
The prevalence of Campylobacter jejuni in wild birds is a potential hazard for human and animal health. The aim of this study was to establish the prevalence of C. jejuni in wild birds in Tokachi area, Hokkaido, Japan and investigate their virulence in vitro. In total, 173 cloacal swabs from individual wild birds were collected for the detection of Campylobacter spp. Thirty four samples (19.7%) were positive for Campylobacter of which 94.1% (32/34 samples) were C. jejuni. Additionally, one C. coli and one C. fetus were isolated. Seven C. jejuni isolates (one from crows and the other from pigeons) had important virulence genes including all three CDT genes (cdtA, cdtB and cdtC) and flaA, flaB, ciaB and cadF,
and the other isolates were lacking cdtA gene. Further studies on in vitro virulence-associated phenotypes, such as motility assay on soft agar and invasion assay in Caco-2 cells, were performed. The wild bird C. jejuni isolates adhered and invaded human cells. Although the numbers of viable intracellular bacteria of wild bird isolates were lower than a type strain NCTC11168, they persisted at 48-hr and underwent replication in host cells. 相似文献