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31.
We examined the ability of salmon growth hormone (sGH) in sodium alginate (SA) gel to accelerate the somatic growth of juvenile abalone, Haliotis discus hannai, by feeding. After the feeding of sGH at 50 μg or 100 μg in 350 mg SA gel, immunoreactivity to sGH in body fluid was maximal after 12 h, and was still detectable at 24 h. No immunoreactivity was observed in the control group. Following the feeding of sGH at 0.5 mg or 5 mg/8 g of SA gel at 7- and 14-day intervals, there was a greater increase in shell length and body weight than in the control. In abalone, sGH can be transported from food into the circulatory system and subsequently improve somatic growth.  相似文献   
32.
Under the coastal fisheries co-management regime in Japan, local fishers play important roles in deciding on and implementing local management measures. Therefore, using the case study of a hairtail trolling line fishery, we conducted a transdisciplinary research with fishers, processors, government officers, etc. Taking social and biological factors into account, we defined management criteria and targets (resource, economic, human community, and local food culture) in collaboration with local fishers. We chartered local fishing vessels to determine parameters that were easily understood by local fishers. We established a local consultative committee comprising fishers, processors, and distributors, and developed a fish distribution strategy to nurture the local hairtail food culture. The integrated effects of various management scenarios were evaluated by the operating model. We found that co-ordinated management by both the trolling line fishery and purse seiners in the neighbouring prefecture was required to achieve targets. Two realistic scenarios are recommended: a conservative scenario that could achieve targets even with few strong year classes, and an adaptive scenario that protects strong year classes, but relies on a higher frequency of these. We shared these results with the local fishers and government officers, which led to actual improvements in management measures.  相似文献   
33.
The mutual control of the electric and magnetic properties of a solid is currently of great interest because of the possible application for novel electronic devices. We report on the low-magnetic-field (for example, B values of +/-30 milliteslas) control of the polarization (P) vector in a hexaferrite, Ba2Mg2Fe12O22, which shows the helimagnetic spin structure with the propagation vector k0 parallel to [001]. The B-induced transverse conical spin structure carries the P vector directing perpendicular to both B and k0, in accord with the recently proposed spin-current model. Then, the oscillating or multidirectionally rotating B produces the cyclic displacement current via the flexible handling of the magnetic cone axis.  相似文献   
34.
The amount of heavy metals discharged from daily life was estimated in order to know the origin of the metals contained in the sewage sludge which is produced in the wastewater treatment plant treating only domestic wastewater. The amounts of the metals discharged from our daily life were estimated to be in the range of 0.2 to 0.3 for Cd, 1.6 to 1.9 for Ni, 3.5 to 6.8 for Pb, 0.8 to 1.4 for Cr, 8.2 to 19.3 for Mn 9.4 to 55.8 for Cu, 44.3 to 62.7 for Zn and 111 to 293 for Fe in mg.d–1 per person, Using these data, the cycle of the metals in our daily life was discussed in relation to land application of sewage sludge.  相似文献   
35.
Precipitation chemistry in Japan was discussed on a wet-only sample database obtained in a nationwide survey from April 1989 to March 1993. Wet-only samples were collected at 29 stations over Japan on a biweekly basis. Commonly determined chemical parameters were measured in laboratories. The volume-weighted annual mean pH at each site ranged from 4.50 to 5.83 with a mean of 4.76. Concentration ranges and means (parenthesized) on an equivalent basis for major ions were as follows: nss-SO4 2–; 5.2–58.9 (38.6), NO3 ; 1.8–25.0 (14.1), NH4 +; 0.55–29.8 (18.3), nss-Ca2+; 2.0–34.5(14.2), Na+; 6.4–275.3 (49.1), Cl; 13.7–322.4 (63.5) eq L–1. Acid-base relationships for Phase-II records were quantitatively discussed in terms of three measures: pH, fractional acidity, and our proposed pAi.  相似文献   
36.
37.
A new method for catheterization of the portal and hepatic veins in cattle by means of the over-the-wire system was investigated to maintain more reliable long-term patency of catheters. Four cattle were used to evaluate the success rate, patency and safety of the procedure. The catheters, coated by urokinase were patent as long as they were in situ. In addition, the introducer was useful to prevent the catheter from being broken. No complications developed during the10 days after the procedure. Two cows were then euthanized. Post mortem findings were minimal. The results of the study reported here are promising, the benefits are significant and there is no apparent disadvantage to its use.  相似文献   
38.
PCR amplification and nucleotide sequencing of the mini-exon gene revealed that four strains isolated from a sloth (Choloepus hoffmanni), a squirrel (Sciurus granatensis) and two sandflies (Lutzomyia hartmanni) in Ecuador were indistinguishable from Endotrypanum monterogeii. Another strain isolated from Lu. hartmanni showed the high sequence similarity to E. schaudinni. Since three of these strains have been previously identified as Leishmania (Viannia) equatorensis, the results demonstrate that L. (V.) equatorensis is genetically closely related to the genus Endotrypanum. The present study also indicates that Endotrypanum species are distributed in arboreal animals and sandflies in Ecuador, and that mini-exon gene amplification is useful for epidemiological studies of Leishmania and Endotrypanum in the New World.  相似文献   
39.
To determine the effects of propofol and sevoflurane on hemodynamics, acid-base balance and uterine activity in pregnant animals, a prospective experimental study was designed by use of ten pregnant goats. Propofol was intravenously administered at a bolus dose of 5 mg/kg and then infused a rate of 0.3 mg/kg/min for 5 min. Following the induction, the animals were incrementally inhaled 2.7 and 4.1% of end-tidal concentration of sevoflurane each for 30 min, and then recovered. The maternal and fetal heart rate (HR), arterial blood pressure (BP) and acid-base balance, the intrauterine pressure (IUP), and the uterine blood flow (UBF) were measured. Following the pre-anesthetic data, the parameters were measured 7 times throughout the anesthetic and recovering periods. The propofol infusion induced 1.37 times of HR increase and produced decrease in PO(2) and a relevant metabolic acidemia in the mother, with no effect in the fetus. Sevoflurane reduced BP in the fetus from 30 (2.7%) to 60 (4.1%) min of inhalation. The uterine contractions disappeared throughout sevoflurane inhalation, and then recurred within 15 min after the cessation of sevoflurane. Propofol injection increases HR, and induces a moderate hypoxemia and metabolic acidemia associated with the suppressed ventilation for pregnant goats, with less effect on the fetal hemodinamics. Sevoflurane causes minimal change in maternal hemodynamics, but induces significant hypotension in the fetus and reduction of uterine activity. These data may be useful in making anesthetic choices combined with analgesia for Caesarian section in goats.  相似文献   
40.
Between November 1997 and February 2000, winter migratory waterfowls of several species staying in San-in district, western Japan were surveyed for influenza A virus and paramyxovirus at four stations. A total of 18 influenza A viruses was isolated from 1,404 fecal samples of whistling swans, pintails, mallards, and white-fronted geese. Five different hemagglutinins and eight neuraminidases were identified in the viruses isolated, in 11 different combinations, including H7N8 related to a subtype of a highly pathogenic chicken virus. In 2000, five lentogenic (non-pathogenic) Newcastle disease viruses were also isolated from white-fronted geese. These results suggested that possible precursor viruses for highly pathogenic avian myxoviruses are still brought into Japan by migratory waterfowls. The results also support the contention that continued surveillance of wild waterfowl population should be an integral part of control policies for these serious poultry diseases.  相似文献   
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