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1.
SUMMARY: Aoshio is hypoxic milky blue-green seawater observed in some eutrophic bays. Previous studies have shown that colloidal sulfur causes the coloration and that the source of aoshio water is attributed to coastal anoxic bottom water. Occurrences of aoshio have been reported in limited areas of coastal seawater, although hypoxic transparent water seems rather universal. Promotion in auto-oxidation of sulfide by metal ions in seawater was investigated to explain the occurrences of aoshio. Artificial seawater containing 10 μM metal ion was assayed for the sulfide oxidation rate. The velocity constant which represents the oxidation rate within the initial 30 min and the amount of reacted sulfide in 2 h were determined by oxygen monitoring and sulfide quantification, respectively. Fe2+ and Cu2+ enhanced the initial 30 min reaction. Fe2+, Fe3+ and Ni2+ increased the amount of reacted sulfide in 2 h, forming whitish turbid water. Seawater from a suspected source of aoshio water was also assayed for the auto-oxidation rate of sulfide. The oxidation rate in water from 12 m depth was 13–19 times higher than the artificial seawater without an addition of heavy metal ions. More than 15% of the oxidation rate in 12 m deep seawater was explained by dissolved iron in the seawater.  相似文献   
2.
Present electron microscopical and immunocytochemistrical studies elucidated some morphological relationship between intercalated duct (ICD) and pancreatic islet cells in the chicken in streptozotocin (STZ) and/or camostat mesilate (CM) administrations. Twenty-one chickens were set into four experimental groups: (1) control group, (2) STZ administration group, (3) CM administration group, and (4) STZ + CM administration group. Cytoplasms of ICD cells stained more strongly with eosin in STZ administration group than other groups, and electron-dense materials and intercalated processes between ICD and islet cells were also increasing in time dependence in STZ administration. Number of pancreatic islet in STZ + CM co-administration was about 3.1 times larger than other groups. Many small sized cells were detected at surrounding area of ICD and they incorporated 5-bromo-2'-deoxyuridine better than other experimental groups. Present morphological data suggested that ICD cells might support some tolerances of pancreatic endocrine cells against toxic substances and also involve in regeneration of new pancreatic islet cells in STZ + CM co-administration.  相似文献   
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We examined factors affecting the vertical distribution of juvenile walleye pollock during “the second critical period” (i.e. the transition period of prey size) in and around Funka Bay, Hokkaido, Japan. During the day, small juveniles (<30 mm) were distributed mainly in shallow, warm, and low-salinity water within the bay, whereas larger ones (≥30 mm) occurred in deeper, cold and saline water. During the night, the large juveniles migrated to shallower depths. Outside the bay, small- and large-sized juveniles were distributed in water masses of similar physical properties during the daytime, whereas during the nighttime, most of the juveniles moved to shallower depth, and some juveniles dived to deeper water mass. Dietary analysis revealed that large juveniles fed on large copepods (≥0.5 mm in body width) more than small juveniles did. The composition of zooplankton in our survey area showed that large-sized copepods often occurred in deeper saline water. From these results, there is a possibility that juvenile pollock inside and outside Funka Bay occupied different water masses preferable for each feeding advantage.  相似文献   
6.

Objective

To compare electrical velocimetry (EV) noninvasive measures of cardiac output (CO) and stroke volume variation (SVV) in dogs undergoing cardiovascular surgery with those obtained with the conventional thermodilution technique using a pulmonary artery catheter.

Study design

Prospective experimental trial.

Animals

Seven adult Beagle dogs with a median weight of 13.6 kg.

Methods

Simultaneous, coupled cardiac index (CI; CO indexed to body surface area) measurements by EV (CIEV) and the reference pulmonary artery catheter thermodilution method (CIPAC) were obtained in seven sevoflurane-anaesthetized, mechanically ventilated dogs undergoing experimental open-chest cardiovascular surgery for isolated right ventricular failure. Relationships between SVV or central venous pressure (CVP) and stroke volume (SV) were analysed to estimate fluid responsiveness. Haemodynamic data were recorded intraoperatively and before and after fluid challenge.

Results

Bland–Altman analysis of 332 matched sets of CI data revealed an overall bias and precision of – 0.22 ± 0.52 L minute?1 m?2 for CIEV and CIPAC (percentage error: 30.4%). Trend analysis showed a concordance of 88% for CIEV. SVV showed a significant positive correlation (r2 = 0.442, p < 0.0001) with SV changes to a volume loading of 200 mL, but CVP did not (r2 = 0.0002, p = 0.94). Better prediction of SV responsiveness (rise of SV index of ≥ 10%) was observed for SVV (0.74 ± 0.09; p = 0.014) with a significant area under the receiver operating characteristic curve in comparison with CVP (0.53 ± 0.98; p = 0.78), with a cut-off value of 14.5% (60% specificity and 83% sensitivity).

Conclusions and clinical relevance

In dogs undergoing cardiovascular surgery, EV provided accurate CO measurements compared with CIPAC, although its trending ability was poor. Further, SVV by EV, but not CVP, reliably predicted fluid responsiveness during mechanical ventilation in dogs.  相似文献   
7.
The purpose of this study was to assess the role of fleas for transmission of Bartonella species among wild rodents in Japan. Flea samples were collected from wild rodents and examined genetically for Bartonella infection. Bartonella DNA was detected from 16 of 40 (40.0%) flea samples. Sequence analysis demonstrated that 3 of 16 (18.8%) of the Bartonella-positive animals were infested with fleas from which the closely related Bartonella DNA sequence was detected, indicating that the fleas acquired Bartonella from the infested rodents. The DNA was detected in hemolymph, the midgut and the ovary (only in female), indicating that Bartonella might be colonized through the midgut and distributed into the body.  相似文献   
8.
Zinc (Zn) is an essential trace element for DNA synthesis and for cell growth and differentiation. The deficiency induces a wide range of disorders including immunodeficiency. In this study, the influence of Zn deficiency to the mice infected with Babesia microti was examined, and was compared with the influence in the rats infected with B. rodhaini previously reported. Experiments of B. microti infection were conducted using Zn-deficient (ZD; allowed to eat ad libitum on the ZD diet), Zn-adequate (ZA; allowed to eat ad libitum on the ZA diet), and diet-restricted (DR; supplied 2 g/day on the ZA diet) mice. It was suggested that the Zn deficiency exacerbated the infection dynamics of the mice with B. microti by the growth retardation, the reduction of immunity and the decrease in PCV. The results in the mice supported the consequences in the rats previously reported.  相似文献   
9.
Effects of perineural capsaicin (CAPS) treatment on compound action potentials of the superior laryngeal nerve (SLN) afferents were studied in 6 sevoflurane-anesthetized dogs. Perineural CAPS (100 microg/ml) to the bilateral SLNs reduced (P<0.01) the peak and integral amplitudes of the C-wave of the compound action potential. By contrast, the perineural CAPS had no effect on the A-wave component (P>0.05). Removal of the perineural CAPS recovered the C-wave to pretreatment level. The perineural CAPS treatment selectively blocks C-wave compound action potentials of the SLN afferents, providing a useful tool for studies of laryngeal C-fibers in respiratory physiology.  相似文献   
10.
The present study examines whether centroacinar (CA) and intercalated duct (ICD) cells can serve as stem cells, after administration of the diabetogenic agent streptozotocin (STZ). Thirty rats were divided into five experimental groups: (1) control, (2) 1 day after STZ (STZ-1), (3) 3 days after STZ (STZ-3), (4) 7 days after STZ (STZ-7) and (5) 14 days after STZ (STZ-14). Many small pancreatic islets were observed in the STZ-7 group than in the other experimental groups, and many of these small islets were in close contact with ICD and CA cells. A higher number of nestin, insulin-like growth factor-1 (IGF-1) and IGF-1-receptor positive ICD and CA cells were observed at STZ-3 and STZ-7 than at the others. These expression patterns coincided well with the proliferating cell nuclear antigen pattern. The results suggest that rat pancreatic endocrine cells after damage by STZ administration might be recovered from newly generated cells derived from ICD and CA cells.  相似文献   
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