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1.
Hrvoje Gomerči Martina Ðuras Gomerči Tomislav Gomerči Hrvoje Luci Merel Dalebout Ana Galov Darinka Škrti Snježana urkovi Snježana Vukovi Ðuro Huber 《European Journal of Wildlife Research》2006,52(3):182-187
The paper describes two stranded ziphiids from Croatia: a subadult female (length 430 cm, body mass 610 kg) that was stranded in 2001 and an adult male (length 510 cm, body mass ∼1,000 kg) that was stranded in 2002. Both were confirmed to be Cuvier’s beaked whales (Ziphius cavirostris Cuvier, 1823) from analysis of mitochondrial DNA sequences and osteological features. There are no previous records of Cuvier’s beaked whales from the Croatian part of the Adriatic. The external shape of the head of the female specimen appears to be significantly different from the heads of Cuvier’s beaked whales from other seas. The Croatian specimen exhibited embedded pieces of gravel in the gum tissue around the tip of the lower and upper jaws, which was observed for the first time in a Cuvier’s beaked whale. The presence of the female in shallow coastal waters for several weeks and her boat-positive behaviour are apparently also first records of this kind for the species. The female was found to have ingested several plastic bags which likely caused her death. These are the northernmost findings of this species in the Adriatic Sea. 相似文献
2.
The histological hallmark feature of Huntington’s disease (HD) and other polyglutamine repeat diseases is the presence of
intracellular inclusions. Much work has been devoted to trying to determine the relationship between inclusion formation and
neuronal injury. However, little attention has been paid to the variability and characteristics of inclusions themselves.
Here, we characterize the morphological and biochemical composition of inclusions in both a transgenic mouse model (R6/2 line)
and an inducible cell culture model of HD (iPC12Q74). We identified several morphologically distinct kinds of inclusions in
different locations (nuclei, cytoplasm and cellular processes). Ubiquitin colocalized completely with all of these inclusions
in both the iPC12Q72 and R6/2 models. In the inclusions in iPC12Q74 cells, the 20S and 11S proteasome subunits colocalized
variably, and the 19S subunit did not colocalize at all. In inclusions in R6/2 mouse neurons, the 20S subunit colocalized
completely, but neither the 11S nor the 19S subunits colocalized at all. While the role of inclusions in the pathogenesis
of HD continues to be debated, we suggest that the content and structure of inclusions vary considerably, not only from cell
to cell but even within individual cells. Their role in the pathogenesis of HD is likely to depend on their location as well
as their composition. 相似文献
3.
Lisa T. Ballance Robert L. Pitman Jay Barlow Todd Pusser Annamaria I. DeAngelis Craig Hayslip Ladd Irvine Debbie Steel C. Scott Baker Daniel Gillies Simone Baumann-Pickering Jennifer S. Trickey Brian Gisborne 《Marine Mammal Science》2024,40(1):123-142
Although Hubbs' beaked whale (Mesoplodon carlhubbsi) was previously known from over 60 strandings on both sides of the North Pacific, it had been identified alive in the wild only once, off Oregon in 1994. In September 2021, we conducted a search effort for beaked whales off the coast of Oregon using a towed hydrophone array and a visual search team. Approximately 350 km off the Columbia River mouth, we detected the vocalizations of an unidentified mesoplodont whale; we stopped our vessel and waited in the area until two unidentified juvenile Mesoplodon surfaced and stayed near our vessel for almost 2 hr. During that time, we took numerous photographs and videos, made behavioral observations, and recorded their vocalizations. The DNA sequence from a biopsy sample identified them as M. carlhubbsi. In this paper, we discuss our biological observations, including color patterning and acquired markings, behavioral observations, and describe for the first time the acoustic characteristics of this species. We confirm that M. carlhubbsi is the source of a previously unidentified acoustic signal known as BW37V, and we update what is known about the at-sea distribution of this species based on previous recordings and observational records. 相似文献
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5.
T. Aran Mooney Paul E. Nachtigall Michelle M. L. Yuen 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2006,192(4):373-380
Toothed whales and dolphins (Odontocetes) are known to echolocate, producing short, broadband clicks and receiving the corresponding echoes, at extremely rapid rates. Auditory evoked potentials (AEP) and broadband click stimuli were used to determine the modulation rate transfer function (MRTF) of a neonate Risso’s dolphin, Grampus griseus, thus estimating the dolphin’s temporal resolution, and quantifying its physiological delay to sound stimuli. The Risso’s dolphin followed sound stimuli up to 1,000 Hz with a second peak response at 500 Hz. A weighted MRTF reflected that the animal followed a broad range of rates from 100 to 1,000 Hz, but beyond 1,250 Hz the animal’s hearing response was simply an onset/offset response. Similar to other mammals, the dolphin’s AEP response to a single stimulus was a series of waves. The delay of the first wave, PI, was 2.76 ms and the duration of the multi-peaked response was 4.13 ms. The MRTF was similar in shape to other marine mammals except that the response delay was among the fastest measured. Results predicted that the Risso’s dolphin should have the ability to follow clicks and echoes while foraging at close range. 相似文献
6.
Extensive epidemiological study implicates that high arsenic content in artesian well water is the causal factor responsible for Blackfoot disease. We determine the arsenic concentration in urine samples of patients with Blackfoot and Bowen’s diseases and examine whether there exists any discrepancy of urinary arsenic concentrations among patients and the normal population. The analyses were made by hydride atomic absorption spectrophotometry (AAS) and the analytical reliability of the method was checked with a standard urine sample (ORTHO Bi-Level Urine Metal Control). The results show that the mean urinary arsenic concentration in 100 healthy adults is 63.4±29.7 μg/L, and those means for 23 and 11 patients with Blackfoot disease and Bowen’s disease are 75.7±39.1 μg/L (P vs controls >0.05) and 201±58 μg/L (P vs controls <0.001), respectively. From the analytical results obtained, we cannot conclude that urinary arsenic is associated with Blackfoot disease, as was disclosed from the epidemiological studies. However, urinary arsenic concentrations are possibly very closely associated with Bowen’s disease. 相似文献
7.
Commerson’s dolphins (Cephalorhynchus commersonii) along the Patagonian coast of South America suffer incidental mortality in fisheries and are the target of a dolphin-watching industry. We describe the daily activity patterns and assess the variation in the relative abundance of the species near the northern boundary of its range. Information was gathered with a spotting scope from a cliff-top vantage point applying the method of scan sampling. Behaviors were categorized as individual feeding, cooperative feeding, directional swimming, socializing, and resting. These behaviors are similar to those observed in other species of small cetacean, but differences were found regarding the patterns of directional swimming and feeding techniques. Hunting tactics favored the association of terns with dolphin groups. No clear dial behavioral pattern was observed, but seasonal changes in the frequency of behaviors were recorded. Group and school sizes were larger during periods with colder sea surface temperature (SST). Seasonal abundance was correlated with SST, suggesting that at higher SST the species forsakes the area, probably in favor of coastal areas to the south with lower SST. 相似文献
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Summary When comparison was made of directions given for three salt solutions commonly used in cell culture preparations and identified
as Dulbecco’s, Earle’s, and Hanks’, variations in composition were found. Some significantly alter the suitability of the
materials for the intended use. Other differences may have less effect. This brief review reveals a tendency among researchers
to follow procedures obtained from colleagues for the preparation of laboratory reagents and media, to cite the original publication
rather than their colleagues’ work as the source of the information, and to fail to compare the two for differences. Some
failures in cell culture propagation may be attributed to similar instances with other published but incorrectly cited work.
Tables are provided that facilitate comparison of the correct original formulations with variants from selected published
sources.
This research was supported by Storrs Agricultural Experiment Station, University of Connecticut, Scientific Contribution
Number 1032. 相似文献
10.
Using animal house experiments we demonstrated that urine odor can elicit physiological changes in the maturation rate of Brandt’s vole (Radde, 1861). We showed that the urine of estrous females, anestrous females and non-breeding males had no effect on the time of sexual maturity of young voles. In contrast, the maturation rate of young female voles was accelerated, and the maturation rate of young male voles was slowed, by exposure to the urine of breeding adult males. Headspace analysis revealed significant differences in the levels of a subset of volatile constituents of urine from breeding and non-breeding males. From a total of 50 components, Propanoic acid, 2,5-Dimethylpyrazine, Dimethyldisulfide, 1-Octene, 1-Hexanol, Hexanoic acid and p-Xylene were observed only in the urine of breeding male Brandt’s voles. All other substances were present in the volatiles from urine of both breeding and non-breeding male Brandt’s vole. 相似文献
11.
《Biomarkers》2013,18(3):212-221
The aromatic amine 4-aminobiphenyl (4-ABP) is present in tobacco smoke. In humans, it is also a known bladder carcinogen. We describe here a method for the quantification of total 4-ABP in urine using capillary gas chromatography/tandem mass spectrometry, with an effective detection limit in urine samples of approximately 0.87 pg/mL. We also examined the efficiency of chemical or enzymatic hydrolysis of urinary aromatic amine metabolites. Although we found acidic or basic hydrolysis effective, we found enzymatic hydrolysis (β-glucuronidase with either Escherichia coli or Helix pomatia) ineffective. As part of this work, we also confirm the presence of N-acetyl-4-ABP and 4-ABP glucuronide in human urine samples from smokers. These metabolites have been reported in animal studies, but previously they have not been identified in human samples. These metabolites, however, were found to be unstable and thus infeasible for biomonitoring. The final validated urinary total 4-ABP assay was applied to the analysis of samples from smokers and nonsmokers, whose status was confirmed from cotinine EIA measurements. Among 41 confirmed nonsmokers, the geometric mean (95% CI) of 4-ABP concentration was 1.64 pg/mg creatinine (1.30–2.07). Conversely, in 89 smokers, the geometric mean of 4-ABP concentration was significantly greater, at 8.69 pg/mg creatinine (7.43–10.16), p?<?0.001. Our results indicate that following tobacco smoke exposure, total urinary 4-ABP is a reliable biomarker for exposure to this carcinogen. 相似文献
12.
Nico Posnien Johannes B. Schinko Sebastian Kittelmann Gregor Bucher 《Arthropod Structure & Development》2010,39(6):399-410
Many questions regarding evolution and ontogeny of the insect head remain open. Likewise, the genetic basis of insect head development is poorly understood. Recently, the investigation of gene expression data and the analysis of patterning gene function have revived interest in insect head development. Here, we argue that the red flour beetle Tribolium castaneum is a well suited model organism to spearhead research with respect to the genetic control of insect head development. We review recent molecular data and discuss its bearing on early development and morphogenesis of the head. We present a novel hypothesis on the ontogenetic origin of insect head sutures and review recent insights into the question on the origin of the labrum. Further, we argue that the study of developmental genes may identify the elusive anterior non-segmental region and present some evidence in favor of its existence. With respect to the question of evolution of patterning we show that the head Anlagen of the fruit fly Drosophila melanogaster and Tribolium differ considerably and we review profound differences of their genetic regulation. Finally, we discuss which insect model species might help us to answer the open questions concerning the genetic regulation of head development and its evolution. 相似文献
13.
The goal of this research was to measure in vitro the inhibitory constants of the antioxidants ascorbic and uric acid in urine, with lucigenin enhanced chemiluminescence (CL)
in Fenton’s system. Maximum CL emission is registered in urine containing H2O2 (5·10−4 M), Fe2+ (5·10−5 M), EDTA (5·10−5 M), and chemical enhancer lucigenin (10−4 M) at pH 5.5 and 36°C. Ascorbic acid exhibits up to 4-fold stronger antioxidant effect than uric acid. The constants of antioxidant
inhibition in urine were measured at concentrations 10−3 and 10−4 M: for ascorbic acid, 5.92 ± 0.04 and 24.05 ± 1.82 μmol·sec−1; for uric acid, 1.60 ± 0.02 and 21.45 ± 0.97 μmol·sec−1, respectively. Three phases of CL kinetics of urine are well observed: spontaneous CL (0–10 sec), fast flash of CL (10–50
sec), and latent period (50–300 sec). The antioxidant efficiency of ascorbic and uric acids in the final stage of catabolic
processes in the body is discussed.
Published in Russian in Biokhimiya, 2006, Vol. 71, No. 8, pp. 1062–1065. 相似文献
14.
Rodrigo Méndez-Alonzo Coral Moctezuma Víctor R. Ordo?ez Guillermo Angeles Armando J. Martínez Jorge López-Portillo 《Annals of botany》2015,115(5):833-840
Background and AimsRhizophora species of mangroves have a conspicuous system of stilt-like roots (rhizophores) that grow from the main stem and resemble flying buttresses. As such, the development of rhizophores can be predicted to be important for the effective transmission of dynamic loads from the top of the tree to the ground, especially where the substrate is unstable, as is often the case in the habitats where Rhizophora species typically grow. This study tests the hypothesis that rhizophore architecture in R. mangle co-varies with their proximity to the main stem, and with stem size and crown position.Methods The allometry and wood mechanical properties of R. mangle (red mangrove) trees growing in a mangrove basin forest within a coastal lagoon in Mexico were compared with those of coexisting, non-buttressed mangrove trees of Avicennia germinans. The anatomy of rhizophores was related to mechanical stress due to crown orientation (static load) and to prevailing winds (dynamic load) at the study site.Key Results Rhizophores buttressed between 10 and 33 % of tree height. There were significant and direct scaling relationships between the number, height and length of rhizophores vs. basal area, tree height and crown area. Wood mechanical resistance was significantly higher in the buttressed R. mangle (modulus of elasticity, MOE = 18·1 ± 2 GPa) than in A. germinans (MOE = 12·1 ± 0·5 GPa). Slenderness ratios (total height/stem diameter) were higher in R. mangle, but there were no interspecies differences in critical buckling height. When in proximity to the main stem, rhizophores had a lower length/height ratio, higher eccentricity and higher xylem/bark and pith proportions. However, there were no directional trends with regard to prevailing winds or tree leaning.Conclusions In comparison with A. germinans, a tree species with wide girth and flare at the base, R. mangle supports a thinner stem of higher mechanical resistance that is stabilized by rhizophores resembling flying buttresses. This provides a unique strategy to increase tree slenderness and height in the typically unstable substrate on which the trees grow, at a site that is subject to frequent storms. 相似文献
15.
Summary The localization and sites of synthesis of -fetoprotein in chick embryos throughout development have been investigated using the combined techniques of immunofluorescence microscopy and tissue culture in the presence of radiolabelled amino acids, followed by immunoautoradiographic analysis.Alpha-fetoprotein is present in a range of embryonic tissues and especially concentrated in the yolk sac, liver and connective tissue. Analysis of culture fluids revealed that the yolk sac is the major site of -fetoprotein synthesis with smaller, but significant quantities being produced by the liver.These results are discussed in relation to mammalian -fetoprotein, and the merits of the chick embryo for studies on the biological function of AFP are considered.Supported by an award from the Science Research Council, to whom grateful acknowledgement is made 相似文献
16.
Dilek Din?ol Ali Arican Arzu Ensari Serdar Akyar Yaar Bedük Abdülkadir Cengiz 《Cancer immunology, immunotherapy : CII》1999,16(2):134-138
A 53-year-old man with triple renal neoplasms in his left kidney presented. He was initially diagnosed intermediate grade
non-Hodgkin’s lymphoma (NHL) which involved gastro-intestinal tract, left kidney, liver and pancreas. He underwent left nefrectomy
because of a persistent renal mass after the completion of chemotherapy. The large renal mass revealed a renal cell carcinoma
(RCC). Additionally, multiple small nodules of non-Hodgkin’s lymphoma and a solitary leiomyoma were observed. 相似文献
17.
A. G. Shiryaev 《Contemporary Problems of Ecology》2013,6(4):381-389
Using the example of a model group of macromycete (clavarioid fungi), a large-scale investigation into the mycological complex of the Eurasian Arctic is conducted. The species composition of clavarioid fungi’s complex is revealed in all longitudinal sectors and latitudinal subzones, and a comparative analysis is carried out. It has been determined that, among groups of aphyllophoroid fungi, the clavarioid life form is the most adapted to the extremally psychrophilic conditions of the Arctic. It is shown that the near-oceanic sectors are the richest, whereas the continental sectors are much poorer. The distribution of the species composition of fungi conforms to the similar distribution of flowering plants, especially hemicryptophytes. The average annual quantity of atmospheric precipitation is the leading climatic factor. The differences make it possible to subdivide the Eurasian Arctic into four mycogeographical regions: Atlantic (European), Siberian, Chukotian (Beringian), and High Arctic. 相似文献
18.
《Animal : an international journal of animal bioscience》2014,8(4):667-674
A retrospective study on seasonal variations in the characteristics of cow’s milk and temperature–humidity index (THI) relationship was conducted on bulk milk data collected from 2003 to 2009. The THI relationship study was carried out on 508 613 bulk milk data items recorded in 3328 dairy farms form the Lombardy region, Italy. Temperature and relative humidity data from 40 weather stations were used to calculate THI. Milk characteristics data referred to somatic cell count (SCC), total bacterial count (TBC), fat percentage (FA%) and protein percentage (PR%). Annual, seasonal and monthly variations in milk composition were evaluated on 656 064 data items recorded in 3727 dairy farms. The model highlighted a significant association between the year, season and month, and the parameters analysed (SCC, TBC, FA%, PR%). The summer season emerged as the most critical season. Of the summer months, July presented the most critical conditions for TBC, FA% and PR%, (52 054±183 655, 3.73%±0.35% and 3.30%±0.15%, respectively), and August presented higher values of SCC (369 503±228 377). Each milk record was linked to THI data calculated at the nearest weather station. The analysis demonstrated a positive correlation between THI and SCC and TBC, and indicated a significant change in the slope at 57.3 and 72.8 maximum THI, respectively. The model demonstrated a negative correlation between THI and FA% and PR% and provided breakpoints in the pattern at 50.2 and 65.2 maximum THI, respectively. The results of this study indicate the presence of critical climatic thresholds for bulk tank milk composition in dairy cows. Such indications could facilitate the adoption of heat management strategies, which may ensure the health and production of dairy cows and limit related economic losses. 相似文献
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20.
《Comparative Biochemistry and Physiology》1963,8(2):95-102
- 1.1. The extraction, separation and quantitative estimation of α-ketoglutaric and pyruvic acids in the blood and urine of the domestic fowl are described.
- 2.2. The concentration of α-ketoglutaric acid in whole blood rose from 0·75 mg/ 100 ml at hatching to 1·53 mg/100 ml at 4 weeks of age. This was followed by a significant fall to 0·94 mg/100 ml at 5 weeks of age and thereafter it remained fairly constant.
- 3.3. The concentration of pyruvic acid in whole blood at hatching was 2·02 mg/100 ml. After an initial fall it rose to a maximum of 2·78 mg/100 ml at 4 weeks of age but thereafter there was a significant fall to the relatively constant level of approximately 1·3 mg/100 ml.
- 4.4. The concentration of pyruvic acid was found to be significantly higher in either the subclavian or jugular venous blood compared with that of heart blood. This was not so for α-ketoglutaric acid.
- 5.5. After 48 hr starvation there was a significant increase in the pyruvic acid content of whole blood. Several other keto-acids also appeared.
- 6.6. α-ketogkutaric acid was found to be the major keto-acid in the urine and accounter for approximately 44 per cent of the total.
- 7.7. These results are compared with values published for other species. 相似文献