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991.
Growth, allometric relationships and sexual dimorphism are described from measurements of 105 male, 149 female and 38 unsexed specimens of short‐beaked common dolphin, Delphinus delphis, stranded along the Irish coastline (53.8% of the sample) or by‐caught in fisheries (46.2% of the sample), from 1990 to 2003. For each dolphin, 24 external body length measurements were recorded. Ages were determined for 183 dolphins by analysis of growth layer groups in the dentine. Males ranged in total body length (TBL) from 105 to 231 cm and females from 93 to 230 cm, with a maximum age of 25 years obtained for both sexes. Using a single Gompertz growth curve, asymptotic values obtained for TBL were 211.6 cm and 197.4 cm for males and females, respectively. Asymptotic lengths were attained at 11 years in males and 9 years in females. The gestation period was estimated to last approximately 11.5 months. Sexual size dimorphism (SSD) was evident, with males being significantly larger than females for 20 of the characters measured, and an SSD ratio of 1.06 was obtained. Sexual shape dimorphism was lacking, except for the presence of prominent postanal humps in mature males. 相似文献
992.
Interannual variations in distribution, size, indices of feeding and condition of juvenile Bristol Bay sockeye salmon Oncorhynchus nerka collected in August to September (2000–2003) during Bering–Aleutian Salmon International Surveys were examined to test possible mechanisms influencing their early marine growth and survival. Juvenile sockeye salmon were mainly distributed within the southern region of the eastern Bering Sea, south of 57°0' N during 2000 and 2001 and farther offshore, south of 58°0' N during 2002 and 2003. In general, juvenile sockeye salmon were significantly larger ( P < 0·05) and had significantly higher indices of condition ( P < 0·05) during 2002 and 2003 than during 2000 and 2001. The feeding index was generally higher for age 1.0 year sockeye salmon than age 2.0 year during all years. Among-year comparisons suggested that Pacific sand lance Ammodytes hexapterus were important components of the juvenile sockeye salmon diet during 2000 and 2001 (20 to 50% of the mean wet mass) and age 0 year walleye pollock Theragra chalcogramma were important components during 2002 and 2003 (50 to 60% of the mean wet mass). Warmer sea temperatures during spring and summer of 2002 and 2003 probably increased productivity on the eastern Bering Sea shelf, enhancing juvenile sockeye salmon growth. 相似文献
993.
A S Brown J M Davis E A Murphy M D Carmichael J A Carson A Ghaffar E P Mayer 《Journal of applied physiology》2007,103(5):1592-1597
Exhaustive exercise has been associated with an increased risk for upper respiratory tract infections in mice and humans. We have previously shown (Brown AS, Davis JM, Murphy AE, Carmichael MD, Ghaffer A, Mayer EP. Med Sci Sports Exerc 36: 1290-1295, 2004) that female mice are better protected from the lethal effects of herpes simplex virus type 1 (HSV-1) infection, both at rest and following exercise stress, but little is known about possible mechanisms. This study tested the effects of estrogen on HSV-1 infection and macrophage antiviral resistance following repeated exhaustive exercise. Female mice were assigned to either exercise (Ex) or control (C): intact female (I-C or I-Ex), ovariectomized female (O-C or O-Ex), or ovariectomized estrogen-supplemented female (E-C or E-Ex). Exercise consisted of treadmill running to volitional fatigue ( approximately 125 min) for 3 consecutive days. Intact female mice had a later time to death than O and E (P < 0.05) and fewer deaths than both O and E (P < 0.05). Exercise stress was associated with increased time to sickness (P < 0.05) and symptom severity at days 6 and 12-21 postinfection (P < 0.05) and decreased macrophage antiviral resistance (P < 0.001) in all groups. E had increased symptom severity at days 6 and 13-21 postinfection (P < 0.05). Results indicate that intact female mice are better protected from the lethal effects of HSV-1 infection and that exercise stress had a similar negative impact in all groups. This protective effect was lost in ovariectomized mice, but it was not reinstated by 17beta-estradiol replacement. This indicates that other ovarian factors, alone or in combination with estrogen, are responsible for the protective effects in females. 相似文献
994.
Effect of Bafilomycin A1 and Nocodazole on Endocytic Transport in HeLa Cells: Implications for Viral Uncoating and Infection 总被引:17,自引:11,他引:6 下载免费PDF全文
Nora Bayer Daniela Schober Elisabeth Prchla Robert F. Murphy Dieter Blaas Renate Fuchs 《Journal of virology》1998,72(12):9645-9655
Bafilomycin A1 (baf), a specific inhibitor of vacuolar proton ATPases, is commonly employed to demonstrate the requirement of low endosomal pH for viral uncoating. However, in certain cell types baf also affects the transport of endocytosed material from early to late endocytic compartments. To characterize the endocytic route in HeLa cells that are frequently used to study early events in viral infection, we used 35S-labeled human rhinovirus serotype 2 (HRV2) together with various fluid-phase markers. These virions are taken up via receptor-mediated endocytosis and undergo a conformational change to C-antigenic particles at a pH of <5.6, resulting in release of the genomic RNA and ultimately in infection (E. Prchla, E. Kuechler, D. Blaas, and R. Fuchs, J. Virol. 68:3713–3723, 1994). As revealed by fluorescence microscopy and subcellular fractionation of microsomes by free-flow electrophoresis (FFE), baf arrests the transport of all markers in early endosomes. In contrast, the microtubule-disrupting agent nocodazole was found to inhibit transport by accumulating marker in endosomal carrier vesicles (ECV), a compartment intermediate between early and late endosomes. Accordingly, lysosomal degradation of HRV2 was suppressed, whereas its conformational change and infectivity remained unaffected by this drug. Analysis of the subcellular distribution of HRV2 and fluid-phase markers in the presence of nocodazole by FFE revealed no difference from the control incubation in the absence of nocodazole. ECV and late endosomes thus have identical electrophoretic mobilities, and intraluminal pHs of <5.6 and allow uncoating of HRV2. As bafilomycin not only dissipates the low endosomal pH but also blocks transport from early to late endosomes in HeLa cells, its inhibitory effect on viral infection could in part also be attributed to trapping of virus in early endosomes which might lack components essential for uncoating. Consequently, inhibition of viral uncoating by bafilomycin cannot be taken to indicate a low pH requirement only. 相似文献
995.
Broad immunocytochemical localization of the formylpeptide receptor in human organs, tissues, and cells 总被引:3,自引:0,他引:3
E. L. Becker Faripour A. Forouhar Margaret L. Grunnet Francois Boulay Marianne Tardif Barbara-Jean Bormann Darlene Sodja Richard D. Ye Joseph R. Woska Jr Philip M. Murphy 《Cell and tissue research》1998,292(1):129-135
The formylpeptide receptor (FPR), previously found only on polymorphonuclear leukocytes and monocytes/macrophages, responds to both synthetic N-formyl oligopeptides and those produced by bacteria. The cDNA for human FPR has been cloned and a rabbit polyclonal antiserum directed against a synthetic 11-amino-acid peptide corresponding to the deduced carboxy-terminus has been produced. We have now extensively characterized and used the antibody to detect FPR on normal human tissues and cell types. The receptor antigen is present on some epithelial cells, especially those with a secretory function, and on some endocrine cells, e.g., follicular cells of the thyroid and cortical cells of the adrenal. Liver hepatocytes and Kupffer cells are positive. Smooth muscle and endothelial cells are also generally positive. In the brain and spinal cord, the neurons of the motor, sensory, and cerebellar systems, and those of the parasympathetic and sympathetic systems stain positively. These data suggest that the putative endogenous agonist for FPR or an antigenically similar receptor reacts with cellular targets in the neuromuscular, vascular, endocrine, and immune systems. 相似文献
996.
P. J. Ainsworth C. F. Bolton B. C. Murphy J. A. Stuart A. F. Hahn 《Human genetics》1998,103(2):242-244
X-linked Charcot-Marie-Tooth disease (CMTX) is a peripheral nerve disorder that has been linked to mutations in the connexin
32 gene (Cx32). These mutations have been shown to be genetically heterogeneous, though recurrences of specific mutations
in apparently unrelated families have been seen. The majority of mutations have been shown to be missense, resulting in non-conservative
amino acid changes. A few mutations resulting in a premature termination of protein translation, including both nonsense mutations
as well as frameshifting microdeletions, have been documented. We would like to report a deletion mutation that appears to
eliminate the entire coding sequence of the Cx32 gene, but which has been shown to segregate with a clinical phenotype not
unlike that seen in individuals with a less severe alteration of the Cx32 gene. The causes at a cellular level of the CMTX
phenotype are still not fully clear, though there has been speculation that these may involve a dominant negative effect where
the mutant connexin 32 suppresses the function of other connexins. Studies of kindreds such as this, where in CMTX-affected
males the Cx32 gene product is totally absent, will help us to better understand the molecular mechanisms underlying the clinical
phenotype associated with this disorder.
Received: 22 December 1997 / Accepted: 8 May 1998 相似文献
997.
998.
Rhodanese activity from crude extracts of Thiobacillus sp. strain IV-85 was demonstrated in polyacrylamide gels after incubation in the reaction mixture by staining with dichloroindophenol in the presence of methylphenazonium methosulfate. The sensitivity of the staining system was found to be 8 × 10-7 moles of sulfite. 相似文献
999.
1000.