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171.
Sabine Buurgaard Sørensen Bjarne Larsen Jihad Orabi Marian Ørgaard 《Nordic Journal of Botany》2014,32(4):503-510
During the past centuries Danish populations of Primula farinosa have seriously declined in number. We investigated the genetic structure and genetic diversity of plants of seven populations from two different regions, Zealand and Bornholm in Denmark, using three AFLP markers. Two populations from nearby Scania, Sweden were included as reference. We found 54 unambiguously polymorphic loci. The genetic structure analysis suggested division of the 268 plants into three distinct groups, to a large extent matching the geographical distribution of the populations. Analysis of molecular variance (AMOVA) indicated significant genetic differentiation of 67% within populations and 33% among the populations. Our results suggest that genetic differentiation among regions and unique local genetic diversity should carefully be considered in future conservation attempts if we are to maintain as much genetic variation as possible. We present a historical overview of the decline in Danish populations and discuss conservation management and restoration strategies. 相似文献
172.
Chen Ying Klingen Tor A Wik Elisabeth Aas Hans Vigeland Einar Liestøl Knut Garred Øystein Mæhlen Jan Akslen Lars A Lømo Jon 《Diagnostic pathology》2014,9(1):1-2
Squamous cell carcinomas (SCCs) are uncommon, high-grade tumors, predominantly composed of round cells in the prepuce. The aim of this study is to better define the clinicopathologic features of this neoplasm. We conducted cyto-histopathologic analysis on the manifestations of the prepuce SCC by H &; E staining in a terrier mix dog. Grossly, tumor was large, multiple erythematous patch, and ulcerated masses frequently affecting the prepuce and deeply invading to distal prepuce out from the ventro-lateral of penis and the tumor covered by a necrotic discharge. Cytological evaluation of fine-needle aspirates from the cutaneous mass from the prepuce comprised of round nuclei, coarse chromatin pattern, distinct nucleoli and nuclear pleomorphism. Furthermore, the neoplastic cells were pleomorphic, round to caudate in shape, exhibiting prominent anisokaryosis and anisocytosis with rare mitotic features. Microscopically, the lesions were predominantly composed of atypical round cells disposed in interlacing fascicles. Frequent findings include keratin formation, horn pearls, mitoses and cellular atypia. The cells showed distinct borders, ranged from polygonal to round or elongate and had moderate amounts of eosinophilic cytoplasm. The histopathologic features coupled with the cytopathology findings led to a diagnosis of squamous cell carcinoma. To the authors’ knowledge, this is the first time that multiple erythematous plaques have undergone malignant transformation in a terrier mix dog. The virtual slide(s) for this article can be found here:
http://www.diagnosticpathology.diagnomx.eu/vs/5748771971272873 相似文献
173.
Yang Ning Huang Bin Tsinkalovsky Oleg Brekkå Narve Zhu Huaiyang Leiss Lina Enger Per Øyvind Li Xingang Wang Jian 《Cancer cell international》2014,14(1):1-7
The anticancer effects of ceramide have been reported in many types of cancers but less in lung cancer. In this study, we used C2-ceramide to further investigate its possible anticancer effects and mechanisms on non-small cell lung cancer (NSCLC) H1299 cells. The result of cell proliferation in terms of trypan blue assay showed high dose of C2-ceramide inhibited cell survival after 24 h treatment. The flow cytometry-based assays indicated the effect of apoptosis, chromatin condensation, and G1 arrest in terms of Annexin V/propidium iodide (PI), DAPI, and PI stainings, respectively. Moreover, the decreased protein level of p-Akt, p-NFκB, survivin and cyclin A2 were detected by Western blot assay. Taken together, these results indicated the antiproliferative effect of C2-ceramide is majorly responsible for cell apoptosis in lung cancer H1299 cells. 相似文献
174.
Ingibjörg E. Einarsdóttir Kjell J. Nilssen Svein O. Øren Martin Iversen 《Polar Biology》2000,23(4):231-235
In order to elucidate the immune responses of Arctic charr in relation to temperature, groups were acclimated to a moderate
(9°C) and a cold temperature regime (4°C), as well as subjected to a temperature decrease (from 9 to 4°C) immediately prior
to an immunization with sheep red blood cells. The charr kept at 9°C responded with increased primary and secondary antibody
titres, as seen by direct haemagglutination, while fish at 4°C, as well as the fish subjected to a temperature reduction,
displayed lower and lowest antibody titres, respectively, and only after a second immunization. It is concluded that Arctic
charr can respond to a cellular antigen with a humoral immune response typical for other teleosts, but that the immune response
is delayed and diminished at low temperatures. This temperature-induced immune suppression is intensified if the fish have
not been acclimated to cold water prior to immunization.
Accepted: 10 October 1999 相似文献
175.
176.
Summary Hyperosmolality adversely affects growth of murine hybridoma cells. Addition of low concentrations of betaine to the growth medium will protect the hyperosmotically stressed cells. The protective effect is observed as increased growth rate and cell density of the stressed cell cultures. The cellular production of monoclonal antibody is related to growth rate in an inverse fashion. 相似文献
177.
Ronette L. Kolotkin Christie Zunker Truls Østbye 《Obesity (Silver Spring, Md.)》2012,20(12):2325-2333
We review the literature on the relationship between obesity and sexual functioning. Eleven population‐based studies, 20 cross‐sectional non‐population‐based studies, and 16 weight loss studies are reviewed. The consistency of findings suggests that the relationship between obesity and reduced sexual functioning is robust, despite diverse methods, instruments, and settings. In most population‐based studies, erectile dysfunction (ED) is more common among obese men than among men of recommended weight. Studies of patients in clinical settings often include individuals with higher degrees of obesity, with most studies showing a relationship between obesity and lower levels of sexual functioning, especially ED. The few studies that include both genders generally report more problems among women. Most studies of patients with comorbidities associated with obesity also find an association between obesity and reduced sexual functioning. Most weight loss studies demonstrate improvement in sexual functioning concurrent with weight reduction despite varying study designs, weight loss methods, and follow‐up periods. We recommend that future studies (i) investigate differences and similarities between men and women with respect to obesity and sexual functioning, (ii) use instruments that go beyond the assessment of sexual dysfunction to include additional concepts such as sexual satisfaction, interest, and arousal and, (iii) assess how and the degree to which obese individuals are affected by sexual difficulties. Given the high prevalence of obesity and the inverse association between body mass and sexual functioning, we also recommend that sexual functioning should be more fully addressed by clinicians, both in general practice and in weight loss programs. 相似文献
178.
A. P. MØLLER 《Journal of evolutionary biology》2010,23(8):1689-1698
Animals fleeing a potential predator can escape horizontally or vertically, although vertical flight is more expensive than horizontal flight. The ability to escape in three dimensions by flying animals has been hypothesized to result in greater survival and eventually slower senescence than in animals only fleeing in two dimensions. In a comparative study of flight initiation distance in 69 species of birds when approached by a human, I found that the amount of variance explained by flight initiation distance was more than four times as large for the horizontal than the vertical component of perch height when taking flight. The slope of the relationship between horizontal distance and flight initiation distance (horizontal slope) increased with increasing body mass across species, whereas the slope of the relationship between vertical distance and flight initiation distance (vertical slope) decreased with increasing body mass. Therefore, there was a negative relationship between horizontal and vertical slope, although this negative relationship was significantly less steep than expected for a perfect trade‐off. The horizontal slope decreased with increasing density of the habitat from grassland over shrub to forest, whereas that was not the case for the vertical slope. Adult survival rate increased and rate of senescence (longevity adjusted for survival rate, body mass and sampling effort) decreased with increasing vertical, but not with horizontal slope, consistent with the prediction that vertical escape indeed provides a means of reducing the impact of predation. 相似文献
179.
Settlement of cultured Balanus amphitrite cyprid larvae was tested on different non-solid hydrogel surfaces. Gels consisting of alginate (highly anionic), chitosan (highly cationic), polyvinyl alcohol substituted with light-sensitive stilbazolium groups (PVA-SbQ; very low cationic) and agarose (neutral) were applied in cell culture multi-well plates. Polystyrene served as a solid surface reference. Preliminary experiments were performed to determine whether any substances leaching out of the gels could inhibit barnacle settlement. Whilst leachate from the gels revealed no toxicity towards Artemia salina nauplius larvae, PVA-SbQ in solution at and above a concentration of 0.4 ppm inhibited B. amphitrite cyprid settlement. Gels were therefore washed to avoid such effects during further testing, and toxicity and settlement tests with B. amphitrite nauplii and cyprids, respectively, applied to verify that washing was effective. Settlement was tested directly on the different test materials, followed by a quality test of non-settled larvae. All gels inhibited barnacle settlement compared to the polystyrene controls. Gels consisting of 2.5% PVA-SbQ or 0.5% agarose showed promising antifouling properties. Although some settlement occurred on 2.5% PVA-SbQ gels, metamorphosis was clearly inhibited. Only 10% of the larvae had settled on 0.5% agarose gels after 8 d. Less than 40% settlement occurred on alginate gels, as well as on 2% chitosan gels. Quality testing showed that the majority of remaining non-settled larvae in all gel experiments were able to settle when offered a suitable solid substratum. 相似文献
180.
Frede Østergaard Andersen Per Famme 《Journal of experimental marine biology and ecology》1983,66(1):89-92
A precise and rapid method is described for the determination of fresh weight of aquatic plants and animals. The determination of fresh weight is done gravimetrically with a spectrophotometric estimate of adherent water providing a correction for adherent water. 相似文献