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351.
Joanna Mascot 《绿色中国(A版)》2004,(17):72-75
生活在声色犬马、信息狂暴的时代,总觉得自己好像在不自觉地跟着一些风儿瞎跑,但是每每静下心来,总会发觉自己原来是莫名的肤浅。面对着时下那些形形色色的休闲方式,虽谓之时尚,但让人总感觉是在用身体上片刻的修整甚或疲惫来换取劳累不堪的心情一阵解脱,然而须臾之后,心灵却仍 相似文献
352.
Drill wounds in balsam fir and hemlock roots activated the nonspecific resistance mechanisms of compartmentalization in wood and necrophylactic periderm in bark. Tangential bands of resin ducts localized around the wounds constituted the barrier zones in the secondary xylem of conifer roots. Barrier zones were more extensive in roots which showed symptoms characteristic of invasion by fungi and bacteria after wounding. This observation supports an expanded definition of barrier zones; barrier zones may form not only in response to mechanical wounds but also in response to xylem injury caused by pathogens. Multiple bands of resin ducts were common in young xylem when bark lesions developed around wounds. Necrophylactic periderms isolared dead bark from living bark. Development of phellem cells with dark contents and thick suberized walls, typical of exophylactic periderm, followed initiation of necrophylactic periderm. The wound responses were similar in both balsam fir and hemlock. 相似文献
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Rowan Trebilco Benjamin S. Halpern Joanna Mills Flemming Chris Field Wade Blanchard Boris Worm 《Biological conservation》2011,(5):1758-1766
Given the widely recognized need to better protect the oceans but limited resources to do so, methods for prioritizing potential protected area sites are important. This is particularly true for the open oceans, where few protected areas currently exist and data availability is limited. Here, we examine the relationship between the distributions of tuna and billfish species richness (an indicator of pelagic biodiversity), the human impact drivers of fishing pressure (quantified as cumulative removals) and sea surface temperature increase (quantified as the increase in large positive anomalies) in tropical to temperate oceans at the scale of a 5° × 5° grid. We investigate relationships using Generalised Additive Models and Regression Tree analysis, and identify the top 50 “hotspot” cells for species richness and each of the two impact drivers. We find that both impact drivers significantly overlap with high species richness, but relationships are complex, non-linear and ocean-basin specific. Higher fishing pressure is associated with higher species richness in the Indian and Pacific Oceans, and this overlap is particularly prominent in the central Pacific, and in the Indian Ocean around Sri Lanka. In the Pacific and Atlantic Oceans, species richness is generally higher in areas that have seen lower levels of change in sea surface temperature and only one cell, near Easter Island, is a hotspot for species richness and sea surface temperature increase. While species richness and impact drivers overlap in some areas, there are many areas with high species richness and limited apparent impact. This suggests that area-based conservation strategies that aim to protect areas of high pelagic biodiversity may be achievable with limited displacement of fishing effort. 相似文献
355.
Gerou-Ferriani M McBrearty AR Burchmore RJ Jayawardena KG Eckersall PD Morris JS 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2011,40(2):159-173
Background: Serum electrophoretic profiles in cats are poorly characterized with respect to the proteins that comprise the globulin fractions, and interpretation of the electrophoretograms is routinely done in the absence of information about identity of the proteins found within each fraction. Objectives: The aims of this study were to compare protein fractions separated by serum protein electrophoresis (SPE) in healthy cats and in cats with lymphoma and to confirm some component proteins in the major fractions following SPE using tandem mass fingerprinting analysis (TMFA). Methods: Total protein concentration was measured and agarose gel SPE performed on serum from 14 healthy cats and 14 cats with lymphoma. The absolute protein concentration within each fraction was compared between the 2 groups. Bands corresponding to the SPE fractions were excised from the gels of 2 control cats and 1 cat with lymphoma and analyzed by liquid chromatography coupled to mass spectrometry. Results were compared with sequences in the National Center for Biotechnology Information protein database. Results: Median albumin concentrations were significantly decreased and median β‐globulin concentrations were significantly increased in cats with lymphoma. Narrow electrophoretic spikes were present in the β/γ‐globulin fraction in 3 cats with lymphoma. Following TMFA, multiple proteins were identified in each fraction, and their mobility agreed with results from previous studies generated using alternative techniques. Inter‐α (globulin) inhibitor 4 was identified in feline serum for the first time. Conclusions: Cats with lymphoma had lower albumin and higher β‐globulin concentrations than did healthy cats. Despite limitations of one‐dimensional agarose gel SPE, TMFA provided preliminary data to confirm the protein components of the various fractions. 相似文献
356.
The cellular localization of nerve growth factor (NGF) and its receptors (TrkA, p75) was investigated during the estrous cycle in gilts. Also, the levels of expression of these factors in walls of tertiary follicles and corpora lutea (CLs) were determined using Western blot. The ovaries from days 3, 7, 16 and 20 of the cycle revealed the presence of NGF and its receptors in oocytes of secondary and tertiary follicles, follicular cells of primary and secondary follicles, thecal and granulosa cells of tertiary follicles and steroidogenic cells of CLs. In wall cells of primary follicles, NGF, TrkA and p75 staining was strongest on day 16, while in secondary follicles, only p75 was more intensely stained on day 16 and 20. In walls of small (to 3 mm in diameter) and medium (4-6 mm in diameter) follicles, NGF staining was lower on day 16, and the p75 reaction was strongest on day 20. On day 20, NGF staining in large follicles (7-10 mm in diameter) was higher than in smaller follicles. The levels of NGF and p75 in small and medium follicles were highest on day 20. The contents of NGF and TrkA in large follicles on day 20 were higher than in smaller follicles. NGF and TrkA contents in CLs were highest on day 7. Our study demonstrates that NGF, TrkA and p75 are expressed in the ovary during the estrous cycle in gilts. These results suggest that NGF and its receptors may be important for ovarian function in cycling gilts. 相似文献
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Ingrid van Hoek Hannah Hodgkiss-Geere Elizabeth F. Bode Julie Hamilton-Elliott Paul Mõtsküla Valentina Palermo Yolanda Martinez Pereira Geoff J. Culshaw Jeremy Laxalde Joanna Dukes-McEwan 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(6):2197-2210
360.
Joanna Tunikowska Przemysław Prządka Zdzisław Kiełbowicz 《Reproduction in domestic animals》2020,55(Z2):32-37
Light-based technologies are applied in various fields of medicine: for example optical diagnostics, light-activated therapy and surgery. Although light-based surgical procedures had hardly been a novelty, the revolutionizing moment for surgery came with the first use of light to cut tissue. Nowadays, surgical lasers are routinely used across numerous medical specialties, including gynaecology and urology. They are a part of the surgical treatment of benign prostatic hyperplasia, prostate carcinoma, penis carcinoma, genital skin lesions and orchidectomy. While in human urology lasers continue to establish their position as one of the standard surgical tools, veterinary patients are rarely treated with what here is still considered a technical innovation. However, through research on laser treatment of the prostate hyperplasia conducted on a canine model, veterinary medicine has gained a massive portion of data. It may prove beneficial for our clinical patients. In this review, we introduce the very principles of laser surgery as well as its current and future applications in oncologic surgery of the canine prostate gland and the male reproductive system. 相似文献