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111.
The number of described species on the planet is about 1.9 million, with ca. 17,000 new species described annually, mostly from the tropics. However, taxonomy is usually described as a science in crisis, lacking manpower and funding, a politically acknowledged problem known as the Taxonomic Impediment. Using data from the Fauna Europaea database and the Zoological Record, we show that contrary to general belief, developed and heavily-studied parts of the world are important reservoirs of unknown species. In Europe, new species of multicellular terrestrial and freshwater animals are being discovered and named at an unprecedented rate: since the 1950s, more than 770 new species are on average described each year from Europe, which add to the 125,000 terrestrial and freshwater multicellular species already known in this region. There is no sign of having reached a plateau that would allow for the assessment of the magnitude of European biodiversity. More remarkably, over 60% of these new species are described by non-professional taxonomists. Amateurs are recognized as an essential part of the workforce in ecology and astronomy, but the magnitude of non-professional taxonomist contributions to alpha-taxonomy has not been fully realized until now. Our results stress the importance of developing a system that better supports and guides this formidable workforce, as we seek to overcome the Taxonomic Impediment and speed up the process of describing the planetary biodiversity before it is too late.  相似文献   
112.
Inner cell masses (ICM) from in vitro produced day 8 or 9 bovine blastocysts were isolated by immunosurgery and cultured under different conditions in order to establish which of two feeder cell types and culture media were most efficient in supporting attachment and outgrowth of the bovine ICM cells. The efficiency of attachment and outgrowth of the ICM cells could be markedly improved when STO feeder cells were used instead of bovine uterus epithelial cells, and by using charcoal-stripped serum instead of normal serum to supplement the culture medium. More than 20 stable cell lines were obtained. Some of these lines were examined by immunofluorescence for developmentally regulated markers. From these results we conclude that the cell lines resemble epithelial cells, rather than pluripotent ICM cells. The developmental potential of cells of one of the lines was tested in the nuclear transfer assay. The cell line could support the initial development of enucleated oocytes, but none of the reconstructed embryos passed the eight-cell block. © 1995 Wiley-Liss, Inc.  相似文献   
113.
Rheumatoid arthritis (RA) is a painful systemic disease and is believed to be exacerbated by stress. Relaxation and biofeedback strategies have demonstrated utility in alleviating both pain and stress-related symptomatology, and therefore were tested for efficacy with this disease in a two-phase study. First, 24 patients were taught a relaxation technique and then trained in either temperature elevation or reduction. Second, a group of 15 patients thus trained was compared with 8 others who received traditional physiotherapy modalities. Psychological tests, functional/physical evaluations, as well as measurements related to pain, sleep, and other activities were carried out. Results of the first study revealed significant and positive changes following treatment that were primarily related to pain, tension, and sleep patterns for both groups, but no differential effects were noted between temperature elevation or reduction conditions. This was attributed to both groups having maintained temperature above baseline during biofeedback training. The results of the second study consistently favored the relaxation and biofeedback over the physiotherapy group on the physical/functional indices. The psychological measures tended to remain constant throughout both studies, leading to the conclusion that the effectiveness of treatment was specific to physical functioning rather than to a psychological enhancement of well-being.This work was conducted in partial fulfillment of the doctoral requirements at North Texas State University by Phillip McGraw. This work was also performed pursuant to Institutional Grant No. 5-S07-RR05426-12 and NIAMDD No. 5 P60 AM20628-02.  相似文献   
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115.
The genera Cimex Linnaeus and Oeciacus Stål (Heteroptera: Cimicidae) are common haematophagous ectoparasites of bats or birds in the Holarctic region. Both their phylogenetic relationship and the systematics of the entire family previously were based on data from morphology and host relationships. Relationships among nine species of the genus Cimex and three species of the genus Oeciacus were analysed here using two mitochondrial and three nuclear genes. Cimex was shown to be paraphyletic with respect to Oeciacus. Oeciacus is thus proposed as a synonym of Cimex. The characteristic phenotype of Oeciacus results from the specific host association with different species of swallows (Hirundinidae). The morphological characters that have been used as diagnostic for the genera were shown to be valid and can be further used for determination at species level. The present analyses recovered the four traditional morphologically defined species groups of the genus Cimex. However, their relationships were poorly resolved – only the C. hemipterus group showed a well‐supported relationship to the C. pipistrelli group. The molecular differentiation within the Palaearctic C. pipistrelli and the Nearctic C. pilosellus species groups correlates with their karyotype differentiation. Furthermore, the analyses suggest poly‐ or paraphyly of the former genus Oeciacus. Either way this indicates there is a large amount of host‐associated phenotypic convergence in either bat‐ or bird‐associated groups of species. The probability of host choice and subsequent switch in Cimicidae are discussed and possible scenarios of the evolution of host association in species of Cimex are suggested.  相似文献   
116.
Abstract— Wharton et al. (1992) provided an extensive reappraisal of the phylogenetic analysis of the subfamilies of Braconidae by Quicke and van Achterberg (1990). In this critique they drew attention to a number of errors in our data matrix and made a number of useful suggestions regarding character coding and polarization. However, they also make a number of erroneous statements that, if anything, present our work in a worse light. We therefore provide here some discussion of the comments by Wharton et al. indicating where we are in agreement and where we believe our initial interpretations were correct. We also take this opportunity to correct some additional mistakes that have subsequently been unearthed in our original data matrix.  相似文献   
117.
The symbiotic association of corals and unicellular algae of the genus Symbiodinium in the southern Persian/Arabian Gulf (PAG) display an exceptional heat tolerance, enduring summer peak temperatures of up to 36 °C. As yet, it is not clear whether this resilience is related to the presence of specific symbiont types that are exclusively found in this region. Therefore, we used molecular markers to identify the symbiotic algae of three Porites species along >1000 km of coastline in the PAG and the Gulf of Oman and found that a recently described species, Symbiodinium thermophilum, is integral to coral survival in the southern PAG, the world''s hottest sea. Despite the geographic isolation of the PAG, we discovered that representatives of the S. thermophilum group can also be found in the adjacent Gulf of Oman providing a potential source of thermotolerant symbionts that might facilitate the adaptation of Indian Ocean populations to the higher water temperatures expected for the future. However, corals from the PAG associated with S. thermophilum show strong local adaptation not only to high temperatures but also to the exceptionally high salinity of their habitat. We show that their superior heat tolerance can be lost when these corals are exposed to reduced salinity levels common for oceanic environments elsewhere. Consequently, the salinity prevailing in most reefs outside the PAG might represent a distribution barrier for extreme temperature-tolerant coral/Symbiodinium associations from the PAG.  相似文献   
118.
A 25-year-old paraplegic woman was able to gain control of her debilitating leg and bladder spasms and abdominal pain using self-directed EMG biofeedback. The case is significant in that she previously had only cursory exposure to biofeedback as an undergraduate student and received only minimal support and direction from an instructor. She proceeded through daily home practice using a borrowed EMG unit and audiotapes from Lester Fehmi's Open Focus series. Records were kept of the frequency and intensity of her pain and spasms, as well as the frequency and procedures of her home practice. She also maintained a record of specific psychosocial events in her life, which, over time, showed a strong, consistent pattern of influence on the recurrence and severity of her symptoms. The woman's physician declared her medical progress remarkable and encouraged her biofeedback work. At 2-year follow-up, she remains virtually symptom- and medication-free. Her successful biofeedback training program provides support for the value of client-directed biofeedback in selected cases.  相似文献   
119.
A 25-year-old paraplegic woman was able to gain control of her debilitating leg and bladder spasms and abdominal pain using self-directed EMG biofeedback. The case is significant in that she previously had only cursory exposure to biofeedback as an undergraduate student and received only minimal support and direction from an instructor. She proceeded through daily home practice using a borrowed EMG unit and audiotapes from Lester Fehmi'sOpen Focus series. Records were kept of the frequency and intensity of her pain and spasms, as well as the frequency and procedures of her home practice. She also maintained a record of specific psychosocial events in her life, which, over time, showed a strong, consistent pattern of influence on the recurrence and severity of her symptoms. The woman's physician declared her medical progress remarkable and encouraged her biofeedback work. At 2-year follow-up, she remains virtually symptom- and medication-free. Her successful biofeedback training program provides support for the value of client-directed biofeedback in selected cases.  相似文献   
120.
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