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101.
  1. Birds colliding with turbine rotor blades is a well‐known negative consequence of wind‐power plants. However, there has been far less attention to the risk of birds colliding with the turbine towers, and how to mitigate this risk.
  2. Based on data from the Smøla wind‐power plant in Central Norway, it seems highly likely that willow ptarmigan (the only gallinaceous species found on the island) is prone to collide with turbine towers. By employing a BACI‐approach, we tested if painting the lower parts of turbine towers black would reduce the collision risk.
  3. Overall, there was a 48% reduction in the number of recorded ptarmigan carcasses per search at painted turbines relative to neighboring control (unpainted) ones, with significant variation both within and between years.
  4. Using contrast painting to the turbine towers resulted in significantly reduced number of ptarmigan carcasses found, emphasizing the effectiveness of such a relatively simple mitigation measure.
  相似文献   
102.
Chlamydia trachomatis is a common sexually transmitted infection that is associated with a range of serious reproductive tract sequelae including in women Pelvic Inflammatory Disease (PID), tubal factor infertility, and ectopic pregnancy. Ascension of the pathogen beyond the cervix and into the upper reproductive tract is thought to be necessary for these pathologies. However, Chlamydia trachomatis does not encode a mechanism for movement on its genome, and so the processes that facilitate ascension have not been elucidated. Here, we evaluate the factors that may influence chlamydial ascension in women. We constructed a mathematical model based on a set of stochastic dynamics to elucidate the moderating factors that might influence ascension of infections in the first month of an infection. In the simulations conducted from the stochastic model, 36% of infections ascended, but only 9% had more than 1000 bacteria ascend. The results of the simulations indicated that infectious load and the peristaltic contractions moderate ascension and are inter-related in impact. Smaller initial loads were much more likely to ascend. Ascension was found to be dependent on the neutrophil response. Overall, our results indicate that infectious load, menstrual cycle timing, and the neutrophil response are critical factors in chlamydial ascension in women.  相似文献   
103.
At the biomedical, regulatory, and public level, considerable concern surrounds the concept that inappropriate exposure to endocrine-disrupting chemicals, especially during the prenatal and/or neonatal period, may disrupt normal reproductive tract development and adult function. The intent of this review was to 1. Describe some unique advantages of the hamster for perinatal endocrine disruptor (ED) studies, 2. Summarize the morphological and molecular consequences of exposure to the established perinatal ED, diethylstilbestrol, in the female and male hamster, 3. Present some new, histomorphological insight into the process of neonatal diethylstilbestrol-induced disruption in the hamster uterus, and 4. Introduce recent efforts and future plans to evaluate the potency and mechanism of action of other putative EDs in the hamster experimental system. Taken together, the findings indicate that the hamster represents a unique and sensitive in vivo system to probe the phenomenon of endocrine disruption. The spectrum of candidate endpoints includes developmental toxicity, neoplasia, and more subtle endpoints of reproductive dysfunction.  相似文献   
104.
Polarity-defective mutants of Aspergillus nidulans   总被引:4,自引:0,他引:4  
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105.
Rimmed vacuoles in myofibers are thought to be due to the accumulation of autophagic vacuoles, and can be characteristic in certain myopathies with protein inclusions in myofibers. In this study, we performed a detailed clinical, molecular, and pathological characterization of Becker muscular dystrophy patients who have rimmed vacuoles in muscles. Among 65 Becker muscular dystrophy patients, we identified 12 patients who have rimmed vacuoles and 11 patients who have deletions in exons 45–48 in DMD gene. All patients having rimmed vacuoles showed milder clinical features compared to those without rimmed vacuoles. Interestingly, the rimmed vacuoles in Becker muscular dystrophy muscles seem to represent autophagic vacuoles and are also associated with polyubiquitinated protein aggregates. These findings support the notion that rimmed vacuoles can appear in Becker muscular dystrophy, and may be related to the chronic changes in muscle pathology induced by certain mutations in the DMD gene.  相似文献   
106.
Maltosylisothiocyanate (MITC), synthesized as an affinity label for the hexose carrier, has been reported to label a Band 3 or Mr = 100,000 protein in human erythrocytes, in contradistinction to many studies showing the carrier as a Band 4.5 or Mr = 45,000-66,000 protein on gel electrophoresis. In this work the possibility that MITC interacts with the Band 3 anion transporter was studied. In intact human erythrocytes, MITC labeling was largely confined to Band 3 and was decreased by several competitive inhibitors of hexose transport. However, MITC also appeared to react with the anion transport protein, since MITC labeling of Band 3 was irreversibly decreased by the anion transport inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonate (DIDS) and since MITC also irreversibly inhibited both tritiated dihydro-DIDS labeling of Band 3 and sulfate uptake in intact cells. Although 20 microM DIDS had little effect on hexose transport, the labeling of erythrocyte Band 3 by the dihydro analog was significantly diminished by competitive inhibitors of hexose transport. These data suggest that MITC labels in part the anion transporter as well as other DIDS-reactive sites on Band 3 which appear to be sensitive to competitive inhibitors of hexose transport.  相似文献   
107.
108.
Many amyloid inhibitors resemble molecules that form chemical aggregates, which are known to inhibit many proteins. Eight known chemical aggregators inhibited amyloid formation of the yeast and mouse prion proteins Sup35 and recMoPrP in a manner characteristic of colloidal inhibition. Similarly, three known anti-amyloid molecules inhibited beta-lactamase in a detergent-dependent manner, which suggests that they too form colloidal aggregates. The colloids localized to preformed fibers and prevented new fiber formation in electron micrographs. They also blocked infection of yeast cells with Sup35 prions, which suggests that colloidal inhibition may be relevant in more biological milieus.  相似文献   
109.
E May  J M Jeltsch    F Gannon 《Nucleic acids research》1981,9(16):4111-4128
It has been reported that SV40-transformed V 11 F 1 clone 1 subclone 7 rat cells (subclone 7) produce a super T antigen of 115,000 M. This super T antigen is entirely SV40 coded and is synthesized by translation of an elongated form of SV40 early mRNA (May, E., Kress, M. Daya-Grosjean, L., Monier, R. and May, P. (1981) J. Virol., 37, 24-35). The results reported here show that there is only one independent insertion of viral DNA in the cellular genome of subclone 7 cells. When DNA from subclone 7 cells was cleaved with Bam HI endonuclease two distinct SV40 sequence containing fragments were generated with sizes of 5 Kb and 10 Kb, respectively. Two recombinant cosmids were constructed by insertion of the 5 Kb and 10 Kb fragments, respectively, into cosmid pHC 79. Using restriction map analysis and nucleotide sequencing, we showed that the 5 Kb fragment actually contained the complete sequence of a gene encoding super T antigen. As compared to the normal SV40 early gene, the sequence of super T gene showed the following rearrangements: (i) The segment between nucleotides 4116 - 3544 was duplicated in a direct order and (ii) these two copies of 573 nucleotide sequence were separated by a 93 nucleotide tract which was a nearly perfect inverted repeat of the segment located between nucleotides 4868 and 4776 (nucleotide numbering used here = Weissmann number +17).  相似文献   
110.
AlphaB-Crystallin has for a long time been considered a specific eye lens protein. Later on it appeared that this protein belongs to the family of the small heat shock proteins and that it occurs also extra-lenticularly in many different cell types. AlphaB-Crystallin is mainly present in the cytoplasm, but there are some indications that it might have a function in the nucleus too. However, till now its presence in the nucleus is uncertain. We therefore compared the localization of alphaB-crystallin in nine cell lines cultured under normal conditions using four different antisera. All four antisera gave a diffuse staining for alphaB-crystallin in the cytoplasm, but one of the antibodies consistently showed nuclear staining in eight of the cell types, in the form of distinct speckles. These speckles are equally pronounced in the different cell types, whether or not cytoplasmic alphaB-crystallin is present. Preabsorption of the antiserum with alphaB-crystallin abolished the staining. Furthermore we demonstrate that if only minor amounts of alphaB-crystallin are present, the protein seems to be located exclusively in the nucleus. However, in case of higher amounts of protein, alphaB-crystallin is distributed between cytoplasm and nucleus. The nuclear alphaB-crystallin exists, like the cytoplasmic alphaB-crystallin, in non-phosphorylated and phosphorylated forms, is Triton-insoluble but can be extracted by 2 M NaCl. These data suggest that alphaB-crystallin might be bound to the nuclear matrix per se or to nuclear matrix proteins via other proteins. In agreement with other nuclear matrix proteins, nuclear alphaB-crystallin staining turns diffuse upon mitosis and leaves the chromosomes unstained. Double staining experiments revealed colocalization of alphaB-crystallin with the splicing factor SC35 in nuclear speckles, suggesting a role for alphaB-crystallin in splicing or protection of the splicing machinery.  相似文献   
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