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1.
Three bovid species are present at Dorn-Dürkheim 1. The overwhelmingly abundant species is a boselaphine, Miotragocerus sp., with smaller and less advanced teeth than Tragoportax amalthea from Pikermi, Greece. Miotragocerus was present in the latest middle Miocene and Vallesian of western and central Europe and survived into the Turolian. The other two bovid species remain enigmatic and of uncertain tribal affiliation. Each is represented by very few teeth, none of them associated. One species is larger and the other smaller than the Miotragocerus sp. Mesowear analysis of M2s and M3s was used to investigate the dietary regime of Miotragocerus sp. from Dorn-Dürkheim 1. Miotragocerus was found to be linked to extant browsing ungulates close to the transition to mixed feeders. The percentage of abrasive food components like grass in the diet of this species was probably close to 10%. This ratio suggests Miotragocerus is intermediate between the two hipparionine horse species of this early Turolian (MN11) palaeoenvironment.  相似文献   
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With the increased popularity of suction lipoplasty procedures, attention has been focused on their safety. One significant concern involves the rotary vane aspirators used to provide the suction required for the procedure. A series of experiments was carried out to determine whether aerosols are produced during the use of a rotary vane aspirator, since aerosols are known to be hazardous under appropriate conditions. Using a viable strain of Pseudomonas aeruginosa, we challenged the system through the suction port, and the exhaust from the aspirator was then cultured in a particle sampler. Results indicate that viable pathogens are released from the exhaust in physiologically significant particles capable of penetrating to the level of the alveolus in the normal human lung. These infectious particles were produced for 3 hours after the initial challenge. When an appropriate filtration device was attached to the aspirator outflow, the aspirator pump and environment were protected. In the absence of an appropriate filtration device, the aerosolized particles may constitute a hazard to patients or medical workers in the vicinity of the aspirator.  相似文献   
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Postoperative nausea and vomiting frequently complicate outpatient anesthesia and surgery. The duration of treatment for this complication must occasionally extend beyond discharge from the hospital. In this study, we evaluated the commonly used anti-emetic promethazine for its efficacy in the post-discharge period. Adult outpatient surgical patients who had excessive postoperative nausea and vomiting in the recovery room, or who were at risk for postoperative nausea and vomiting following discharge were given two promethazine suppositories (25 mg) for home use. All patients were contacted by our recovery room nurses on the first business day after their surgery and questioned as to their use of the suppositories and, if used, their efficacy. We found that 55 percent of patients given promethazine suppositories for home use had nausea and vomiting in the post-discharge period. Of the patients given promethazine, 89 percent used the suppositories. All of these patients reported improvement in their symptoms following use of the suppositories. None reported adverse effects from the promethazine suppositories. In conclusion, we found promethazine suppositories to be an inexpensive and efficacious treatment for nausea and vomiting in adult outpatient surgical patients following discharge from the hospital. Side-effects were minimal, and our patients voiced no complaints about this mode of therapy. We recommend this therapy for treatment of nausea and vomiting after hospital discharge following adult outpatient surgery.  相似文献   
4.
The Coomassie brilliant blue assay for the determination of protein has been extended to rapidly and conveniently measure the protein concentration of cells growing in culture in a 96-well microtiter format. Modifications of the standard assay include sodium hydroxide to solubilize the cells and ovalbumin, instead of bovine serum albumin, as a protein standard. The procedure allows a large number of small samples to be assayed simultaneously. Two examples of its use, enzyme-specific activity and drug resistance, are shown. An assay for acetylcholinesterase activity in the same culture plate is demonstrated. G418, an inhibitor of cell protein synthesis, is frequently used to select for cells transfected with the neomycin resistance gene. The required concentration of G418 can be easily determined with this protein assay.  相似文献   
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Triple negative breast cancer (TNBC) represents an anomalous subset of breast cancer with a greatly reduced (30%) 5-year survival rate. The enhanced mortality and morbidity of TNBC arises from the high metastatic rate, which requires the acquisition of AnR, a process whereby anchorage-dependent cells become resistant to cell death induced by detachment. In this study TNBC cell lines were selected for AnR, and these cell lines demonstrated dramatic enhancement in the formation of lung metastases as compared with parental cells. Genetic analysis of the AnR subclones versus parental cells via next generation sequencing and analysis of global alternative RNA splicing identified that the mRNA splicing of cytoplasmic polyadenylation element binding 2 (CPEB2), a translational regulator, was altered in AnR TNBC cells. Specifically, increased inclusion of exon 4 into the mature mRNA to produce the CPEB2B isoform was observed in AnR cell lines. Molecular manipulations of CPEB2 splice variants demonstrated a key role for this RNA splicing event in the resistance of cells to anoikis. Specifically, down-regulation of the CPEB2B isoform using siRNA re-sensitized the AnR cell lines to detachment-induced cell death. The ectopic expression of CPEB2B in parental TNBC cell lines induced AnR and dramatically increased metastatic potential. Importantly, alterations in the alternative splicing of CPEB2 were also observed in human TNBC and additional subtypes of human breast cancer tumors linked to a high metastatic rate. Our findings demonstrate that the regulation of CPEB2 mRNA splicing is a key mechanism in AnR and a driving force in TNBC metastasis.  相似文献   
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A method is presented using [14C]5′-AMP as a substrate for measuring 5′-nucleotidase activity in the presence of interfering phosphatases. An inhibitor of 5′-nucleotidase, α,β-methyleneadenosine diphosphate is utilized, and the enzyme activity is measured as the difference between total phosphatase activity and inhibitor-insensitive activity.  相似文献   
9.
A radioligand-binding assay employing adenine analog-binding protein from rabbit crythrocytes and [3H]adenosine of high specific activity measures less than 1 pmol of adenosine in neutral HClO4 extracts of tissue. Adenine and its nucleotides interfere with adenosine binding, so are removed by preliminary chromatography on PEI and phenyldihydroboryl cellulose columns. Free and bound adenosine are separated by filtration through cellulose acetate membranes or by absorbing free adenosine on charcoal. The recovery of 1.0–4.0 pmol of adenosine added to blood extracts and carried through purification and radioligand assay averaged 100% with an absolute error of ±0.23 pmol.  相似文献   
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