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21.
A 25-year-old Uzbek male presented with right upper abdominal pain for 20 days. On radiologic studies, a huge cystic mass was noticed in the right liver which was suspected as parasitic. The patient received right hepatic segmentectomy (segment 7), and the surgically resected mass was confirmed as cystic echinococcosis (CE), measuring 10.5 cm in its diameter. The inner surface of the cyst was bile-stained. The patient was discharged on the 8th hospital day, and was rechecked 6 months after the surgical intervention without any evidence of recurrence. The present report describes findings of an imported case of CE which represented ultrasound images of the ''ball of wool''.  相似文献   
22.
The effect of sucrose on fruiting, seed production, and seed germination of lesser centaury [Centaurium pulchellum (Sw.) Druce] was examined using explants of flowers and flower buds. Sucrose concentrations in the culture medium ranged from 0.003 to 0.3 M. It has been shown that the number of auxiliary buds, capsules dimension, number of viable seeds per capsule and seed dimensions increased with the increase of sucrose concentrations. The highest values were recorded at sucrose concentrations higher than 0.03 M, except for seeds size, which were larger at sucrose concentration ranging from 0.003 to 0.1 M. The germination of in vitro produced seeds was affected by previous culture history: a higher germination percentage was obtained in seeds that were raised from explants originally grown on medium with sucrose concentrations higher than 0.003 M.  相似文献   
23.
Ohne ZusammenfassungDie vorliegenden Versuehe wurden während meines kurzen Aufenthalts im Pflanzenphysiologisehen Institut der Universität Wien ausgeführt. Herrn Prof. Dr. Karl Höfler und Herrn Dr. H. Kinzel danke ich sehönstens auch an dieser Stelle für die Untersfützung während der Arbeit.  相似文献   
24.
We consider adaptive robust methods for lung cancer that are also dose-reactive, wherein the treatment is modified after each treatment session to account for the dose delivered in prior treatment sessions. Such methods are of interest because they potentially allow for errors in the delivered dose to be corrected as the treatment progresses, thereby ensuring that the tumor receives a sufficient dose at the end of the treatment. We show through a computational study with real lung cancer patient data that while dose reaction is beneficial with respect to the final dose distribution, it may lead to exaggerated daily underdose and overdose relative to non-reactive methods that grows as the treatment progresses. However, by combining dose reaction with a mechanism for updating an estimate of the uncertainty, the magnitude of this growth can be mitigated substantially. The key finding of this paper is that reacting to dose errors – an adaptation strategy that is both simple and intuitively appealing – may backfire and lead to treatments that are clinically unacceptable.  相似文献   
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Transgenesis enables the elucidation of gene function; however, constant transgene expression is not always desired. The tetracycline responsive system was devised to turn on and off transgene expression at will. It has two components: a doxycycline (dox)-controlled transactivator (TA) and an inducible expression cassette. Integration of these transgenes requires two transfection steps usually accomplished by sequential random integration. Unfortunately, random integration can be problematic due to chromatin position effects, integration of variable transgene units, and mutation at the integration site. Therefore, targeted transgenesis and knockin were developed to target the TA and the inducible expression cassette to a specific location, but these approaches can be costly in time, labor, and money. Here, we describe a one-step Cre-mediated knockin system in mouse embryonic stem cells that positions the TA and inducible expression cassette to a single location. Using this system, we show dox-dependent regulation of eGFP at the DNA topoisomerase 3β promoter. Because Cre-mediated recombination is used in lieu of gene targeting, this system is fast and efficient.  相似文献   
27.
The ladybird Harmonia axyridis (Pallas) is considered one of the most serious invasive species around the globe. It has spread all over North America and Western Europe, while data from southeastern Europe, especially in the Mediterranean region, are scarce. In this study we present the first confirmed data of the spread of H. axyridis throughout Croatia. Specimens were sampled and identified during the period 2008–2010. The species was recorded at 18 localities in all three colour forms in various habitat types. Light trapping was found to be a satisfactory method for collecting H. axyridis. Since there is no evidence to suggest the deliberate introduction of H. axyridis in Croatia, it can be assumed that it has spread southwards from Central and Eastern Europe, and that it will probably continue to spread. Further investigations should focus on monitoring and detailed mapping of H. axyridis in Croatia and neighbouring countries, especially in the Mediterranean region, to determine whether stable populations are present.  相似文献   
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In this study, using the quadratic saturation 310 D-optimal design method, we examined the effect of kinetin (KT), gibberellic acid (GA), and naphthalene acetic acid (NAA) on microrhizome production in ginger. The effect of GA on rhizome induction was larger than that of KT or NAA. Using simulation and optimality selection for tissue culture, we found that concentrations of GA, KT, and NAA of 1.33–2.35, 0.49–0.66, and 0.62 g/l, respectively, gave a microrhizome weight of over 0.25 g. The optimal conditions for microrhizome production were 80 g/l sucrose, 2 × MS macro-elements, and 1 × MS micro-elements, with a photoperiod of 24L:0D (light/dark). At the same time, 100% survival could be achieved on transfer of the in vitro ginger plantlets with microrhizomes to soil.  相似文献   
30.
Biological Invasions - Fresh waters are among the most endangered ecosystems, one of the problems being the lack of data on biodiversity. In the center of the missing knowledge are cryptic species,...  相似文献   
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