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1.
Metabolism is recognized as an important driver of cancer progression and other complex diseases, but global metabolite profiling remains a challenge. Protein expression profiling is often a poor proxy since existing pathway enrichment models provide an incomplete mapping between the proteome and metabolism. To overcome these gaps, we introduce multiomic metabolic enrichment network analysis (MOMENTA), an integrative multiomic data analysis framework for more accurately deducing metabolic pathway changes from proteomics data alone in a gene set analysis context by leveraging protein interaction networks to extend annotated metabolic models. We apply MOMENTA to proteomic data from diverse cancer cell lines and human tumors to demonstrate its utility at revealing variation in metabolic pathway activity across cancer types, which we verify using independent metabolomics measurements. The novel metabolic networks we uncover in breast cancer and other tumors are linked to clinical outcomes, underscoring the pathophysiological relevance of the findings.  相似文献   
2.
Extremely miniaturized longipedes insects (body length c. 0.3 mm) embedded in two pieces of Cretaceous amber from Myanmar are described and interpreted. Using inverted fluorescence and light microscopy for detailed analysis of microstructures, the inclusions were identified as primary larvae of the beetle family Ripiphoridae, subfamily Ripidiinae. While the structure of thoracic and abdominal segments including appendages corresponds well with the groundplan known in recent members of Ripidiinae, a curved prosternal ridge with prominent spines (each c. 5 μm), the reduced condition of stemmata and antennae and the lack of sharp mandibles are unique features within the entire family, apparently apomorphies of the longipedes larvae. A sinuate prosternal edge with a dense row of spines (prosternoctenidium) might be homologous with ‘head ctenidia’ in some previously described miniaturized conicocephalate larvae, but further investigation is needed. The morphological differences between the head of longipedes larvae and extant Ripidiinae are interpreted as adaptations to different groups of hosts and life strategies. Palaeoethology of the longipedes larvae is briefly discussed. In addition, the systematic placement of conicocephalate larvae from Canadian, Myanmar and Russian Cretaceous ambers, already interpreted by various authors as primary instars within Coleopterida (assigned to either Strepsiptera or to the coleopteran Tenebrionoidea: Ripiphoridae), is discussed.  相似文献   
3.
In several geographic populations of the Arctic ground squirrel C. parryi, studies have been made on changes in oxygen consumption during decrease of the ambient temperature from 25 to 3-4 degrees, thermal preference, hemoglobin content of the blood and composition of the adipose tissue (both brown and white, subcutaneous and visceral). Significant shifts of these indices were found. In animals from various parts of the species area, different sensitivity to cooling was found, as indicated by determinations of oxygen consumption at different temperatures and the prefered temperature: different hemoglobin content of the blood was also found together with differences in the level of two unsaturated fatty acids - the oleic and linoleic ones. Comparison of these data with similar results obtained on various populations of the Siberian ground squirrel C. undulatus revealed obvious differences between these close species with respect to the indices studied.  相似文献   
4.
The respiration chain in the membranes of whole Actinomyces roseoflavus (var. roseofungini) cells from the parent and secondary cultures is sensitive to KCN, non-sensitive to Triton X-100 treatment removing the antibiotic roseofungin from the cells, and has a very high for the bacteria respiration control. When the cells are in contact with atomic tritium at the temperature of liquid nitrogen, roseofungin is tritiated and binds to A. roseoflavus isolated membranes and whole cells, mostly to those of the parent culture as compared to the secondary culture. A fraction of membranes which lost NADH dehydrogenase in the course++ of purification was isolated from the cells disintegrated in the frozen state.  相似文献   
5.
The results of treating 322 patients with various forms of meningococcal infection accepted to a hospital within a year are presented. The patients were divided into 3 groups by the character of etiotropic therapy. The patients of group I were treated with benzylpenicillin and those of group 2 were treated with levomycetin sodium succinate. Group 3 included the patients, the therapy of whom with the above two antibiotics failed and they were subjected to treatment with cefazolin, cefotaxime, amikacin and other broad spectrum antibiotics. Benzylpenicillin generally proved to be the drug of choice in the antibacterial therapy of meningococcal infection. In comparison to levomycetin (chloramphenicol) it provide more rapid clinical recovery of the patients and normalization of the indices of the cerebrospinal fluid. Only failure of benzylpenicillin therapy was considered as an indication to the broad-spectrum antibiotics to be in the complex treatment of the patients. As additional methods for estimating the efficacy of antibacterial therapy it was recommended to employ calculation of the integral indices of hemograms (the leukocyte index of intoxication and the hematologic index of intoxication).  相似文献   
6.
The binding of cGMP by structural components of bovine rod outer segments was studied. The discs and plasma membranes were shown to contain two types of the specific binding sites for cGMP which are distinct from cyclic GMP phosphodiesterase. The sites have a "high" and "low" (Kd = 0.1 divided by 0.35 and 1.5 divided by 2.0 X 10(-6) M respectively) affinity for cGMP. They belong to membraneous integral proteins presumably associated with phospholipids. Their affinity for cGMP is controlled by GTP and calmodulin.  相似文献   
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Collapsible-tube flow with self-excited oscillations has been extensively investigated. Though physiologically relevant, forced oscillation coupled with self-excited oscillation has received little attention in this context. Based on an ODE model of collapsible-tube flow, the present study applies modern dynamics methods to investigate numerically the responses of forced oscillation to a limit-cycle oscillation which has topological characteristics discovered in previous unforced experiments. A devil's staircase and period-doubling cascades are presented with forcing frequency and amplitude as control parameters. In both cases, details are provided in a bifurcation diagram. Poincaré sections, a frequency spectrum and the largest Lyapunov exponents verify the existence of chaos in some circumstances. The thin fractal structure found in the strange attractors is believed to be a result of high damping and low stiffness in such systems.  相似文献   
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