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991.
EktacytometrymeasuringRBCdeformabilitywasfirstdevelopedbyBessisetal.in1975[1].Thistechniquehasbeenworldwideacceptednow.However,themeaningofdeformationindex(DI)measuredwiththismethodisstillworthstudying.ThetraditionalEktacytometryusessuspendingmediumofhighvi… 相似文献
992.
Shi Yong-Xin; Seto-Poon Margaret; Wheatley John R. 《Journal of applied physiology》1998,84(5):1701-1706
Exercise (Ex) and hypercapnia (HC) both lead toincreases in ventilation and upper airway muscle (UAM) activity. Todetermine whether different breathing routes (nasal vs. oral) orstimuli produced differential UAM activation, electromyographic (EMG) activity of the alae nasi (AN) and genioglossus (GG) were measured inseven normal subjects seated on a bicycle ergometer. Subjects performedpaired runs during both progressive Ex and HC while breathing throughthe nose alone (N) or the mouth alone (O). During hyperpnea, AN EMG wasgreater when the subjects were breathing via N [81 ± 6%maximum (HC) and 69 ± 7% maximum (Ex)] than when they werebreathing via O [30 ± 5% maximum (HC) and 27 ± 5%maximum (Ex); both P < 0.01],whereas the GG EMG did not differ between N and O. Both AN and GG EMGwere similar for Ex and HC when the subjects were breathing via thesame route. We conclude that UAM activation was independent of thenature of the stimulus. However, the AN muscle but not the GG muscledemonstrated breathing-route dependence of activity. 相似文献
993.
Effect of hypohydration on gastric emptying and intestinal absorption during exercise 总被引:1,自引:0,他引:1
Ryan A. J.; Lambert G. P.; Shi X.; Chang R. T.; Summers R. W.; Gisolfi C. V. 《Journal of applied physiology》1998,84(5):1581-1588
Dehydration and hyperthermia may impair gastricemptying (GE) during exercise; the effect of these alterations onintestinal water flux (WF) is unknown. Thus the purpose of this studywas to determine the effect of hypohydration (~2.7% body weight) on GE and WF of a water placebo (WP) during cycling exercise (85 min, 65%maximal oxygen uptake) in a cool environment (22°C) and to alsocompare GE and WF of three carbohydrate-electrolyte solutions (CES)while the subjects were hypohydrated. GE and WF were determined simultaneously by a nasogastric tube placed in the gastric antrum andvia a multilumen tube that spanned the duodenum and the first 25 cm ofjejunum. Hypohydration was attained 12-16 h before experiments bylow-intensity exercise in a hot (45°C), humid (relative humidity 50%) environment. Seven healthy subjects (age 26.7 ± 1.7 yr,maximal oxygen uptake 55.9 ± 8.2 ml · kg1 · min1)ingested either WP or a 6% (330 mosmol), 8% (400 mosmol), or a 9%(590 mosmol) CES the morning following hypohydration. For comparison,subjects ingested WP after a euhydration protocol. Solutions (~2.0liters total) were ingested as a large bolus (4.6 ml/kg body wt) 5 minbefore exercise and as small serial feedings (2.3 ml/kg body wt) every10 min of exercise. Average GE rates were not different amongconditions (P > 0.05). Mean(±SE) values for WF were also similar(P > 0.05) for the euhydration (15.3 ± 1.7 ml · cm1 · h1)and hypohydration (18.3 ± 2.6 ml · cm1 · h1)experiments. During exercise after hypohydration, waterabsorption was greater (P < 0.05)with ingestion of WP (18.3 ± 2.6) and the 6% CES (16.5 ± 3.7),compared with the 8% CES (6.9 ± 1.5) and the 9% CES (1.8 ± 1.7). Mean values for final core temperature (38.6 ± 0.1°C),heart rate (152 ± 1 beats/min), and change in plasma volume(5.7 ± 0.7%) were similar among experimental trials. Weconclude that 1) hypohydration to~3% body weight does not impair GE or fluid absorption duringmoderate exercise when ingesting WP, and2) hyperosmolality (>400 mosmol)reduced WF in the proximal intestine. 相似文献
994.
Thermal stresses were studied in freezing of biomaterials containing significant amounts of water. An apparent specific heat formulation of the energy equation and a viscoelastic model for the mechanics problem were used to analyze the transient axi-symmetric freezing of a long cylinder. Viscoelastic properties were measured in an Instron machine. Results show that, before phase change occurs at any location, both radial and circumferential stresses are tensile and keep increasing until phase change begins. The maximum principal tensile stress during phase change increases with a decrease in boundary temperature (faster cooling). This is consistent with experimentally observed fractures at a lower boundary temperature. Large volumetric expansion during water to ice transformation was shown to be the primary contributor to large stress development. For very rapid freezing, relaxation may not be significant, and an elastic model may be sufficient. 相似文献
995.
The relation between the fast phase of ms-DLE (delayed light emission measured with a phosphoroscope) and the proton released from water oxidation in spinach chloroplasts was studied in several aspects. When photophosphorylation was allowed to be coupled to the Hill reaction the intensity of the fast phase of ms-DLE of chloroplast was lowered more at 1 °C than at 25 °C, and the photophosphorylation rate within 40 ms of flashing light was higher at 1 °C than at 25 °C. Adding the subunit of ATP synthase to the chloroplast preparation to block the leakage of protons through ATP synthase, the intensity of the fast phase of ms-DLE was enhanced, to a larger extent at 1 °C than at 25°C. When the ms-DLE was measured under isotonic conditions, the intensity of fast phase of ms-DLE enhanced by proton released from oxidation of water was more pronounced. The above results support the suggestion that under lower temperature and isotonic conditions, the proton released from water oxidation was liable to be localized and could enhance the intensity of the fast phase of ms-DLE more effectively. 相似文献
996.
997.
Rong Li Xiao‐Ling Tang Shi‐Ying Miao Shu‐Dong Zong Lin‐Fang Wang 《Cell biochemistry and function》2009,27(5):264-268
Sperm associated antigen 8 (SPAG8), a testis‐specific protein produced during male germ cell differentiation, was isolated from a human testis expression library using antibodies found in the serum obtained from an infertile woman. It was found to have a close functional relationship with microtubules. In this study, we generated a stably expressing SPAG8 CHO‐K1 cell line. Immunofluorescence confocal microscopy showed that SPAG8 was concentrated at the microtubule‐organizing center (MTOC) during prophase. As the cells progressed into metaphase, it co‐localized with α‐tubulin on the spindle. In anaphase, it was detected on both astral microtubules and mid‐zone. Following cytokinesis, SPAG8 resumed its localization on the MTOC. Meanwhile, flow cytometry analysis found that SPAG8 prolonged the G2/M phase of CHO‐K1 cells stably expressing SPAG8. Furthermore, 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay showed that SPAG8 inhibited the proliferation of the stable cells. SPAG8 might be involved in the regulation of cell cycle by changing the phosphorylation level of Tyr15 on cdc2. These results suggest that SPAG8 might play a role in cell division during spermatogenesis. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
998.
Antoine Tesniere Ann‐Charlotte Bjorklund Daniel C Chapman Michael Durchschlag Nicholas Joza Gérard Pierron Peter van Endert Junying Yuan Laurence Zitvogel Frank Madeo David B Williams Guido Kroemer 《The EMBO journal》2009,28(5):578-590
Dying tumour cells can elicit a potent anticancer immune response by exposing the calreticulin (CRT)/ERp57 complex on the cell surface before the cells manifest any signs of apoptosis. Here, we enumerate elements of the pathway that mediates pre‐apoptotic CRT/ERp57 exposure in response to several immunogenic anticancer agents. Early activation of the endoplasmic reticulum (ER)‐sessile kinase PERK leads to phosphorylation of the translation initiation factor eIF2α, followed by partial activation of caspase‐8 (but not caspase‐3), caspase‐8‐mediated cleavage of the ER protein BAP31 and conformational activation of Bax and Bak. Finally, a pool of CRT that has transited the Golgi apparatus is secreted by SNARE‐dependent exocytosis. Knock‐in mutation of eIF2α (to make it non‐phosphorylatable) or BAP31 (to render it uncleavable), depletion of PERK, caspase‐8, BAP31, Bax, Bak or SNAREs abolished CRT/ERp57 exposure induced by anthracyclines, oxaliplatin and ultraviolet C light. Depletion of PERK, caspase‐8 or SNAREs had no effect on cell death induced by anthracyclines, yet abolished the immunogenicity of cell death, which could be restored by absorbing recombinant CRT to the cell surface. 相似文献
999.
Efficient,Large Area,and Thick Junction Polymer Solar Cells with Balanced Mobilities and Low Defect Densities 下载免费PDF全文
Ardalan Armin Mike Hambsch Pascal Wolfer Hui Jin Jun Li Zugui Shi Paul L. Burn Paul Meredith 《Liver Transplantation》2015,5(3)
The high power conversion efficiencies (PCEs) of laboratory‐scale polymer‐based organic solar cells are yet to translate to large area modules because of a number of factors including the relatively large sheet resistance of available transparent conducting electrodes (TCEs), and the high defect densities associated with thin organic semiconductor junctions. The TCE problem limits device architectures to narrow connected strips (<1 cm) causing serious fabrication difficulties and extra costs. Thin junctions are required because of poor charge transport (imbalanced mobilities) in the constituent organic semiconductors. These issues are addressed using a combination of approaches to create thick junctions conformally coated on low sheet resistance metal grid TCEs. An essential feature of these thick junctions is balanced carrier mobilities, which affords high fill factors and efficient carrier extraction. Conformal coating is achieved by promoting enhanced intermolecular interactions in the coating solution using a high molecular weight polymeric semiconductor and appropriate solvent system. This combination of balanced mobilities, conformal coating and metallic grid TCEs is a simple and generic approach to the fabrication of defect‐free large area organic solar cells (OSCs). The approach is demonstrated with 25 cm2 monolithic devices possessing aperture‐corrected power conversion efficiencies of 5% and fill factors exceeding 0.5. 相似文献
1000.