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101.
Borderline ovarian tumors are a low grade form of epithelial ovarian carcinoma with a low rate of growth and a low potential to invade or metastasize. According to the new World Health Organization classification, these tumors are placed between clearly benign and obviously malignant tumors because they exhibit some, but not all, of the morphologic features of malignancy. For a distinction between borderline lesions and cystadenomas or carcinomas, 2 criteria are of the utmost importance: presence of nuclear atypia and absence of stromal invasion. The pathologic subtype ofperitoneal implants is probably one of the main prognosticfactors in patients with serous tumors of low malignant potential, while the prognostic value of micropapillary serous carcinoma in patients with noninvasive implants remains debatable. Although fine needle aspiration (FNA) is the most accurate diagnostic method in cytopathology, its value in the diagnosis of borderline lesions is limited, mainly because of its inability to establish the absence of stromal invasion. The diagnostic accuracy of RNA can be improved by supplementing cytologic examination with such diagnostic techniques as immunocytochemistry and cytometry.  相似文献   
102.
A QSAR analysis for substituted (S)-phenylpiperidines as dopamine (DA) antagonists is described. The studied derivatives differ at the nitrogen substitutent (R) and at the substitutents (X) of the phenyl-ring. The analysis was done using the C-QSAR suite program (Biobyte) through the Internet. Clog P, CMR, M(vol), B1 and L (the Verloop's sterimol parameters for the substitutents) were used as parameters. In all the three studied cases clog P plays a significant part in the QSAR of DA antagonists, followed by the steric factors. In one case the electronic effect contributes significantly.  相似文献   
103.
Mice with a knock-in mutation (Y524S) in the type I ryanodine receptor (Ryr1), a mutation analogous to the Y522S mutation that is associated with malignant hyperthermia in humans, die when exposed to short periods of temperature elevation (≥37 °C). We show here that treatment with 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) prevents this heat-induced sudden death in this mouse model. The protection by AICAR is independent of AMP-activated protein kinase (AMPK) activation and results from a newly identified action of the compound on mutant Ryr1 to reduce Ca(2+) leak from the sarcoplasmic reticulum to the sarcoplasm. AICAR thus prevents Ca(2+)-dependent increases in the amount of both reactive oxygen species (ROS) and reactive nitrogen species (RNS) that act to further increase resting Ca(2+) concentrations. If unchecked, the temperature-driven increases in resting Ca(2+) concentrations and the amounts of ROS and RNS create an amplifying cycle that ultimately triggers sustained muscle contractions, rhabdomyolysis and death. Although antioxidants are effective in reducing this cycle in vitro, only AICAR prevents heat-induced death in vivo. Our findings suggest that AICAR is probably effective in prophylactic treatment of humans with enhanced susceptibility to exercise- and/or heat-induced sudden death associated with RYR1 mutations.  相似文献   
104.
Lake Pamvotis is a moderately sized (22 km2) shallow (z avg=4 m) lake with a polymictic stratification regime located in northwest Greece. The lake has undergone cultural eutrophication over the past 40 years and is currently eutrophic (annual averages of FRP=0.07 mg P l-1, TP=0.11 mg P l-1, NH4 +=0.25 mg N l-1, NO3 =0.56 mg N l-1). FRP and NH4 + levels are correlated to external loading from streams during the winter and spring, and to internal loading during multi-day periods of summer stratification. Algal blooms occurred in summer (July–August green algae, August–September blue-green algae), autumn (October blue-green algae and diatoms), and winter (February diatoms), but not in the spring (March–June). The phytoplankton underwent brief periods of N- and P-limitation, though persistent low transparency (secchi depth of 60–80 cm) also suggests periods of light limitation. Rotifers counts were highest from mid-summer to early autumn whereas copepods were high in the spring and cladocerans were low in the summer. Removal of industrial and sewage point sources a decade ago resulted in a decrease in FRP. A phosphorus mass balance identified further reductions in external loading from the predominately agricultural catchment will decrease FRP levels further. The commercial fishery and lake hatchery also provides opportunities to control algal biomass through biomanipulation measures.  相似文献   
105.
Cannabinoid receptors 1 (CB1Rs) play important roles in the regulation of dendritic branching, synapse density, and synaptic transmission through multiple G-protein-coupled signaling systems, including the activation of the extracellular signal-regulated kinases ERK1/2. The proximal signaling interactions leading to ERK1/2 activation by CB1R in CNS remain, however, unclear. Here, we present evidence that the CB1R agonist methanandamide induced a biphasic and sustained activation of ERK1/2 in primary neurons derived from E7 telencephalon. We show that E7 neurons natively express high levels of CB1R message and protein, the majority of which associates with PKC? at basal conditions. We now demonstrate that the first peak of ERK activation by CB1R was mediated by the sequential activation of G(q), PLC, and PKC?, selectively, and that the CB1R-activated PKC? acutely formed transient signaling modules containing activated Src and Fyn. A second pool of CB1Rs, coupled to PTX-sensitive activation of G(i/o), utilized as effectors additional Src and Fyn molecules to generate a second, additional wave of ERK activation at 15 min. Concurrently to these intermolecular signaling interactions, cytoskeleton-associated proteins MARCKS and p120catenin were drastically modified by phosphorylation of PKC and Src, respectively. These receptor-proximal signaling events correlated well with induction of neuritic outgrowth in the long term. Our data provide evidence for multiprotein signaling complex formation in the coupling of CB1R to activation of ERK in CNS neurons, and may elucidate several of the less understood acute effects of cannabinoid drugs.  相似文献   
106.
Highly efficient and stable organic photovoltaic (OPV) cells are demonstrated by incorporating solution‐processed hydrogen molybdenum bronzes as anode interlayers. The bronzes are synthesized using a sol‐gel method with the critical step being the partial oxide reduction/hydrogenation using an alcohol‐based solvent. Their composition, stoichiometry, and electronic properties strongly correlate with the annealing process to which the films are subjected after spin coating. Hydrogen molybdenum bronzes with moderate degree of reduction are found to be highly advantageous when used as anode interlayers in OPVs, as they maintain a high work function similar to the fully stoichiometric metal oxide, whereas they exhibit a high density of occupied gap states, which are beneficial for charge transport. Enhanced short‐circuit current, open‐circuit voltage and, fill factor, relative to reference devices incorporating either PEDOT‐PSS or a solution processed stoichiometric molybdenum oxide, are obtained for a variety of bulk heterojunction mixtures based on different polymeric donors and fullerene acceptors. In particular, high power conversion efficiencies are obtained in devices that employed the s‐HxMoO2.75 as the hole extraction layer.  相似文献   
107.
A cell-free system derived from Dictyostelium discoideum has been used to study the kinetics of inhibition of RNase P by puromycin, amicetin and blasticidin S. Detailed kinetic analysis showed that the type of inhibition of RNase P activity by puromycin is simple competitive, whereas the type of inhibition by amicetin and blasticidin S is simple non-competitive. On the basis of Ki values amicetin is stronger inhibitor than puromycin and blasticidin S.  相似文献   
108.
109.
Bacterial peptide display libraries enable the rapid and efficient selection of peptides that have high affinity and selectivity toward their targets. Using a 15‐mer random library on the outer surface of Escherichia coli (E.coli), high‐affinity peptides were selected against a staphylococcal enterotoxin B (SEB) protein after four rounds of biopanning. On‐cell screening analysis of affinity and specificity were measured by flow cytometry and directly compared to the synthetic peptide, off‐cell, using peptide‐ELISA. DNA sequencing of the positive clones after four rounds of microfluidic magnetic sorting (MMS) revealed a common consensus sequence of (S/T)CH(Y/F)W for the SEB‐binding peptides R338, R418, and R445. The consensus sequence in these bacterial display peptides has similar amino acid characteristics with SEB peptide sequences isolated from phage display. The Kd measured by peptide‐ELISA off‐cell was 2.4 nM for R418 and 3.0 nM for R445. The bacterial peptide display methodology using the semiautomated MMS resulted in the discovery of selective peptides with affinity for a food safety and defense threat. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. Journal of Molecular Recognition published by John Wiley & Sons, Ltd.  相似文献   
110.
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