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41.
Mice (DBA/2J) received a Pavlovian procedure in which a distinctive floor stimulus was paired 4 times with ethanol (2 g/kg). A different floor stimulus was paired with saline. Naloxone (0.0, 1.5, or 10.0 mg/kg, intraperitoneal) given before each ethanol trial did not interfere with acquisition of conditioned preference, although naloxone alone produced conditioned aversion. When naloxone (0.0, 0.15, 1.5, 3.0, or 10.0 mg/kg) was given for the first time during testing, mice showed conditioned preference during the first 10 min. However, preference subsequently decreased dose-dependently over time. Control studies eliminated alternative interpretations based on pharmacokinetics or presence of an aversive state. The overall pattern of results suggests that naloxone facilitated extinction of conditioned place preference and supports the hypothesis that ethanol-induced conditioned reinforcement is mediated by the endogenous opioid system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
42.
Most patients relapse after high-dose chemotherapy (HDCT) with autologous stem-cell transplantation (ASCT) for metastatic breast cancer. Further chemotherapy immediately after hematopoietic recovery from ASCT is not given for fear of irreversibly damaging the newly engrafted stem cells. In a pilot chemoprotection trial, autologous CD34+ cells from patients with metastatic breast cancer were exposed to a replication-incompetent retroviral vector carrying MDR-1 cDNA and then reinfused after HDCT. Immediately on recovery, patients received multiple courses of escalating dose paclitaxel. All of the 10 patients tolerated reinfusion of modified cells without any toxicity and had myeloid engraftment within 12 days (range, 11-14). The bone marrow cells of three patients contained vector MDR-1-positive cells only at the time of the first course of posttransplant paclitaxel, indicating that the MDR-1 vector-modified cells had only short-term engrafting potential. A total of 83 courses of paclitaxel were administered starting at a median of 30 (range, 21-32) days from ASCT. The median dose of paclitaxel was 225 mg/m2 and the median interval between paclitaxel cycles of therapy was 21 (range, 20-41) days. Five of the six CR patients were able to receive all of the 12 courses of paclitaxel. Three patients who had achieved less than a complete response to the HDCT (2 patients) and partial response (1 patient) were converted to complete clinical responses during the 12 cycles of paclitaxel. No delayed toxicity or bone marrow failure was noted in these patients with a median follow-up of 2 years from ASCT. This is the first study of chemotherapy immediately after transplantation with autologous CD34+ cells. These data indicate that paclitaxel can be safely administered immediately after ASCT without any delayed toxicities. Paclitaxel given immediately after ASCT can further improve the response to pretransplant chemotherapy in patients with advanced breast cancer.  相似文献   
43.
Our main result is a monogamy inequality satisfied by the entanglement of a focus qubit (one-tangle) in a four-qubit pure state and entanglement of subsystems. Analytical relations between three-tangles of three-qubit marginal states, two-tangles of two-qubit marginal states and unitary invariants of four-qubit pure state are used to obtain the inequality. The contribution of three-tangle to one-tangle is found to be half of that suggested by a simple extension of entanglement monogamy relation for three qubits. On the other hand, an additional contribution due to a two-qubit invariant which is a function of three-way correlations is found. We also show that four-qubit monogamy inequality conjecture of Regula et al. (Phys Rev Lett 113:110501, 2014), in which three-tangles are raised to the power \(\frac{3}{2}\), does not estimate the residual correlations, correctly, for certain subsets of four-qubit states. A lower bound on residual four-qubit correlations is obtained.  相似文献   
44.
This paper presents an analysis, simulation and comparison of the performance of Optical single sideband radio over fiber system based on a dual drive Mach Zehender modulator using 90° and 120° hybrid coupler including the effects of phase noise from RF signal oscillator and laser source, fiber dispersion. Signal to noise ratio (SNR) is significantly influenced by phase noise from RF signal oscillator. On comparison with conventional 90° hybrid coupler system, the performance of the considered system improves by 0.78 dB in terms of SNR, when RF and laser phase noises are increased.  相似文献   
45.
-Copaene, a potent attractant for male Mediterranean fruit flies, Ceratitis capitata, is found as a minor component in the essential oils of various plant species, including its hosts such as orange, guava, and mango. Despite the specific attraction of male flies and the wide distribution of the compound in host plants, the biological significance of -copaene remains unknown. In a laboratory test, leklike behavior of C. capitata was induced artificially by using a plastic leaf model treated with (+)--copaene. It was also found that (+)--copaene affected virgin females, provoking "pseudomale" courtship behavior in the short-range bioassay. Mating occurred exclusively on the artificial leaves treated with -copaene, suggesting the compound potentially serves as a chemical cue to facilitate orientation of flies to the rendezvous site.  相似文献   
46.
Recently, thermal behavior differences between beet and cane sugars have been reported. Generally, cane sugars exhibited two endothermic DSC peaks, one small peak proceeded by one large peak; whereas, beet sugars exhibited only one large endothermic DSC peak. Previous research linked the presence of the small peak to the appearance of thermal decomposition components in analytical grade cane sucrose. However, no research was found exploring this relation for other sucrose sources. Thus, our objective was to investigate the possible association between the aforementioned DSC curve differences and the appearance of selected thermal decomposition components in a wide variety of sucrose samples, including analytical grade cane, white refined commercial beet and cane, and laboratory-recrystallized beet, using HPLC analysis. A strong, predictive relation between the DSC Tmonset value and the temperature at which the initial thermal decomposition component(s) (TDConset) was detected was found for both beet and cane sugars. DSC Tmonset and TDConset values occurred at substantially lower temperatures for cane (150 °C to 160 °C and 170 °C, respectively) compared to beet (188 °C and 200 °C, respectively) samples, establishing that, overall, beet sucrose sources exhibit greater thermal stability than cane. We hypothesize that this wide variation in thermal stability is related to differences in crystal composition and chemistry and merit further investigation. Understanding the thermal behavior differences between and within beet and cane sugars and the potential impact on processing of sugar containing products is of substantial value to the food industry, and suggests that additional factors besides market price need to be taken into consideration during sucrose source selection.  相似文献   
47.
Photonic Network Communications - This paper provides an overview of linearization of two different microwave photonic links based on phase modulator and dual-electrode Mach–Zehnder...  相似文献   
48.
Microsystem Technologies - A new interface circuit for readout of HgCdTe Infrared photodiodes is proposed that can be used for efficient transfer of photocurrent from the photodiodes to the...  相似文献   
49.
50.
Beet sugar contains an off‐aroma, which was hypothesized to generate expectations on the acceptability of a product made with beet sugar. Thus, the objective of this study was to assess the impact of information about the sugar source (beet vs. cane) on the overall liking of an orange‐flavored beverage. One hundred panelists evaluated an orange‐flavored powdered beverage mix and beverage made with beet and cane sugars using a 5‐phase testing protocol involving a tetrad test and hedonic ratings performed under blind and informed conditions. Tetrad test results indicated that there was a significant difference (P < 0.05) between the beverage mix made with beet sugar and cane sugar; however, no difference was found between the beverage made with beet sugar and cane sugar. Hedonic ratings revealed the significance of information conditions on the panelists evaluation of sugar (F = 24.67, P < 0.001); however, no difference in the liking was identified for the beverage mix or beverage. Average hedonic scores were higher under informed condition compared to blind condition for all products, possibly because labels tend to reduce uncertainty about a product. Results from this study are representative of the responses from the general population and suggest that they are not affected by sugar source information in a beverage product. Based on concerns with the use of beet sugar expressed in the popular press, there may be a subgroup of the population that has a preconceived bias about sugar sources due to their prior experiences and knowledge and, thus, would be influenced by labels indicating the sugar source used in a product.  相似文献   
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