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121.
Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most common way of treating inflammatory disorders. Their widespread use helped reveal their other modes of action as pharmaceuticals, such as a profound effect on various cancers. Celecoxib has proven to be a very prominent member of this group with cytostatic activities. On the other hand, the highly dynamic field of drug design is constantly searching for new ways of modifying known structures to obtain more powerful and less harmful drugs. A very interesting development is the implementation of carboranes in pharmacologically active structures, mostly as phenyl mimetics. Herein we report the synthesis of three carborane-containing derivatives of the COX-2-selective NSAID celecoxib. The new compounds proved to have promising cytostatic potential against various melanoma and colorectal adenocarcinoma cell lines. Inhibited proliferation accompanied by caspase-independent apoptotic cell death was found to be the main cause of decreased cell viability upon treatment with the most efficient celecoxib analogue, 3 b (4-[5-(1,7-dicarba-closo-dodecaboranyl)-3-trifluoromethyl-1H-pyrazol-1-yl]-1-methylsulfonylbenzene).  相似文献   
122.
Anxiety about separation from a child is highly salient to parents and, when studied in mothers, has been shown to relate to important personality attributes. This longitudinal study examined origins of separation anxiety, describing the course and significance of separation anxiety in parents of firstborn infants. Although no gender effects were found in mean levels of separation anxiety across the 1st 2 years of parenthood, regression analyses revealed different patterns of relations between separation anxiety and psychological and contextual variables for men and women. For men, only self-criticism and their wife's separation anxiety were significant; for women, separation anxiety was related to personality attributes (such as dependency and self-criticism), role-related beliefs, their spouse's anxiety about separation, and the unique health characteristics of their child. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
123.
Cyclooxygenase (COX) is an enzyme involved in tumorigenesis and is associated with tumor cell resistance against platinum‐based antitumor drugs. Cisplatin analogues were conjugated with COX inhibitors (indomethacin, ibuprofen) to study the synergistic effects that were previously observed in combination treatments. The conjugates ensure concerted transport of both drugs into cells, and subsequent intracellular cleavage enables a dual‐action mode. Whereas the platinum(II) complexes showed cytotoxicities similar to those of cisplatin, the platinum(IV) conjugates revealed highly increased cytotoxic activities and were able to completely overcome cisplatin‐related resistance. Although some of the complexes are potent COX inhibitors, the conjugates appear to execute their cytotoxic action via COX‐independent mechanisms. Instead, the increased lipophilicity and kinetic inertness of the conjugates seem to facilitate cellular accumulation of the platinum drugs and thus improve the efficacy of the antitumor agents. These conjugates are important tools for the elucidation of the direct influence of COX inhibitors on platinum‐based anticancer drugs in tumor cells.  相似文献   
124.
The suitability of DNA present in olive oil for PCR analysis has been reported by several authors. However, low concentration, degradation, and the possible presence of additional alleles due to paternal contribution in oils extracted from entire drupes, should be taken into consideration when comparing the amplification profiles of leaves with the corresponding oils for varietal traceability purposes. The aim of this work was to assess, by capillary electrophoresis of microsatellite markers, the phenetic relationships among seven certified Olea europaea L. cultivars, and to verify the genomic equality between leaf DNA and the corresponding monovarietal oil DNA. Moreover, the aim was to establish an identification key to distinguish all the types of oil among them with the minimum number of markers. The results referred to oil DNA, obtained in 70 PCR experiments, confirmed the possibility, in 85.7% of cases, of extracting DNA suitable for the analysis of microsatellites. Ninety percent of the successful amplifications led to identical patterns for leaves and oil DNA. Cima di Melfi shared only 20% of the alleles with the other cultivars. Toscanina and Leccino, showed the highest similarity (about 60%). A single microsatellite was able to distinguish the seven types of oil.  相似文献   
125.
This study examined whether getting divorced was related to the subsequent incidence of DSM-III-R disorders across a 2-year period, controlling for the perceived quality of the marriage prior to the divorce. Data were used from 4,796 adults aged 18 to 64, who had participated in 3 waves (i.e., 1996, 1997, and 1999) of a large-scale epidemiological study conducted in The Netherlands. Results showed that getting divorced was prospectively linked to both the total and new case incidence of alcohol abuse and dysthymia, as well as to the new case incidence of social phobia. Adults who had divorced, however, were not more likely to develop a mental disorder if they had reported low levels of marital quality prior to the divorce. Thus, the marital discord underlying a divorce rather than divorce itself appeared to determine the onset of clinically relevant mental health problems. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
126.
The Global Tracking Trigger (GTT) of the ZEUS experiment is described. The GTT is data driven at the ZEUS first level trigger rate of and performs event-based track finding on data from the experiment's Central Tracking Detector (CTD), silicon Micro Vertex Detector (MVD) and Straw Tube Tracker (STT) forward detectors. The resulting track-based trigger quantities calculated (track multiplicity, vertices, vector meson masses, background event probabilities, etc.) are available within and are used in the experiment's second level trigger to improve the selection of physics events. Detector information is pushed to the PC farm of the GTT using PowerPC VME board computers which are either embedded within the detector's frontend readout system (MVD) or are parasitically attached to them via multiple serial transputer links (CTD and STT). Data flow and control is performed via point-to-point Fast and Giga ethernet switched network connections using the TCP protocol. The principal design challenges were: integrating new and interfacing to existing frontend systems, providing a useful trigger result, satisfying the rate and latency requirements and not interfering with ongoing data taking during commissioning. These aims have been achieved. The GTT has been actively used in the ZEUS trigger since 2004 when an initial CTD-only algorithm was used; in 2005 this was upgraded to use MVD information which significantly improves track and primary vertex resolutions. Commissioning problems delayed the STT implementation and its use in the GTT has only been tested.  相似文献   
127.
In this study, the authors examined cross-sectional and longitudinal associations between late adolescents' parental attachment and emotional disturbance. Specifically, they investigated whether associations between parental attachment and emotional disturbance were less strong for adolescents with romantic partners, and whether the quality and duration of romantic relationships were related to adolescents' emotional disturbance. Data were collected from 568 adolescents, ages 15-19, interviewed in 1994 and 1997. Cross-sectional analyses showed significant associations between parental attachment and emotional disturbance, but no systematic longitudinal relationships were found. Links cross-sectionally, but not longitudinally, between parental attachment and emotional disturbance were less strong for youths with romantic partners. Neither the quality nor the duration of romantic relationships was related to emotional disturbance in this age group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
128.
During mating in many butterfly species, males transfer spermatophores that contain anti-aphrodisiacs to females that repel conspecific males. For example, males of the large cabbage white, Pieris brassicae (Lepidoptera: Pieridae), transfer the anti-aphrodisiac, benzyl cyanide (BC) to females. Accessory reproductive gland (ARG) secretion of a mated female P. brassicae that is deposited with an egg clutch contains traces of BC, inducing Brussels sprouts plants (Brassica oleracea var. gemmifera) to arrest certain Trichogramma egg parasitoids. Here, we assessed whether deposition of one egg at a time by the closely related small cabbage white, Pieris rapae, induced B. oleracea var. gemmifera to arrest Trichogramma wasps, and whether this plant synomone is triggered by substances originating from male P. rapae seminal fluid. We showed that plants induced by singly laid eggs of P. rapae arrest T. brassicae wasps three days after butterfly egg deposition. Elicitor activity was present in ARG secretion of mated female butterflies, whereas the secretion of virgin females was inactive. Pieris rapae used a mixture of methyl salicylate (MeSA) and indole as an anti-aphrodisiac. We detected traces of both anti-aphrodisiacal compounds in the ARG secretion of mated female P. rapae, whereas indole was lacking in the secretion of virgin female P. rapae. When applied onto the leaf, indole induced changes in the foliar chemistry that arrested T. brassicae wasps. This study shows that compounds of male seminal fluid incur possible fitness costs for Pieris butterflies by indirectly promoting egg parasitoid attack.  相似文献   
129.
Cyberostracism: Effects of being ignored over the Internet.   总被引:1,自引:0,他引:1  
Ostracism is such a widely used and powerful tactic that the authors tested whether people would be affected by it even under remote and artificial circumstances. In Study 1, 1,486 participants from 62 countries accessed the authors' on-line experiment on the Internet. They were asked to use mental visualization while playing a virtual tossing game with two others (who were actually computer generated and controlled). Despite the minimal nature of their experience, the more participants were ostracized, the more they reported feeling bad, having less control, and losing a sense of belonging. In Study 2, ostracized participants were more likely to conform on a subsequent task. The results are discussed in terms of supporting K. D. Williams's (1997) need threat theory of ostracism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
130.
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