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Journal of Chemical Ecology - The obligate pollination mutualism between Yucca and yucca moths is a classical example of coevolution. Oviposition and active pollination by female yucca moths occur...  相似文献   
2.
Designer and computational specialist Daniel Segraves describes the decarbonisation tool that he has helped develop in collaboration with Chicago-based Adrian Smith + Gordon Gill Architects and the Argonne National Laboratory Computation Department. The creation of the multi-scale analytic model focusing on the embodied and expended carbon of urban systems allows for energy performance to be tracked across a wider region, encompassing multiple buildings and agents.  相似文献   
3.
Adult smokers (N?=?253) without clinically significant depression were randomized on a double-blind basis to receive fluoxetine (30 or 60 mg daily) or a placebo for 10 weeks in combination with cognitive-behavioral therapy (CBT). It was predicted that fluoxetine would selectively benefit smokers with higher baseline depression, nicotine dependence, and weight concern and lower self-efficacy about quitting smoking. Among those who completed the prescribed treatment regimen, baseline depression scores moderated the treatment response. Logistic regression analyses showed that 1 and 3 months after the quit date, fluoxetine increased the likelihood of abstinence, as compared with placebo, among smokers with minor depression but not among those with little or no depression. Results suggest that, as an adjunct to CBT, fluoxetine enhances cessation by selectively benefiting medication-compliant smokers who display even subclinical levels of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
BACKGROUND: A sustained-release formulation of bupropion (bupropion SR), developed with an improved pharmacokinetic profile to permit less frequent dosing than the immediate-release form, has not been evaluated in active comparator trials. This randomized, double-blind, parallel-group trial was conducted to compare the efficacy and safety of bupropion SR and sertraline. METHOD: Outpatients with moderate to severe major depressive disorder (DSM-IV) received bupropion SR (100-300 mg/day) or sertraline (50-200 mg/day) for 16 weeks. Psychiatric evaluations, including the Hamilton Rating Scale for Depression (HAM-D), the Hamilton Rating Scale for Anxiety (HAM-A), the Clinical Global Impressions scale for Severity of Illness (CGI-S), and for Improvement (CGI-I) were completed, and adverse events were assessed in the clinic periodically throughout treatment. Patients' orgasm function was also assessed. RESULTS: Mean HAM-D, HAM-A, CGI-I, and CGI-S scores improved over the course of treatment in both the bupropion SR group and the sertraline group; no between-group differences were observed on any of the scales. Orgasm dysfunction was significantly (p < .001) more common in sertraline-treated patients compared with bupropion SR-treated patients. The adverse events of nausea, diarrhea, somnolence, and sweating were also experienced more frequently (p < .05) in sertraline-treated patients. No differences were noted between the two treatments for vital signs and weight. CONCLUSION: This double-blind comparison of bupropion SR and sertraline demonstrates that bupropion and sertraline are similarly effective for the treatment of depression. Both compounds were relatively well tolerated, and orgasm dysfunction, nausea, diarrhea, somnolence, and sweating were reported more frequently in sertraline-treated patients.  相似文献   
5.
Simultaneous recordings were collected from between two and four buildup neurons from the left and right superior colliculi in rhesus monkeys in a simple two-choice brightness discrimination task. The monkeys were required to move their eyes to one of two response targets to indicate their decision. Neurons were identified whose receptive fields were centered on the response targets. The functional role of inhibition was examined by conditionalizing firing rate on a high versus low rate in target neurons 90 ms to 30 ms before the saccade and examining the firing rate in both contralateral and ipsilateral neurons. Two models with racing diffusion processes were fit to the behavioral data, and the same analysis was performed on simulated paths in the diffusion processes that have been found to represent firing rate. The results produce converging evidence for the lack of a functional role for inhibition between neural populations corresponding to the two decisions.  相似文献   
6.
1. This project tests the behavioral effects of reversible activation and inactivation of sites within the frontal eye field of rhesus monkeys with microinjections of the gamma-aminobutyric acid (GABA)-related drugs bicuculline and muscimol. 2. Muscimol injections impaired the monkeys' ability to make both visually and memory-guided saccades to targets at the center of the area represented by the injection site. The latencies of saccades to targets in regions flanking the injection were increased. For memory-guided saccades, saccades in the direction opposite to that represented by the injection site, were made with shorter latency than controls and often occurred before the movement cue. 3. Bicuculline injections produced irrepressible saccades equivalent to the saccade vector represented by the injection site, often in a staircase of several closely spaced movements. 4. Both substances decreased the accuracy of fixation of a central light. The distribution of points of fixation on different trials was diffuse, and the angle of gaze tended to deviate towards the side of the injection. 5. The results of these acute injections are similiar to those observed in the superior colliculus and are much more substantial than the effects observed in the long term after surgical removal of the frontal eye field. The results of this study promote a central role for the frontal eye field in the generation of all voluntary saccades and in the control of fixation.  相似文献   
7.
We describe a contact printing approach for microarrays that uses fused-silica capillary tubes with tapered tips for printing pins and a pressure/vacuum system to control pin loading, printing, and cleaning. The printing process is insensitive to variable environmental factors such as humidity, and the small diameter of the pins allows routine printing from 1536 well source plates. Pin load capacity, 0.2 microL in the current system, is adjustable by controlling pin length. More than 2000 spots can be printed per 0.2-microL pin load (<100 pl/spot), and densities of >12,000 spots/cm(2) are readily achievable. Solutions with a wide range of viscosities and chemical properties can be printed. The system can print tens of thousands of different solutions at high speed, due to the ability to use large numbers of pins simultaneously, and can produce a large number of replicate arrays since all of the solution picked up by the pins is available for deposition.  相似文献   
8.
The steroid hormone 20-hydroxyecdysone is a key regulatory factor, controlling blood-meal triggered egg maturation in mosquitoes. To elucidate the ecdysone hierarchy governing this event, we cloned and characterized the ecdysone receptor (AaEcR) and the nuclear receptor Ultraspiracle (AaUSP), a retinoid X receptor homologue, from the mosquito, Aedes aegypti, which form a functional complex capable of ligand and DNA binding. Here we analyzed the DNA-binding properties of the AaEcR.AaUSP heterodimer with respect to the effects of nucleotide sequence, orientation, and spacing between half-sites in natural Drosophila and synthetic ecdysone response element (EcREs). By using an electrophoretic gel mobility shift assay, we showed that AaEcR.AaUSP exhibits a broad binding specificity, forming complexes with inverted (IR) and direct (DR) repeats of the nuclear receptor response element half-site consensus sequence AGGTCA separated by spacers of variable length. A single nucleotide spacer was optimal for both imperfect (IRhsp-1) and perfect (IRper-1) inverted repeats; adding or removing 1 base pair in an IRhsp-1 spacer practically abolished binding. However, changing the half-site to the consensus sequence AGGTCA (IRper-1) increased binding of AaEcR.AaUSP 10-fold over IRhsp-1 and, at the same time, reduced the stringency of the spacer length requirement, with IRper-0 to IRper-5 showing detectable binding. Spacer length was less important in DRs of AGGTCA (DR-0 to DR-5); although 4 bp was optimal, DR-3 and DR-5 bound AaEcR.AaUSP almost as efficiently as DR-4. Furthermore, AaEcR. AaUSP also bound DRs separated by 11-13 nucleotide spacers. Competition experiments and direct estimation of binding affinity (Kd) indicated that, given identical consensus half-sites and an optimal spacer, the AaEcR.AaUSP heterodimer bound an IR with higher affinity than a DR. Co-transfection assays utilizing CV-1 cells demonstrated that the mosquito EcR.USP heterodimer is capable of transactivating reporter constructs containing either IR-1 or DR-4. The levels of transactivation are correlated with the respective binding affinities of the response elements (IRper-1 > DR-4 > IRhsp-1). Taken together, these analyses predict broad variability in the EcREs of mosquito ecdysone-responsive genes.  相似文献   
9.
The steroid insect molting hormone 20-hydroxyecdysone is believed to control critical aspects of development and reproduction through a heterodimeric receptor comprising the Ecdysone Receptor and the Ultraspiracle proteins. Recent findings suggest that other hormones and receptors might also be involved.  相似文献   
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