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1.
For the present purpose, love is defined as one's having stimulation that one desires. The nature of the stimulation can range on a continuum from the most abstract cognitive, to the most direct sensory, forms. Thus, this definition of love encompasses having an emotional bond with a person for whom one yearns, as well as having sensory stimulation that one desires. We address some of the physiological and perceptual consequences both of having, and of not having, love. We propose a neural mechanism by which deprivation of love may generate endogenous, compensatory sensory stimulation that manifests itself as psychosomatic illness. In addition, we propose a neuroendocrine mechanism underlying sexual response and orgasm. The latter includes vaginocervical sensory pathways to the brain that can produce analgesia, release oxytocin, and/or bypass the spinal cord via the vagus nerve. We present evidence of the existence of non-genital orgasms, which suggests that genital orgasm is a special case of a more pervasive orgasmic process. Through recent studies, the mechanisms and manifestations of love and its deprivation are becoming better understood. The better is our understanding of love, the greater is our respect for the significance and potency of its role in mental and physical health.  相似文献   
2.
The objective of this study was to determine the effect of 30 mM CaCl(2) on the solubilization of those structural proteins that contribute to myofibril stability. Ovine M. longissimus dorsi (longissimus) samples were obtained immediately post-exsanguination, myofibrils were isolated, glycerated, and frozen until needed. Myofibrils were washed, diluted and incubated in 0·1 m KCl, 10 mm Tris, pH 7·0 buffer for 24, 48 and 72 h. Treatments consisted of: (1) control, (2) 1 mm E(64), (3) 30 mm CaCl(2), and (4) 1 mm E(64) + 30 mm CaCl(2). Results (SDS-PAGE) indicated that myosin heavy chain (though not to a great extent), M-protein, C-protein, α-actinin, actin, troponin-T, tropomyosin isoforms, troponin-I and 72, 70, 62, 33, 32, 30, and 22 kDa unidentified bands were solubilized from myofibrils incubated in KCl buffer for 72 h. The addition of CaCl(2) hastened the appearance of some of the proteins in the supernatant fractions, but no differences were observed at 72 h among the treatments. The addition of E(64) had no effect on which proteins were released. Thus, in the absence of proteolysis it appears that a general solubilization of thick-and-thin filament ancillary proteins occurs in the presence of 30 mm CaCl(2). However, the contribution to tenderness should be minimal, because solubilized proteins are not part of the cytoskeletal elements that are responsible for maintaining structural integrity of the tissue.  相似文献   
3.
[Correction Notice: An erratum for this article was reported in Vol 36(3) of Journal of Experimental Psychology: Human Perception and Performance (see record 2010-10162-008). A key reference for coauthor Gregory T. Stevens’s PhD dissertation was omitted and appears in the correction.] The effects of Simon- and Stroop-like stimuli are examined in isolation and in factorial combinations with different delays between the presentation of the irrelevant and the relevant stimuli. The effects of irrelevant stimuli have different time courses depending on whether they overlap with the relevant stimulus (stimulus-stimulus overlap, Dimensional Overlap [DO] Type 4) or with the response (stimulus-response overlap, DO Type 3). A new, computational, parallel distributed processing (PDP)-type model, DO'97, is presented that is based on the original DO model (S. Kornblum, 1994; S. Kornblum, T. Hasbroucq, & A. Osman, 1990), and it postulates a nonmonotone irrelevant stimulus activation function in addition to 2 temporally ordered, serial, nonindependent stages: a stimulus processing stage and a response production stage. DO'97 is able to simulate the temporal dynamic characteristics of the processes, with good fits to the empirical data of this study and other published studies, at the level of means, variances, and distributional plots. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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5.
Analysis of mitochondrial (mt)DNA size polymorphism in the form of variable number tandem repeats (mtVNTRs) has become an increasingly popular methodology for addressing questions in molecular ecology. When detected by PCR, mtVNTR analysis can provide a sensitive, rapid, and cost-effective measure of genetic variability that may be exploited in studies of population differentiation and biogeography. Despite the emergence of this approach, there has been little critical evaluation of its success or utility as a practical tool. In this review, we identify problematic methodological, theoretical and interpretive factors that can influence the utility of mtVNTR analysis. The reliability of the procedure is considered in terms of both detection of alleles and scoring of intra-individual allele frequencies. While many of the potential technical problems of the technique do not raise serious practical concerns, this rapid and sensitive methodology is seriously compromised by the difficulty of reliably assessing allele frequencies, of assaying only germline tissue, and in our ignorance of the mechanisms generating mtVNTR diversity. Thus, although there is a considerable potential for mtVNTR pilot studies to assess genetic diversity, the utility of the technique to resolve broader questions in molecular ecology should be treated cautiously until such a time as the system is better understood.  相似文献   
6.
We have designed and demonstrated a standoff Raman system for detecting high explosive materials at distances up to 50 meters in ambient light conditions. In the system, light is collected using an 8-in. Schmidt-Cassegrain telescope fiber-coupled to an f/1.8 spectrograph with a gated intensified charge-coupled device (ICCD) detector. A frequency-doubled Nd : YAG (532 nm) pulsed (10 Hz) laser is used as the excitation source for measuring remote spectra of samples containing up to 8% explosive materials. The explosives RDX, TNT, and PETN as well as nitrate- and chlorate-containing materials were used to evaluate the performance of the system with samples placed at distances of 27 and 50 meters. Laser power studies were performed to determine the effects of laser heating and photodegradation on the samples. Raman signal levels were found to increase linearly with increasing laser energy up to approximately 3 x 10(6) W/cm2 for all samples except TNT, which showed some evidence of photo- or thermal degradation at higher laser power densities. Detector gate width studies showed that Raman spectra could be acquired in high levels of ambient light using a 10 microsecond gate width.  相似文献   
7.
Vitamin A was destroyed in cod liver oil as rancidity developed. Vitamin A was destroyed at lower peroxide values when rancidity developed at room temperature than when it was accelerated by aeration at 100°C. It is suggested that not only vitamin A, but other biological properties of oils are not equally affected by rancidity produced in different ways and at different rates, and that peroxide value may not necessarily be parallel to that of other changes which take place in an oil as rancidity develops.  相似文献   
8.
The aim of this study was to examine the developmental significance of the newly developed dimensional approach to attachment state of mind by investigating its capacity to predict individual differences in the quality of two caregiving behaviors—maternal sensitivity and maternal autonomy support—that are linked to numerous important child outcomes. Seventy-one upper-middle-class, predominantly French-speaking and Caucasian dyads participated in 3 home visits (34 girls). The Adult Attachment Interview (AAI) was administered when the infants were 8 months old, maternal sensitivity was assessed when they were 12 months old, and maternal autonomy support was assessed at 15 months. The results revealed that, above and beyond SES, maternal sensitivity was negatively related to the dismissing dimension of the AAI, whereas maternal autonomy support was negatively linked to the preoccupied/unresolved dimension. In contrast, the traditional AAI categories were not significantly linked to parenting. These results speak to the relevance of using a continuous approach to attachment state of mind when predicting individual differences in specific caregiving behaviors. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
9.
Understanding the intergenerational transmission of attachment patterns has been a main focus of attachment research for many years. Most of the empirical work conducted on this question has addressed maternal sensitivity to infants’ attachment needs. Given that security of attachment is defined as an attachment/exploration balance, some researchers have stressed the need to explore maternal behaviours in the context of infant exploration. The authors propose that self-determination theory (SDT) could contribute to attachment work in this respect given that it has clearly operationalized parental exploration-related behaviours and has related them to numerous child outcomes. This article highlights conceptual, empirical, and methodological parallels that can be drawn between SDT and attachment theory, thus suggesting that they could be complementary on many levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
c-myc gene abnormalities associated with lymphomagenesis, including rearrangements and mutations in the regulatory region between exon I and intron I, have been studied in 54 MALT lymphomas (43 low and 11 high grade) and 36 nodal lymphomas (27 low and 9 high grade). By Southern blot analysis, none of the 54 MALT lymphomas but 2 of 36 nodal lymphomas had c-myc gene rearrangements. Defined tumour cell populations from all MALT lymphoma cases were isolated by microdissection from frozen tissue sections and analysed by polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP) and direct sequencing for somatic mutations in the exon I/intron I region of the gene. Point mutations in this region were identified in nine cases of MALT lymphomas (7/43 = 16.2 per cent of low grade; 2/11 = 18.1 per cent of high grade). These mutations were located at either the exon I/intron I border of myc intron factor (MIF) binding sites, which are critical in the negative regulation of c-myc expression. Of the nodal lymphomas, only the two cases (5-6 per cent) with c-myc gene rearrangement showed scattered or clustered mutations. These results suggest that c-myc mutations in MALT lymphomas are unlikely to be associated with chromosome translocation, which is the main cause of somatic mutations observed in other types of lymphomas. The mutations involving the c-myc regulatory regions may play a pathogenetic role in at least a proportion of MALT lymphomas.  相似文献   
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