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1.
It seems clear that, for whatever reasons, the dementia of the Alzheimer type patient group (as well as other patient groups) exhibits behavior that is different from the normal control group. G. Storms, T. Dirikx, J. Saerens, S. Verstraeten, and P. P. De Deyn (2003) rightfully argue that the observed behavior (similarity judgments) does not tell us the source (cause) of the differences between the 2 groups. Rather, the focus of the study should be placed more on finding the ways the 2 groups are different. They also point out various methodological problems in some of the previous attempts to characterize the nature of the differences. Further methodological issues in G. Storms et al.'s study are examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
Hwang  Heungsun  Takane  Yoshio 《Behaviormetrika》2005,32(2):155-163

The growth curve model is useful for the analysis of longitudinal data. It helps investigate an overall pattern of change in repeated measurements over time and the effects of time-invariant explanatory variables on the temporal pattern. The traditional growth curve model assumes that the matrix of covariances between repeated measurements is unconstrained. This unconstrained covariance matrix often appears unattractive. In this paper, the generalized estimating equation method is adopted to estimate parameters of the growth curve model. As a result, the proposed method allows a more variety of constrained covariance structures than the traditional growth curve model. An empirical application is provided so as to illustrate the proposed method.

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3.
ABSTRACT: Spicy pollack roe products are a popular seafood item made from fish eggs that should be made with salt-cured mature roes of walleye pollack Theragra chalcogramma . Because of high demand and poor catch of walleye pollack, however, spicy pollack roe products are often susceptible to substitution with roes of closely related codfish. In this study, a simple method identifying the ingredients of commercial spicy pollack roe products was developed to differentiate walleye pollack from codfish substitutes such as gray cod Gadus macrocephalus using PCR-RFLP (Restriction Fragment Length Polymorphism) analysis. PCR amplification of the mitochondrial cytochrome b gene yielded single fragments commonly from pollack and cod. Direct digestion of the PCR products with Mph 11031 restriction enzyme showed an unique restriction fingerprint only in pollack. This PCR-RFLP analysis enabled the reliable identification of commercial spicy pollack roe products made by only pollack roes from products padded with cod roes. It thus can be useful to expose substitution of pollack roes with lower valued codfish roes in commercial spicy pollack roe products.  相似文献   
4.
Thirty-six beagles, 18 months of age, underwent ovariohysterectomy (OHX) or a sham operation. Sham-operated animals were given a diet with standard calcium (1.4%) (group 1, n = 6) or a restricted calcium diet (0.14%) (group 2, n = 6). The OHX animals were given the restricted calcium diet and YH529 orally with respective daily doses of 0, 0.02, 0.1, and 0.5 mg/kg of body weight (groups 3-6, n = 6 each) for 12 months. At the end of this period, the lumbar bone mineral densities (BMDs) in groups 2 and 3 and the load values for group 3 were significantly smaller than those for group 1. The midfemur BMD did not differ among the groups. The urinary deoxypyridinoline (U-Dpy) and bone formation rates (BFR/BS, BFR/BV) in groups 2 and 3 and the osteonal BFR/BS and trabecular osteoclast number (Oc.N/BS) in group 3 were significantly larger than the respective values for group 1. However, these parameters did not significantly differ between groups 2 and 3. The serum osteocalcin (OC) level, wall thickness (W.Th), and mineral apposition rate values for group 3 were significantly larger than those for group 2. In group 2, the trabecular activation frequency (Ac.F) increased by 3.11 times, and the percent values of the number of labeled osteons (L-Ot.N/T-Ot.N, %) in the tibia by 3.28 times over those for group 1. In group 3, the Ac.F increased by 3.20 times and the number of labeled osteons by 3.77 times over those for group 1. In groups 4-6, the U-Dpy and Oc.N/BS values were smaller, but their OC levels did not significantly differ from the level for group 3. The lumbar BMD, the load, and W.Th were dose-dependently significantly larger than those for group 3. The Ac.F values were significantly smaller, and the respective value in groups 4-6 was 67.9, 25.5, and 10.2% of that in group 3. The BMDs of the midfemur in groups 4-6 were significantly larger than those in group 3, but the ultimate load values did not significantly differ. The L-Ot.N/T-Ot.N values were also significantly smaller, and the respective value in groups 4-6 was 82.0, 48.5, and 55.2% of that in group 3. The tibial endocortical and periosteal BFR/BSs did not differ significantly. These data demonstrate that the effects of OHX on bone mass and turnover were small in the beagles fed a restricted calcium diet. YH529 maintained the mass and strength of the lumbar bone by reducing the bone resorption. The cortical bone appeared to be less sensitive to the agent than the trabecular bone in this animal model.  相似文献   
5.
The photopolymerization of vinyl monomers was studied by the system of metal-amine complex and carbon tetrachloride. Addition of amines to the initiating system generally accelerates the polymerization. The acceleration by various sorts of amines in different solvents was examined. It was confirmed that the photopolymerization in question is of free radical character. The polymerization mechanism was discussed.  相似文献   
6.
Brefeldin A (BFA), an isoprenoid fungal metabolite, dramatically disrupts intracellular protein transport and protein secretion. BFA protects cells from the cytotoxicity of a plant toxin, ricin or pseudomonas toxin, but not that of diphtheria toxin (Yoshida et al., 1991. Expt. Cell Res., 192: 389-395.). In this study, we examined whether BFA could differentially change the cytotoxicity of ricin between BFA-sensitive cells and BFA-resistant cells. As a BFA-resistant cell line, we used a resistant cell line, KB/BF2-2, derived from BFA-sensitive human cancer KB cells. BFA treatment caused the disappearance of typical Golgi cisternae and the concomitant appearance of dilated vesicles in the cytoplasm in KB cells. By contrast, KB/BF2-2 cells had already altered Golgi structures with poor development of cisternae and also many vesicles in the absence of BFA, and BFA treatment did not further induce the morphological changes. Although a plasma membrane-specific marker protein, alpha-adaptin, was localized similarly in KB/BF2-2 as KB, Golgi specific markers such as beta-cop and gamma-adaptin were distributed in the cytoplasmic small vesicles as well as Golgi compartments in KB/BF2-2 cells in the absence of BFA, and the mutant cells showed no apparent changes in the distribution even when exposed to BFA. Ricin inhibited protein synthesis in KB and KB/BF2-2 to similar levels while pretreatment of KB cells with BFA at 0.1 microgram/ml almost completely reversed the inhibitory effect of ricin. By contrast, the pre-exposure of KB/BF2-2 cells to 1.0 microgram/ml BFA only partially rescued the ricin-induced inhibition of protein synthesis. Exposure to BFA at 30 min before ricin addition or at 0 min with ricin rescued the protein synthesis inhibition, but no rescue occurred when BFA was added 30 min after ricin addition. BFA could not rescue the protein synthesis inhibition by another toxin, diphtheria toxin. Our results suggest that BFA-resistant mutation causes a specific change in the endocytic membrane traffic of ricin in human cells, and also that cytotoxicity of diphtheria toxin does not share a common pathway of the intracellular transport with that of ricin.  相似文献   
7.
Oleyl and elaidyl alcohol have been stereospecifically hydroxylated by cold, dilute alkaline potassium permanganate toerythro- andthreo-9,10-dihydroxyoctadecanol, respectively, in 40–80% yields in a water-methylene chloride heterogeneous system. Phase transfer agents (PTA) were used to transport permanganate ion from the aqueous to the organic phase. In the absence of PTA, hydroxylation did not take place. Periodic acid cleavage of epoxides in a water-methylene chloride system was studied in the absence and presence of PTA. At slow stirring rates PTA exert a rate accelerating effect in cleaving certain epoxides to aldehydes but with vigorous stirring use of PTA has only a marginal advantage.  相似文献   
8.
Several quaternary ammonium and phosphonium halides have been shown to be useful phase transfer agents (PTA) for the efficient transport of permanganate, periodate, and cyanate ions from aqueous to organic phases (benzene and/or methylene chloride). Chemical and spectral methods of analysis were used to measure ion transfer quantitatively and to assess the relative efficiency of PTA.  相似文献   
9.
The sinus node function was evaluated by rapid atrial pacing in 35 aged patients (mean age 78.2 years) including 10 aged controls, 12 cases with various degrees of AV block, 6 with bradycardia-tachycardia syndrome (BTS), and 7 with sinus bradyarrhythmia (SB). AV block was further divided into A-H block (7 cases) and H-V block (5 cases) by His bundle electrogram which was simultaneously recorded with 3 leads of surface electrocardiogram. Sinus node recovery time (SRT) was measured and its maximum value (SRTmax) was selected from SRTs obtained after pacing with various rates and durations in each patient. SRTmax was also expressed as percentage of the control P-P interval (%SRTmax). For patients in whom the study was repeated 3 to 8 months later, %SRTmax was reproducible in 9 of 14 instances. Prolongation of SRT was not always observed as the rate and/or duration of pacing was increased. SRTmax and %SRTmax were 1,363 +/- 188 msec and 147 +/- 19% (mean +/- SD), respectively, for aged controls, 1,597 +/- 442 msec and 156 +/- 31% for patients with AV block, 2,087 +/- 1,315 msec and 203 +/- 132% for those with BTS, and 3,069 +/- 1,287 msec and 247 +/- 115% for those with SB. SRTmax exceeding the range for aged controls was noted in 4 of 7 cases (57%) with A-H block, 2 of 6 (33%) with BTS, and 5 of 7 (71%) with SB; normal SRT was not infrequently observed in patients with sick sinus syndrome, especially in those with BTS. Analysis of 10 consecutive atrial cycles following cessation of pacing revealed that in 8 cases the first P-P interval (SRT) was followed by longer ones in some occasions (secondary suppression). It was observed almost exclusively in patients with sick sinus syndrome. The possibility of this phenomenon to reflect another feature of sinus node abnormality was discussed.  相似文献   
10.
We investigated the effect of free radical scavengers on the actions of cytokines on islet cells. Interferon-gamma and tumor necrosis factor-alpha reduced the nicotinamide adenine dinucleotide content of mouse islet cells; the combination of interferon-gamma (4 x 10(5) U/l) and tumor necrosis factor-alpha (4 x 10(5) U/l) caused nicotinamide adenine dinucleotide reduction by approximately 40%. Dimethyl urea and dimethyl sulfoxide prevented the decrease, whereas superoxide dismutase, catalase, and mannitol were not effective. Dimethyl urea and dimethyl sulfoxide protected islet cells from the synergistic cytotoxic action of interferon-gamma and tumor necrosis factor-alpha. Major histocompatibility complex class II antigen induction by interferon-gamma and tumor necrosis factor-alpha was also inhibited by dimethyl urea and dimethyl sulfoxide, but not by superoxide dismutase, catalase and mannitol. Since superoxide dismutase of a membrane-penetrable form attenuated the class II antigen induction, the inefficiency of superoxide dismutase, catalase and mannitol may be attributable to their inability to penetrate islet cells. These results suggest that the intracellular generation of free oxygen radicals is involved in islet cell cytotoxicity and class II molecule expression by interferon-gamma and tumor necrosis factor-alpha, and that nicotinamide adenine dinucleotide reduction may be associated with islet cell dysfunction caused by the cytokines.  相似文献   
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