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1.
The thiazolidinedione analogue troglitazone is an antidiabetic agent that improves insulin resistance in rodents and humans. Although coronary artery disease is common in patients with the insulin resistance syndrome, the effects of troglitazone on smooth muscle cells (SMC) have not been fully elucidated. We therefore examined the effects of troglitazone on cell growth and glucose uptake in human aortic SMC. Mitogen-activated protein (MAP) kinase activity and glucose transporter (Glut) 1 mRNA levels were also studied. In the absence of troglitazone, insulin (10(-7) M) caused a 2-fold increase of DNA synthesis in SMC and troglitazone suppressed the increase of DNA synthesis in a dose-dependent manner. This growth suppression was accompanied by inhibition of MAP kinase activity. On the other hand, troglitazone significantly increased Glut 1 mRNA and enhanced glucose uptake in SMC. These results suggest that troglitazone affects the insulin signaling pathways in SMC and suppresses growth while promoting glucose uptake. Our findings support the application of troglitazone as an inhibitor of SMC proliferation in patients with insulin resistance.  相似文献   
2.
Geometric fusion for a hand-held 3D sensor   总被引:2,自引:0,他引:2  
Abstract. This article presents a geometric fusion algorithm developed for the reconstruction of 3D surface models from hand-held sensor data. Hand-held systems allow full 3D movement of the sensor to capture the shape of complex objects. Techniques previously developed for reconstruction from conventional 2.5D range image data cannot be applied to hand-held sensor data. A geometric fusion algorithm is introduced to integrate the measured 3D points from a hand-held sensor into a single continuous surface. The new geometric fusion algorithm is based on the normal-volume representation of a triangle, which enables incremental transformation of an arbitrary mesh into an implicit volumetric field function. This system is demonstrated for reconstruction of surface models from both hand-held sensor data and conventional 2.5D range images. Received: 30 August 1999 / Accepted: 21 January 2000  相似文献   
3.
The molecular mechanisms involved in luteolysis are still unclear in the primate. This study aimed to investigate the effect of induced luteolysis on the ovarian luteinizing hormone (LH) receptor and the steroidogenic enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset monkey. Luteolysis was induced in the mid-luteal phase either directly by systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal using systemic gonadotrophin releasing hormone antagonist (GnRHant) treatment. The LH receptor was studied by isotopic mRNA in-situ hybridization and in-situ ligand binding and 3beta-HSD expression was studied using isotopic mRNA in-situ hybridization and immunohistochemistry. Induced luteolysis was associated with a reduction in the expression of LH receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a reduction in the LH receptor (P < 0.05) and 3beta-HSD protein concentrations within 24 h. There were no differences in the findings whether luteolysis was induced with PGF2alpha or GnRHant. This study shows that disparate mechanisms to induce luteolysis in the primate result in an identical rapid loss of the LH receptor and 3beta-HSD. In conclusion, induced luteolysis leads to rapid loss of the steroidogenic pathway in luteal cells.  相似文献   
4.
A range of commercial processed cheese samples containing starch were prepared on a Rapid Visco Analyser (RVA) and on a pilot plant scale. This work clearly demonstrated that it was possible to manufacture processed cheese with part of the protein replaced with potato starch, while maintaining similar rheological attributes (firmness) to those of the control and an acceptable melt index. Sensory evaluation showed that, although the reduced‐protein cheese samples had a good, clean, fresh flavour that was comparable with that of the control, at high starch concentrations the starch‐containing processed cheese had a pasty texture and tended to stick to the wrapper.  相似文献   
5.
OBJECTIVE: To study the characteristics of birthweight and gestational age of third trimester fetal deaths which occurred before the onset of labour. DESIGN: Review of computerised confidential perinatal mortality records. Data originated from the 1992 Trent Region Perinatal Mortality Survey. SAMPLE: One hundred and forty-nine antepartum stillbirths of at least 24 weeks of gestation confirmed by early ultrasound scan. Congenital abnormalities and multiple pregnancies were excluded. MAIN OUTCOME MEASURES: Reported causes of stillbirth; weight-for-gestational age centiles based on a standard derived from normal pregnancies; pregnancy characteristics compared with the local maternity population. RESULTS: Of 149 stillbirths, 83 (56%) were preterm and 66 were at term, and the majority (126; 85%) occurred from 31 weeks. Most of the deaths (97; 65%) were reported as 'unexplained' even though post-mortems had been carried out in 60% of all cases. Using a gestational age-specific fetal weight standard derived from normal, term live births, 41% of all cases of stillborn infants were small-for-gestational age (< 10th centile; OR 6.2; 95% CI 3.3-11.5); 39% of which had been classified as unexplained were small for gestational age (OR 5.6; 2.6-12.0). This excess of small stillbirths was most pronounced between 31 and 33 weeks, where the weights of 63% of all stillbirths and 72% of unexplained fetal deaths were < 10th centile. Overall, a higher proportion of preterm (< 37 weeks) than term stillbirths were small for gestational age: 53% vs 26% (OR 3.3; 1.6-6.5). However, at term there were also more subtle differences in weight deficit, with more fetuses with a weight between the 10th and 50th centiles than between 50th and 90th (36 vs 11; OR 3.3; 1.4-7.8). Mothers of pregnancies ending in stillbirth were similar in age, size, parity and ethnic group to mothers of live born babies, but were more likely to be smokers (37 vs 27%, OR 1.6; 1.2-2.3). CONCLUSIONS: Many stillborn babies are small for gestational age. In the absence of significant differences in physiological pregnancy characteristics, this is unlikely to be a constitutional smallness, but represents a preponderance of intrauterine growth restriction. For a full appreciation of the strength of this association, appropriate weight standards and classifications need to be applied in perinatal mortality surveys. Many antepartum stillbirths which are currently designated as unexplained may be avoidable if slow fetal growth could be recognised as a warning sign.  相似文献   
6.
Luteolysis is associated with tissue remodeling probably involving the matrix metalloproteinases (MMPs) and their specific tissue inhibitors (TIMPs). This study investigated the expression and localization of the major MMPs and TIMPs in the human corpus luteum throughout the luteal phase and after luteal rescue with hCG. Corpora lutea (n = 9) were collected at hysterectomy and were dated by serial urinary LH estimation. In addition, corpora lutea (n = 3) were collected from women who had received daily doubling doses of hCG to mimic the hormonal changes of early pregnancy. MMP-1, MMP-2, MMP-9, TIMP-1, TIMP-2, and TIMP-3 were investigated by zymography, reverse zymography, Northern blotting, and in situ hybridization. There was no change in the expression of MMP-1, TIMP-1, and TIMP-2 throughout the luteal phase or after luteal rescue. Little TIMP-3 could be detected in the corpus luteum. MMP-9 activity peaked in the early and late luteal phase. The expression and activity of MMP-2 were maximal in the late luteal phase. Exposure to hCG during luteal rescue in vivo was associated with a reduction (P < 0.05) in the expression and activity of MMP-2. Messenger ribonucleic acids (mRNAs) for MMP-1, MMP-2, and TIMP-2 were localized to the connective tissue stroma and the thecal-lutein cells of the corpus luteum. In contrast, TIMP-1 mRNA was localized to the granulosa-lutein cells, and MMP-9 mRNA was expressed in scattered cells within the steroidogenic and nonsteroidogenic cell layers. In conclusion, during maternal recognition of pregnancy, hCG prevents the normal increase in MMP-2 in the late luteal phase. MMPs can function in an environment containing large amounts of TIMP-1, as they have a different cellular localization.  相似文献   
7.
Temozolomide, a new oral cytotoxic agent, was given to 75 patients with malignant gliomas. The schedule used was for the first course 150 mg/m2 per day for 5 days (i.e. total dose 750 mg/m2), escalating, if no significant myelosuppression was noted on day 22, to 200 mg/m2 per day for 5 days (i.e. total dose 1000 mg/m2) for subsequent courses at 4-week intervals. There were 27 patients with primary disease treated with two courses of temozolomide prior to their radiotherapy and 8 (30%) fulfilled the criteria for an objective response. There were 48 patients whose disease recurred after their initial surgery and radiotherapy and 12 (25%) fulfilled the criteria for an objective response. This gave an overall objective response rate of 20 (27%) out of 75 patients. Temozolomide was generally well tolerated, with little subjective toxicity and predictable myelosuppression. However, the responses induced with this schedule were of short duration and had relatively little impact on overall survival. In conclusion, temozolomide given in this schedule has activity against high grade glioma. However, studies evaluating chemotherapy in primary brain tumours should include a quality-of-life/performance status evaluation in addition to CT or MRI scanning assessment.  相似文献   
8.
9.
Two studies investigated the hypothesis that individuals using the cognitive strategy of defensive pessimism will perform better and feel better when allowed to play through possible outcomes and reflect on their progress. In contrast, individuals using an optimistic strategy will perform more poorly and feel worse when they are encouraged or required to reflect on themselves and their goals. A laboratory experiment and a study using experience-sampling methodology (ESM) revealed this pattern for self-reported mood, appraisal of tasks, and progress toward goals; objective performance; and a physiological measure, though the interaction was not always statistically significant. Discussion focuses on the probable content of reflective thought for these individuals, the relative costs and benefits of each approach, and the usefulness of a strategy-oriented approach to the study of individual differences and self-regulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
In recent years, a number of surveys have indicated a significant escalation in reported incidents of computer crime and abuse. This rise is coupled with increasing attention to the issue in the mass media, which has the effect of heightening public perceptions of problems with IT and may represent a barrier to the adoption of technologies such as the Internet and World Wide Web.This paper considers the effects of computer crime and draws upon the results of a survey conducted to assess public attitudes and awareness of the issue. With the mass media playing an important role in shaping individual opinions, this survey considered the effect that the reporting of incidents has upon public perceptions and understanding of computer crime and abuse.The survey results show that individual awareness of computer crime and abuse is high and that the majority of respondents perceive it to be a problem. However, the views expressed regarding the seriousness of the different types of abuse (and the potential motivations for them) were more variable. In addition, awareness of abuse is more widespread than knowledge of the associated legislation that may be used to prevent and punish it. The results also revealed the significant potential for media reports to influence opinions in this area, highlighting the importance of a responsible attitude in order to foster the information society.  相似文献   
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