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201.
Research into the genetics of migraine remains difficult because of the involvement of polygenetic and environmental factors. The discovery of the gene for familial hemiplegic migraine on chromosome 19p 13 is an important step forward. This brain specific P/Q-type calcium channel alpha 1-subunit gene opens new avenues for studying the genetics of migraine, the pathophysiology of the onset of migraine attacks and the development of novel specific prophylactic drugs. 相似文献
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203.
OBJECTIVES: To investigate the influence of progesterone on proliferation and differentiation of osteoblast at the levels of gene expression and cell functions. METHODS: Fetal rat calvarial osteoblasts were cultured in vitro in the presence of (10(-9) mol/L-10(-6) mol/L) progesterone. Cell proliferation, alkaline phosphalase (ALP) activity, osteocalcin mRNA expression and osteocalcin secretion in the medium and bone nodule formation were analyzed. RESULTS: Progesterone did not influence cell proliferation; Progesterone enhanced the ALP activity in rat osteoblasts; Progesterone stimulated osteocalcin mRNA expression in a dose-dependent manner and increased the amount of osteocalcin in the culture medium; Progesterone increased both number and area of bone nodule formation. CONCLUSION: Progesterone has a multi-stimulating effect on the differentiation of fetal rat calvarial osteoblast, hut no effect on cell proliferation. 相似文献
204.
We examined the effect of dietary n-6 and n-3 fatty acids on the lipid composition and physical properties of erythrocyte membranes together with cholesterol and triglyceride plasmatic levels in normal and experimental diabetic rats. Plasmatic total cholesterol and triglyceride did not change in normal rats under the dietary regime, but both parameters decreased significantly in the diabetic animals after the consumption of either n-6 or n-3 fatty acids. Lipid analyses of erythrocyte membranes revealed a significant decrease in the total cholesterol together with an increase in the phospholipid amount in the diabetics compared to the normal rats. As a consequence, cholesterol/phospholipid ratio decreased in these groups of animals and markedly in those fed n-3 fatty acids. These changes would be responsible for the lower fluorescent polarization of DPH observed in the latter group. We conclude that equivalent and adequate amounts of dietary either n-6 or n-3 fatty acids produce plasmatic and red cell membrane lipid changes in diabetic rats that may improve the evolution of the disease. 相似文献
205.
Johannes Burtscher Grgoire P. Millet Nicolas Place Bengt Kayser Nadge Zanou 《International journal of molecular sciences》2021,22(12)
Regular exercise is associated with pronounced health benefits. The molecular processes involved in physiological adaptations to exercise are best understood in skeletal muscle. Enhanced mitochondrial functions in muscle are central to exercise-induced adaptations. However, regular exercise also benefits the brain and is a major protective factor against neurodegenerative diseases, such as the most common age-related form of dementia, Alzheimer’s disease, or the most common neurodegenerative motor disorder, Parkinson’s disease. While there is evidence that exercise induces signalling from skeletal muscle to the brain, the mechanistic understanding of the crosstalk along the muscle–brain axis is incompletely understood. Mitochondria in both organs, however, seem to be central players. Here, we provide an overview on the central role of mitochondria in exercise-induced communication routes from muscle to the brain. These routes include circulating factors, such as myokines, the release of which often depends on mitochondria, and possibly direct mitochondrial transfer. On this basis, we examine the reported effects of different modes of exercise on mitochondrial features and highlight their expected benefits with regard to neurodegeneration prevention or mitigation. In addition, knowledge gaps in our current understanding related to the muscle–brain axis in neurodegenerative diseases are outlined. 相似文献
206.
Wolfe Jeremy M.; Horowitz Todd S.; Van Wert Michael J.; Kenner Naomi M.; Place Skyler S.; Kibbi Nour 《Canadian Metallurgical Quarterly》2007,136(4):623
In visual search tasks, observers look for targets in displays containing distractors. Likelihood that targets will be missed varies with target prevalence, the frequency with which targets are presented across trials. Miss error rates are much higher at low target prevalence (1%-2%) than at high prevalence (50%). Unfortunately, low prevalence is characteristic of important search tasks such as airport security and medical screening where miss errors are dangerous. A series of experiments show this prevalence effect is very robust. In signal detection terms, the prevalence effect can be explained as a criterion shift and not a change in sensitivity. Several efforts to induce observers to adopt a better criterion fail. However, a regime of brief retraining periods with high prevalence and full feedback allows observers to hold a good criterion during periods of low prevalence with no feedback. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
207.
AM Camoratto JP Jani TS Angeles AC Maroney CY Sanders C Murakata NT Neff JL Vaught JT Isaacs CA Dionne 《Canadian Metallurgical Quarterly》1997,72(4):673-679
The present report describes the in vitro and in vivo profile of CEP-751, a novel receptor tyrosine kinase inhibitor. CEP-751 at 100 nM inhibits the receptor tyrosine kinase activity of the neurotrophin receptors trkA, trkB and trkC. CEP-751 has no effect on activity of receptors for EGF, IGF-I, insulin or on erbB2; inhibition of receptors for PDGF and bFGF was observed but occurred with lesser potency than inhibition of trk. CEP-751 exhibited anti-tumor efficacy against tumors derived from NIH3T3 cells transfected with trkA. Inhibition of trk phosphorylation could also be measured in these tumors, suggesting that anti-tumor efficacy of CEP-751 is related to inhibition of trk receptor tyrosine kinase activity. CEP-751 was found to be without effect when administered to nude mice bearing SK-OV-3 tumors, which overexpress erbB2 receptors, providing further evidence that inhibition of tumor growth may be related to inhibition of trk receptor tyrosine kinase activity. Our data indicate that CEP-751 is a potent trk inhibitor which possesses anti-tumor activity. 相似文献
208.
209.
SC Mishoe RR Baker S Poole LM Harrell CB Arant NT Rupp 《Canadian Metallurgical Quarterly》1998,35(7):553-563
The purpose of this study was to develop and evaluate a new instrument, About My Asthma (AMA), to assess stressors affecting quality of life in children with asthma. The AMA is a 55-item, 4-point Likert-type scale. Concurrent validity was established by comparing the AMA with the Pediatric Asthma Quality of Life Questionnaire (PAQLQ). Increased levels of stress measured by the AMA correlated with a decreased quality of life measured by the PAQLQ. We conclude that the AMA is a valid and reliable instrument to measure the quantity and type of stressors experienced by children who have asthma. 相似文献
210.
BACKGROUND: Orthotopic heart transplantation is currently a widely accepted treatment for end-stage heart disease. Early detection and adequate therapy of acute rejection increases the survival rate. Currently, the most reliable technique for the detection of acute cardiac rejection (ACR) is endomyocardial biopsy (EMB), which is an invasive procedure with some intrinsic problems. The purpose of this study was to assess heart rate variability (HRV) as a noninvasive procedure for frequent monitoring of ACR. METHODS: Six consecutive orthotopic cardiac transplant recipients were prospectively recruited into this study. The follow-up periods ranged from seven to 359 days (median; 146 days). A precordial electrocardiograph (ECG) of 288 seconds was recorded at 5:00 PM before the patient underwent EMB. The results from the frequency domain analysis of the ECG signals were evaluated to correlate with the findings from EMB. RESULTS: Of 48 EMBs, 42 (87.5%) showed no evidence of rejection, four showed mild focal ACR (EMB grade 1A), one mild diffuse ACR (1B) and one moderate plurifocal ACR (3A). There was no moderate focal ACR (2), severe diffuse ACR (3B) or severe ACR (4). Correlation between ACR (3A) and a significant increase in HRV with a corresponding 'broad-band' or bell-shaped pattern on the power spectrum was noted. CONCLUSIONS: Our study in consecutive cardiac transplant recipients indicates that the changes in HRV provide clinicians with a new concept for heart transplant monitoring. Further study is needed to verify clinical utility. 相似文献