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61.
Technological progress in an industry is enabled by the collective R&D efforts of suppliers, users and research organizations. In this study, we explore how the pattern of R&D collaboration within the industry community evolves over the technology life cycle. We propose that as the technology evolves from an initial emergence stage to subsequent stages of growth and maturity, there is a corresponding change in the opportunities and challenges confronting industry participants. This results in a shift not only in the relative propensities for internal and collaborative R&D, but also in the distribution of the different types of collaborative interactions involving research organizations, suppliers and users. The context for the study is the global semiconductor manufacturing industry from 1990 to 2010. During this period, the industry experienced exponential technological progress that was fueled by the deep ultraviolet (DUV) manufacturing technology. We draw upon a comprehensive archival dataset of more than 12,000 articles presented in industry technical conferences to analyze the pattern of collaborative R&D during the emergence, growth and maturity stages of the DUV technology. The observed trends in the semiconductor manufacturing industry point to intriguing shifts in the efforts and interactions among suppliers, users and research organizations as they collectively push the technology envelope forward.  相似文献   
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63.
Study on Relation of Metabolic Syndrome with Menopause   总被引:1,自引:0,他引:1  
This study is carried out to determine the prevalence of metabolic syndrome (MS) in 148 women between 36 to 65 years using the International Diabetes Federation criteria in the North-Eastern part of India. The prevalence of MS and all its individual components were found to be significantly higher among postmenopausal as compared to premenopausal and perimenopausal women. Various components of MS except waist circumference shows a significant increase and homeostasis model assessment index for insulin resistance also showed significant differences between the three groups. All the MS diagnostic markers (except serum high density lipoprotein) showed a strong positive correlation with MS score among the groups. Further MS score correlated with indicators of insulin resistance evaluated. This study concluded that MS is highly prevalent among North-East Indian postmenopausal women seeking primary health care and its determinant factors related to age and sedentary habits. Thus recognizing and treating MS early with proper intervention can minimize complication.  相似文献   
64.
Double volume (170 ml/kg body weight) exchange transfusion was done in 52 term infants in the first week of life for neonatal hyperbilirubinemia. The M:F ratio was 1.08:1 and 37 (71.1%) babies were of low birth weight. Causes of jaundice were hemolytic in 46.2% and non-hemolytic in 41.3% cases; in 13.5% babies no cause of jaundice could be found. After exchange transfusion a fall of 14.6% and 47.4% was observed in the hemoglobin and serum bilirubin levels respectively. There was significant (p=0.0414) rise in the mean mid exchange and post-exchange serum sodium levels as compared to pre-exchange values and it was found to be due to higher donor's serum sodium levels (p=0.007). There was no effect on the serum potassium levels during or after ET. In general serum calcium levels significantly increased at mid-exchange period (p=0.0029) but post-exchange levels were same as pre-exchange. Donor's serum calcium level had no effect on the infant's serum calcium level (p=0.993). There was no change in the serum phosphate and blood urea levels during and after exchange-transfusion. The plasma glucose was significantly raised during and after ET and plasma glucose of the donors had significant effect on the infant's plasma glucose levels (p=0.043). Similarly plasma osmolality also showed significant increase during and after ET which was due to the effect of donor's plasma osmolality (p=0.007).  相似文献   
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66.
This study tested the veracity of a model of Mathematics Anxiety as the end-point of related self-regulatory and self-efficacy processes. Data were collected in India from 232, eighth grade students on the Motivated Strategies for Learning Questionnaire and the Mathematics Anxiety Scale. Demographic information such as student’s gender, age, marks scored in last mathematics exam and occupation of both parents was also collected. The measures in the study were tested to ascertain their psychometric properties, including any effect that gender had on these properties. A Structural Equation Model of Mathematics Anxiety was then constructed and evaluated based in the measures tested in the related measurement models.  相似文献   
67.
Heat stable fraction (HSF) of alkaline phosphatase (ALP) was evaluated as an adjunct to CA 125 as a tumour marker for epithelial ovarian cancer in a follow-up study. In our study group 63.4% of patients had elevated HSF levels (≥10U/L) and 93.3% had elevated CA 125 levels (>35U/mL). The sensitivity of CA 125 and HSF was 93.3% and 63.3% respectively. The decline in the activity of HSF, over the pre-op levels was highly significant after the first (p=0.001) chemotherapy cycle and significant after the second and third cycles (p<0.029). Thereafter, HSF activity was almost undetectable. The decrease in CA 125 levels over the pre-op levels was significant after the first, second, third (p<0.001) and fourth (p<0.034) chemotherapy cycle. HSF can be used alone or as an adjunct to CA 125 in screening and monitoring patients of ovarian carcinoma especially in remote areas where sophisticated facilities are not available and in patients in which CA 125 levels are not raised preoperatively.  相似文献   
68.
Extensive data from animal and human studies indicate a role of vitamin D in erythropoiesis. Iron and vitamin D deficiencies are implicated with adverse health effects in children even if they are asymptomatic. The potential relationship between the two remains poorly understood. A cross-sectional study was performed in the period from 1st May 2012 through 30th April 2013 and subjects were classified into vitamin D deficiency (VDD), vitamin D insufficiency (VDI) and vitamin D sufficiency (VDS) groups according to their 25(OH) D levels. A total of 263 children were included in the analysis. Anaemia was present in 66 % of 25(OH) D deficient subjects compared with 35 % in vitamin D sufficient individuals (p < 0.0001). The association of breast feeding and development of VDD was also significant (p < 0.05). Serum levels of 25(OH) D were found lower in female sex and if the analysis was performed in the winter/spring season. Physicians should therefore assess vitamin D levels in all anaemic children and ensure adequate supplementation to prevent deficiencies.  相似文献   
69.
Cataract is one of the leading causes of visual disability often leading to blindness in the elderly population. One of the causes is oxidation of proteins present in lens, by hydrogen peroxide (H2O2). In the present study 100 goat lenses were analyzed to determine the protective efficacy of ketoacids, against the oxidative insult by H2O2. The ketoacids used were (pyruvate, alpha ketoglutarate and oxaloacetate), that are constantly produced endogenously. The lenses were incubated as control and experimental groups in TC-199 media for 72 hrs. H2O2 concentration of 10mM was used to induce cataract. The biochemical parameters measured were levels of malondialdehyde (MDA), a lipid peroxidation product and activity of glutathione peroxidase (G-Px), an enzymatic antioxidant. The results showed a significant increase in the levels of MDA and significant decrease in the activity of G-Px in the cataractous lenses as compared to control. After addition of ketoacids (pyruvate (10mM), alpha ketoglutarate (20mM) and oxaloacetate (20mM)) separately, the levels of MDA decreased significantly and the activity of G-Px increased significantly. The results suggest that the ketoacids can be very promising antioxidants for the treatment of cataract. They may also be useful in treating other disabilities related to acute and chronic oxidative stress.  相似文献   
70.
Immune dysregulation in COVID-19 is the major causal factor associated with disease progression and mortality. Role of monocyte HLA-DR (mHLA-DR), neutrophil CD64 (nCD64) and Immune dysregulation index (IDI) were studied in COVID-19 patients for assessing severity and outcome. Results were compared with other laboratory parameters. Antibody bound per cell for mHLA-DR, nCD64 and IDI were measured in 100 COVID-19 patients by flow cytometry within 12 h of hospital admission. Thirty healthy controls (HC) were included. Clinical and laboratory parameters like C - reactive protein (CRP), Procalcitonin (PCT), Absolute Lymphocyte count (ALC), Absolute Neutrophil count (ANC) and Neutrophil to Lymphocyte ratio (NLR) were recorded. Patients were followed up until recovery with discharge or death. Parameters from 54 mild (MCOV-19), 46 severe (SCOV-19) and 30 HC were analysed. mHLA-DR revealed significant and graded down regulation in MCOV-19 and SCOV-19 as compared to HC whereas IDI was lowest in HC with increasing values in MCOV-19 and SCOV-19. For diagnostic discrimination of MCOV-19 and SCOV-19, IDI revealed highest AUC (0.99). All three immune parameters revealed significant difference between survivors (n = 78) and non-survivors (n = 22). mHLA-DR < 7010 and IDI > 12 had significant association with mortality. Four best performing parameters to identify patients with SCOV-19 at higher risk of mortality were IDI, NLR, ALC and PCT. mHLA-DR and IDI, in addition to NLR and ALC at admission and during hospital stay can be utilized for patient triaging, monitoring, early intervention, and mortality prediction. IDI reported for the first time in this study, appears most promising. Immune monitoring of ‘in hospital’ cases may provide optimized treatment options.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12291-022-01087-z.  相似文献   
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