全文获取类型
收费全文 | 214篇 |
免费 | 0篇 |
专业分类
化学工业 | 6篇 |
机械仪表 | 1篇 |
无线电 | 4篇 |
一般工业技术 | 16篇 |
冶金工业 | 170篇 |
自动化技术 | 17篇 |
出版年
2023年 | 1篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2016年 | 1篇 |
2014年 | 2篇 |
2013年 | 7篇 |
2012年 | 1篇 |
2011年 | 1篇 |
2010年 | 2篇 |
2009年 | 3篇 |
2008年 | 5篇 |
2007年 | 5篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 3篇 |
1999年 | 7篇 |
1998年 | 43篇 |
1997年 | 30篇 |
1996年 | 18篇 |
1995年 | 9篇 |
1994年 | 10篇 |
1993年 | 11篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1986年 | 2篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1978年 | 2篇 |
1977年 | 7篇 |
1976年 | 23篇 |
1975年 | 3篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1955年 | 1篇 |
1945年 | 1篇 |
排序方式: 共有214条查询结果,搜索用时 15 毫秒
91.
VJ Higgins M Braidwood P Bell P Bissinger IW Dawes PV Attfield 《Canadian Metallurgical Quarterly》1999,65(2):680-685
92.
IW Booth 《Canadian Metallurgical Quarterly》1993,341(8851):996-997
Gastroenteritis in children is usually treated with the graded introduction of milk feeds after rehydration. Although having never been rigorously tested, the practice of gradually increasing milk strength over several days has been considered an appropriate means of warding against lactose intolerance and preventing sensitization to cow's milk antigens. These guidelines were formulated in Europe and North America and invariably lead to a reduction in nutrient intake. Malnourished children in developing countries, however, may experience an average 5-6 episodes of acute diarrhea per year and the nutrient effects are cumulative. A recent study from Latin America explored whether continued feeding is safe for infants under age 6 months and whether malnourished children respond adversely. Infants randomly assigned to receive full strength cow's milk immediately after rehydration did not have more treatment failures, higher stool outputs, or longer lasting diarrhea than those whose feeds were regarded to full strength over 48 hours. It is unclear, however, whether the youngest or more malnourished subjects were overrepresented in the treatment failures. Results also indicate that deciding to change treatment should not be dictated by the presence of reducing substances in the faeces; the majority of infants with reducing substances in their stools did well. This study offers the first scientific support for rapidly reintroducing full-strength milk formula after gastroenteritis is malnourished patients under 6 months of age. The 10% of infants in which dehydration recurs after reintroducing milk feeds are still difficult to manage. In the absence of yogurt or lactose-free formula, a locally-produced modular feed of chicken, starch, and vegetable oil may be suitable. 相似文献
93.
EP McCoy VR Maddineni P Elliott RK Mirakhur IW Carson RA Cooper 《Canadian Metallurgical Quarterly》1993,40(8):703-708
Haemodynamic variables were measured following administration of rocuronium 0.6 mg.kg-1 or vecuronium 0.08 mg.kg-1 (approximately equivalent to 2 x ED95 doses) in patients anaesthetized with fentanyl 50 micrograms.kg-1 and scheduled to undergo elective coronary artery bypass grafting. There were increases in stroke volume index (+15%) and cardiac index (+11%), and a decrease in pulmonary capillary wedge pressure (-25%) following administration of rocuronium (P < 0.05). The changes in heart rate (+7%), mean arterial pressure (-5%), systemic vascular resistance (-12%) and other measured or derived indices were insignificant. In comparison the administration of vecuronium was associated with decreases in heart rate (-7%), mean pulmonary artery pressure (-17%), central venous pressure (-15%) and the rate-pressure product (-9%) (P < 0.05). The changes in mean arterial pressure (-7%), cardiac index (-6%) and systemic vascular resistance (-8%) following vecuronium were insignificant. There were no differences in any of the variables between rocuronium and vecuronium. The absolute values of all variables were, however, within acceptable clinical limits. There was no evidence of histamine release in any patient. The present study shows that rocuronium 0.6 mg.kg-1 is associated with changes of only small magnitude in haemodynamic variables. 相似文献
94.
Membranes from a HEK-293 cell line expressing the beta(2)-adrenergic receptor (beta(2)-AR) have been immobilized on an artificial membrane liquid chromatographic stationary phase. The resulting phase was packed into a glass column (1.8 x 0.5 (i.d.) cm) and used in on-line chromatographic system. Frontal displacement affinity chromatography was used to determine the dissociation constants (K(d)) of CGP 12177A (552.6 nM) and (S)-propranolol (84.3 nM). Zonal displacement chromatography using CGP 12177A as the marker and racemic mixtures of the antagonists nadolol and propranolol demonstrated that the immobilized beta(2)-AR retained its ability to specifically bind these compounds. Similar experiments with (R)- and (S)-propranolol demonstrated that the immobilized receptor retained its enantioselectivity as (S)-propranolol displaced the CGP 12177 marker to a great extent that the (R)-enantiomer. The addition of the agonist butoxamine to the mobile phase increased the retention of the CGP-12177A as did the addition of the agonist fenoterol. These results indicate that the immobilized beta(2)-AR retained its ability to undergo ligand-induced conformational changes. The data from this study suggest that the immobilized beta(2)-AR can be used to screen for ligand binding interactions in both the resting and active states of the receptor. 相似文献
95.
The performance of minority examinees on the SAT is carefully monitored by the national educational media. Changes of 10 or 15 points over a five-year period are interpreted as having a significant and important relationship to the educational process. A crucial assumption underlying the validity of this inference is that the performance of an examinee is unrelated to that examinee's choosing to identify his or her ethnicity. In this article, it is shown that this assumption is false and that the potential errors introduced by it dwarf the changes being interpreted as real. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
97.
98.
AP Freeman KR Fatches IW Carter MJ Cloonan DE Wilcken 《Canadian Metallurgical Quarterly》1981,45(4):389-392
We compared the clinical usefulness of serum myoglobin and creatine kinase MB (CK MB) isoenzyme determinations in the early diagnosis of acute myocardial infarction in 109 consecutive patients admitted to a coronary care unit. Of these, 37 patients were diagnosed as having definite infarction, three possible infarction, and 69 no infarction, using World Heath Organisation criteria. Blood samples were taken on admission and two to four hours later, Both CK MB and myoglobin were raised in the initial serum samples in 24 of the 37 patients with definite infarction. In an additional seven patients both CK MB and myoglobin were negative in the first specimen though both were detected in the second sample. In five patients CK MB preceded the appearance of myoglobin while in the remaining patient myoglobin appeared before CK MB. We conclude that the detection of serum myoglobin does not offer any clinical advantage over CK MG as an early indicator of myocardial infarction. 相似文献
99.
L Rabeneck PM Hartigan IW Huang J Souchek NP Wray 《Canadian Metallurgical Quarterly》1997,50(11):1231-1240
This article (Part II) and the preceding article (Part I) report the development of two clinical staging systems for HIV-infected individuals. The objective of the research reported here (Part II) was to construct a clinical staging system to predict survival in patients with AIDS. We analyzed data from VA Cooperative Study Number 298, a multicenter, double-blind, randomized trial that compared immediate versus deferred zidovudine therapy in HIV-infected individuals. Baseline variables obtained at the onset of AIDS in 204 individuals were tested in univariate Cox regression for their relationship to survival, and those that appeared predictive were examined in multivariable analysis. Based on these analyses, we constructed a new AIDS Clinical Staging System. The system is based on age, CD4+ cell count, type of first AIDS-defining condition, and functional status. The stages of the system were significant predictors of survival (p = 0.0001, log-rank test). In conclusion, valid, simple clinical staging systems for patients with AIDS can be developed based on a few variables that are readily available in clinical settings. 相似文献
100.
MS Friedmann WH McDermut DA Solomon CE Ryan GI Keitner IW Miller 《Canadian Metallurgical Quarterly》1997,36(4):357-367
The primary objective of the present investigation was to examine adaptive functioning in the families of patients with a wide range of psychiatric disorders. Seven dimensions of family functioning, as measured by the Family Assessment Device (FAD), were compared across families of patients with a schizophrenia spectrum disorder (n = 61), bipolar disorder (n = 60), major depression (n = 111), anxiety disorder (n = 15), eating disorder (n = 26), substance abuse disorder (n = 48), and adjustment disorder (n = 46). Families in each psychiatric group were also compared to a control group of nonclinical families (N = 353). Results indicated that regardless of specific diagnosis, having a family member in an acute phase of a psychiatric illness was a risk factor for poor family functioning compared to the functioning of control families. However, with few exceptions, the type of the patient's psychiatric illness did not predict significant differences in family functioning. Thus, having a family member with a psychiatric illness is a general stressor for families, and family interventions should be considered for most patients who require a psychiatric hospitalization for either the onset of, or an acute exacerbation of, any psychiatric disorder. 相似文献