全文获取类型
收费全文 | 3052篇 |
免费 | 0篇 |
专业分类
综合类 | 1篇 |
化学工业 | 9篇 |
建筑科学 | 1篇 |
轻工业 | 1篇 |
一般工业技术 | 1篇 |
冶金工业 | 3035篇 |
自动化技术 | 4篇 |
出版年
2016年 | 1篇 |
2012年 | 1篇 |
2010年 | 2篇 |
2007年 | 1篇 |
2005年 | 2篇 |
2003年 | 5篇 |
1999年 | 105篇 |
1998年 | 946篇 |
1997年 | 551篇 |
1996年 | 332篇 |
1995年 | 197篇 |
1994年 | 156篇 |
1993年 | 173篇 |
1992年 | 17篇 |
1991年 | 45篇 |
1990年 | 34篇 |
1989年 | 42篇 |
1988年 | 55篇 |
1987年 | 45篇 |
1986年 | 29篇 |
1985年 | 21篇 |
1983年 | 5篇 |
1982年 | 14篇 |
1981年 | 14篇 |
1980年 | 27篇 |
1979年 | 2篇 |
1978年 | 11篇 |
1977年 | 66篇 |
1976年 | 151篇 |
1975年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有3052条查询结果,搜索用时 15 毫秒
21.
22.
Repeated transfusion of small increments of blood are frequently required for the sick and premature newborn infant to correct endogenous hypovolemia and/or to replace blood obtained for laboratory monitoring purposes. Previously fresh group and type specific whole blood was used. To eliminate waste of fresh whole blood, maintain fresh red blood cell properties, eliminate the hazards of transfusing plasma and to provide a more efficient system, a pediatric frozen red cell pack (PFRCP) has been developed. Units of group O rr red blood cells are glycerolized using a high glycerol method. The glycerolized red blood cells are separated into three equal aliquots and frozen. When needed, the PFRCP are deglycerolized by a modified procedure using the IBM Cell Processor. During a six month period, 71 infants were given 153 separate transfusions of deglycerolized red blood cells using 102 PFRCP prepared from 34 units of red blood cells. Red blood cell recovery, hematocrit, white blood cell removal, residual glycerol, total protein, and supernatant hemoglobin levels were measured. Clinical response was followed and found to be excellent. 相似文献
23.
The catecholamine hypothesis of progressive spinal cord necrosis following mechanical trauma was investigated with the histofluorometric method. Forty-four adult mongrel dog were examined as control, L1 crush-injured, and crush-injured with prior T1 total transection groups. In crush injured dogs, catecholamines were present in a 1 cm length of white matter at the crush site, with the greatest accumulation in the deep lateral and ventral funiculi. Gray matter fluorescence was not enhanced. Prior transection did not abolish the intense accumulation of catecholamines at the site of the cord injury. We propose that the catecholamines accumulating at the cord injured site are not central in origin, but represent an uptake mechanism into white matter as a reflection of cord microperfusion. 相似文献
24.
25.
26.
27.
28.
An innovative model for organising social services in a community, the Imbrication Model, is contrasted with two traditional models, the Entrepreneurial and the Umbrella Agency. The structural characteristics and dynamics of the three models are illustrated with actual case histories. Imbrication Model calls for the interlocking of personnel from several agencies, with the purpose of redirecting the dysfunctional interagency rivalry prevalent in the traditional models. Imbrications at all organisational levels--Board of Directors, Administrators and Staff--facilitate adoption of the superordinate goal of providing clients with the best services available, regardless of which particular agency delivers the service. Few observers of the current social service scene would challenge the statement that needs for service are unlimited and resources limited. In the USA the imbalance between needs and resources persists despite a decade of massive governmental programmes intended to alleviate social ills. Recent substantial cutbacks in federal funds, moreover are not likely to improve the situation. The resource shortage involves more than a limitation of funds. Deliverers of service and competent programme administrators are also on critically short supply. These shortages are more often than not exacerbated by a chronic spirit of competition among agencies and programmes at the local level. Three organizational models for the delivery and administration of social services, two conventional and one of more recent date, are examined in this article. The innovative model, which has been named the Imbrication Model, explicitly calls for redirecting interagency rivalry and competition. Its ambitious goal is to integrate the efforts of those attempting to meet a community's social service needs. 相似文献
29.
30.