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After spontaneous regression of transplanted tumours, marked reduction in number of tumours was found when challenged with isogenic tumour cells. The ALS abrogates this effect. Tumour removal by surgical excision of limb and subsequent time scheduled challenge by tumour cells maximally suppress on the 10th day and continues up to the 42nd day the tumorogenic effect. Splenectomy has no effect if done before a day or 3 days after challenge but marked decrease in tumour development was seen when challenged on the 8th day after splenectomy. Amputation and splenectomy together potentiates tumour formation. Only in tumour extrication, does resistance develop up to the 42nd day from surgery. Challenging at a different site in mice with tumours, resulted in prolongation of the intervals of tumour formation. Challenge after surgical removal of tumour after a time lapse, results in marked reduction in number and size of tumours. Surgical tumour extrication after splenectomy and subsequent challenge on 11th day inhibited tumour formation. Whereas splenectomized tumour bearing mice when challenged at a heterosite did not develop resistance.  相似文献   
3.
Technology developments on the horizon promise to transform the electricity industry far from its present shape and structure. But, just as technology has played a critical role in pushing the industry to its present thrust toward competition and vertical de-integration, a sensible technology policy can make a utility or power supplier a winmer tomorrow.  相似文献   
4.
The authors present a new traveling wave method for calculating the linewidth, the frequency tuning efficiency, and a mode stability parameter for a general class of laser-diode structures. The method leads to simple semianalytic expressions which allow an easy numerical determination of the three parameters  相似文献   
5.
To make health care more responsive to patient needs, insight into patient priorities is needed. A systematic literature review, using electronic and manual searches, was made of studies on patient priorities with regard to primary health care. Data-extraction was performed by two researchers, followed by systematic analyses of study features. 57 studies were included. The aspects of care and methods used showed a wide variation. Aspects most often included were "informativeness", "humaneness" and "competence/accuracy". Based on an analysis of 19 studies, the following aspects were seen by patients as most important in more than 50% of the studies that included them: "humaneness", "competence/accuracy", "patients' involvement in decisions", "time for care", "other aspects of availability/accessibility", "informativeness", "exploring patients' needs", "other aspects of relation and communication" and "availability of special services".  相似文献   
6.
Worksite health promotion is seldom offered to workers who are low-educated and multi-ethnic, possibly due to an assumption that they are more reluctant to participate. Furthermore, little has been done to promote health at female-dominated workplaces. The main aim of this study was to investigate differences in participation among immigrant and Danish cleaners throughout a 1-year randomised controlled study tailored to cleaners and carried out in predominantly female workplaces. No significant differences in ethnicity were found in consent and participation throughout the 1-year intervention. Dropout was equally distributed among Danish and immigrant cleaners. This study indicates that a worksite health promotion intervention among a female-dominated, high-risk occupation such as cleaning can be equally appealing for Danes and immigrants. PRACTITIONER SUMMARY: This study provides insight about participation of Danish and immigrant cleaners in a worksite health promotion intervention in a predominantly female occupation. For attaining high participation and low dropout in future worksite health promotion interventions among cleaners, the intervention ought to not only target the ethnic background of the workers, but also to be specifically tailored to the job group.  相似文献   
7.
介绍GIS母线内部存在金属异物时的影响,对金属异物在不同情况下的运动规律进行了探讨和研究。  相似文献   
8.
高压SF_6断路器经多次改进在欧洲和日本已发展成第三代产品,第一代为热膨胀式断路器加助吹,将液压机构改为弹簧操动机构和变开距混合式灭弧室。第二代产品为改善开断容性电流特性发展“双容积”灭弧室和新型动态压缩灭弧室,以及双向运行触头系统等,更进一步减少分合闸操作功应用旋弧灭弧原理迫使电弧快速旋转冷却使电流零点时熄灭。第三代产品主要介绍加强操动机构的可靠性和稳定性,传输时无功消耗少,减少机构零件数量等。  相似文献   
9.
A study was conducted where the GPs in a district answered a questionnaire on reasons for hospital admission, divided into the categories: needed hospital investigation, hospital treatment, or needed care and nursing. They judged whether the admission could have been prevented. Finally, a multidisciplinary panel discussed ways to obtain better courses of admission. Of 266 admissions, 40 (15%) were due to a need for care and nursing. Ninety-seven (37%) of the admissions could be replaced by a short one-day stay, and 52 (20%) could have been postponed until the next day if that was possible. The panel discussion showed that municipalities can do more to strengthen the local professional support. It is concluded that the interface between primary care and the hospital should offer better opportunities for one-day admissions or sub-acute admissions, and that municipalities must be more aware of their responsibility for the care of fragile and ill people.  相似文献   
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