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61.
小井眼技术的发展与评价   总被引:1,自引:0,他引:1  
本文报道了用氯化铁水合物催化肉桂酸和异戊醇的酯化作用,探讨了氯化铁催化合成肉桂酸异戊酯的条件。  相似文献   
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花是爱的礼物,也是纪念、抒发对死者悲伤的情感.2008年5月12日北京时间14:28时,四川汶川发生8.0级大地震,造成至少500万人无家可归.  相似文献   
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Cell-mediated immunity and cytokines are probably involved in the pathogenesis of malaria. To investigate the role and the activity of different immune cells, we measured levels of tumour necrosis factor-(TNF-alpha), gamma interferon (IFN-gamma) and several interleukins (IL-2, IL-4, IL-6 and IL-10) in children with mild (MM) and cerebral (CM) Plasmodium falciparum malaria and compared them with those of healthy children from Guadalupe--Lobata District, St. Tomé Island, where malaria is mesoendemic. Both groups of patients had significantly higher levels of IL-6, IL-10 and TNF-alpha than controls. For IL-2, IL-4 and IFN-gamma we found no difference between the groups. However, 24 h after admission the levels of IL-10 and IL-6 were significantly higher in CM than in MM patients, although 7 days after treatment they returned to normal levels, similar to those found in control children. Therefore, TNF-alpha IL-6 and IL-10 increase during Plasmodium falciparum attacks in all children, not only in those with cerebral malaria. This finding suggests the activation of the monocyte/macrophage system during the early stage of clinical malaria.  相似文献   
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The crystal structure is reported of a complex between the dodecanucleotide sequence d(CGCGAATTCGCG)2and an analogue of the DNA binding drug Hoechst 33258, in which the piperazine ring has been replaced by an amidinium group and the phenol ring by a phenylamidinium group. The structure has been refined to an R factor of 19.5% at 2.2 A resolution. The drug is held in the minor groove by five strong hydrogen bonds, together with bridging water molecules at both ends. There are few other contacts with the floor of the groove, indicating a lack of isohelicity with the groove and suggesting (i) that the observed high DNA affinity of this drug is primarily due to the array of hydrogen bonds and (ii) that these more than compensate for its poor isohelicity.  相似文献   
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OBJECTIVE: To examine and describe the relation between age and disposition in patients undergoing tracheostomy. DESIGN: Retrospective analysis of a statewide database. SETTING: All acute care hospitals in New York state. PATIENTS: All patients (n = 6,353) > or = 18 yrs of age who were discharged from the hospital during 1993 with a final diagnosis-related groups code of 483. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The final disposition, according to six disposition codes (other acute care facility, residential healthcare facility, other healthcare facility, home, home healthcare services, and death) was examined for the entire population. Cost per case was assumed to equal the average statewide Medicaid rate. An inverse relation between survival rate and age was observed, which resulted in an age-related increased cost per survivor. Also, survivors in older age groups had an increased rate of discharge to residential healthcare facilities. There was a negative, albeit less marked, effect of older age on the rates of survivors discharged to home and to other healthcare facilities. CONCLUSIONS: Care of patients who undergo tracheostomy for prolonged mechanical ventilation is expensive. The older the patient, the less satisfactory the outcome from an economic, clinical, and possibly social perspective.  相似文献   
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