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71.
7-(4,7-二取代香豆素-3-乙酰氨基)头孢菌素的合成   总被引:2,自引:0,他引:2  
范华娟  段廷汉  李明华   《药学学报》1989,24(3):175-181
本文根据构效关系,设计并合成了17个7-(4,7-二取代香豆素-3-乙酰氨基)头孢菌素衍生物。其缩合方法采用酰氯法、Vilsmeier试剂法及混合酐法。初步体外抑菌试验表明,化合物对革兰氏阳性菌和少数革兰氏阴性菌有较强的抗菌作用。进一步药理试验尚在进行。  相似文献   
72.
We isolated and characterized eight polymorphic microsatellite loci for redside dace (Clinostomus elongatus), a colorful North American cyprinid that is threatened or endangered throughout most of its range. The number of alleles per locus ranged from three to eighteen, with observed heterozygosity ranging from 0.31–0.92. Cross-amplification revealed that these markers will also be useful for examining closely related and more distantly related species, including the rosyside dace (Clinostomus funduloides), Lahontan redside shiner (Richardsonius egregius), hornyhead chub (Nocomis biguttatus), and central stoneroller (Campostoma anomalum). These microsatellite loci will provide a valuable set of tools for examining fine and coarse scale population structure, exploring reproductive success, and testing outcomes of proposed conservation initiatives (e.g. captive breeding and translocation of wild individuals) for redside dace.  相似文献   
73.
74.

Purpose of Review

Physical activity is increasingly recommended for chronic pain. In this review, we briefly survey recent, high-quality meta-analyses on the effects of exercise in human chronic pain populations, followed by a critical discussion of the rodent literature.

Recent Findings

Most meta-analytical studies on the effects of exercise in human chronic pain populations describe moderate improvements in various types of chronic pain, despite substantial variability in the outcomes reported in the primary literature. The most consistent findings suggest that while greater adherence to exercise programs produces better outcomes, there is minimal support for the superiority of one type of exercise over another. The rodent literature similarly suggests that while regular exercise reduces hypersensitivity in rodent models of chronic pain, exercise benefits do not appear to relate to either the type of injury or any particular facet of the exercise paradigm. Potential factors underlying these results are discussed, including the putative involvement of stress-induced analgesic effects associated with certain types of exercise paradigms.

Summary

Exercise research using rodent models of chronic pain would benefit from increased attention to the role of stress in exercise-induced analgesia, as well as the incorporation of more clinically relevant exercise paradigms.
  相似文献   
75.
The Royal College of Anaesthetists, the Royal College of Physicians, the Intensive Care Society and the Resuscitation Council (UK) have published new resuscitation standards. The document provides advice to UK healthcare organisations, resuscitation committees and resuscitation officers on all aspects of the resuscitation service. It includes sections on resuscitation training, resuscitation equipment, the cardiac arrest team, cardiac arrest prevention, patient transfer, post-resuscitation care, audit and research. The document makes several recommendations. Healthcare institutions should have, or be represented on, a resuscitation committee that is responsible for all resuscitation issues. Every institution should have at least one resuscitation officer responsible for teaching and conducting training in resuscitation techniques. Staff with patient contact should be given regular resuscitation training appropriate to their expected abilities and roles. Clinical staff should receive regular training in the recognition of patients at risk of cardiopulmonary arrest and the measures required for the prevention of cardiopulmonary arrest. Healthcare institutions admitting acutely ill patients should have a resuscitation team, or its equivalent, available at all times. Clear guidelines should be available indicating how and when to call for the resuscitation team. Cardiopulmonary arrest should be managed according to current national guidelines. Resuscitation equipment should be available throughout the institution for clinical use and for training. The practice of resuscitation should be audited to maintain and improve standards of care. A do not attempt resuscitation (DNAR) policy should be compiled, communicated to relevant members of staff, used and audited regularly. Funding must be provided to support an effective resuscitation service.  相似文献   
76.
The delivery of anesthesia services is at a crossroads in the United States. In 1967, there were two certified registered nurse anesthetists (CRNAs) for every anesthesiologist providing anesthetics, and the numbers are nearly equal today. A CRNA manpower forecasting model is developed in this article that shows CRNA supply and requirements from 1990 through 2010. Two estimates of CRNA shortage are presented, one based on the current trend of anesthesiologists replacing CRNAs and another assuming that CRNAs are involved in every anesthetic under anesthesiologist supervision. The results imply that more than a twofold increase in CRNA school enrollments is needed just to fill conservative baseline needs given the predicted growth in operations in all settings. Limiting anesthesiologists to a supervisory role, at the other extreme, would require a doubling of CRNAs by 2010 and an even greater expansion of CRNA schools. However, it is estimated that reversing CRNA manpower trends could save society between $750 million and $1.2 billion annually.  相似文献   
77.
BACKGROUND: The purpose of this study was to search for a more effective transfusion-monitoring system than the existing system of retrospective peer review. STUDY DESIGN AND METHODS: This research used a study-control, preintervention and postintervention design, to evaluate the effectiveness of a prospective physician self-audit transfusion-monitoring system that functioned without the direct involvement of transfusion service physicians. This research also evaluated the effectiveness of issuing to physicians a memo with transfusion guidelines. Three process indicators were used to assess physician behavior at various stages of the blood-ordering process: 1) the number of crossmatches ordered per admission, 2) the transfusion-to- crossmatch ratio, and 3) the number of blood units returned to the laboratory after physician self-auditing. The study used two outcome indicators to reflect overall blood utilization: 1) the percentage of patients who received red cell transfusions and 2) the number of blood units transfused per recipient each month. RESULTS: The prospective physician self-audit system implemented at the study hospital did not reverse physician transfusion decisions, and the process of issuing to physicians a memo with transfusion guidelines at the control hospital failed to reduce blood usage. However, a transient reduction in blood utilization was observed at the study hospital. CONCLUSION: The reduction was hypothesized to be due to a Hawthorne effect, in which observed behavior is affected by the subject's awareness of the research study.  相似文献   
78.
目的:将可注射纳米骨材料与共培养的兔肾血管内皮细胞和兔骨髓间充质干细胞诱导的成骨细胞复合,并构建可注射细胞型纳米组织工程骨,观察它们体外培养的相容性. 方法:实验于2003-09/2004-11在苏州大学附属儿童医院完成.①实验材料:取16周龄雄性新西兰大耳白兔,体质量1.5 kg左右.②实验方法:麻醉后抽取兔骨髓,用淋巴细胞分离液分离出其中的间充质干细胞,在含体积分数为0.15牛血清的RPMI1640液中培养.骨髓间充质干细胞在条件培养基中,7 d后可见细胞变为多边形,碱性磷酸酶和Ⅰ型胶原染色阳性,形成钙结节,表现成骨细胞分化特点.采用三步梯度筛网法,获得肾血管球,5 g/L胶原酶Ⅳ37℃消化15~20 min,离心沉淀获取血管内皮细胞,在含体积分数为0.15小牛血清的M199中培养.③实验评估:免疫组织化学法进行第Ⅷ因子相关抗原鉴定,透射电镜观察细胞浆Weibel-Palade小体,间接免疫荧光法检测CD31、CD34及CD44的表达.将共培养的兔肾血管内皮细胞、成骨细胞与可注射纳米骨材料体外复合培养,进行形态学观察和功能测定. 结果:①在一定培养条件下成功诱导兔骨髓间充质干细胞向成骨细胞分化.②培养的血管内皮细胞免疫组织化学法检测第Ⅷ因子相关抗原阳性,透射电镜观察到细胞浆中的Weibel-Palade小体,间接免疫荧光法检测CD31、CD34表达阳性,CD44阴性.③共培养的兔肾血管内皮细胞、成骨细胞在可注射纳米骨材料上生长、增殖良好,细胞活性和碱性磷酸酶活性未受到影响. 结论:可注射纳米骨材料具有良好的细胞相容性,可作为骨组织工程理想的可注射载体材料.  相似文献   
79.
Cyclosporin nephrotoxicity in heart and lung transplant patients   总被引:1,自引:0,他引:1  
Twenty-two patients with heart, lung or heart and lung transplants maintained on cyclosporin for periods ranging from 3 months to 10 years developed renal insufficiency which was investigated by renal biopsy. The histopathological changes were: (i) severe vascular and glomerular damage due to thrombotic microangiopathy (TM); (ii) a form of focal segmental glomerulosclerosis (FSGS); (iii) glomerular ischaemia. Rather than being separate entities, these changes appeared to represent a spectrum of pathology, some biopsies showing all three forms of glomerular injury. In all cases the glomerular changes were accompanied by arteriolar and arterial pathology, and we identified novel ultrastructural changes in the arteriolar endothelial basal lamina. Tubular atrophy was a consistent feature, the severity of which reflected the severity of the glomerular sclerosis, and which appeared to be a consequence of glomerular loss. Our findings are consistent with the nephrotoxic effects of cyclosporin being mediated chiefly via damage to preglomerular vessels and glomerular capillary endothelium. From an analysis of the clinical aspects of these cases, the effects of cyclosporin appear to be to some extent idiosyncratic, and therefore not entirely preventable, but strict monitoring of blood cyclosporin levels is essential to minimize the risk of permanent renal damage. Monitoring urinary protein in addition to plasma creatinine may detect the onset of FSGS, as proteinuria precedes creatinine elevation.   相似文献   
80.
Cystic fibrosis (CF), a genetic disorder, is characterized by chronic pulmonary infection/inflammation which leads to respiratory failure. The presence of anti-neutrophil cytoplasmic autoantibodies (ANCA) has previously been observed in the sera of patients with CF. In view of the known relationship of ANCA with primary vasculitis and of their putative pathogenetic role in these disorders, we studied the presence, specificity and isotype of ANCA and their clinical associations in 66 adult CF patients. None of the 66 CF samples had autoantibodies to the major ANCA antigens, proteinase 3 or myeloperoxidase. However, 60/66 (91%) CF samples contained IgG and 55/66 (83%) IgA, autoantibodies to bactericidal/permeability increasing protein (BPI), a recently characterized ANCA specificity. All the IgA anti-BPI-positive samples were also IgG anti-BPI-positive. The autoantibody specificity was confirmed by inhibition assay and immunoblotting of CF sera against a neutrophil granule preparation. Furthermore, in this cross-sectional study, anti-BPI levels were inversely correlated with the observed reductions in FEV1 and FVC (IgA anti-BPI and FEV1: r = 0.508, <it>p</it> &lt; 0.0001), and both IgG and IgA anti-BPI levels were higher in CF patients with secondary vasculitis (<it>n</it> = 6) than in those without (<it>p</it> &lt; 0.05). ANCA with specificity for BPI were present in the majority of CF sera in this study and autoimmune processes may be associated with the development of pulmonary injury in CF.   相似文献   
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