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991.
992.
Zusammenfassung Die Wirkung des ?thylazetatextraktes von Chrysanthemum morifolium auf P. falciparum wurde in vitro untersucht. W?hrend sich die Parasit?mie bei der Kontrollgruppe bis zu 10. 90 % entwickelte, wurde bei dem mit ?thylazetatextrakt in einer Konzentration von 100 μg/ml Medium am 5. Tag der Kultur eine signifikante Hemmwirkung auf die Parasiten beobachtet. Die Parasit?mie blieb bei 1. 00 %.
Diese Arbeit wurde durch die Stiftung von “National Nature Science Foundation of China” finanziert (No. 39260066)  相似文献   
993.
Sixty-seven patients with 68 stage T4 carcinomas of the skin of the head and neck were treated with radical radiotherapy at the University of Florida between October 1964 and November 1989. Thirty-three lesions were previously untreated and 35 were recurrent. Twenty-nine lesions were squamous cell carcinomas, 37 were basal cell carcinomas, and 2 were basosquamous carcinomas. Minimum follow-up was 2 years. The 5-year local control, local control including surgical salvage, and cause-specific survival probabilities were 53%, 74%, and 75%, respectively. Local control rates with radiotherapy alone were poorer in patients with recurrent lesions (41% vs. 67%, p = .07) or bone involvement (40% vs. 62%, p = .08). Results were analyzed by multivariate methods using local control, local control with surgical salvage, and cause-specific survival as endpoints. The parameters analyzed were histology; size of primary lesion; previous treatment (previously untreated vs. recurrent); involvement of bone, nerve, or cartilage; and skeletal muscle invasion. Three important prognostic factors were identified, each predictive of poorer ultimate local control and cause-specific survival rates: (a) bone involvement (p < .01); (b) recurrent lesions (p < .01); and (c) nerve involvement (p < .02). Radiotherapy alone can control advanced carcinomas of the skin of the head and neck, although lesions that have recurred after prior treatment and those with involvement of bone or nerve are associated with a lower likelihood of cure.  相似文献   
994.
Congenital nephrogenic diabetes insipidus (DIR) Is a rare X-linkedhereditary disorder in which the renal collecting duct Is unresponsiveto arginine vasopressin; thus, the urine is consistently hypotonicto plasma. Recently, the association between the V2 receptorgene (AVPR2) and DIR has been proven. We have determined thegene sequence of four family members, from three generations,of a large North American family with CNDI who were originallypart of the study used to formulate the Hopewell hypothesis.It had been proposed that a single DIR gene defect was Introducedto North America by a member of an Ulster Scot kindred arrivingon the ship Hopewell In 1761. DNA sequencing of the AVPR2 hasIdentified a single base transversion from G  相似文献   
995.
Staged arteriovenous reversal has been successfully established forrevascularization of severely ischemic limbs since 1984. The authors tried to constrict thecentral venous limb immediately after the arteriovenous fistula formation to make the pres-sure distal to the anastomosis raising to its maximum to shorten the time required for thedistal valves to become incompetent. Thus, the revascularization of the severely ischemiclimbs may be established much sooner than the staged arteriovenous reversal, and more di-seased limbs will be saved. Forty-two patients with a total of 60 upper and lower limbshave been operated on with good results.  相似文献   
996.
We report here the complete nucleotide sequence and predicted polyprotein sequence of HeLa cell-adapted human rhinovirus 16 (HRV16). This virus is more suitable than human rhinovirus 14 (HRV14) for clinical studies, and its growth and physical properties are favorable for biochemical and crystallographic analysis. The complete message-sense RNA genome of HRV16 is composed of 7124 bases, not including the poly(A) tail. An open reading frame, extending from base 626 to 7084 predicts a polyprotein containing 2152 amino acid residues. Comparison with other rhinovirus sequences shows HRV16 is much more representative of human rhinoviruses than HRV14. No apparent relationship was found between receptor group and amino acid sequence in VP1, the capsid protein bearing the binding site for the intercullular adhesion molecule-1 (ICAM-1) in both HRV14 and HRV16.Genbank accession number: L24917.  相似文献   
997.
The immortalization of progenitor cells from embryonic murine hippocampus using oncogene‐carrying retroviral vectors is described. Use of a vector encoding the oncogene v‐myc results in lines of nestin‐positive progenitor cells. Limited differentiation ensues if the cells are cultured in the presence of dibutyryl cyclic adenosine monophosphate. In contrast, use of a vector in which the extracellular portion of the epidermal growth factor (EGF) receptor is fused to the neu tyrosine kinase generates lines of pluripotential nestin‐positive progenitor cells, which differentiate upon withdrawal of EGF into neurons and glia. Differentiated neurons expressing action potentials and neurotransmitter receptors make up a high proportion of the cells. These cell lines are useful tools to investigate the characteristics of differentiating neurons and glia, as well as to screen neuroactive drugs. This work has been reported in preliminary form as an abstract (1996 Society for Neuroscience Abstract, #606.20, p. 1537).  相似文献   
998.
Building on the foundation of understanding and comprehensive assessment of battered women, this article addresses service planning and intervention. Strategies are approached within the framework of a Crisis Paradigm developed from field research with battered women and their families. They include mechanisms such as support groups which link crisis service to the long-term needs of battered women, and systematic approaches to removing the obstacles which keep women victimized. An Assessment and Service Planning Guide (ASPG) is proposed for inclusion in routine health care of abused women. The article concludes with strategies for preventing violence at interpersonal and societal levels.  相似文献   
999.
1000.
The faculty maintain close contact with the resource persons and are aware of their interaction with students on a weekly basis. Faculty and resource persons exchange observations, assessments, suggestions and problems they have either anticipated or experienced. The resource persons report that as students gain from the experiences, so do they. In particular, resource persons state interactions with students have stimulated them to increase their own clinical inquiry. A head nurse, functioning as a resource person, recently told the members of the Nursing Curriculum Committee she wished she had had such a course seven years ago when she was a senior in the program (S. Collier, personal communication, October 1987). She further elaborated that the learning opportunities she sees students experiencing today would have been invaluable to her and her peers as they began their professional nursing careers. We, the authors, believe individual learning opportunities with nurse leaders as resource persons is a unique, invaluable experience for nursing leadership students. These interactions provide a variety of learning opportunities sufficient for undergraduate students to develop beginning leadership skills, while also narrowing the education-practice gap. These experiences enhance the students' orientation to "real-world" nursing leadership and management. Students recognize the uniqueness of this teaching-learning strategy and value the time spent with resource persons. They frequently report never dreaming "that such problems have to be dealt with." They agree that learning with resource persons provides an essential ingredient for reinforcing the theoretical concepts of nursing leadership and putting classroom lectures into action.  相似文献   
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