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71.
72.
Role of transforming growth factor beta in peritoneal fibrosis   总被引:11,自引:0,他引:11  
SUMMARY: Technique survival of peritoneal dialysis is seriously limited by the development of peritoneal fibrosis. the mesothelial cell layer lining the peritoneum is important in the pathogenesis of peritoneal fibrosis. Mesothelial cells are able to produce transforming growth factor beta (TGF-β), and respond to stimulation by this cytokine. In this review, we will detail the evidence available so far for the role of the complex interaction between TGF-β and mesothelial cells in the development of peritoneal fibrosis.  相似文献   
73.
74.
朝藿素D的分离和结构   总被引:6,自引:0,他引:6  
从朝鲜淫羊藿(Epimedium koreanum)地上部分分离得到一新黄酮成分(I)和一已知化合物(II)。经光谱解析,证明I的结构为5,7,3',4'-tetrahydroxy-5'-prenylflavone,命名为朝藿素D(epimedokoreanin D);II为2-hydroxy-3,4,6,7-tetramethoxy-9,10-dihydrophenanthren。  相似文献   
75.
The head nurse occupies an important position in the nursing unit Concerning leadership style, a distinction is traditionally made between consideration and initiating structure Sometimes a third style is distinguished as well, namely 'production-orientated' leadership In a study of 561 nurses from 16 general hospitals in The Netherlands, the influence of two leadership styles upon the reactions of nurses (job satisfaction, experienced meaningfulness, health complaints and absenteeism) to their work situations was examined, namely the styles of social (i e consideration) and instrumental leadership (a combination of the styles initiating structure and production-onentated) The separate effects of the two styles were studied, as well as the connection between combinations of leadership styles and reactions The results indicate that social leadership contributes positively to nurses' reactions to their job Instrumental leadership, on the other hand, leads to health complaints From the analyses of combinations of leadership styles it appears that nurses are most satisfied if the head nurse pays much attention to both dimensions of leadership For health complaints, a tendency in this directions is also found Finally, it becomes clear that nurses with a great need for autonomy prefer a different type of leadership from nurses with little need for autonomy  相似文献   
76.
77.
Platelet adhesion to fibrillar collagens (types I, II, III, and V) and nonfibrillar collagens (types IV, VI, VII, and VIII) was investigated in the presence of physiologic concentrations of divalent cations under conditions of stasis and flow. Under static conditions, platelet adhesion was observed to collagen types I through VII but not to type VIII. Under flow conditions, platelet adhesion to collagen types I, II, III, and IV was almost independent of shear rates above 300/s. Collagen type V was nonadhesive. Platelet adhesion to collagen type VI was shear rate-dependent and optimal at a rate of 300/s. Collagen types VII and VIII showed minor reactivity and supported platelet adhesion only between shear rates 100 to 1,000/s. Monoclonal antibody (MoAb) 176D7, directed against platelet membrane glycoprotein Ia (GPIa; very late antigen [VLA]-alpha 2 subunit), completely inhibited platelet adhesion to all collagens tested, under conditions of both stasis and flow. Platelet adhesion to collagen type III at shear rate 1,600/s was only inhibited for 85%. The concentration of antibody required for complete inhibition of platelet adhesion was dependent on the shear rate and the reactivity of the collagen. An MoAb directed against GPIIa (VLA-beta subunit) partially inhibited platelet adhesion to collagen. These results show that GPIa-IIa is a major and universal platelet receptor for eight unique types of collagen.  相似文献   
78.
Ultrasonically guided punctures. A modified technique   总被引:2,自引:0,他引:2  
Lindgren  PG 《Radiology》1980,137(1):235
  相似文献   
79.
This paper describes a qualitative research study which explored the practices and views of nurses working on a new Mental Health Intensive Care Unit A review of the literature identified the main aspects of intensive care provision (1) physical security, (2) characteristics of the patient group, (3) staff-patient ratios, (4) therapeutic environment and (5) multi-agency involvement Twenty-one periods of participant observation helped form the questions for a semi structured in-depth tape recorded interview in which 11 out of a total of 16 trained nurses took part The information is categorized and the discussion is informed by observation of practice The nurses perceived the following as the main issues that the physical environment is inadequate for security, that the patient group appears to have the common characteristic of being unwanted in other clinical settings, that the staff-patient ratio is inadequate and that their vision of the nature of a therapeutic environment is vague  相似文献   
80.
中药升麻的化学成分   总被引:14,自引:0,他引:14  
李从军  陈迪华  肖培根 《药学学报》1993,28(10):777-781
从中药兴安升麻[Cimicifuga dahurica(Turcz.)Maxim.]的干燥根茎中分得五个化合物,其中四个为三萜木糖甙:升麻醇-3-O-β-D-吡喃木糖甙(23R,24S)(Ⅰ),25-O-乙酰升麻醇-3-O-β-D-吡喃木糖甙(23R,24S)(Ⅱ),12-羟基升麻醇-3-O-β-D-吡喃木糖甙(23R,24S)(Ⅲ),升麻醇-3-O-β-D-吡喃木糖基(3→1)-β-D-吡喃木糖甙(23R,24S)(Ⅳ),另一个为异阿魏酸(Ⅴ)。Ⅲ和Ⅳ为新化合物,通过光谱(IR,MS,1H及13C NMR)解析确定了它们的结构,分别命名为升麻甙A(cimiside A)和升麻甙B(cimiside B)。  相似文献   
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