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381.
After an 8-week placebo period, 73 patients whose diastolicblood pressures were between 90 and 110 mmHg were randomly assignedto receive 125 µg (low dose) or 500 µg of cyclopenthiazide(standard dose) for a period of one year. Blood pressure wasmeasured in the patient's home by the same observer at two-weeklyintervals during an 8-week placebo run-in period, every 4 weeksfor a further 12 weeks and at 24, 36 and 52 weeks thereafter.Serum potassium, urate, glucose, glycosylated haemoglobin, totaland HDL cholesterol, and apolipoproteins were measured at theend of the placebo period and at 4, 8, 24 and 52 weeks of activetreatment. Twelve of the 73 patients had an inadequate antihypertensiveresponse—five on the higher dose and seven on the lowerdose. One patient receiving 500 µg was withdrawn becauseof adverse effects. In the remaining 60 patients, systolic anddiastolic blood pressures were significantly reduced when comparedwith pretreatment values in both treatment groups throughoutthe one year period. The decreases in blood pressure were notsignificantly different from each other (p>0.65). Three patientson 500 µg required potassium supplements. Maximum decreasesin the serum potassium of 0.52 mmol/l(500 µg dose) and0.14 mmol/l(125 µg dose) were observed at 24 weeks oftreatment in the remaining 57 patients. The differences betweenthe two doses at this time were statistically significant (p< 0·05), as were the increases in serum urate observedat 4, 8 and 24 weeks (p<0.05). Five hundred micrograms ofcyclopenthiazide increased total serum cholesterol at eightand 24 weeks (0.35, 0.36 mmol/l respectively) when comparedwith pretreatment values (p<0.01) and almost achieved statisticalsignificance when compared with the corresponding low dose value(p = 0.066). This study confirms that 125 µg of cyclopenthiazideis a useful antihypertensive agent with a favourable metabolicprofile which is maintained in the long term.  相似文献   
382.
Development of an in vivo model of human multiple myeloma bone disease   总被引:3,自引:3,他引:3  
Alsina  M; Boyce  B; Devlin  RD; Anderson  JL; Craig  F; Mundy  GR; Roodman  GD 《Blood》1996,87(4):1495-1501
Osteolytic bone destruction and its complications, bone pain, pathologic fractures, and hypercalcemia, are a major source of morbidity and mortality in patients with multiple myeloma. The bone destruction in multiple myeloma is due to increased osteoclast (OCL) activity and decreased bone formation in areas of bone adjacent to myeloma cells. The mechanisms underlying osteolysis in multiple myeloma in vivo are unclear. We used a human plasma cell leukemia cell line, ARH-77, that has disseminated growth in mice with severe combined immunodeficiency (SCID) and expresses IgG kappa, as a model for human multiple myeloma, SCID mice were irradiated with 400 rads and mice were injected either with 10(6) ARH-77 cells intravenously (ARH-77 mice) or vehicle 24 hours after irradiation. Development of bone disease was assessed by blood ionized calcium levels, x-rays, and histology. All ARH-77, but none of control mice that survived irradiation, developed hind limb paralysis 28 to 35 days after injection and developed hypercalcemia (1.35 to 1.46 mmol/L) a mean of 5 days after becoming paraplegic. Lytic bone lesions were detected using x-rays in all the hypercalcemic mice examined. No lytic lesions or hypercalcemia developed in the controls. Controls or ARH-77 mice, after developing hypercalcemia, were then killed and bone marrow plasma from the long bones were obtained, concentrated, and assayed for bone-resorbing activity. Bone marrow plasma from ARH-77 mice induced significant bone resorption in the fetal rat long bone resorption assay when compared with controls (percentage of total 45Ca released = 35% +/- 4% v 11% +/- 1%). Histologic examination of tissues from the ARH-77 mice showed infiltration of myeloma cells in the liver and spleen and marked infiltration in vertebrae and long bones, with loss of bony trabeculae and increased OCL numbers. Interestingly, cultures of ARH-77 mouse bone marrow for early OCL precursors (colony-forming unit-granulocyte- macrophage [CFU-GM]) showed a threefold increase in CFU-GM from ARH-77 marrow versus controls (185 +/- 32 v 40 +/- 3 per 2 x 10(5) cell plated). Bone-resorbing human and murine cytokines such as interleukin- 6 (IL-6), IL-1 alpha or beta, TGF-alpha, lymphotoxin, and TNF alpha were not significantly increased in ARH-77 mouse sera or marrow plasma, compared with control mice, although ARH-77 cells produce IL-6 and lymphotoxin in vitro. Conditioned media from ARH-77 cells induced significant bone resorption in the fetal rat long bone resorption assay when compared with untreated media (percentage of total 45Ca released = 22% +/- 2% v 11% +/- 1%). This effect was not blocked by anti-IL-6 or antilymphotoxin (percentage of total 45Ca released = 19% +/- 1% and 22% +/- 1%, respectively). Thus, we have developed a model of human multiple myeloma bone disease that should be very useful to dissect the pathogenesis of the bone destruction in multiple myeloma.  相似文献   
383.
384.
1α,25-Dihydroxyvitamin D3 (1,25-(OH)2D3), the biologically active form of vitamin D3, not only plays a major role in mammalian calcium and phosphorous homeostasis but also exerts pleiotropic effects on cell proliferation, differentiation and the immune system. Further, vitamin D is believed to play a significant role in the prevention of colon, prostate, and breast cancer and in reducing the risk of autoimmune diseases. To gain insight into the mechanism whereby vitamin D can have such diverse actions, we have employed microarray technology. We studied the effect of a single dose of 1,25-(OH)2D3 on gene expression in the intestine of vitamin D-deficient rats. Within 6 h, 1,25-(OH)2D3 stimulates the expression of several phase I and phase II biotransformation genes. There is also an increased expression of antioxidant genes. These results support the idea that vitamin D is a significant factor in detoxification and protection against environmental toxins.  相似文献   
385.
人参的分析——Ⅳ.人参皂甙的高效液相色谱测定   总被引:13,自引:0,他引:13  
本文报道了人参中六种主要皂甙(Rb_1,Rb_2,Rc,Rd,Re,Rg)的HPLC测定法,用氨基键合相柱,示差折光检测,流动相为甲醇中乙腈—乙二醇—醋酸铵(0.14 mol/L)(30:70:5:10.6),同时还改进了纯化方法,此法快速、重现性好,与薄层比色法比较结果基本一致。  相似文献   
386.
Forensic mental health nurses (FMHN) provide care to address the needs of people who have mental illnesses across a range of diverse settings. The Clinical Reasoning Cycle (CRC) has been identified as a potential framework to assist FMHNs; however, adaptations were required to reflect the unique nature of the clinical setting. This study aimed to explore adaptations made to determine suitability prior to implementation in practice. Nominal Group Technique was used to explore suggested adaptations determined from a previous study and reach a consensus on the changes. Fourteen senior nurses from a state-wide Forensic mental Health (FMH) service participated. A consensus was reached for two proposed changes. Data were analysed using thematic analysis. Three main themes were interpreted from the data; FMH adaptations are warranted, the focus of the CRC, and who owns the cycle? Nurses in this study considered the need to include offence and risk issues due to the impact these factors have on the therapeutic relationship and cognitive bias; however, they also identified the need to focus on recovery-oriented care while engaging in clinical reasoning. Nurses in this study also expressed some reluctance for nursing to ‘own' the model, due to concern that ownership may cause division among the team or result in inconsistency in care. However, some participant's suggested the CRC with adaptations assisted FMH nurses to articulate their specialist skills and knowledge to others and highlight the nursing contribution to care. Further work is needed to finalize adaptations with a focus on engaging the consumer carer workforce and interdisciplinary team.  相似文献   
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