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51.
INTRODUCTION: The biological activity of the natriuretic peptide (NP) system is dependent on the balance between NP tissue levels and the local expression of their receptors. In the kidney, the natriuretic peptide receptor type A (NPR-A) is the principal receptor mediating NP activity and is mainly expressed in the renal medulla. An increase in circulating NP levels is well documented in chronic renal failure (CRF); however, the renal expression of NPR-A has not been evaluated in this condition. METHODS: Wistar-Han rats were submitted to right nephrectomy plus ablation of both poles of the left kidney (3/4nx; n=27) or were sham operated (Sham; n=22) and followed for up to 26 weeks post surgery. Blood pressure measurements were performed weekly. Two, 10 and 26 weeks after surgery, renal sodium and creatinine excretion were evaluated and the kidneys removed for NPR-A mRNA quantification by real-time PCR. The results of mRNA quantification are expressed in arbitrary units (AU) set as the mean value of the Sham group (Sham=1 AU), after normalization for GAPDH (p<0.05). weeks after surgery) and in elevated fractional sodium excretion (+270%, 26 weeks after surgery). Although sodium intake was similar in 3/4nx and Sham rats, blood pressure was higher in 3/4nx rats and increased progressively throughout the study. This was accompanied by a marked decrease in NPR-A mRNA levels in the renal medulla from 3/4nx animals at 2, 10 and 26 weeks post surgery. Conclusion: In 3/4nx rats, the expression of NPR-A in the renal medulla of the remnant kidney is markedly reduced from 2 weeks up to 26 weeks post surgery. It is suggested that this may contribute to the progressive increase in blood pressure, as well as to the renal fibrosis observed in 3/4nx rats.  相似文献   
52.
Objective The purpose of this study is to analyze clinical aspects and disease-free survival (DFS) in children less than 3 years of age diagnosed with low-grade astrocytoma. Methods In a period of 24 years (1980–2004), a total of 43 (5.4%) children were registered with these characteristics. Twenty-three patients had pilocytic astrocytoma, 18 diffused, and 2 mixed. Thirty-one (72.1%) children had incomplete surgical tumor resection and 12 (27.9%) had a complete tumor resection. Twelve (27.9%) patients had cranial radiotherapy and 17 (39.5%) received chemotherapy. Overall survival was recorded in 23 (53%). DFS was 50% at 250 months of follow-up for the whole group. DFS for the supratentorial group was 60% at 250 months, whereas, for the infratentorial, it was 22% at 120 months (p = 0.008). Conclusion The only favorable prognostic pattern was the supratentorial presentation. Radiotherapy and chemotherapy did not alter the outcome.  相似文献   
53.
The research describes how nursing staff on a general surgical ward in a district general hospital perceived the delivery method of nursing care in practice. The study design was based on ethnographic methods and data were collected by diary keeping and semi-structured interviews. An organizational method based on the principles of primary nursing had been implemented on the ward for 2 years prior to the study commencing. As well as talking in general terms about primary nursing, the nursing staff talked at some length about specific issues related to their practice.  相似文献   
54.
BACKGROUND: Somatisation is highly prevalent in primary care (present in 25% of visiting patients) but often goes unrecognised. Non-recognition may lead to ineffective treatment, risk of iatrogenic harm, and excessive use of healthcare services. AIM: To examine the effect of training on diagnosis of somatisation in routine clinical practice by general practitioners (GPs). DESIGN OF STUDY: Cluster randomised controlled trial, with practices as the randomisation unit. SETTING: Twenty-seven general practices (with a total of 43 GPs) in Vejle County, Denmark. METHOD: Intervention consisted of a multifaceted training programme (the TERM [The Extended Reattribution and Management] model). Patients were enrolled consecutively over a period of 13 working days. Psychiatric morbidity was assessed by means of a screening questionnaire. GPs categorised their diagnoses in another questionnaire. The primary outcome was GP diagnosis of somatisation and agreement with the screening questionnaire. RESULTS: GPs diagnosed somatisation less frequently than had previously been observed, but there was substantial variation between GPs. The difference between groups in the number of diagnoses of somatisation failed to reach the 5% significance (P = 0.094). However, the rate of diagnoses of medically unexplained physical symptoms was twice as high in the intervention group as in the control group (7.7% and 3.9%, respectively, P = 0.007). Examination of the agreement between GPs' diagnoses and the screening questionnaire revealed no significant difference between groups. CONCLUSION: Brief training increased GPs' awareness of medically unexplained physical symptoms. Diagnostic accuracy according to a screening questionnaire remained unaffected but was difficult to evaluate, as there is no agreement on a gold standard for somatisation in general practice.  相似文献   
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56.
A case-control study to evaluate the efficacy of lung cancer screening conducted by us showed that lung cancer screening may reduce the mortality of the disease up to 28%. Assuming this efficacy is unbiased, and that the screening rate is 51.6%, which was observed in the control group in the above study, the number of lung cancer deaths prevented by screening in the study period was calculated to be 47 for males and females combined. In the same study population, screen-detected lung cancer patients (N = 207) in the same study period were followed and the 7-year survival rate (46.9%) was compared to the 5-year survival rate (11.3%) obtained by the Osaka Cancer Registry, in which screen-detected lung cancer patients were only 1.8%. The number of lung cancer deaths prevented by screening, estimated by the difference in the above two survival rates, was 74 (95% confidence interval; 55–93). The number of lung cancer deaths prevented by screening estimated from the case-control study was significantly lower than that estimated from the survival analysis. This indicates that the efficacy of lung cancer screening estimated by the case-control study was within the range that could be explained by the actual long-term survivors among the screen-detected patients in the study population.  相似文献   
57.
This open multicenter study was performed in 20 hospital gynecological units in the UK. The effects of 600 mg oral mifepristone as pretreatment to vaginal prostaglandin induction of second second trimester abortion was studied in 267 women.

The primary efficacy variable was the abortion induction interval, defined as the time taken to expel the fetus from the time of administration of the first prostaglandin pessary. Induction was commenced 36 to 48 hours following mifepristone intake.

The mean abortion induction interval was 7 h. A total of 81.9% of women aborted within 12 h. There was a significant relationship between abortion induction interval and age of gestation, and a significant inverse relationship between abortion induction interval and parity.

Vomiting, pelvic pain, and nausea were the most frequently reported adverse events. Two patients required transfusion and one patient with a uterine scar from a previous cesarean section suffered a ruptured uterus and hysterotomy.  相似文献   

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59.
B超诊断腰椎间盘突出症的临床价值(附64例分析)   总被引:1,自引:0,他引:1  
报告经CT检查和临床治疗证实的64倒腰椎间盘突出症的B超检查结果,B超检出70个突出之椎间盘,CT检出73个,阳性率之比为70/73。70个突出椎间盘中,中央型5个,偏中央型20个,后外侧型44个,极外侧型1个;轻度30个,中度28个,重度12个。分型分度与临床表现及治疗选择有密切关系。B超检查与CT相此较,具有近似的诊断价值,但经济、实用,操作简单方便,值得推广。  相似文献   
60.
Abstract: The results of an intensive treatment program for patients 16–60 yr of age with de novo acute myeloid leukemia are presented. The patients were given conventional induction treatment with daunorubicin and cytarabine. Patients not entering complete remission (CR) after 1 course of daunorubicin/cytarabine were given 1 course of amsacrine/etoposide/cytarabine. Those entering complete remission received 3 consolidation courses using mitoxantrone, etoposide, amsacrine and cytarabine. One hundred and eighteen patients were enrolled. Complete remission was attained after 1–2 courses in 90 patients (76%). Another 6 patients reached CR after 3–4 induction courses for a total CR rate of 81%. If feasible, patients were offered either allogeneic or unpurged autologous bone marrow transplantation. Twenty-four patients underwent allogeneic bone marrow transplantation; 15 in first remission, 8 in second remission, 1 in early relapse. Thirty patients below 56 yr of age underwent autologous bone marrow transplantation in first remission. The overall probability of survival at 4 yr was 34%, and for patients below 40 yr of age 50%. Leukemia-free survival was 35% for the whole cohort of patients; 52% for patients below 40 yr of age. Patients undergoing allogeneic or autologous bone marrow transplantation in first remission had an overall survival of 86% and 47%, respectively, while the probability of leukemia-free survival in these groups was 87% vs. 40% at 4 yr. The CR rate and long-term results of this intensive treatment program compare favorably with other recent studies using intensive consolidation with allogeneic or autologous bone marrow transplantation or high dose cytarabine.  相似文献   
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