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951.
952.
Significance of random bladder biopsies in superficial bladder cancer   总被引:3,自引:0,他引:3  
OBJECTIVES: We investigated to what extent biopsies of normal-appearing urothelium taken from patients with superficial bladder cancer (Ta, T1, Tis) showed malignant disease and whether those findings had impact on therapeutical decisions. PATIENTS AND METHODS: 1033 consecutive patients presenting with Ta, T1 or Tis (carcinoma in situ) superficial bladder tumors at increased risk for recurrence underwent multiple random biopsies from normal-appearing urothelium during transurethral resection (TUR). Patients with small, primary, singular tumors (smaller or equal to 1cm) were excluded from random biopsies. RESULTS: No tumor was found in the random biopsies of 905 patients (87.6%). 128 patients (12.4%) showed urothelial bladder cancer in their random biopsies (Tis: 74, Ta: 41, T1: 12, T2: 1). In 14 patients, where transurethral resection of the primary tumor revealed no signs of malignancy, urothelial bladder cancer was detected in the random biopsy material: Ta 8 patients, Tis 5 patients and T1 one patient. 21 patients with Ta tumors and 29 patients with T1 disease showed concomitant Tis. Upstaging of the primary, resected tumor by histological examination of the random biopsy material occurred in 75 patients (7%). Altogether, due to the random biopsy results therapy was altered in 70 patients (6.8%) of our series: It changed intravesical chemotherapy to BCG in 45, provoked a second TUR in 48 and cystectomy in 15 patients. CONCLUSIONS: While the clinical significance of random biopsies is still controversial, random biopsy results had strong impact on therapeutical decisions in our series. Regarding random bladder biopsies a simple tool for the urologist to identify high risk groups of patients, we recommend them as part of the routine management of superficial bladder cancer.  相似文献   
953.
PURPOSE: To study the effect of prematurity on monocular chromatic contrast thresholds (CCT) and achromatic contrast sensitivity (ACS). DESIGN: Case-control study. METHODS: A prospective study of 59 children born at less than 33 weeks' gestation was undertaken. Subjects were identified during routine neonatal screening for retinopathy of prematurity and recalled for testing at age 7 to 13 years. Five had stage 1 retinopathy of prematurity, seven had stage 2, and three had stage 3. Sixty-eight full-term children were recruited as controls. Those with major cerebral or eye disease were excluded. The CCT and ACS were measured monocularly in the eye with better visual acuity using static, computer-generated, sinusoidal gratings, displayed on a high-resolution monitor. The CCT and ACS were determined using a randomized double-staircase reversal algorithm. The ACS was measured at five spatial frequencies (0.22, 0.44, 0.88, 1.75, and 3.50 cycles/degree), and the CCT was measured along red-green and tritan confusion axes. RESULTS: Red-green (P =.326) and tritan (P =.910) contrast thresholds and ACS (P >.394 for all spatial frequencies) were similar to the control group. CONCLUSIONS: Previous research suggests that prematurity adversely affects color vision and ACS. This study used a computerized psychophysical test that minimized the test errors inherent in many previous studies. Unexpectedly, CCT and ACS were found to be similar to full-term children.  相似文献   
954.
PURPOSE: Lens fibergenesis is a problem in several types of cataract and in the posterior capsular opacification following cataract surgery. To correct improper fiber differentiation or to prevent unwanted growth on the posterior capsule following cataract surgery requires a thorough understanding of normal and abnormal fiber formation. To this end, studies were initiated to characterize fiber differentiation in the bovine lens and in lens epithelial cell cultures. METHODS: Indirect immunofluorescence and immunoblot analysis were employed to study the expression of vimentin, beta-crystallin, gamma-crystallin, filensin, aquaporin 0 and the Na, K-ATPase catalytic subunit isoforms (alpha1, alpha2, alpha3) in bovine lens epithelium whole-mounts as well as lens epithelial cell cultures propagated in medium containing 10% bovine serum or in medium supplemented with bovine serum concentrations < or =4%. RESULTS: Three distinct cell types were observed in the bovine lens epithelium. The cells of the central zone were identified by a polarized distribution of two distinct Na, K-ATPase catalytic subunit isoforms, alpha1 to the apical (fiber side) and alpha3 to the basal (aqueous humor side) membranes. Lateral to the polarized central zone, was the germinative zone of cells, best characterized by perinuclear vimentin basket-like structures and the loss of polarized Na, K-ATPase catalytic subunit isoforms. Lateral to the germinative zone were the cells of the transition zone (meridinal rows) where expression of the lens specific proteins beta-crystallin, gamma-crystallin, filensin and aquaporin 0 as well as the lens fiber-, adipocyte- and brain glia-specific Na, K-ATPase catalytic subunit, alpha2 are expressed. The cultured cells propagated in medium supplemented with 10% serum bore no resemblance to any of the cells of the bovine lens epithelium whole-mounts. The cells propagated in the medium supplemented with the lower bovine serum levels resembled the differentiating fibers of the transition zone of the bovine lens epithelium whole-mounts as well as superficial cortical fibers. CONCLUSIONS: Since the low-serum lens epithelial cell cultures bear a remarkable resemblance to early differentiating fibers, they are reasonable models for the study of early fiber differentiation or prevention of differentiation. The culture conditions employed do not yield the polarized cells of the central zone. Nor has the function of these polarized cells in lens fluid, nutrient and ion homeostasis been determined.  相似文献   
955.
956.
This paper explores the relationship between palliative medicine and the wider medical world. It draws on data from a focus group study in which doctors from a range of specialties talked about developing palliative care for patients with heart failure. In outlining views of the organisation of care, participants engaged in a process of negotiation about the roles and expertise of their own, and other, specialties. Our analysis considers the expertise of palliative medicine with reference to its technical and indeterminate components. It shows how these are used to promote and challenge boundaries between medical specialties and with nursing. The boundaries constructed on palliative medicine's technical contribution to care are regarded as particularly coherent within orthodox medicine. In contrast, its indeterminate expertise, represented by the 'holistic' and 'psychosocial' agendas, is potentially compromising in a medical world that prizes science and rationality. We show how the coherence of both kinds of expertise is contested by moves to extend palliative care beyond its traditional temporal (end-of-life) and pathological (cancer) fields of practice.  相似文献   
957.
BACKGROUND: Traditional worksite injury surveillance methods are often ineffective for Northeastern farms employing seasonal harvest labor. Many are small farms, exempt from mandatory injury reporting. The high proportion of foreign workers and the temporary nature of the work further discourages reporting. Therefore, an alternative migrant health center-based occupational injury and illness surveillance system was piloted during 1997-1999. METHODS: Anonymous medical chart data from nine migrant health centers and four regional hospital emergency rooms was collected during 1997-1999. RESULTS: There were 516 injury/illness cases over two seasons. Joint/muscle straining (31%), falling (18%), poison ivy contact (10%), and object strikes (8%) were most common injurious events. The participation rate of health care was 75%; 130 cases were reported by hospital emergency rooms; and optimal health center participation was associated with: being a farmworker-dedicated program, and including the chart reviewer in the health center's decision to participate. CONCLUSIONS: Further development of a medical records-based surveillance system should include hospital emergency rooms and focus on identified health center performance factors.  相似文献   
958.
BACKGROUND: Prostate-specific antigen (PSA) testing for prostate cancer is controversial. Demand for PSA testing is likely to rise in the UK, Australia and other western countries. Primary care needs to develop appropriate strategies to respond to this demand. OBJECTIVES: Our aim was to compare the effectiveness of educational outreach visits (EOVs) and mailout strategies targeting PSA testing in Australian primary care. METHODS: A randomized controlled trial was conducted in general practices in southern Adelaide. The main outcome measures at baseline, 6 months and 12 months post-intervention were PSA testing rates and GP knowledge in key areas relating to prostate cancer and PSA testing. RESULTS: The interventions were able to demonstrate a change in clinical practice. In the 6 months post-intervention, median PSA testing rate in the EOV group was significantly lower than in the postal group, which in turn was significantly lower than the control group (P < 0.001). Statistically significant differences were not, however, maintained in the 6-12 month post-intervention period. The EOV group, at 6 months follow-up, had a significantly greater proportion of "correct" responses than the control group to questions about prostate cancer treatment effectiveness (P = 0.004) and endorsement of PSA screening by professional bodies (P = 0.041). CONCLUSIONS: Primary care has a central role in PSA testing for prostate cancer. Clinical practice in this area is receptive to evidence-based interventions.  相似文献   
959.
The paper focuses on the redistribution of medical work within primary health care teams. It reports the results of the analysis of interviews with general practitioners, practice nurses and managers, undertaken as part of an ethnographic study of primary care organisation and practice during a period of rapid organisational change. By examining the ways in which the respondents account for how work is being redefined and redistributed, we explore how current government policy and professional discourses combine to reconfigure both the identities of those who work in primary care and the nature of patienthood. In particular, we show how general practitioners are being reconfigured as medical specialists or consultants in ways that seem to depart radically from earlier claims that general practice is a distinctive field of social or biographical medicine. Within this new discourse medical work is distributed between doctors, nurses and unqualified staff in ways which make explicit the reduction of general practice work to sets of biomedical problems or tasks. At the same time, the devolution of much general practice work to less qualified and cheaper personnel is justified by drawing on a discourse of person-centred medicine.  相似文献   
960.
OBJECTIVES: There has been a growing recognition of the importance of contextual influences on health outcomes. This article examines community-level influences on 5 reproductive wellness outcomes in Uttar Pradesh, India. METHODS: Multilevel modeling is used to estimate household and community-level effects on wellness, with hierarchically organized data from a statewide survey of villages, urban blocks, households, women, health providers, and staff. RESULTS: The household and community have a strong contextual influence on wellness, although the models explain more of the variation in outcomes between households than between communities. CONCLUSIONS: Communities influence wellness outcomes through the socioeconomic environment and the characteristics of the health infrastructure. The specific dimensions of the community and health infrastructure varied between the outcomes.  相似文献   
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