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91.
92.
AIM: To identify all incident cases of bladder cancer in the county of Vallès Occidental (Spain), describe their histopathological characteristics, and make comparisons with other Spanish and European areas. METHOD: The study was carried out from the Corporació Parc Taulí (Sabadell). All new cases of bladder cancer in residents of the county Vallès Occidental, a highly industrialised area of Catalonia (Spain), were included between 1992 and 1994. Incidence rates of bladder cancer were adjusted and were compared with adjusted incidence rates reported by registries in other Spanish and European countries. RESULTS: 485 new cases were identified. Transitional cell carcinomas predominated (95.5%). The majority of tumours were diagnosed in their initial stages, 75.9% being superficial and 62.6% well to moderately differentiated. Bladder cancer was more common in men than in women, but women presented tumours of worse prognosis. The mean age at diagnosis was also higher in women than men (71 vs. 66 years, p = 0.03). The adjusted incidence rate in men (52.2 cases/100,000) was among the highest of the observed areas, whereas for women (5.4 cases/100,000) was relatively low. CONCLUSIONS: The incidence of bladder cancer among men in Vallès Occidental is among the highest in Europe, and intermediate for women. The high male/female ratio seen in all Spanish areas could be attributed to the fact that women in Spain have been less exposed than men to the risk factors, or their exposure occurred more recently.  相似文献   
93.
BACKGROUND AND AIM OF THE WORK: The glutathione system has a key role in the defence against oxidative stress. To function properly, this system needs NADPH to maintain glutathione (GSH) in its reduced form. We hypothesized that the clinical problems associated with sarcoidosis might be related to a decreased anti-oxidant defence and we therefore measured the activity of the NADPH-generating enzyme glucose-6-phosphate dehydrogenase (G6PD), the GSH-regenerating enzyme glutathione reductase (GR) and indirectly the level of NADPH in red blood cells from patients with sarcoidosis. METHODS: In a population of sarcoidosis (n = 88) patients, G6PD, GR and GR activity after incubation with chromate (GR-Cr) were measured in erythrocytes. A decreased concentration of NADPH was revealed by an increased GR-Cr (> 0.6 IU/g Hb). To exclude a mutation in the G6PD gene, sequencing was performed in cases with an abnormal GR-Cr. Sarcoidosis pulmonary disease severity was evaluated by means of laboratory data, radiographic staging, HRCT scoring, pulmonary function and exercise capacity testing. RESULTS: Fourteen (29.2%) females and one (2.5%) male demonstrated an increased GR-Cr test, indicative of a decreased NADPH level. Patients with an abnormal test result demonstrated also significantly increased ACE and GR values (p < 0.05). Only one female case (of 6 tested) appeared to have a mutation in the G6PD gene. CONCLUSION: In a considerable percentage of female patients with sarcoidosis, a decreased level of NADPH in the erythrocytes was found.  相似文献   
94.
Corticotrophin-releasing hormone (CRH) plays a major role in mechanisms controlling human pregnancy and parturition. Gene regulation by progesterone may be a key point in the control of placental CRH production. Studies in primary placental ceils show that antagonism of progesterone activity or production by RU486 or trilostane leads to an increase in CRH promoter activity. This effect can be reversed by the addition of progesterone. Overexpression of progesterone receptor A (PRA) or glucocorticoid receptor resulted in a decrease in CRH promoter activity following progesterone treatment, whereas an increase in promoter activity was observed with overexpressed PR-B.  相似文献   
95.
Placental CRH plays a major role in the mechanisms controlling human pregnancy and parturition. Understanding how placental CRH production is regulated is therefore of importance. Previously we have shown that placental expression of CRH peptide and mRNA are inhibited by estrogens, in contrast to the stimulatory effects of estrogen on hypothalamic CRH production. Our current study found that in placental cells cotransfected with a CRH promoter construct and an estrogen receptor-alpha expression vector results in a differential regulation whereby 17beta estradiol (E2) decreased and the putative pure estrogen antagonist, ICI 182780,  相似文献   
96.
97.
Experiments were performed to determine the involvement of ATP-sensitive K(+) channels (K(ATP) channels) in the renal afferent arteriolar dilation that occurs during the hyperfiltration stage of insulin-dependent diabetes mellitus (IDDM). IDDM was induced in rats by streptozotocin (STZ) injection, and adequate insulin was provided to maintain moderate hyperglycemia. Sham rats received vehicle treatments. Two weeks later, afferent arteriolar function was assessed using the in vitro blood-perfused juxtamedullary nephron technique. Baseline afferent arteriolar lumen diameter was greater in STZ rats (25.9 +/- 1.1 microm) than in sham rats (20.8 +/- 1.0 microm). Glibenclamide (3 to 300 microM) had virtually no effect on afferent arterioles from sham rats; however, this K(ATP) antagonist caused concentration-dependent afferent arteriolar constriction in kidneys from STZ-treated rats, restoring lumen diameter to 20.6 +/- 1.7 microm (P > 0.05 versus sham baseline). In both groups of rats, pinacidil (a cyanoguanidine K(ATP) agonist; 0.3 to 300 microM) evoked concentration-dependent afferent arteriolar dilation, indicating the functional expression of K(ATP) channels; however, lumen diameter was increased by 73% in STZ kidneys but only by 48% in sham kidneys. The gliben-clamide-sensitive afferent arteriolar dilator response to 1 microM PCO-400 (a benzopyran K(ATP) agonist) was also accentuated in STZ kidneys. These observations suggest that increases in both the functional availability and basal activation of K(ATP) channels promote afferent arteriolar vasodilation during the early stage of IDDM, changes that likely contribute to the etiology of diabetic hyperfiltration.  相似文献   
98.
OBJECTIVE: We investigated the effect of Psychological Job Demands (PJD) on the occurrence of the clinical symptoms of common cold. METHODS: Subjects, participating in a large prospective cohort study on psychological determinants of fatigue at work, were asked to fill in a questionnaire on the occurrence of common cold during the previous four months. High PJD were considered as a potential risk factor. Other factors such as age, gender, and having young children were considered as potential confounders. RESULTS: In logistic regression analysis, the adjusted odds ratio (OR) for having a recent cold in subjects reporting high PJD vs. those reporting low PJD was 1.20 (95% confidence interval (CI), 1.08-1.33). A higher risk emerged among those with young children (OR, 1.70; 95% CI, 1.47-1.96), those having a history of asthma (OR, 1.69; 95% CI, 1.28-2.22), or being under the age of 40 (OR, 1.28; 95% CI, 1.14-1.43) and among smokers (OR, 1.23; 95% CI, 1.09-1.38). CONCLUSION: The results support an association between PJD and common cold. In spite of the almost inevitable shortcoming of a large cohort study using questionnaires, this study gave us the opportunity to study the relationship between common cold and work-related factors in a nonexperimental setting with participants observed in a natural environment with all the normal everyday hassles.  相似文献   
99.

Background  

The workplace is an ideal setting for health promotion. Helping employees to be more physically active can not only improve their physical and mental health, but can also have economic benefits such as reduced sickness absence. The current paper describes the development of a three month theory-based intervention that aims to increase levels of moderate intensity physical activity amongst employees in sedentary occupations.  相似文献   
100.
Recently, the beneficial role of steroids for acute laryngotracheobronchitis has been more clearly defined for both intubated and unintubated patients. However, corticosteroids also improve the clinical signs of airway haemangiomata. Two patients are described who illustrate how this can be a source of diagnostic confusion.  相似文献   
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