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21.
Raph Hamers Sander Bontemps Marjan van den Akker Ruy Souza Júlio Penaforte Niels Chavannes 《Primary care respiratory journal》2006,15(5):299-306
AIMS: The developing world is particularly at risk of an increasing health burden due to an increased prevalence of Chronic Obstructive Pulmonary Disease (COPD) secondary to increasing tobacco consumption. However, research is scarce. The objectives of this study were to assess the current competence for diagnosing COPD in primary care in a resource-limited setting in Brazil, and to develop a local patient profile for case-finding. METHODS: 34 general practitioners (GPs) in five areas of northern Brazil recruited adult patients with principal complaints of cough and/or shortness of breath who then had spirometry (n = 142). RESULTS: For the dichotomous variable 'COPD' the degree of agreement between GP diagnosis (n = 64, 18.3%) and spirometric outcome (n = 36, 25.4%) was poor, with Kappa = 0.055 (SE 0.087) and DOR = 1.35. False-positive and false-negative diagnosis proportions were 19.8% and 75%, respectively. Independent risk factors were 'smoking history of more than five pack years' and 'presence of both dyspnoea and cough'. It requires the testing of 2.2 smokers with more than five pack years to detect one patient at risk. CONCLUSIONS: COPD is a common yet underdiagnosed disease in Brazilian primary care. Spirometry improves diagnostic competence and case-finding substantially. If applied in a pre-selected high-risk population, we believe spirometry can be a cost-effective diagnostic tool for case-finding in the resource-limited setting. This study provides important baseline information for effective guideline implementation. 相似文献
22.
Carla Santos Araújo Roberto Roncon Albuquerque Mónica Moreira Rodrigues Benedita Sampaio Maia Adelino F Leite Moreira Manuel Pestana 《Revista portuguesa de cardiologia》2006,25(4):419-427
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
23.
Roberto Rivera-Luna Marta Zapata-Tarrés Aurora Medina-Sansón Enrique López-Aguilar Ana Niembro-Zúñiga J. Amador Zarco Alfonso Marhx-Bracho Fernando Rueda-Franco Leticia Bornstein-Quevedo 《Child's nervous system》2007,23(5):543-547
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
24.
Eulogio Valentín Jesús Zueco Almudena Nieto Rafael Sentandreu Lucas del Castillo Agudo 《Current genetics》1992,21(4-5):291-293
Summary The RPS5 gene has been characterised through its ability to reduce invertase production by the SUC5 gene. In this paper we show that RPS5 acts by maintaining low levels of SUC5 mRNA. We also show that RPS5 acts on the SUC1 and SUC4 genes but not on SUC2 and SUC3, which are members of the SUC family. RPS5 also shows a pleiotropic effect on the amount of mitochondrial cytochromes. 相似文献
25.
V Rafnsson S G Jóhannesdóttir H Oddsson H Benediktsson H Tulinius G Magnússon 《Scandinavian journal of work, environment & health》1988,14(3):197-200
A retrospective cohort study of mortality and cancer morbidity was carried out among 295 marine engineers and 182 machinists with special regard to cancer of the lung. The cohort was defined as all graduates from engineering and machinists school in Iceland during 1936-1955. During vocational training, as well as in their professional lives, marine engineers and machinists are exposed to asbestos, different kinds of mineral oils, and exhaust gases with marked individual variation as regards mode and magnitude of exposure. For deaths occurring between 1951 and 1982 information was obtained from the Statistical Bureau of Iceland. Significantly increased standardized mortality ratios were determined for cancer of the trachea, bronchus, and lung for the entire cohort. Record linkage with the Cancer Register revealed 36 cancers in the period 1955-1982. No statistically significant excess was found for the overall cancer incidence or for the incidence of cancer at any particular site. A special survey of smoking status showed that cigarette smoking was not as common among the subjects of the cohort as among the general male population in Reykjavik. These results support the suggestion that the increased mortality of lung cancer in the study group had a causal relationship to occupational exposure, particularly to asbestos exposure. 相似文献
26.
A López Granados M Anguita Sánchez M D Mesa Rubio M Franco Zapata R Vivancos Delgado G Bueno Ferrer J Suárez de Lezo F Vallés Belsúe 《Revista espa?ola de cardiología》1991,44(3):210-212
Almost 90% of primary acute pericarditis are idiopathic. Between specifics forms, a very low percentage of cases are due to chronic rheumatic diseases. A case of adult Still's disease (juvenile chronic rheumatoid arthritis) with acute pericarditis being the first clinical manifestation (besides fever and general syndrome) is presented. Therapy with oral prednisone was rapidly effective, and pericardial effusion resolved after 3 weeks of treatment, as echocardiography showed. 相似文献
27.
Primary pregnancy in the liver. A case report 总被引:1,自引:0,他引:1
A de A Barbosa Júnior L A de Freitas M A Mota 《Pathology, research and practice》1991,187(2-3):329-31; discussion 332-3
A case of intra-hepatic pregnancy is reported. The patient was 32 years old and presented with an acute intra-abdominal hemorrhage. At surgery a spongy 3 x 2 x 1.5 cm mass was removed from the right liver lobe. Microscopically, well developed chorionic villi appeared invading the liver tissue. The patient had a relatively uneventful recovery. 相似文献
28.
29.
F Arreola R Paniagua J Herrera S Díaz-Bensussen L Mondragón J A Bermúdez E Pérez Pastén S Villalpando 《Archives of andrology》1986,16(2):151-154
Plasma zinc and pituitary and testicular hormone concentrations were measured in two groups of male adolescents. One group comprised insulin-dependent diabetes mellitus patients, aged 14-19 years; the other, as control, included 12 healthy youngsters aged 13-19 years. Plasma concentration of zinc, prolactin, testosterone, and dihydrotestosterone were lower in diabetics than in controls, whereas the ratios of androstenedione and androstenedione to testosterone + dihydrotestosterone were higher. Plasma FSH and LH were normal. These results suggest a diminished conversion of androstenedione to testosterone and relate zinc with the 17-beta-hydroxysteroid dehydrogenase enzyme activity. 相似文献