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1.
The dissolution of stainless steel welding fumes produced by manual metal arc (MMA) and metal inert gas (MIG) techniques was studied by transmission electron microscopy and quantitative x ray microanalysis in the lungs of rats after inhalation exposure. Rats exposed to stainless steel fumes generated by MMA were found to have two particle populations of different behaviour in their lung tissue. The particles of the principal population (size 100-250 nm) dissolved in both alveolar macrophages and type 1 epithelial cells in about two months. Fast and slowly dissolving components of chromium, manganese, and iron were detected within these particles; they obviously represent different chemical compounds. The particles of the minor population (size 5-100 nm) showed no signs of dissolution during three months follow up. Rats exposed to stainless steel fumes generated by MIG had only one particle population in their lung tissue; they were similar to those of the minor population in the MMA/SS fumes and no solubility could be detected within three months.  相似文献   
2.

Background  

Hypertension is one of the major causes of disease burden affecting the Finnish population. Over the last decade, evidence-based care has emerged to complement other approaches to antihypertensive care, often without health economic assessment of its costs and effects. This study looks at the extent to which changes proposed by the 2002 Finnish evidence-based Current Care Guidelines concerning the prevention, diagnosis, and treatment of hypertension (the ACCG scenario) can be considered cost-effective when compared to modelled prior clinical practice (the PCP scenario).  相似文献   
3.
Paternal occupational lead exposure and congenital malformations.   总被引:5,自引:0,他引:5       下载免费PDF全文
STUDY OBJECTIVE--The aim was to investigate whether occupational exposure to lead in fathers is associated with congenital malformation in their children. DESIGN--The study was a retrospective case-control study, nested within the wives of men biologically monitored for inorganic lead. Information on pregnancy outcome was obtained from medical registers. SUBJECTS--Cases were defined as wives with malformed child during 1973-82. Three age matched controls were selected for each case from the wives who had given birth during 1973-1983. The final study population was 27 cases and 57 controls. MEASUREMENTS AND MAIN RESULTS--Paternal lead exposure was assessed with blood lead measurements and data obtained from a questionnaire. The response rate was 67% among the cases and 76% among the controls. The odds ratio (OR) of congenital malformation for paternal lead exposure was increased (OR 2.4, 95% confidence interval 0.9-6.5), although not reaching statistical significance. The odds ratios varied from 1.9 to 3.2, when adjusted for one potential confounding variable at a time. CONCLUSIONS--Because of the small numbers and low participation, this study offers limited support for the hypothesis that paternal lead exposure is associated with congenital malformation. Further epidemiological studies on the reproductive hazards of paternal lead exposure are needed.  相似文献   
4.
Several chromosomal regions are recurrently amplified or deleted in lung tumors, but little is known about the underlying genes, which could be important mediators in tumor formation or progression. In lung cancer, the RB1-CCND1-CDKN2A pathway, involved in the G1-S transition, is damaged in nearly all tumors. In the present study, we localized a novel amplicon in lung tumors to a fragment of less than 0.5 Mb at 12q13.3-q14.1 by using comparative genomic hybridization (CGH) on cDNA microarrays. This approach enabled us to identify 10-15 genes with the most consistent amplifications. Semiquantitative RT-PCR analyses of 13 genes in this region showed that four of them (CDK4, CYP27B1, METTL1, and TSFM) were also highly up-regulated. Immunohistochemical (IHC) analysis of 141 tumor samples on a tissue microarray showed that CDK4 was expressed at a high level in 23% of lung tumors. Six (21.4%) of the tumors with high CDK4 expression (n = 28) were shown by fluorescence in situ hybridization (FISH) to contain the 12q13.3-q14.1 amplification. For CDK4, a positive correlation was found between gene copy number (FISH and CGH array), mRNA expression (RT-PCR), and level of protein expression (IHC). CDK4 expression did not correlate with CDKN2A methylation status. Amplification of CDK4 has been described in other tumor types, but its role in lung cancer remains to be elucidated. Although CDK4 amplification seems to be a relatively rare event (4.3%) in lung tumors, it indicates the significance of the RB1-CCND1 pathway in lung tumorigenesis.  相似文献   
5.
A procedure based on panfungal PCR and multiplex liquid hybridization was developed for the detection of fungi in tissue specimens. The PCR amplified the fungal internal transcribed spacer (ITS) region (ITS1-5.8S rRNA-ITS2). After capture with specific probes, eight common fungal pathogens (Aspergillus flavus, Aspergillus fumigatus, Candida albicans, Candida krusei, Candida glabrata, Candida parapsilosis, Candida tropicalis, and Cryptococcus neoformans) were identified according to the size of the amplification product on an automated sequencer. The nonhybridized products were identified by sequencing. The performance of the procedure was examined with 12 deep-tissue specimens and 8 polypous tissue biopsies from the paranasal sinuses. A detection level of 0.1 to 1 pg of purified DNA (2 to 20 CFU) was achieved. Of the 20 specimens, PCR was positive for 19 (95%), of which 10 (53%) were hybridization positive. In comparison, 12 (60%) of the specimens were positive by direct microscopy, but only 7 (35%) of the specimens showed fungal growth. Sequencing of the nonhybridized amplification products identified an infecting agent in six specimens, and three specimens yielded only sequences of unknown fungal origin. The procedure provides a rapid (within 2 days) detection of common fungal pathogens in tissue specimens, and it is highly versatile for the identification of other fungal pathogens.  相似文献   
6.
OBJECTIVE: We assessed the risk of prostate cancer by exposure to Chlamydia trachomatis. METHOD: Seven hundred thirty eight cases of prostate cancer and 2,271 matched controls were identified from three serum sample banks in Finland, Norway, and Sweden by linkage to the population based cancer registries. RESULTS: A statistically significant inverse association (odds ratio, 0.69; 95% confidence interval, 0.51-0.94) was found. It was consistent by different serotypes and there was a consistent dose-response relationship. CONCLUSION: C. trachomatis infection is not likely to increase the risk of prostate cancer. Whether the inverse relationship is true or due to difficulties in measuring the true exposure in prostatic tissue by serology, confounders or other sources of error remain open.  相似文献   
7.
The effect of a high-fat meal on the oral bioavailability of deramciclane 30 mg tablet was evaluated in 18 healthy male volunteers in a randomised, single dose, two-way crossover study. The drug was administered following an overnight fast or a standardised high-fat breakfast. The plasma concentrations of deramciclane and N-desmethylderamciclane were determined by using a validated HPLC-MS -MS/MS method. An effect of food on the bioavailability was indicated if the 90% confidence interval (CI) for the ratio of geometric means of fed and fasted treatments was not contained in the equivalence limit of 0.8-1.25 for AUC and C(max). The ratios of the mean C(max) and AUC(0-infinity) values of deramciclane were 1.24 (90% CI 1.12-1.38) and 1.31 (90% CI 1.21-1.41) in fed versus fasted subjects, which overlapped but exceeded the equivalence limit. In contrast to the parent compound, the 90% CI of the mean ratios for AUC(0-infinity) and C(max) of N-desmethylderamciclane were within the predefined range. The 24 and 31% increase in C(max) and AUC(0-infinity) of deramciclane, respectively, under fed condition is modest and probably has no clinical significance since it is relatively small compared to the inter-individual variability of these parameters.  相似文献   
8.
Aim: To assess daily practices in paediatric and neonatal ventilatory care in Finland. Methods: All neonatal and paediatric intensive care units in Finland were sent a questionnaire on ventilatory strategies and were offered a 3‐month prospective survey. Results: A total of 96% of units returned the questionnaire, and clinicians agreed on most of the principles of lung‐protective ventilation. Seventeen hospitals (94%) joined the prospective survey. On average, 2.3 new ventilation episodes were started daily, and totally 211 episodes were monitored. Pulmonary problems (64%) were the main cause of treatment in neonates and postoperative care (68%) in older children. Synchronized intermittent mandatory ventilation with pressure support was the primary mode in 42% of episodes. Hypocapnia was observed repeatedly in all units. In adult intensive care units, children often received high oxygen fraction, leading to hyperoxia, and they were frequently sedated with propofol, which is not licensed for that purpose. A large proportion of children had only light sedation or no sedation at all. Despite the different strategies and practices, most episodes resulted in a favourable outcome. Conclusion: Most of the principles of lung‐protective ventilation have been well accepted by clinicians. More attention should be paid to achieving normocapnia and normoxia and to the correct use of sedatives, especially in units that only occasionally provide paediatric ventilation.  相似文献   
9.
Endovascular stenting has matured into a commonly used treatment for peripheral arterial disease (PAD) due to its minimally invasive nature and associated reductions in short-term morbidity and mortality. The mechanical properties of the superelastic Nitinol alloy have played a major role in the explosion of peripheral artery stenting, with modern stents demonstrating reasonable resilience and durability. Yet in the superficial femoral and popliteal arteries, even the newest generation Nitinol stents continue to demonstrate clinical outcomes that leave significant room for improvement. Restenosis and progression of native arterial disease often lead to recurrence of symptoms and reinterventions that increase morbidity and health care expenditures. One of the main factors thought to be associated with stent failure in the femoropopliteal artery (FPA) is the unique and highly dynamic mechanical environment of the lower limb. Clinical and experimental data demonstrate that the FPA undergoes significant deformations with limb flexion. It is hypothesized that the inability of many existing stent designs to conform to these deformations likely plays a role in reconstruction failure, as repetitive movements of the leg and thigh combine with mechanical mismatch between the artery and the stent and result in mechanical damage to both the artery and the stent. In this review we will identify challenges and provide a mechanical perspective of FPA stenting, and then discuss current research directions with promise to provide a better understanding of Nitinol, specific features of stent design, and improved characterization of the biomechanical environment of the FPA to facilitate development of better stents for patients with PAD.  相似文献   
10.
Cell cycle regulators cdc27 and securin participate in control of the mitotic checkpoint and survey the mitotic spindle to maintain chromosomal integrity. This is achieved by their functions in metaphase–anaphase transition, DNA damage repair, enhancement of mitotic arrest and apoptosis. We report on the roles of cdc27 and securin in aneuploidy and prognosis of breast cancer. The study comprises 429 breast cancer patients with up to 22 years of follow‐up. DNA content was determined by image cytometry, and immunopositivity for cdc27 and securin was based on tissue microarrays. An inverse association between cdc27 and securin expression was observed in both image cytometric and immunohistochemical analyses. Low cdc27 and high securin expression identified patients with significant difference in disease outcome. Cdc27 and securin immunoexpression identified patients at risk of early cancer death within five years from diagnosis. In multivariate analysis, the combination of cdc27 and securin immunohistochemistry was the strongest predictor of cancer death after lymph node status. We demonstrate, for the first time in human breast cancer, the prognostic value of cdc27 and securin immunohistochemistry. Cdc27 and securin appear promising biomarkers for applications in predicting disease progression, prognostication of individual patients and potential in anti‐mitotic drug development.  相似文献   
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