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排序方式: 共有711条查询结果,搜索用时 15 毫秒
31.
Eija Peltonen Pirjo-Liisa Lukinmaa Carin Sahlberg Anna-Maija Partanen Anu Kiukkonen Satu Alaluusua 《Toxicological sciences》2006,92(1):279-285
Clinical studies suggest that maternal smoking during pregnancy can reduce the crown size of the child's teeth. Delayed dental age compared with chronological age has also been reported in children whose parents smoke. Among the main components of tobacco smoke are nonhalogenated polycyclic aromatic hydrocarbons (PAHs), many of which are highly toxic. Humans are exposed to PAH compounds mainly via tobacco smoke and diet. The aim of our study was to investigate the effect of PAHs on tooth formation and the function of tooth-forming cells. We exposed mouse (NMRI) E18 mandibular first and second molar explants to 7,12-dimethylbenz[a]anthracene (DMBA), a toxic PAH compound, in organ culture for 7 or 12 days. DMBA concentrations used were 0.1, 0.5, 1, and 2 microM. The mesiodistal width of each first molar (12-day culture) was measured in stereomicroscopic images, and the teeth were analysed histologically. DMBA exposure significantly reduced the mesiodistal width of the first molars. DMBA impaired or delayed amelogenesis and dentinogenesis in both molars at the lowest concentration of 0.1 microM. DMBA affected enamel formation more severely than dentin formation and occasionally prevented amelogenesis completely. Elongation and polarization of ameloblasts were impaired, and blood vessel architecture of the dental papilla (future pulp) was altered. Cusps were thin and sharp. In line with the finding that maternal smoking during pregnancy has an adverse effect on child's tooth development, this study shows the toxic influence of PAHs on tooth development in vitro. 相似文献
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Kattainen E Sintonen H Kettunen R Meriläinen P 《International journal of technology assessment in health care》2005,21(2):172-179
OBJECTIVES: The aim of the study was to compare the health-related quality of life (HRQoL) of patients undergoing coronary artery bypass grafting (CABG) or percutaneous transluminal coronary angioplasty (PTCA) before the interventions and 6 and 12 months afterward, and to compare their HRQoL also with that of the general population. METHODS: The sample (n = 615) consisted of consecutive coronary artery disease patients treated with elective CABG (n=432) or PTCA (n=183). The baseline data before the treatments were collected by structured interview, the follow-up data mainly by mailed self-administered questionnaires. HRQoL was measured by the 15D. For comparisons, the groups were standardized for differences in socioeconomic and clinical characteristics with a regression analysis. RESULTS: At baseline, the average 15D scores of the patient groups were 0.752 (95 percent confidence interval [CI], 0.743-0.761) in CABG and 0.730 (95 percent CI, 0.716-0.744) in PTCA. After standardization, the difference between the groups was statistically significant but not clinically important. These scores were significantly worse (statistically and clinically) than the score of 0.883 (95 percent CI, 0.871-0.879) in the general population sample matched with the gender and age distribution of the patients. By 6 months, the CABG and PTCA patients had experienced a statistically significant and clinically important improvement to 0.858 (95 percent CI, 0.844-0.872) and 0.824 (95 percent CI, 0.806-0.842), respectively. No significant change took place in either group from 6 to 12 months. CONCLUSIONS: Both CABG and PTCA produces an approximately similar, clinically important improvement in HRQoL in 1-year follow-up. 相似文献
34.
Lehtonen-Smeds EM Mayranpaa M Lindsberg PJ Soinne L Saimanen E Jarvinen AA Salonen O Carpén O Lassila R Sarna S Kaste M Kovanen PT 《Cerebrovascular diseases (Basel, Switzerland)》2005,19(5):291-301
OBJECTIVE: Increased numbers of mast cells (MCs) are present in ruptured coronary plaques, suggesting to play a role in acute coronary syndromes. We evaluated the distribution densities of MCs, macrophages and T cells in carotid plaques and correlated these findings to stroke risk factors as well as history of stroke or TIA. METHODS AND RESULTS: Seventy-eight carotid samples from 75 patients (16 plaques from asymptomatic patients and 62 from patients with recent ischemic symptoms) undergoing carotid endarterectomy with an internal carotid stenosis >70% that were immunostained and quantified for MCs, macrophages and T cells. The MC distribution density showed positive correlation with the degree of carotid stenosis (p = 0.012), serum levels of total cholesterol (p = 0.021), LDL cholesterol (p = 0.013) and triglycerides (p = 0.005), and an inverse correlation with serum HDL cholesterol levels (p = 0.001). The average MC density (p = 0.023), but not the macrophage (p = 0.58) or T cell (p = 0.74) density, was higher in the symptomatic than in the asymptomatic patients. In a comparison of plaques ipsilateral and contralateral to the thromboembolic event, the densities of the three types of inflammatory cells were similar. CONCLUSIONS: Increased MC distribution density is associated with an atherogenic serum lipid profile, high-grade carotid artery stenosis and symptomatic carotid artery disease. These findings suggest a potential involvement of MCs in the pathophysiology of carotid artery stenosis. 相似文献
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36.
Lundbom JO Vuori KE Gaily EK Granström RI Blomstedt GC Häkkinen AM Heikkinen SM Lundbom NM 《AJNR. American journal of neuroradiology》2005,26(5):1072-1077
BACKGROUND AND PURPOSE: In MR spectroscopic imaging (MRSI), the volume-selection profiles of metabolites differ from each other. These differences cause variations in metabolite intensities, which are particularly prominent when the hippocampi are evaluated. We hypothesize that the errors arising from these effects cause notable artifact when temporal lobe epilepsy (TLE) is lateralized with MRSI. METHODS: We examined a metabolite phantom, control subjects, and patients with TLE by using MRSI. We calculated the error arising from the different volume-selection profiles of metabolites in vitro and evaluated this correction in the examination of the control subjects and in the lateralization of epilepsy in the patients. RESULTS: Without a correction, a considerable error in the metabolite content existed, even deep inside the spectroscopic volume of interest. The result was false asymmetry (P < .008) in the hippocampi of control subjects. Among the 11 patients, TLE was correctly lateralized in three only after the correction was made, and in one, TLE was incorrectly lateralized. CONCLUSION: The volume-selection profiles of N-acetylaspartate, choline, and creatine differ enough to cause a significant error, even in the metabolite ratios, when patients with TLE are examined with MRSI. We propose a simple phantom method to correct for this error without a need to modify the pulse sequence. 相似文献
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38.
Leidenius M Krogerus L Tukiainen E von Smitten K 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2004,112(4-5):264-270
We aimed to compare the accuracy of axillary staging in breast cancer between sentinel node biopsy (SNB) and axillary lymph node dissection (ALND). The prevalence of axillary metastases was studied in 166 breast cancer patients with SNB and pair-matched control patients with ALND. The matching factors included age of the patient and grade, histological type and histological size of the tumour. There were 37% of patients with axillary metastases in the SNB group and 31% in the ALND group. Altogether, 57 pairs were discordant in relation to axillary metastases. In 34 discordant pairs the SNB patient and in 23 the ALND patient had axillary metastases, p=ns. Among the 36 discordant pairs with invasive ductal carcinoma (IDC), axillary metastases were detected as often in the SNB and the ALND patients. In the 21 discordant pairs with other histological types, the SNB patient had axillary metastases in 16 pairs and the ALND patient in 5 pairs, p<0.03. SNB seems to be as accurate a method for axillary staging as ALND. However, SNB generated no upstaging effect in IDC, only in other histological tumour types. 相似文献
39.
In July 2001, an outbreak of gastroenteritis occurred in Helsinki among children and adults after bathing in an outdoor wading pool. The epidemiological survey revealed that at least 242 persons were affected. Microbiological testing of both patient stool samples and of the pool water revealed the presence of two different gastroenteritis viruses: a norovirus (NV) and an astrovirus. Amplicon sequencing of the NV samples showed nucleotide sequence identity between the virus from patients and the water. After changing the pool water and the sand at the bottom of the pool followed by shock chlorination, no virus could be detected in the water. However, NV was continuously detected in the water outlet well as much as 8 months after the incident. Here we show how molecular methods aided in tracing the source of the epidemic and in finding the causative pathogens both in patients and in the environment. 相似文献
40.
High-resolution genomic and expression profiling reveals 105 putative amplification target genes in pancreatic cancer 总被引:2,自引:0,他引:2
Mahlamäki EH Kauraniemi P Monni O Wolf M Hautaniemi S Kallioniemi A 《Neoplasia (New York, N.Y.)》2004,6(5):432-439
Comparative genomic hybridization (CGH) studies have provided a wealth of information on common copy number aberrations in pancreatic cancer, but the genes affected by these aberrations are largely unknown. To identify putative amplification target genes in pancreatic cancer, we performed a parallel copy number and expression survey in 13 pancreatic cancer cell lines using a 12,232-clone cDNA microarray, providing an average resolution of 300 kb throughout the human genome. CGH on cDNA microarray allowed highly accurate mapping of copy number increases and resulted in identification of 24 independent amplicons, ranging in size from 130 kb to 11 Mb. Statistical evaluation of gene copy number and expression data across all 13 cell lines revealed a set of 105 genes whose elevated expression levels were directly attributable to increased copy number. These included genes previously reported to be amplified in cancer as well as several novel targets for copy number alterations, such as p21-activated kinase 4 (PAK4), which was previously shown to be involved in cell migration, cell adhesion, and anchorage-independent growth. In conclusion, our results implicate a set of 105 genes that is likely to be actively involved in the development and progression of pancreatic cancer. 相似文献