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991.
992.
The aim of this study is to validate the Italian version of the Pittsburgh Sleep Quality Index (PSQI), comparing five different groups of individuals (healthy young and elderly, sleep apnoea syndrome patients, depressed patients, individuals with dementia) by both questionnaire scores and polysomnographic measures. Fifty individuals (10 for each group) participated in the study. Each of them filled in the PSQI and slept for two consecutive nights in the sleep laboratory. The PSQI showed an overall reliability coefficient (Cronbach’s α) of 0.835, indicating a high degree of internal consistency. The mean PSQI global score showed significant differences between groups, with an impaired overall quality of sleep in patients’ groups with respect to both the healthy groups. Results also indicated that the best cut-off score (differentiating “good” from “bad” sleepers) is 5. Pittsburgh Sleep Quality Index is a useful, valid and reliable tool for the assessment of sleep quality, with an overall efficiency comparable to the mother language version and differentiate “good” from “bad” sleepers. The Italian version of the questionnaire provides a good and reliable differentiation between normal and pathological groups, with higher scores reported by people characterized by impaired objectively evaluated sleep quality.  相似文献   
993.
A deletion of one of the two copies of the 9-bp tandem repeat sequence (CCCCCTCTA), in the small non-coding/untranslated segment located between the cytochrome oxidase II and lysine tRNA genes of mitochondrial DNA (mtDNA), has previously been used as a polymorphic anthropological marker (MIC9D) for people of Africa and Asia, but it has been rarely reported in Europe. 32 Sicilian patients with syndromic hearing loss, negative for mutations in GJB2 and GJB6 genes, were tested for mtDNA known point mutations associated with syndromic or non-syndromic hearing loss by RFLP and/or direct sequencing. We identified the presence of the MIC9D in homoplasmy in lymphocytes and muscle of three subjects with sensorineural hearing loss and encephalomyopathy, two of these also presented moderate mental retardation. This deletion was absent in 300 Caucasian controls. Although further studies are warranted, our results suggest that the MIC9D polymorphism could have a susceptibility role in Caucasus, such as Sicily population.  相似文献   
994.
A newborn with severe microcephaly and a history of parental consanguinity was referred for cytogenetic analysis and subsequently for genetic evaluation. While a 46,XY karyotype was eventually obtained, premature chromosome condensation was observed. A head MRI confirmed primary microcephaly. This combination of features focused clinical interest on the MCPH1 gene and directed genetic testing by sequence analysis and duplication/deletion studies disclosed a homozygous deletion of exons 1–11 of the MCPH1 gene. This case illustrates a strength of standard cytogenetic evaluation in directing molecular testing to a single target gene in this disorder, allowing much more rapid diagnosis at a substantial cost savings for this family.  相似文献   
995.

OBJECTIVES:

Myeloid-derived suppressor cells contribute to the immunosuppressive microenvironment during tumor development and limit the efficacy of cancer immunotherapy. Identifying myeloid-derived suppressor cells and associated factors is the first step in creating strategies to reverse the suppressive effects of these cells on the immune system.

METHODS:

To induce lung cancer, we administered 2 doses of urethane to BALB/c mice and observed these animals for 120 days. After this period, we evaluated the percentage of myeloid-derived suppressor cells in the blood, lung and bone marrow. The expression of alpha-smooth muscle actin, transforming growth factor-β, Toll-like receptor 2, Toll-like receptor 4, and interleukin-6 was also determined in the lung tissue.

RESULTS:

Myeloid-derived suppressor cells were increased in all evaluated tissues after lung cancer development in association with increased Toll-like receptor 4 expression and decreased interleukin-6 expression in the lung. We observed alpha-smooth muscle actin and transforming growth factor-β expression in lung nodules.

CONCLUSIONS:

We believe that the early diagnosis of cancer through determining the blood levels of myeloid-derived suppressor cells followed by the depletion of these cells should be further investigated as a possible approach for cancer treatment.  相似文献   
996.
997.
998.
Chronic mountain sickness (CMS) is considered to be a loss of ventilatory acclimatization to high altitude (>2500 m) resulting in marked arterial hypoxemia and polycythemia. This case–control study explores the possibility that sleep-disordered breathing (SDB) and associated oxidative stress contribute to the etiology of CMS. Nocturnal respiratory and SaO2SaO2 patterns were measured using standard polysomnography techniques and compared between male high-altitude residents (aged 18–25) with preclinical CMS (excessive erythrocytosis (EE), n = 20) and controls (n = 19). Measures of oxidative stress and antioxidant status included isoprostanes (8-iso-PGF2alpha), superoxide dismutase and ascorbic acid. EE cases had a greater apnea–hypopnea index, a higher frequency of apneas (central and obstructive) and hypopneas during REM sleep, and lower nocturnal SaO2SaO2 compared to controls. 8-iso-PGF2alpha was greater in EE than controls, negatively associated with nocturnal SaO2SaO2, and positively associated with hemoglobin concentration. Mild sleep-disordered breathing and oxidative stress are evident in preclinical CMS, suggesting that the resolution of nocturnal hypoxemia or antioxidant treatment may prevent disease progression.  相似文献   
999.
The aim of this study was to elucidate whether a premaxilla with a supernumerary tooth has additional dental abnormalities. The study does not include premaxillas with a mesiodens, only premaxillas with parasagittally located supernumerary teeth. Radiographs from eight children, followed from 1 year and 5 months to 11 years and 5 months in the municipal dental health service in Denmark, were analyzed. One patient was seen only once. Dental abnormalities recorded included: invaginations on permanent incisors, resorption of roots of incisors, curved roots of incisors, delayed eruption, and delayed formation of roots. The study shows that there are dental abnormalities within the premaxillary region where the supernumerary tooth is located. This indicates that, apart from the supernumerary tooth, a more widespread deviation from normal conditions including tooth malformation, arrested eruption, and root resorption occur within the premaxillary region. The most important outcome of this study is that in the region with a supernumerary tooth the adjacent incisor shows delayed eruption after surgical removal of the supernumerary tooth. The deviations in root morphology, including root resorption, are not limited to patients who have had orthodontic treatment, but patients who did not receive orthodontic treatment also revealed deviations in root morphology. Therefore the treatment outcome can be different from the expected outcome.  相似文献   
1000.
AimTo investigate the root and canal morphology of maxillary and mandibular permanent molar teeth in a Caucasian population by using Cone Beam Computed Tomography (CBCT).MethodsA total of 596 permanent molars were included. The number of roots, the number of canals per root and the root canal configurations according to the method of Vertucci were recorded.ResultsAlmost all of maxillary first molars (95.7%) had three separate roots; however, 40.3% of mesiobuccal roots had two canals (MB2). Of 157 maxillary second molars, 88.5% had three roots. Among the mesiobuccal roots, 15.1% had two canals. The majority of mandibular molars (100% of first molars, 89.4% of second molars) had two separate roots. Most distal roots had a simple type I configuration, whereas mesial roots had more complex canal systems, with more than one canal.ConclusionsCBCT is an efficient method of studying root canal systems.  相似文献   
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