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81.
Stromal extracellular matrix (ECM) components are thought to play an important role in regulating invasion of human gliomas. Macrophages and microglial cells may heavily influence the integrity of the extracellular compartment of gliomas, and the affected ECM may play a key role in regulating migratory activity of both tumor cells and macrophages/microglia. The aim of this investigation was to study immunohistochemically the expression patterns of four ECM components: fibronectin, laminin, collagen IV, and tenascin (TN) in human gliomas, with special attention to TN. Our main goal was to study the possible correlation between TN expression and macrophagic/microglial infiltration in gliomas. Altogether, 90 gliomas were studied. Tumors included 46 glioblastomas, 19 anaplastic gliomas, 22 low grade gliomas, and 3 pilocytic astrocytomas. Vascular TN prevailed in perinecrotic areas of glioblastomas, whereas interstitial TN was more often expressed distant from necrosis and in the ECM of anaplastic and low grade gliomas. Double staining with CD68 and anti-TN antibodies showed that macrophagic/microglial density was significantly higher in TN-positive areas of most of the glioblastomas and anaplastic gliomas, whereas microglial percentage from total number of CD68-positive cells was in most of the cases significantly higher in TN-negative areas. In addition, we saw a morphologically spatial correlation between higher densities of macrophagic/microglial infiltration and TN expression in perinecrotic areas in glioblastomas. Attachment of macrophages to TN-positive basement membrane zones of newly formed stromal blood vessels was evident. On the basis of our results, we conclude that TN may play a crucial role in regulating trafficking of cells of monocyte lineage in human gliomas. 相似文献
82.
Summary
Introduction Schwannomas are most often found in association with the eighth cranial nerve, but may also arise from any other cranial nerve.
They are rarely found in an intra-parenchymal location. Unusual locations for intracranial schwannomas have also been reported
in association with neurofibromatosis.
Clinical presentation A 23-year-old male without von Recklinghausen’s disease presented with intermittent dizziness and difficulty swallowing. Past
medical history was significant for a motor vehicle accident (MVA) without loss of consciousness 6 months prior. Magnetic
resonance imaging revealed a large tentorial-based tumor. At surgery the origin of the tumor was clearly the tentorium, and
while the trigeminal nerve was displaced, it easily separated from the mass. There was no attachment to any other cranial
nerve in the immediate vicinity and postoperative cranial nerve examination was unremarkable. Pathological review was consistent
with schwannoma.
Conclusion While there are few reported cases of tentorial-based schwannoma, these tumors have been noted in unusual locations within
the intracranial vault, and clinicians should be aware of this diversity of origin. 相似文献
83.
Grahn Kronhed AC Knutsson I Löfman O Timpka T Toss G Möller M 《Scandinavian journal of public health》2004,32(5):333-339
AIMS: The aim of this study was to investigate the associations between forearm bone mineral density (BMD), calcaneal stiffness, and physical activity levels in a normal population using different non-invasive methods. METHODS: The participants were invited to undergo bone measurements using single photon absorptiometry of the forearm and quantitative ultrasound (QUS) of the calcaneal bone, and also to complete a questionnaire. Physical activity levels were designated low, moderate, and high in the question on leisure-time activity. RESULTS: There were 956 participants included in the present study. Forearm BMD in the eighth age decade was 0.40 g/cm2 (95% CI 0.33-0.46 g/cm2) lower than in the third decade among women and 0.28 g/cm2 (95% CI 0.18-0.37 g/cm2) lower among men. The differences in calcaneal stiffness between the same age decades were 22.4 (95% CI 17.5-27.4) among women and 15.8 (95% CI 8.0-23.5) among men. The correlation between forearm BMD and calcaneal stiffness was 0.58 (95% CI 0.52-0.64) in women and 0.34 (95% CI 0.25-0.42) in men. Reported moderate and high leisure-time activity levels in both genders were associated with higher calcaneal stiffness but not with forearm BMD. Conclusions: The QUS may be used to measure the effect of present physical activity levels on calcaneal bone at the population level. Further longitudinal studies are warranted in order to determine the most appropriate non-invasive method in population-based studies. 相似文献
84.
85.
Today, nurses from many disciplines are expected to provide nursing care to refugees severely traumatized in war and conflict. The general aim of this study was to explore the long-term impact of torture on the mental health of war-wounded refugees. The study group consisted of 22 tortured and 22 nontortured male refugees who had been injured in war. Standardized interview schedules, exploring different background characteristics, and three instruments for assessment of mental health were used: the Hopkins Symptom Checklist, the Post Traumatic Symptom Scale and a well-being scale. The prevalence of psychiatric symptoms was high in both groups. However, there were no significant differences in mental health between the tortured and the nontortured refugees. The patterns of associations between background characteristics and mental health were different in the two groups. The strongest associations with lower level of mental health were higher education in the tortured group and unemployment in the nontortured group. Methodological difficulties in research on sequelae of prolonged traumatization remain. Further studies within the caring sciences can broaden the present understanding of the impact of torture and other war traumas. 相似文献
86.
PURPOSE: Bandy, with a century-long tradition in northern Europe, is a winter team-sport similar to ice hockey. To investigate the occurrence of injuries during competitive youth bandy games, injury incidence, injury types, and age-related risks were analyzed for one youth league season. METHODS: The National Athletic Injury/Illness Reporting System (NAIRS) definition of sports injury was used for the injury registration. All 416 games during the 1999-2000 season in the Swedish southeastern youth bandy league were included in the study. Primary data was collected by a questionnaire and completed by the team coaches after each game. At the end of the season, physician interviews with each team coach were performed to assure that no injuries had been missed as well as to ascertain whether there was any remaining disability. RESULTS: In total, 2.0 injuries (95% confidence interval 1.2-2.9 injuries) per 1000 player game hours were recorded. Sixty-eight percent of the injuries caused the injured player to be absent from bandy play for more than a week. Collision was the most common cause of injury (36%), and contusion was the most common injury type (41%). The injury incidence in the leagues for older players (Youth 14 -Youth 16) was slightly higher than in the leagues for the younger players (Youth 12 -Youth 13), while participation by under-aged players in games organized for older players led to an almost four-fold increase of injury risk. For severe injuries, the mean rehabilitation time away from bandy practice or competition was 27 d (range 8-56 d). CONCLUSION: The overall injury incidence during youth bandy games is low, but the injuries that occur cause extensive absences from the only four months long bandy season. From a public health perspective, bandy can be recommended for consideration when physical exercise is to be promoted among school-age children in countries with a winter climate. 相似文献
87.
Y-chromosome Lineages from Portugal, Madeira and Açores Record Elements of Sephardim and Berber Ancestry 总被引:2,自引:0,他引:2
Rita Gonçalves Ana Freitas Marta Branco Alexandra Rosa Ana T. Fernandes Lev A. Zhivotovsky Peter A. Underhill Toomas Kivisild António Brehm 《Annals of human genetics》2005,69(4):443-454
A total of 553 Y‐chromosomes were analyzed from mainland Portugal and the North Atlantic Archipelagos of Açores and Madeira, in order to characterize the genetic composition of their male gene pool. A large majority (78–83% of each population) of the male lineages could be classified as belonging to three basic Y chromosomal haplogroups, R1b, J, and E3b. While R1b, accounting for more than half of the lineages in any of the Portuguese sub‐populations, is a characteristic marker of many different West European populations, haplogroups J and E3b consist of lineages that are typical of the circum‐Mediterranean region or even East Africa. The highly diverse haplogroup E3b in Portuguese likely combines sub‐clades of distinct origins. The present composition of the Y chromosomes in Portugal in this haplogroup likely reflects a pre‐Arab component shared with North African populations or testifies, at least in part, to the influence of Sephardic Jews. In contrast to the marginally low sub‐Saharan African Y chromosome component in Portuguese, such lineages have been detected at a moderately high frequency in our previous survey of mtDNA from the same samples, indicating the presence of sex‐related gene flow, most likely mediated by the Atlantic slave trade. 相似文献
88.
Babalini C Martínez-Labarga C Tolk HV Kivisild T Giampaolo R Tarsi T Contini I Barać L Janićijević B Martinović Klarić I Pericić M Sujoldzić A Villems R Biondi G Rudan P Rickards O 《European journal of human genetics : EJHG》2005,13(8):902-912
This study examines the mitochondrial DNA (mtDNA) diversity of the Croatian-speaking minority of Molise and evaluates its potential genetic relatedness to the neighbouring Italian groups and the Croatian parental population. Intermatch, genetic distance, and admixture analyses highlighted the genetic similarity between the Croatians of Molise and the neighbouring Italian populations and demonstrated that the Croatian-Italian ethnic minority presents features lying between Croatians and Italians. This finding was confirmed by a phylogeographic approach, which revealed both the prevalence of Croatian and the penetrance of Italian maternal lineages in the Croatian community of Molise. These results suggest that there was no reproductive isolation between the two geographically proximate, yet culturally distinct populations living in Italy. The gene flow between the Croatian-Italians and the surrounding Italian populations indicate, therefore, that ethnic consciousness has not created reproductive barriers and that the Croatian-speaking minority of Molise does not represent a reproductively isolated entity. 相似文献
89.
MtDNA Profile of West Africa Guineans: Towards a Better Understanding of the Senegambia Region 总被引:1,自引:1,他引:1
Alexandra Rosa António Brehm Toomas Kivisild Ene Metspalu Richard Villems 《Annals of human genetics》2004,68(4):340-352
The matrilineal genetic composition of 372 samples from the Republic of Guiné‐Bissau (West African coast) was studied using RFLPs and partial sequencing of the mtDNA control and coding region. The majority of the mtDNA lineages of Guineans (94%) belong to West African specific sub‐clusters of L0‐L3 haplogroups. A new L3 sub‐cluster (L3h) that is found in both eastern and western Africa is present at moderately low frequencies in Guinean populations. A non‐random distribution of haplogroups U5 in the Fula group, the U6 among the “Brame” linguistic family and M1 in the Balanta‐Djola group, suggests a correlation between the genetic and linguistic affiliation of Guinean populations. The presence of M1 in Balanta populations supports the earlier suggestion of their Sudanese origin. Haplogroups U5 and U6, on the other hand, were found to be restricted to populations that are thought to represent the descendants of a southern expansion of Berbers. Particular haplotypes, found almost exclusively in East‐African populations, were found in some ethnic groups with an oral tradition claiming Sudanese origin. 相似文献
90.