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排序方式: 共有540条查询结果,搜索用时 78 毫秒
91.
Temitope Ayodeji Esan Adeyemi Oluniyi Olusile Elizabeth Obhioneh Oziegbe Christopher I. Udoye Hector O. Olasoji 《Pediatric Dental Journal》2009,19(2):165-173
AimTo determine the causes of tooth loss among Nigerian Children.MethodsThe study was cross sectional. Study population consisted of 557 children aged 1 to 16 years from six tertiary hospitals from each of the six geopolitical zones of the country as well as the Federal Capital Territory (FCT), Abuja. The reasons for extractions of teeth in the children for a period of twelve months were obtained including the age, gender and the type of tooth/teeth extracted.ResultsSeven hundred and fifty teeth were extracted for various reasons during the study period. Majority (55.5%) were extracted because of dental caries, 22.8% for orthodontic reasons, 12.0% for trauma and 6.3% for periodontal disease. More primary teeth (52.7%) were extracted than the permanent teeth in the children. Dental caries was the major cause of extraction of teeth in the south south, south east, north east, north central and the north west zones. While in the south west zone it was malocclusion. In the FCT, periodontal disease was the main reason for extraction of teeth.ConclusionDental caries is still the major cause of tooth loss with the mandibular first permanent molar being the tooth mostly affected. Periodontal disease as a cause of tooth loss in children is on the decrease while there is an increase in orthodontic reasons and trauma. 相似文献
92.
Sharon X. Liang Micheal Pearl Shu Liang Li Xiang Lin Jia Binlie Yang Oluwole Fadare Peter E. Schwartz Setsuko K. Chambers Beihua Kong Wenxin Zheng 《International journal of cancer. Journal international du cancer》2011,128(4):763-770
A comparative study between endometrial serous carcinoma (ESC) and endometrial endometrioid carcinoma (EEC) was performed to determine whether a personal history of breast cancer is a risk factor for ESC in women aged ≤55 yr. Study subjects consisted of 348 women who were diagnosed with ESC and 830 comparison subjects who had EEC. Variables studied included age at diagnosis, a history of breast cancer, tamoxifen therapy, hormonal replacement therapy and smoking history. Overall, 19.4% of women with ESC had a history of breast cancer, which was significantly higher than that of 3% in comparison subjects. Among the study subjects, the incidence of a prior breast cancer was significantly higher in patients who were 55 yr of age or younger (41.5%) than those who were older than 55 yr (16%). The statistical significance of both of the aforementioned comparisons was independent of tamoxifen usage on multivariate analyses. The mean time interval between prior breast cancer and endometrial cancer was 92.5 mo (range 7–240 mo) in the study group and 79 mo (range 7–192 mo) in the comparison group. For the whole cohort and individual subgroups (ESC, EEC, ≤55 yr and >55 yr), a personal history of breast cancer did not adversely affect the patient outcomes, which was largely dependent on standard clinicopathologic parameters such as International Federation of Gynecology and Obstetrics stage, as has previously been demonstrated. These findings suggest that a personal history of breast cancer may be a significant risk factor for the development of ESC in women aged ≤55 yr. Further studies are needed to clarify the relationship between these two cancers in this age group and whether this increased risk is reflective of a genetic predisposition. 相似文献
93.
Fadare O 《Advances in anatomic pathology》2011,18(1):60-74
Pure sarcomas of the uterine corpus are uncommon, constituting less than 3% of all malignancies at this site, and most of them are leiomyosarcomas and endometrial stromal sarcomas. Rare histotypes of homologous sarcomas and heterologous sarcomas are occasionally encountered, and the absence of significant accumulated experience with these histotypes at this location may potentially raise diagnostic and patient management difficulties. In this article, the clinicopathologic attributes of all earlier reported sarcomas of the uterine corpus other than leiomyosarcomas and endometrial stromal sarcomas are summarized. Included are embryonal rhabdomyosarcoma, pleomorphic rhabdomyosarcoma, angiosarcoma, alveolar soft part sarcoma, malignant perivascular epithelioid cell tumors (PEComas), osteosarcoma, chondrosarcoma, liposarcomatous tumors, malignant extrarenal rhabdoid tumors, Ewing sarcoma/primitive neuroectodermal tumor, and other rare histotypes. Embryonal rhabdomyosarcoma (20%), Ewing sarcoma/primitive neuroectodermal tumor (17%), angiosarcoma (14%), and pleomorphic rhabdomyosarcoma (13%) appeared to be more common than the others, although there was no single overwhelmingly prevalent histotype in the group. A subset, including embryonal rhabdomyosarcoma, alveolar soft part sarcoma, and PEComas, peak in the premenopausal years, but most of the others were observed in postmenopausal women. Favorable outcomes have been reported for the patients diagnosed with alveolar soft part sarcoma, and the prognosis for their counterparts with PEComa remains a matter of debate. Multimodal therapeutic approaches to contemporary patients with embryonal rhabdomyosarcomas have resulted in significantly improved outcomes. Unfortunately, most of the other sarcomas have been associated with rapid tumor progression and unfavorable patient outcomes. The differential diagnosis for these sarcomas is often extensive and varies by histotype, but their accurate diagnosis fundamentally requires the careful exclusion of biphasic malignancies. 相似文献
94.
95.
Zuzana Sisková Don Joseph Mahad Carianne Pudney Graham Campbell Mark Cadogan Ayodeji Asuni Vincent O'Connor Victor Hugh Perry 《The American journal of pathology》2010,177(3):1411-1421
Synaptic and dendritic pathology is a well-documented component of prion disease. In common with other neurodegenerative diseases that contain an element of protein misfolding, little is known about the underlying mechanisms of synaptic degeneration. In particular, in prion disease the relationship between synaptic malfunction, degeneration, and mitochondria has been neglected. We investigated a wide range of mitochondrial parameters, including changes in mitochondrial density, inner membrane ultrastructure, functional properties and nature of mitochondrial DNA from hippocampal tissue of mice with prion disease, which have ongoing synaptic pathology. Our results indicate that despite a lack of detectable changes in either mitochondrial density or expression of the mitochondrial proteins, mitochondrial function was impaired when compared with age-matched control animals. We observed changes in mitochondrial inner membrane morphology and a reduction in the cytochrome c oxidase activity relative to a sustained level of mitochondrial proteins such as porin and individual, functionally important subunits of complex II and complex IV. These data support the idea that mitochondrial dysfunction appears to occur due to inhibition or modification of respiratory complex rather than deletions of mitochondrial DNA. Indeed, these changes were seen in the stratum radiatum where synaptic pathology is readily detected, indicating that mitochondrial function is impaired and could potentially contribute to or even initiate the synaptic pathology in prion disease.Mitochondria are vital organelles in all eukaryotic cells and are responsible for the efficient generation of high-energy compounds such as ATP produced by oxidative-phosphorylation system, also called the respiratory chain. The mitochondrial respiratory chain is located in the inner mitochondrial membrane and consists of five complexes (complexes I–V), each consisting of multiple subunits encoded by both nuclear and mitochondrial DNA (mtDNA), except complex II or succinate dehydrogenase (SDH) that is entirely encoded by nuclear DNA.1 Cytochrome c oxidase (COX) or complex IV is the final component of the respiratory chain complex crucial for ATP production and the site of the highest oxygen consumption.2 Neuronal mitochondria display considerable morphological uniformity particularly in terms of the folding of the energy-transducing inner membrane,3 which forms numerous invaginations or cristae. Within the neuron, the synaptic compartment is the site at which demands on mitochondrial functions, such as energy supply and buffering of intracellular Ca2+ are especially significant.4,5 The interdependence of synaptic activity and mitochondrial distribution has been described both at the presynaptic6 and the postsynaptic elements of dendritic spines of living hippocampal neurons.7Several neurodegenerative diseases in which there is accumulation of misfolded proteins, for example Alzheimer’s disease and Parkinson’s disease,8,9,10 are associated with malfunction of both mitochondria and synaptic compartments. Malfunctions of mitochondrial metabolism that lead to reduced ATP production, impaired Ca2+ buffering and generation of reactive oxygen species may contribute to both aging and neurodegenerative disease.11 The inner-membrane structural alterations, in particular numerous dilated or swollen cristae have been consistently implicated in processes associated with apoptosis and as a response to oxidative stress in various neurodegenerative diseases.8,12Prion diseases are fatal transmissible neurodegenerative diseases that affect several species, including humans. The pathological features of prion diseases are extensive neuronal loss, vacuolation, synaptic alterations, and accumulation of a misfolded and protease-resistant form of the prion protein, commonly termed PrPSc.13 There is evidence that in murine prion disease synaptic and dendritic alterations precede neuronal death,14,15,16,17,18 however, the role of the mitochondria in these early synaptic changes has not been investigated during disease evolution.We hypothesized that mitochondrial abnormalities could accompany or perhaps contribute to early synaptic changes in the ME7 model, a murine model that we have previously characterized in some detail.15,17,18 In the present study we demonstrate that the activity of respiratory complex IV is significantly decreased in the hippocampus of diseased animals. This contrasts with the sustained expression of porin, a voltage-gated anion channel located in the outer mitochondrial membrane that is widely used as a mitochondrial marker, and sustained expression of functionally important subunits of complex IV and complex II. Further, morphometric data suggest that mitochondrial numeric density remained unchanged. Interestingly, these changes correlated both temporally and spatially with early loss of Type I (excitatory) synapses in the stratum radiatum. The role of mitochondria is extensively studied as a primary cause of neuronal cell death or as a secondary phenomenon occurring on the way to neuronal death. The current study used tractable, staged and well-characterized prion pathology of the ME7 model that supports the role of an early dysfunction, which thus could be a contributor to disease progression rather than simply a consequence. 相似文献
96.
The study aimed at finding out the clinicopathologic, ophthalmic and visual profiles, management and outcome of mucoceles of the paranasal sinuses in Nigerians. The study was a retrospective review of 20 cases of mucoceles who presented to the ENT clinic and referred to the eye clinic of the University College Hospital Ibadan, Nigeria. These included nine males and 11 females with a male:female ratio of approximately 1:1. Mucoceles commonly involved more than one sinus on the same side. The sinuses commonly involved were the frontoethmoidal sinuses, frontal sinus and maxillary sinuses. The preoperative visual acuity in 16 (80%) patients was 6/4-6/9, three (15%) had between 6/9-6/18, and one (5%) patient was CF ("count fingers") in the affected eyes. The majority (90%) of our patients presented with multiple ophthalmic features; however, proptosis was the most popular and ophthalmic presentation and occurred in 15 (75%) patients. Proptosis was nonaxial in all cases with inferior, lateral or inferolateral displacement. Degree of proptosis ranged from 1-20 mm. Other presentations were squint (leading to diplopia) observed in one (5%) patient and epiphora in another [one (5%)] patient. Poor vision appeared to be the main problem in one (5%) patient, while in another [one (5%)] patient, the affected eye was completely immobilized. One (5%) patient presented with orbital cellulitis. Common radiological findings included classical expansive appearance with loss of the normal scalloping appearance with dehiscence of the wall of the affected sinus as was observed in nine (45%) of our patients. All 20 patients had excision of mucoceles (frontoethmoidectomies). At surgery, 11 (55%) patients had a combination of dehiscence of medial and/or posterior walls, and/or floor of the orbit. Materials evacuated were mucopurulent in 15 (75%) cases, moldy in three (15%) and cheesy in two (10%). Nine (45%) patients had intact walls. Three (15%) patients developed orbital cellulitis as postoperative complication. Postoperatively, proptosis regressed spontaneously within one week of surgery in 17 (85%) patients. By six weeks, all the patients had a complete regression of proptosis and visual acuity returned to preoperative visual acuity level except the patient with preoperative visual acuity of CF. This patient later deteriorated and became NPL (no perception of light) in the affected eye. This was a peculiar case in that operative findings in this patient were suggestive of another coexisting pathology, which was later confirmed to be a non-Hodgkin's lymphoma of the orbit. After two months, only three (15%) reported back for follow-up. The study concluded that proptosis is a common feature of mucoceles of the paranasal sinuses and that visual affectation was rather uncommon. Also whilst mucopurulent materials formed the content of most mucoceles, surgical intervention caused proptosis to regress dramatically. However, due to the high default rate in our study, no categorical statement can be made about recurrence rate of these swellings. 相似文献
97.
98.
Ogegbo OL Dissanyake W Crowder J Asekun O Familoni O Branford-White CJ Annie Bligh SW 《Phytotherapy research : PTR》2012,26(1):127-135
Metabonomics is an important tool in understanding the toxicological or therapeutic effects of interventions by analysing metabolic profiles and interpreting complex multi‐dimensional spectroscopic/spectrometric data using multivariate data analysis. The objectives of this study were to evaluate the metabolic changes following a short‐term 5 day soya milk intervention, and to investigate factors that influence soy‐phytoestrogen metabolism focused on Africans based in either UK or Nigeria. 1H‐NMR metabonomics was applied to analyse urine samples collected at four phases I–IV (pre, days 3 and 5, and post) of the soy‐intervention from African volunteers (n = 40 in total). Individual proton NMR spectra were visually and statistically assessed using multivariate analyses (MVA): principal component analysis (PCA) and (orthogonal‐) partial‐least square–discriminant analysis ((O‐) PLS‐DA). In addition, 22 endogenous metabolites were quantified using a Chenomx NMR suite. The results showed the levels of analysed endogenous metabolites (creatinine adjusted) present ranged from 4 µ m to 12 m m with large inter‐subject variances in acetate, acetone, lactate and trimethylamine. The MVA results showed high inter‐individuality and sampling variances based on PCA score plots, and demonstrated soy metabolism to be significantly influenced by location and gender by both PLS‐DA and O‐PLS‐DA. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
99.
Oziegbe EO Adekoya-Sofowora C Esan TA Owotade FJ 《The Journal of clinical pediatric dentistry》2008,32(4):341-345
The eruption chronology of the primary dentition has been studied in some populations, however; only few studies from Nigeria and other African countries have been reported. OBJECTIVE: To determine the appropriate reference standard for eruption of primary teeth in Nigerian children. SUBJECTS AND METHODS: A cross sectional study consisting of 1,013 clinically healthy babies, infants and preschool children between the ages of 4 to 36 months from the community health centers immunization clinics in Ife Central and Ife East Local Government Areas. RESULTS: Boys erupted primary teeth earlier than girls in both arches except the first molars. However girls had a shorter duration of eruption (from the first tooth to erupt to the last tooth to erupt) when compared to boys. In addition, boys had a systematic tendency for earlier eruption on the left side.CONCLUSION: Within the limitations of this study, a baseline data for eruption of primary teeth among Nigerian children has been established. Nigerian children experienced an earlier eruption of primary teeth when compared to their Arabian and American counterparts and a later eruption when compared to children from Iceland. 相似文献
100.