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31.
Expression of the cyclin-dependent kinase inhibitors (CKIs) has been linked to the inhibition of cellular proliferation and the induction of differentiation. Based on structure function analysis, two distinct families of CDKIs, the INK4 and the Cip/Kip family have been identified. The INK4 family member p16(Ink4), and the Cip/Kip protein p27(Kip1) have been implicated in normal development of the CNS and cerebellum. Recent studies have suggested a functional inter-dependence between the CKI and the abundance of cyclin D1 in orchestrating growth factor-induced cellular proliferation. The neonatal rat cerebellum undergoes proliferative growth and differentiation, localized to distinct topographical regions and cell types. The cell type and the temporal profile of CKI expression during postnatal cerebellar development had not been described. The current studies determined the specific cerebellar cell types in which the CKIs were expressed during post natal development by co-staining for cell-type specific markers. p16(Ink4a) and p27(Kip1) immunostaining was identified in both neurons and glial cells, increasing progressively between postnatal days 6 to 13 into adulthood. By contrast, neuronal and glial cell p21(Cip1) staining was prominent at days 6-11 and decreased thereafter. Cyclin D1 was expressed in the proliferating external granular cells, with occassional staining in the molecular, and internal granular layers. Dual immunostaining demonstrated cyclin D1 within cells expressing CKI (p16(Ink4a), p21(Cip1),p27(Kip1)). Cerebellar cellular growth arrest, induced by protein-calorie malnutrition, inhibited cyclin D1 protein levels without affecting CKI immunostaining suggesting CKI do not mediate the developmental arrest. These results demonstrate that the CKIs are induced by differentiation cues in specific cell types with distinct kinetics in the developing cerebellum in vivo.  相似文献   
32.
The treatment of lateral clavicle fractures   总被引:4,自引:0,他引:4  
Webber MC  Haines JF 《Injury》2000,31(3):175-179
This study assesses the results of surgical treatment of 15 displaced Neer type II fractures of the lateral clavicle in 15 patients, which occurred between November 1988 and March 1995 and which were followed up for a mean period of 4.6 years (range 2-9 years). The patients fell into two groups, one 'acute group' and one 'non-union' group.Patients treated initially by a non-operative approach had suffered prolonged morbidity and time off work prior to and after surgery. The ultimate result was good. The fixation used was a Dacron arterial graft as a sling around the clavicle and coracoid process. Delayed (non-union) cases were augmented with bone graft and inter-fragmentary screw fixation. All fractures eventually united.We question the place of prolonged non-operative management in the treatment of displaced Neer type II fractures of the lateral clavicle.  相似文献   
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34.
There is limited research on the intake of non-nutritive sweeteners (NNS) among preschool-aged children. Canada’s Food Guide suggests limiting intake of NNS for all population groups and Health Canada recommends that young children (<2 years) avoid consuming beverages containing NNS. The aim of this study was to investigate the frequency and type of non-nutritive sweetener (NNS) intake in preschool-aged children participating in the Guelph Family Health Study pilots. Parents (n = 78 families) completed 3-day food records (n = 112 children; n = 55 females, n = 57 males; 3.6 years ± 1.3). Nineteen children (17%) reported consumption of foods or beverages containing NNS. Food sources with NNS included: freezies, oral nutritional supplements, flavored water, carbonated drinks, sugar free jam and protein powder. The majority of NNS contained in these foods were identified as stevia leaf extract, acesulfame K, sucralose, monk fruit extract and aspartame. Future research should continue to study NNS intake patterns longitudinally in children and examine the association of NNS intake with diet quality and health outcomes.  相似文献   
35.
The fetal femoral length and biparietal diameter were measured by ultrasound on 1657 occasions in 1289 singleton pregnancies between 12 and 41 weeks' gestation. Mean values for fetal femoral length were significantly lower than those demonstrated in previous studies, with the difference becoming greater approaching term. Three hundred twenty-two measurements of fetal femoral length were made on 57 patients with twin pregnancies, with no significant difference noted between the means of these recordings and the means of the singleton pregnancies.  相似文献   
36.
目的探讨宫颈液基细胞学及阴道镜检查在北京市社区妇女宫颈病变筛查中的临床意义。方法2006年6月至2007年6月对北京市展览路社区的795位20~54岁有性生活的妇女进行筛查。筛查对象接受妇科检查时,留取宫颈超柏氏薄层液基细胞学检测标本,并对宫颈细胞学异常者行阴道镜检查及活组织检查。结果宫颈细胞学阳性[≥ASC-US(不能明确意义的不典型鳞状细胞)]45例,占5.7%(45/795)。其中ASC-US33例,占73.3%(33/45);低度鳞状上皮内病变8例;高度鳞状上皮内病变3例;不典型腺细胞1例。细胞学阴性750例,占94.3%(750/795)。宫颈细胞学阳性的45例中,5例拒绝行阴道镜检查,占11.1%(5/45)。在行阴道镜活组织病理检查的40例中,慢性宫颈炎11例(27.5%);宫颈湿疣14例(35.0%);宫颈上皮内瘤样病变(CIN)1为7例(17.5%);CIN2为3例(7.5%);CIN3为4例(10.0%);早期浸润癌1例(2.5%)。细胞学阴性的750例中,宫颈湿疣2例(0.3%);CIN1为5例(0.7%);宫颈低级别腺上皮内病变1例(0.1%)。宫颈液基细胞学筛查CIN1及以上宫颈病变和宫颈癌的敏感度71.4%,特异度94.2%,阳性预测值37.5%,阴性预测值99.2%;筛查CIN2及以上宫颈病变和宫颈癌的敏感度100.0%,特异度96.0%,阳性预测值20.5%,阴性预测值100.0%。结论应重视并及时进行北京市社区人群宫颈病变的早期筛查,薄层液基细胞学结合阴道镜活组织检查及病理学检查,对提高早期宫颈癌筛查的准确性效果明显。  相似文献   
37.
Evidence-based neurosurgery   总被引:3,自引:0,他引:3  
Haines SJ 《Neurosurgery》2003,52(1):36-47; discussion 47
OBJECTIVE: The evidence-based medicine movement is gaining influence in many medical specialties. Although many think that clinical medicine always has been based on evidence, the discipline of evidence-based medicine places particular emphasis on a defined set of principles of critical analysis of individual research reports, methodologically rigorous synthesis of multiple reports, and the collection and dissemination of evidence repositories that allow rapid application of evidence in practice. This article provides a selective introduction to the discipline of evidence-based medicine as it applies to neurological surgery. METHODS: The vast literature on evidence-based medicine has been reviewed selectively to identify resources that are readable, accessible, and relevant to neurosurgery. RESULTS: The history, concepts, and techniques of evidence-based medicine are presented in brief, and educational and methodological resources, as well as evidence repositories, are introduced. CONCLUSION: The techniques of evidence-based medicine are relevant to neurological surgery. There is a relatively large repository of critically analyzed and summarized evidence that is useful to the neurosurgical practitioner. Familiarity with these techniques and repositories can help the neurosurgeon bring the best available evidence to bear on the care of individual patients.  相似文献   
38.
Computed tomographic detection of nonbeta pancreatic islet cell tumors   总被引:6,自引:0,他引:6  
  相似文献   
39.
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia.  相似文献   
40.
Conditioned medium (CM) obtained from a human hepatoma cell line, SK- HEP-1, contains colony-stimulating factors (CSFs) active on murine and human bone marrow-derived granulocyte and macrophage colony-forming units (CFU-GM) and a factor capable of inducing granulocyte-macrophage differentiation (GM-DF) of murine myelomonocytic leukemic cells WEHI- 3B(D+) and human promyelocytic leukemic cells HL-60 when assayed in semisolid agar cultures. The human active granulocyte-macrophage colony- stimulating factor (GM-CSF) for day 7 CFU-GM and the GM-DF for WEHI- 3B(D+) and for HL-60 are not separable by acrylamide agarose column chromatography, eluting at an apparent molecular weight between 20,000 and 35,000 daltons, or by isoelectric focusing (isoelectric point, pH 5.4). In addition, SK-HEP-1 CM contains erythroid burst-promoting activity (BPA) and a factor that promotes the growth of human mixed colonies. SK-HEP-1 cells, which grow as an adherent monolayer, appear not to be endothelial or monocytic in origin since by immunofluorescent staining they are negative for Ia (HLA-DR), monocyte antigen 1 and 2, lysozyme, and factor VIII-related antigen. Positive immunofluorescent staining for keratin and fibronectin suggests the possibility that SK- HEP-1 is an epithelial cell line. Constitutive production of GM-DF as well as other hematopoietic activities including GM-CSF, erythroid BPA, and an activity that promotes the growth of human mixed colony progenitors by a human epithelial tumor cell line, SK-HEP-1, suggests that this cell line is a valuable resource for both large-scale production of these factors and the cloning of the gene(s) that code for these regulators.  相似文献   
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