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991.
992.

Background  

Acetabular revision is probably the most difficult aspect of hip reconstructive surgery. Although the majority of acetabular revisions can be performed using an uncemented hemispherical acetabular device with ancillary fixation, patients with severe acetabular deficiencies and poor bone quality require more complex alternatives for revision. The limitations of traditional cementless acetabular implants has promoted the development of improved methods of fixation and revision techniques. Highly porous metals have been introduced for clinical use in arthroplasty surgery over the last decade. Their higher porosity and surface friction are ideal for acetabular revision, optimising biological fixation. The use of trabecular metal cups in acetabular revision has yielded excellent clinical results.  相似文献   
993.
The surface electromyography (sEMG) signal separation and decphompositions has always been an interesting research topic in the field of rehabilitation and medical research. Subtle myoelectric control is an advanced technique concerned with the detection, processing, classification, and application of myoelectric signals to control human-assisting robots or rehabilitation devices. This paper reviews recent research and development in independent component analysis and Fractal dimensional analysis for sEMG pattern recognition, and presents state-of-the-art achievements in terms of their type, structure, and potential application. Directions for future research are also briefly outlined.  相似文献   
994.
In an attempt to develop effective and safer analgesic anti-inflammatory agents, nine compounds belonging to 4-[1-oxo-3-(substituted aryl)-2-propenyl]-3-(4-methoxyphenyl) sydnones, containing the structural features of mesoionic sydnone and styrylketone, have been designed and synthesized by condensing 4-acetyl-3-(4-methoxyphenyl) sydnone with various substituted aryl aldehydes and characterized by spectral studies. They have been tested for analgesic activity by acetic acid induced writhing in mice and for anti-inflammatory activity by carrageenan induced rat paw edema at 100 mg/kg body weight p.o. The compounds containing furyl and chloro substituents showed highly significant analgesic effect, while those with dimethylamino, chloro and nitro substituents exhibited highly significant anti-inflammatory effect at the end of 3 h. The compounds that showed good analgesic and anti-inflammatory activities were evaluated for ulcerogenicity in rats to assess their gastric side effects at 100 mg/kg body weight p.o. They were found to be less ulcerogenic than the standard drug.  相似文献   
995.
The present paper describes development of a polysaccharide based compression coated tablets of secnidazole for colon delivery. Core tablet containing secnidazole was compression coated with various proportions of guar gum, xanthan gum and chitosan, either alone or in combinations. Drug release studies were performed in simulated gastric fluid (SGF) for 2 h followed by simulated intestinal fluid (SIF, pH 7.4) up to 24 h. Secnidazole release from the prepared formulations was dependent on the type and concentration of polymer used in the formulation. Tablets coating containing either guar gum or xanthan gum showed ~30-40% drug release in 8 h. Further, in vitro dissolution studies of selected formulations performed in the dissolution media with rat caecal contents showed 54.48±0.24 - 60.42±0.16% of drug release. Formulations with single polymer in coating layer were unsuitable for targeting secnidazole release to colon region. Combination of chitosan with guar gum or xanthan gum exhibited control over secnidazole release.  相似文献   
996.
A number of chemotherapy drugs are well known to cause various histopathologic patterns of lung injury. The incidence of chemotherapy-induced infiltrative pneumonitis is rare and the diagnosis is difficult due to the nonspecific clinical and radiological presentations. However, it can cause significant morbidity and mortality in cancer patients. There is no consensus on the treatment of this adverse event, but prompt diagnosis and intervention is important as fatal outcomes have been reported. We present five cases of chemotherapy-induced infiltrative pneumonitis in breast cancer patients involving docetaxel, paclitaxel, gemcitabine and cyclophosphamide.  相似文献   
997.
Whole genome sequencing of personal genomes has revealed a large repertoire of genomic variations and has provided a rich template for identification of common and rare variants in genomes in addition to understanding the genetic basis of diseases. The widespread application of personal genome sequencing in clinical settings for predictive and preventive medicine has been limited due to the lack of comprehensive computational analysis pipelines. We have used next-generation sequencing technology to sequence the whole genome of a self-declared healthy male of Indian origin. We have generated around 28X of the reference human genome with over 99% coverage. Analysis revealed over 3 million single nucleotide variations and about 490,000 small insertion-deletion events including several novel variants. Using this dataset as a template, we designed a comprehensive computational analysis pipeline for the systematic analysis and annotation of functionally relevant variants in the genome. This study follows a systematic and intuitive data analysis workflow to annotate genome variations and its potential functional effects. Moreover, we integrate predictive analysis of pharmacogenomic traits with emphasis on drugs for which pharmacogenomic testing has been recommended. This study thus provides the template for genome-scale analysis of personal genomes for personalized medicine.  相似文献   
998.

OBJECTIVE

To examine whether circulating total and high–molecular weight (HMW) adiponectin concentrations, measured before pregnancy, are associated with subsequent risk of gestational diabetes mellitus (GDM).

RESEARCH DESIGN AND METHODS

This was a nested case-control study among women who participated in the Kaiser Permanente Northern California Multiphasic Health Check-up exam (1984–1996) with a serum sample obtained and who had a subsequent pregnancy (1984–2009). Eligible women were free of recognized diabetes. Case subjects were the 256 women who developed GDM. Two control subjects were selected for each case and matched for year of blood draw, age at exam, age at pregnancy, and number of intervening pregnancies.

RESULTS

Compared with the highest quartile of adiponectin, the risk of GDM increased with decreasing quartile (odds ratio [OR] 1.5 [95% CI 0.7–2.9], 3.7 [1.9–7.2], and 5.2 [2.6–10.1]; Ptrend <0.001) after adjustment for family history of diabetes, BMI, parity, race/ethnicity, cigarette smoking, and glucose and insulin concentrations. Similar estimates were observed for HMW (Ptrend <0.001). The combined effects of having total adiponectin levels below the median (<10.29 mg/mL) and being overweight or obese (BMI ≥25.0 kg/m2) were associated with a sevenfold increased risk of GDM compared with normal-weight women with adiponectin levels above the median (OR 6.7 [95% CI 3.6–12.5]).

CONCLUSIONS

Prepregnancy low adiponectin concentrations, a marker of decreased insulin sensitivity and altered adipocyte endocrine function, is associated with reduced glucose tolerance during pregnancy and may identify women at high risk for GDM to target for early intervention.Gestational diabetes mellitus (GDM), defined as glucose intolerance with onset or first diagnosis during pregnancy, is a common complication of pregnancy. Women with a history of GDM have a sevenfold increased risk of developing type 2 diabetes after delivery (1), and the children of women with GDM are more likely to be obese and develop diabetes (2,3). The underlying etiology of GDM appears to be similar to the physiological abnormalities that characterize diabetes outside of pregnancy and is thought to be due to an inability of the pancreatic β-cells to compensate for the increased insulin resistance induced by pregnancy (4,5). The extent to which insulin resistance or reduced insulin sensitivity leading to GDM occurs even years before pregnancy has not been determined in population-based studies. There is increasing interest in identifying prepregnancy risk factors and biomarkers for GDM to inform future preconception prevention strategies, given the proven success of specific prevention strategies for type 2 diabetes in high-risk populations (6).Adiponectin is an abundant adipocyte-derived hormone demonstrated to have actions consistent with protection against insulin resistance, inflammation, and atherosclerosis (7). Total adiponectin circulates in the bloodstream as three discrete complexes: a lower–molecular weight trimer, a mid–molecular weight hexamer, and a high–molecular weight (HMW) complex (8). Some evidence suggests that HMW adiponectin is the isoform that mediates the insulin-sensitizing and antiatherogenic effects (9,10). Prospective studies examining adiponectin and incident type 2 diabetes reported that lower circulating total adiponectin concentrations were associated with a higher risk of type 2 diabetes in a dose-response relationship (11). Both total adiponectin (12) and HMW adiponectin (13) are known to decrease significantly in normal pregnancies in response to decreased insulin sensitivity; therefore, it is important to determine whether prepregnancy levels of adiponectin are related to subsequent risk of GDM in order to clarify the temporal sequence of the association. The aim of this study is to examine the association between prepregnancy total and HMW adiponectin concentrations and the risk of developing GDM and to determine whether these associations are independent of known metabolic risk factors for GDM.  相似文献   
999.
Myelodysplastic syndromes (MDS) are a group of disorders characterized by variable cytopenias and ineffective hematopoiesis. Hematopoietic stem cells (HSCs) and myeloid progenitors in MDS have not been extensively characterized. We transplanted purified human HSCs from MDS samples into immunodeficient mice and show that HSCs are the disease-initiating cells in MDS. We identify a recurrent loss of granulocyte-macrophage progenitors (GMPs) in the bone marrow of low risk MDS patients that can distinguish low risk MDS from clinical mimics, thus providing a simple diagnostic tool. The loss of GMPs is likely due to increased apoptosis and increased phagocytosis, the latter due to the up-regulation of cell surface calreticulin, a prophagocytic marker. Blocking calreticulin on low risk MDS myeloid progenitors rescues them from phagocytosis in vitro. However, in the high-risk refractory anemia with excess blasts (RAEB) stages of MDS, the GMP population is increased in frequency compared with normal, and myeloid progenitors evade phagocytosis due to up-regulation of CD47, an antiphagocytic marker. Blocking CD47 leads to the selective phagocytosis of this population. We propose that MDS HSCs compete with normal HSCs in the patients by increasing their frequency at the expense of normal hematopoiesis, that the loss of MDS myeloid progenitors by programmed cell death and programmed cell removal are, in part, responsible for the cytopenias, and that up-regulation of the “don’t eat me” signal CD47 on MDS myeloid progenitors is an important transition step leading from low risk MDS to high risk MDS and, possibly, to acute myeloid leukemia.  相似文献   
1000.
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