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1.
We studied seven examples of the solid variant of adenoid cystic carcinoma of the uterine cervix in postmenopausal women who presented with vaginal bleeding and a large ulcerated or polypoid cervical mass. The tumors lacked the characteristic cribriform pattern of conventional adenoid cystic carcinoma. The neoplastic cells were small, undifferentiated, or basaloid and grew in cords, nests, trabeculae, and nodules. Foci of squamous cell carcinoma were seen in three tumors and areas of necrosis in four. A characteristic feature was the production of abundant periodic acid-Schiff's procedure (PAS)-positive basement membrane material that was immunoreactive for collagen IV and that in some areas compressed tumor cells. Electron microscopy on three cases showed globules and cylinders of redundant basal lamina. The tumor cells were joined by desmosomes and contained bundles of tonofilaments. Material similar to basement membrane material appeared to be intracytoplasmic in two tumors. No neurosecretory granules or myoepithelial cells were found. Four deaths were tumor related. Two patients are currently alive, but with local recurrence or metastases; another is alive and well 19 months after surgery. We believe that the solid variant of adenoid cystic carcinoma of the cervix is a distinctive neoplasm that should be separated from small cell carcinomas with or without endocrine features, adenoid basal cell carcinoma, and squamous cell carcinoma.  相似文献   
2.
In response to traumatic brain injury (TBI), neurons initiate neuroplastic processes through the activation of intracellular signaling pathways. However, the molecular mechanisms underlying neuroplasticity after TBI are poorly understood. To study this, we utilized the fluid-percussion brain injury (FPI) model to investigate alterations in the mammalian target of rapamycin (mTOR) signaling pathways in response to TBI. Mammalian target of rapamycin stimulates mRNA translation through phosphorylation of eukaryotic initiation factor 4E binding protein-1 (4E-BP1), p70 ribosomal S6 kinase (p70S6K), and ribosomal protein S6 (rpS6). These pathways coordinate cell growth and neuroplasticity via dendritic protein synthesis. Rats received sham surgery or moderate parasagittal FPI on the right side of the parietal cortex, followed by 15 mins, 30 mins, 4 h, 24 h, or 72 h of recovery. Using Western blot analysis, we found that mTOR, p70S6K, rpS6, and 4E-BP1 phosphorylation levels were significantly increased in the ipsilateral parietal cortex and hippocampus from 30 mins to 24 h after TBI, whereas total protein levels were unchanged. Using confocal microscopy to localize these changes, we found that rpS6 phosphorylation was increased in the parietal cortex and all subregions of the hippocampus. In accordance with these results, eIF4E, a key, rate-limiting mRNA translation factor, was also phosphorylated by mitogen-activated protein kinase-interacting kinase 1 (Mnk1) 15 mins after TBI. Together, these results suggest that changes in mRNA translation may be one mechanism that neurons use to respond to trauma and may contribute to the neuroplastic changes observed after TBI.  相似文献   
3.
Summary: Purpose: A prospective series of 643 persons with epilepsy attending a reference neurologic center in Medellin, Colombia, was examined by computed tomography (CT scan) or serology or both with the enzyme-linked immunoelectrotransfer blot assay (EITB) to assess the prevalence of Taenia solium cysticercosis. Methods: All presenting patients were consecutively enrolled in the study. Five hundred forty-six persons underwent cerebral CT scans; 376 of them also had serum EITB performed. Results: Prevalence of neurocys@ercosis by CT scan was 13.92%. Overall prevalence of T. solium antibodies with EITB was 9.82%, but for those with late-onset epilepsy (onset after age 30 years), prevalence increased to 17.5% and 19% for those who originated from outside urban Medellin. Seroprevalence in individuals with mixed lesions (cysts and calcifications) was 88.2% and 64.10% in those with live cysts. Conversely, only 2.72% of persons with CT findings not related to neurocysticercosis had positive EITB tests. Conclusions: Our study shows that an important proportion of individuals with epilepsy have radiologic or serologic evidence of T. solium infection, suggesting that neurocysticercosis is an important etiology for epilepsy in Colombia.  相似文献   
4.
Bone marrow-derived mesenchymal stem cells in repair of the injured lung   总被引:26,自引:0,他引:26  
We sought to determine whether an intact bone marrow is essential to lung repair following bleomycin-induced lung injury in mice, and the mechanisms of any protective effects conferred by bone marrow-derived mesenchymal stem cell (BMDMSC) transfer. We found that myelosupression increased susceptibility to bleomycin injury and that BMDMSC transfer was protective. Protection was associated with the differentiation of engrafted BMDMSC into specific and distinct lung cell phenotypes, with an increase in circulating levels of G-CSF and GM-CSF (known for their ability to promote the mobilization of endogenous stem cells) and with a decrease in inflammatory cytokines. In vitro, cells from injured, but not from normal, mouse lung produced soluble factors that caused BMDMSC to proliferate and migrate toward the injured lung. We conclude that bone marrow stem cells are important in the repair of bleomycin-injured lung and that transfer of mesenchymal stem cells protects against the injury. BMDMSC localize to the injured lung and assume lung cell phenotypes, but protection from injury and fibrosis also involves suppression of inflammation and triggering production of reparative growth factors.  相似文献   
5.
6.
Rheopheresis for sudden hearing loss (SHL)   总被引:1,自引:0,他引:1  
Rheopheresis has met an increasing interest and application in different disease conditions affecting microcirculation. Its last applications are for the management of Macular and Cochlear disorders. The sudden hearing loss syndrome is a condition that affects 20 out of 100,000 persons per year, reduces the patient's social interaction and quality of life. It is associated with vascular and coagulation risk factors and it is considered as a result of local hypoperfusion secondary both to inflammatory and dysimmune conditions determining inadequate NO release and endothelial dysfunction. Rheopheresis treatment is a new approach which brings to satisfactory clinical results. Cascade filtration, heparin induced lipid precipitation and conventional plasma exchange are equally effective, and only 2 sessions are required for producing long lasting benefits. Our experience is with 60 patients, 90% of which getting from partial to complete recovery after treatment as measured by pure tone audiometry.  相似文献   
7.
Combining the predictions of a set of classifiers has shown to be an effective way to create composite classifiers that are more accurate than any of the component classifiers. There are many methods for combining the predictions given by component classifiers. We introduce a new method that combine a number of component classifiers using a Bayesian network as a classifier system given the component classifiers predictions. Component classifiers are standard machine learning classification algorithms, and the Bayesian network structure is learned using a genetic algorithm that searches for the structure that maximises the classification accuracy given the predictions of the component classifiers. Experimental results have been obtained on a datafile of cases containing information about ICU patients at Canary Islands University Hospital. The accuracy obtained using the presented new approach statistically improve those obtained using standard machine learning methods.  相似文献   
8.
Single-strand conformation polymorphism (SSCP) has been developed as a method for detecting the presence of mutations in a segment of DNA. We applied it to the subtyping of the DR11 group of alleles. The SSCP patterns of DRB1-DR52 group-specific products were defined in cell lines representing the DRB1*1101-06 alleles, using non-denaturing acrylamide gel electrophoresis and silver staining. Only one set of gel electrophoresis conditions was able to discriminate the DR11 alleles tested. The protocol was validated in an analysis of 105 DR11-positive individuals previously typed by oligonucleotides probing. The study demonstrates the suitability of the SSCP technique to define the DRB1*1101-06 alleles, the technique being particularly valuable in confirming and extending the oligotyping of DRB1-DR52 heterozygous samples.  相似文献   
9.
Maternal and Child Health Journal - To identify and describe the frequency and characteristics of disrespect and abuse practices towards women during facility-based delivery in four hospitals in...  相似文献   
10.
An asymmetry of basal ganglia dopaminergic function has been demonstrated in rats and related to both spontaneous and drug-induced rotation. An electronic device that measures the same kind of rotational movements in humans has been developed, and we have utilized this "rotometer" to study spontaneous rotational movement in prepubertal children. There was no significant difference between boys and girls in their average rate of rotation; however, left hemisphere-dominant boys were stronger rotators than left hemisphere-dominant girls. Both boys and girls made significantly more full turns to the left than to the right. These findings did not vary with age. Our observations are strikingly different from those obtained in previous studies of normal adults, in which women were stronger rotators than men, left hemisphere-dominant women turned to the left, and left hemisphere-dominant men rotated to the right. This study suggests that maturational changes in rotational behavior must occur, perhaps progressing to the adult pattern during puberty. The rotometer used in this study may provide useful information regarding the status of the basal ganglia in children with specific neurobehavioral conditions such as attention deficit disorder and Tourette's syndrome.  相似文献   
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