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BACKGROUND & AIMS: Intraductal papillary-mucinous tumor (IPMT) of the pancreatic ducts is increasingly recognized. This study investigated if clinical, imaging, or, histological features predicated outcome, formulated a treatment algorithm, and clarified relationships among IPMT, mucinous cystic neoplasms of the pancreas (MCN), and chronic pancreatitis. METHODS: The medical records, radiographs, and pathological specimens of 15 patients with IPMT (dilated main pancreatic duct or branch ducts with mucin overproduction) who were evaluated between October 1983 and January 1994 were reviewed. RESULTS: One patient had hepatic metastases. Fourteen underwent an operation (6 distal pancreatectomy, 4 total pancreatectomy, and 4 pancreaticoduodenectomy); all had dysplastic intraductal epithelium and chronic pancreatitis, whereas 3 had invasive adenocarcinoma. After a median of 25 months, 10 patients were alive; 3 of 4 with malignant and 2 of 11 with benign IPMT died (P < 0.05). Patients with or without carcinoma had similar clinical and radiographic features. A clinical diagnosis of chronic pancreatitis had been made in 9 patients with benign IMPT and in none with malignant IPMT (P < 0.05). CONCLUSIONS: IPMT is a dysplastic and likely precancerous lesion that is frequently diagnosed as chronic pancreatitis and is separate from MCN. Because it is not possible to distinguish noninvasive from invasive IPMT preoperatively, complete surgical excision of the dysplastic process is our treatment of choice whenever appropriate. (Gastroenterology 1996 Jun;110(6):1909-18)  相似文献   
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Neurocysticercosis is the most frequent parasitic infection of the CNS and the main cause of acquired epilepsy worldwide. Seizures are the most common symptoms of the disease, together with headache, involuntary movements, psychosis and a global mental deterioration. Absolute diagnostic criteria include the identification of cysticerci, with scolex, in the brain by MRI imaging. We demonstrate here, for the first time, that T. solium DNA is present in the cerebrospinal fluid of patients. The PCR amplification of the parasite DNA in the CSF enabled the correct identification of 29/30 cases (96.7 %). The PCR diagnosis of parasite DNA in the CSF may be a strong support for the diagnosis of neurocysticercosis.  相似文献   
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Multi-unit ribozyme-mediated cleavage of bcr-abl mRNA in myeloid leukemias   总被引:1,自引:0,他引:1  
Leopold  LH; Shore  SK; Newkirk  TA; Reddy  RM; Reddy  EP 《Blood》1995,85(8):2162-2170
Chronic myelogenous leukemia is characterized by the Philadelphia chromosome, which at the molecular level results from the fusion of the bcr gene on chromosome 22 and the abl gene on chromosome 9. The bcr-abl fusion gene encodes a novel tyrosine kinase with transforming activity. In this study, we have synthesized a multi-unti ribozyme that targets bcr-abl mRNA. In vitro ribozyme cleavage reactions show increased cleavage efficiency of this multi-unit ribozyme compared with single or double ribozymes. The multiunit ribozyme was then transfected into murine myeloblasts transformed with the bcr-abl gene (32D cells). Ribozyme transfection was accomplished either by liposomes or using follic acid-polylysine as a carrier. Multi-unit ribozyme transfection reduced the level of bcr-abl mRNA 3 logs when transfected via folate receptor-mediated uptake into transformed 32D cells. These results suggest that a multi-unit ribozyme could be an effective therapeutic agent for the treatment of Philadelphia chromosome-positive chronic myelogenous leukemia.  相似文献   
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Some rare HIV-1-infected individuals, referred to as HIV controllers (HIC), have persistently undetectable plasma viral load in the absence of therapy. This control of HIV-1 replication has been associated with a strong, multifunctional specific CD8(+) T cell response. However, no direct link between this immune response and the control of viremia has so far been provided. We investigated parameters of specific CD8(+) T cell response and in vitro susceptibility to HIV-1 infection in 11 HIC. We found high frequencies of HIV-specific CD8(+) T cells. Interestingly, these cells expressed the activation marker HLA-DR but not CD38. This unique phenotype differentiates HIV-specific CD8(+) T cells from HIC and noncontroller subjects and likely reflects a high potential to expand upon exposure to antigen and a capacity to exert effector functions. Accordingly, although CD4(+) T cells from HIC were fully susceptible to HIV-1 superinfection, their CD8(+) T cells effectively suppressed HIV-1 infection. Remarkably, this potent anti-HIV activity was observed without prior stimulation of CD8(+) T cells. This activity was not mediated by secreted inhibitory factors but was due to the elimination of infected CD4(+) T cells and was observed only with autologous CD4(+) T cells, indicating an HLA-restricted cytotoxic mechanism. This constitutive antiviral capacity of CD8(+) T cells could account for the control of viral replication in HIC.  相似文献   
96.
Joneckis  CC; Ackley  RL; Orringer  EP; Wayner  EA; Parise  LV 《Blood》1993,82(12):3548-3555
The abnormal adherence of red blood cells, especially circulating reticulocytes (erythrocyte precursors), to the endothelium is believed to contribute to vascular occlusion observed in patients with sickle cell disease. Although several plasma proteins including von Willebrand factor and fibronectin have been proposed to mediate this adhesion, the mechanism of sickle cell adhesion to the endothelium remains unknown. Using flow cytometry, we screened sickle red blood cells with monoclonal antibodies (MoAbs) against known adhesion receptors and detected integrin subunits alpha 4 and beta 1 and the nonintegrin glycoprotein IV on reticulocytes but not on erythrocytes. No reactivity was detected against integrin subunits alpha 2, alpha 3, alpha 5, alpha 6, alpha v, beta 2, beta 3, integrin alpha IIb beta 3, or the nonintegrin glycoprotein Ib. Immunoprecipitation of reticulocytes with either alpha 4- or beta 1-specific antibodies identified the alpha 4 beta 1 complex (alpha 4(70) and alpha 4(80) forms), a receptor for fibronectin and vascular cell adhesion molecule-1. An antibody against glycoprotein IV, a receptor reported to bind thrombospondin and collagen, immunoprecipitated an 88-kD protein consistent with its reported M(r). MoAbs against alpha 4 and glycoprotein IV bound to an average of 4,600 and 17,500 sites per reticulocyte, respectively. Identification of alpha 4 beta 1 and glycoprotein IV on reticulocytes suggests both plasma-dependent and independent mechanisms of reticulocyte adhesion to endothelium and exposed extracellular matrix.  相似文献   
97.

BACKGROUND

Many state agencies have developed model wellness policies (MWPs) to serve as examples for schools when writing their own school wellness policy (SWP). The purpose of this study was to evaluate if a MWP aids schools in writing stronger, more comprehensive SWPs.

METHODS

For this cross‐sectional study, 91 school districts submitted their current SWP and completed a survey that classified districts into either districts that utilized the state MWP (N = 56; 61.5%) or those that did not (NMWP, N =35; 38.5%). The Wellness School Assessment Tool (WellSAT) was used to assess the strength, comprehensiveness, total overall score, and subsection scores of each policy. Dependent variables were compared between groups using t tests. Statistical significance was set at p ≤ .05. Data are presented as mean ±SD.

RESULTS

No significant differences were found between groups in total overall (MWP 76.8 ± 37.9; NMWP 62.1 ± 34.3), strength (MWP 25.3 ± 17.6; NMWP 19.1 ± 12.8), or comprehensiveness scores (MWP 51.5 ± 21.2; NMWP 43.0 ± 22.1). The only subsection score difference identified between groups was the Nutrition Standards comprehension score (p = .02).

CONCLUSIONS

These data suggest MWPs may not improve the quality of written SWPs. Further research is needed to better understand the needs of school districts in SWP development.
  相似文献   
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