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351.

Purpose  

Many osteoporotic vertebral fractures are not clinically recognized but increase fracture risk. We hypothesized that a newer generation densitometer increases the number of evaluable vertebrae and vertebral fractures detected. We also explored the impact of reader experience on vertebral fracture assessment (VFA) interpretation.  相似文献   
352.
We report a case of diverticulitis affecting a colonic segment used as an interposition graft following laryngopharyngectomy. The patient presented as an emergency to our department with a history of a red, swollen and painful neck. She had undergone laryngopharyngectomy for laryngeal cancer in 1967. Computed tomography imaging revealed several diverticula in the colonic graft and associated abscess formation. The patient’s clinical condition behaved similarly to that of conventional colonic diverticulitis. The difficulties in reaching a definite diagnosis and management of this unusual complication following laryngopharyngectomy are discussed.  相似文献   
353.
354.
Kitano  K; Baldwin  GC; Raines  MA; Golde  DW 《Blood》1990,76(10):1980-1988
Monocytotropic human immunodeficiency virus type 1 (HIV-1) isolates from patients with acquired immunodeficiency syndrome (AIDS) infect mononuclear phagocytes as well as activated T cells, but do not usually infect immature human myeloid cell lines in vitro. The HL-60 promyelocytic/myeloblastic cell line and the promonocytic line, U937, were susceptible to productive infection by monocytotropic HIV-1 isolates (HIV-1JR-FL and HTLV-IIIBa-L) after treatment with retinoic acid, dimethyl sulfoxide, dibutyryl cAMP, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), or 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Virus production was only detected when these compounds were added before virus infection. Virus replication did not correlate with CD4 receptor expression because undifferentiated HL-60 cells express CD4 and the level of CD4 expression did not increase after differentiation in the presence of retinoic acid, 1,25(OH)2D3, or TPA. A mature monocytic cell line (THP-1) was capable of infection without pretreatment, and treatment with differentiating agents enhanced virus production. A chronically infected cell line (J-HL-60) was isolated after HIV-1JR-FL infection of HL-60 cells treated with retinoic acid. Virus production in this cell line was enhanced more than 10-fold after differentiation in the presence of 1,25(OH)2D3 or TPA. The majority of virus production by 1,25(OH)2D3-treated J-HL-60 cells was associated with the mature, adherent population. Molecular analysis of a cloned line of J-HL-60 showed integration of a single DNA provirus. These results suggest that cellular factors associated with precursor cell differentiation along the myelomonocytic pathway are required for optimal replication of monocytotropic HIV-1 strains in vitro.  相似文献   
355.
We studied the effects of cis-retinoic acid (cisRA) on the clonogenic growth of samples of leukemic cells from 35 patients with acute nonlymphocytic leukemia (ANLL). We observed significant inhibition of leukemic colony growth in 17 samples by 10(-7) to 10(-6)M cisRA. However, we found that retinoid exposure resulted in striking stimulation of clonal growth in ten samples at the same drug concentrations. With the exception of cases with promyelocytic features, there was no morphologic or functional evidence that cisRA induced the leukemic blasts to differentiate. Both inhibition and stimulation were dose-dependent and observable at pharmacologically achievable levels of cisRA. Leukemic cells with monocytic features more frequently demonstrated a stimulatory response than did those without monocytic features. Depletion of T lymphocytes and monocytes did not alter the type of growth response. Assays for cellular retinoic acid- binding protein (CRABP) were performed on five samples (two with inhibitory growth responses, two with stimulatory responses, and one with no growth) and failed to reveal detectable levels of CRABP in any case. The addition of cisRA to liquid suspensions of leukemic cells produced no significant change in the number of viable cells. We conclude that the effects of cisRA on leukemic colony growth are not cytotoxic and not mediated by T lymphocytes, monocytes, or CRABP. More importantly, cisRA appears to enhance the growth of certain human leukemia cells in vitro. Taking into account the increasing use of retinoids in clinical trials for patients with leukemia, the latter findings may represent a significant cautionary note.  相似文献   
356.
Congestive heart failure as a cause of acute liver failure is rarely documented with only a few cases.Although the pathophysiology is poorly understood, there is rising evidence, that low cardiac output with consecutive reduction in hepatic blood flow is a main causing factor, rather than hypotension. In the setting of acute liver failure due to congestive heart failure, clinical signs of the latter can be absent, which requires an appropriate diagnostic approach.As a reference center for acute liver failure and liver transplantation we recorded from May 2003 to December 2007 202 admissions with the primary diagnoses acute liver failure. 13/202 was due to congestive heart failure, which was associated with a mortality rate of 54%. Leading cause of death was the underlying heart failure. Asparagine transaminase (AST), bilirubin, and international normalized ratio (INR) did not differ significantly in surviving and deceased patients at admission. Despite both groups had signs of cardiogenic shock, the cardiac index (CI) was significantly higher in the survival group on admission as compared with non-survivors (2.1 L/min/m2 vs. 1.6 L/min/m2, p = 0.04). Central venous - and pulmonary wedge pressure did not differ significantly. Remarkable improvement of liver function was recorded in the group, who recovered from cardiogenic shock.In conclusion, patients with acute liver failure require an appropriate diagnostic approach. Congestive heart failure should always be considered as a possible cause of acute liver failure.  相似文献   
357.
Astroblastoma is a rare central nervous system tumor. We reported a case of a 24‐year‐old Nepalese woman with radiological features mimicking pilocytic astrocytoma which came out to be low‐grade astroblastoma in histopathological and immunohistochemistry examination after total excision of the tumor.  相似文献   
358.
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