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41.
Serial plain radiographic, ultrasound and CT findings of an unusual case of pulmonary blastoma are described with a review of the literature.  相似文献   
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Human Herpesvirus-6 is the etiological agent of Roseola infantum and approximately 12% of heterophile antibody negative infectious mononucleosis. HHV-6 is T-lymphotropic, and readily infects and lyses CD4+ cells. The prevalence rate of HHV-6 in the general population is about 80% (as measured by IFA) with an IgG antibody titer of 1:80. A lower prevalence, however, is observed in some countries. HHV-6 is reactivated in various malignant and non-malignant diseases as well as in Chronic Fatigue Syndrome and transplant patients. Furthermore, elevated antibody titers were also observed in lymphoproliferative disorders, auto-immune diseases and HIV-1 positive AIDS patients. There appears to be some strain variability in HHV-6 isolates. The GS isolates of HHV-6 (prototype) was resistant to Acyclovir, Gancyclovir, but its replication was inhibited by Phosphonoacetic acid and Phosphoformic acid. HHV-7 isolated from healthy individuals showed, by restriction analysis, that 6 out of 11 probes derived from two strains of HHV-6, cross-hybridized with DNA fragments, derived from HHV-7.  相似文献   
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Uptake of indium-labeled leukocytes was seen in two cases of histologically proven brain metastasis. In one, this led to misdiagnosis of the lesion as an abscess. On histological evaluation, a large number of white blood cells or macrophages was seen at the neoplastic sites. Reasons for leukocyte accumulation around metastatic brain neoplasms are discussed. In contrast to the current reports that indium-labeled leukocyte scans can differentiate intracranial infection from tumor, these cases demonstrate their lack of specificity in the detection of brain abscess.  相似文献   
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(+)-Discodermolide, a C24:4, trihydroxylated, octamethyl, carbamate-bearing fatty acid lactone originally isolated from a Caribbean sponge, has proven to be the most potent of the microtubule-stabilizing agents. Recent studies suggest that it or its analogues may have advantages over other classes of microtubule-stabilizing agents. (+)-Discodermolide's complex molecular architecture has made structure-activity relationship analysis in this class of compounds a formidable task. The goal of this study was to prepare simplified analogues of (+)-discodermolide and to analyze their biological activities to expand structure-activity relationships. A small library of analogues was prepared wherein the (+)-discodermolide methyl groups at C-14 and C-16 and the C-7 hydroxyl were removed, and the lactone was replaced by simple esters. The library components were analyzed for microtubule-stabilizing actions in vitro, antiproliferative activity against a small panel of human carcinoma cells, and cell signaling, microtubule architecture and mitotic spindle alterations by a multiparameter fluorescence cell-based screening technique. The results show that even drastic structural simplification can lead to analogues with actions related to microtubule targeting and signal transduction, but that these subtle effects were illuminated only through the high information content cell-based screen.  相似文献   
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Detection of hemoperitoneum in splenic trauma is as important as detection of the visceral injury itself. Observation of a consistent spectrum of fluid accumulation in patients with splenic trauma prompted us to investigate the patterns in more detail. Twenty-three computed tomographic (CT) scans in 20 patients were evaluated with respect to presence of fluid collections in various peritoneal and retroperitoneal compartments. These were correlated with severity of injury and operative and pathologic findings. Hemoperitoneum was detected in the pelvis (65%), paracolic gutters (52%), left subphrenic space (48%), perihepatic space (48%), Morison's pouch (17%) and in the lesser sac (9%). In addition to free fluid, pleural fluid (39%) and retroperitoneal hematoma in the left anterior pararenal space (13%) were also encountered. These ancillary findings may help to substantiate the diagnosis of splenic trauma in equivocal cases, particularly when the spleen itself is obscured by artifacts. Early detection may reduce mortality and morbidity associated with splenic trauma.  相似文献   
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Background

Hepatic resection of colorectal liver metastases is associated with long-term survival. This study analyzes actual 10-year survivors after resection of colorectal liver metastases, reports the observed rate of cure, and identifies factors that preclude cure.

Methods

A single-institution, prospectively maintained database was queried for all initial resections for colorectal liver metastases for the years 1992–2004. Observed cure was defined as actual 10-year survival with either no recurrence or resected recurrence with at least 3 years of disease-free follow-up. Clinical risk score was dichotomized into low (0–2) and high (3–5). Semiparametric proportional hazards mixture cure model was utilized to estimate probability of cure.

Results

We included 1,211 patients with a median follow-up for survivors of 11 years. Median disease-specific survival was 4.9 years (95% CI: 4.4–5.3). 295 patients (24.4%) were actual 10-year survivors. The observed cure rate was 20.6% (n?=?250). Among 250 cured patients, 192 (76.8%) had no recurrence and 58 (23.2%) had a resected recurrence with at least 3 years of disease-free follow-up. Extrahepatic disease (n?=?88), carcinoembryonic antigen >200?ng/mL (n?=?119), positive margin (n?=?109), and >10 tumors (n?=?31) had observed cure rates less than 10%. In cure model analysis, patients with both extrahepatic disease and high clinical risk score (n?=?31) had an estimated probability of cure of 3.5%.

Conclusion

Actual 10-year survival after resection of colorectal liver metastases is 24% with an observed 20% cure rate. Patients with both high clinical risk score and extrahepatic disease have an estimated probability of cure less than 5%. When such factors are identified, strong consideration may be given to preoperative strategies, such as neoadjuvant chemotherapy, to help select patients for surgical therapy.  相似文献   
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