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101.
The histologic features of thymuses from three patients who underwent thymectomy for acute lymphoblastic leukemia or lymphoblastic lymphoma in complete clinical remission are described. The thymuses from all three patients were fibrotic with a variability in the appearance of the lobules. Some of the lobules consisted predominantly of epithelial cells with small numbers of mature appearing lymphocytes, while other lobules were expanded and composed predominantly of cells having morphological features of immature lymphoid cells consistent with residual or recurrent disease.  相似文献   
102.
GOALS: The purpose of this review is to look at the evidence presented in the literature on the immunoexpression of p27 in cancers of the gastrointestinal tract and liver. BACKGROUND: Cell cycle proteins have been shown to play an important role in the oncogenesis of many tumors. Several of these proteins have been examined in concert and in isolation, and some have been put forward as putative tumor markers. p27, which is an important inhibitory protein in the cell cycle and belonging to a group of cyclin-dependent kinase inhibitors, has also been studied in several malignancies, most notably breast, lung, bladder, and prostate cancers. Considerable work has also been done on the expression of this protein in cancers occurring within the gastrointestinal tract. RESULTS: Cancers occurring in the major sites of the gastrointestinal tract (esophagus, stomach, and colorectum) and liver show a similar pattern with regard to p27 protein levels. p27 emerges as a statistically significant predictor of survival and tumor behavior. It has been suggested that p27 loss occurs early in the carcinogenesis process, with dysplastic epithelium having decreased expression. The more aggressive, metastasizing cancers tend to lack p27 expression as well. Some studies have also invoked the subcellular localization of p27 (cytoplasmic versus nuclear) as also being of prognostic value. CONCLUSION: Therefore, in gastrointestinal and hepatic cancers, low p27 expression is regarded as an important adverse prognostic factor.  相似文献   
103.
Background:   The cholinergic nerve fibers of coronary arteries, capillaries and veins were studied in younger and older humans by staining of acetylcholinesterase and cholineacetyltransferase activities on autopsy samples of coronary vessels with the aim of investigating age-related changes.
Methods:   Samples of human coronary vessels were harvested and exposed to the enzymatic staining for acetylcholinesterase, immunohistochemical staining for cholineacetyltransferase and quantitative analysis of images. Morphometric values were subjected to statistical analysis of data.
Results:   Our results demonstrated that both acetylcholinesterase and cholineacetyltransferase are localized in the coronary vessels of younger and older humans. Staining of these two enzymes showed specific age-related changes. Structures resembling cholinergic nerve fibers were located in coronary vessels, in the extra-parenchymal (large caliber) and intraparenchymal (small caliber) branches (arteries and veins), organized in a plexus. Coronary arterioles of large caliber (diameter > 150 µm) were found to have many cholinergic nerve fibers. The quantitative analysis of images and the statistical analysis of the data demonstrated that the cholinergic neurotransmitters of coronary vessels (especially the extra-parenchymal branches of coronary arteries) strongly decrease with age.
Conclusions:   The age-related changes of cholinergic nerve supply of the human coronary vessels may play a role in the control of coronary circulation. Further studies are needed in order to draw definite conclusions concerning the nervous control of coronary circulation under normal and/or pathological conditions.  相似文献   
104.
The comparison of hemodilution at the end of surgery is of limited use as it represents only a snapshot of a dynamic phenomenon. This study was undertaken to compare the perioperative hemoglobin curves of isolated coronary artery bypass grafting performed with minimized extracorporeal circulation, traditional cardiopulmonary bypass, and off‐pump technique. The propensity score method was used to select three groups of patients, homogenous regarding preoperative and operative data, who underwent isolated coronary artery bypass grafting. A generalized linear mixed model was used for estimating differences in perioperative hemoglobin trends among groups. The three groups were each composed of 50 patients with no differences in demographic data, preoperative risk profile, preoperative hemoglobin, or type of surgery. There was no significant difference in major postoperative complications. The pattern of the hemodilution curves was similar in patients operated with mini‐circuit and off‐pump technique (P > 005). Mini‐circuit led to a 3.1 ± 11.9% hemoglobin reduction, which was similar to the off‐pump group (1.6 ± 8.9%, P = 0.99 at ANOVA) and significantly different from the standard extracorporeal circuit group (16.0 ± 10.3%, P < 0.001 at ANOVA). The generalized linear mixed model determined that the standard circuit was the only independent predictor for increased hemodilution. Its effect on hemodilution was time‐dependent and the slope of the hemoglobin curve was more pronounced between systemic heparinization and the end of surgery. Perioperative hemoglobin trends of patients who underwent myocardial revascularization with mini‐circuit were similar to those of off‐pump surgery and significantly less pronounced than those of standard extracorporeal circulation.  相似文献   
105.
Hypothermia is a promising therapeutic strategy for severe vasospasm and other types of non-thrombotic cerebral ischemia, but its clinical application is limited by significant systemic side effects. We aimed to develop an intraventricular device for the controlled cooling of the cerebrospinal fluid, to produce a targeted hypothermia in the affected cerebral hemisphere with a minimal effect on systemic temperature. An intraventricular cooling device (acronym: V-COOL) was developed by in silico modelling, in vitro testing, and in vivo proof-of-concept application in healthy Wistar rats (n = 42). Cerebral cortical temperature, rectal temperature, and intracranial pressure were monitored at increasing flow rate (0.2 to 0.8 mL/min) and duration of application (10 to 60 min). Survival, neurological outcome, and MRI volumetric analysis of the ventricular system were assessed during the first 24 h. The V-COOL prototyping was designed to minimize extra-cranial heat transfer and intra-cranial pressure load. In vivo application of the V-COOL device produced a flow rate-dependent decrease in cerebral cortical temperature, without affecting systemic temperature. The target degree of cerebral cooling (− 3.0 °C) was obtained in 4.48 min at the flow rate of 0.4 mL/min, without significant changes in intracranial pressure. Survival and neurological outcome at 24 h showed no significant difference compared to sham-treated rats. MRI study showed a transient dilation of the ventricular system (+ 38%) in a subset of animals. The V-COOL technology provides an effective, rapid, selective, and safe cerebral cooling to a clinically relevant degree of − 3.0 °C.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13311-022-01302-y.  相似文献   
106.
Stage I-II melanoma: the value of metastatic work-up   总被引:3,自引:0,他引:3  
A total of 116 asymptomatic patients with malignant skin melanoma entered a multiple staging work-up including chest X-ray, multiple nuclear scans and abdominal ultrasonography. All 116 chest X-rays and 68 brain scans performed gave negative findings. Liver scans resulted in 1/66 false-positive findings. Out of 73 bone scans, 5 gave false-positive results. Only 2 out of 66 abdominal ultrasonographies showed abnormal findings and were found to be true-positive on surgical exploration. Due to the low yield in detecting silent metastases, such a multiple staging work-up would not be regarded as a routine staging program.  相似文献   
107.
Recurrent pulmonary embolism after Greenfield filter placement   总被引:1,自引:0,他引:1  
Geisinger  MA; Zelch  MG; Risius  B 《Radiology》1987,165(2):383-384
Three patients with documented recurrent pulmonary embolism with an inferior vena cava (IVC) Greenfield filter in place were examined with contrast-material-enhanced cavography. Mechanisms for recurrent pulmonary embolism were found to be propagation of thrombus through the filter struts, occlusion of the IVC at the level of the filter, and loss of contact of the filter hooks with a portion of the caval wall.  相似文献   
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