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81.
The growth rate of 31 asymptomatic hepatocellular carcinomas (diameter less than or equal to 5 cm) discovered in 28 patients by a prospective screening program was determined by real-time ultrasonography over 36-860 days. Except for one tumor that shrank on follow-up, the doubling time ranged from 29 to 398 days, with a median of 117 days, an arithmetic mean of 136 days, and a geometric mean of 110 days. In 17 tumors with more than two measurements, the growth rate remained exponential in nine, declined in growth in seven, and showed an initial lag period in one. Doubling time correlated with initial tumor diameter but was independent of the patient's age, sex, hepatitis B surface antigen status, tumor location, liver function tests, stage of liver cirrhosis, histologic type, or grade of malignancy. Although initial alpha-fetoprotein levels did not correlate well with growth rate, in 14 patients with an exponential increase of serum alpha-fetoprotein, the alpha-fetoprotein doubling time was closely related to the tumor doubling time. Based on the above data, the median detectable subclinical period of hepatocellular carcinoma was deduced to be 3.2 yr, and the suitable screening interval for its early detection in our area was 4-5 mo.  相似文献   
82.
OBJECTIVE: The use of ultrasonography is widespread for both the diagnosis and treatment of liver tumors. However, the measurement of liver volume by ultrasonography is not commonly done. We report an original method of liver volumetry using ultrasonography and an investigation into the usefulness of ultrasonography in this context. METHODS: The data for 50 patients undergoing various types of major hepatectomy were collected. We preoperatively measured liver volume using ultrasonography, dividing the liver into three main compartments according to precise anatomical landmarks, and then made comparisons with the volume of the actual specimen after hepatectomy, for all of the study participants. RESULTS: Total volume correlation between the two groups was good (r = 0.916, P < 0.001). However, the correlation was weaker in cases of right hepatectomy compared with other types of hepatectomy. CONCLUSION: This study demonstrates the possibility of doing liver volumetry using an ultrasound device. Further investigation to establish the reliability of this easily available and noninvasive approach is needed.  相似文献   
83.
INTRODUCTION: We report 2 cases of bilateral carotid thrombosis secondary to repeated attempts of strangulation. EXEGESIS: The first case was discovered in a 31-years-old woman who complained of psychiatric manifestations, memory loss and aphasia. Subsequently she developed hemiplegia which worsened under low dose aspirin. The second case occurred in a 41-years-old woman who presented with sudden hemiplegia and aphasia. Diagnosis of bilateral carotid thrombosis based on angiocomputerized tomography or angioRMI data which suggested dissection. Thrombosis location was similar: bilateral, symmetric, close to the carotid bifurcation. Both women had atherosclerosis risk factors: current smoking, use of estrogen containing pill, dyslipidemia and/or familial cardiovascular history. Search for thrombophilia was negative. Both women had been victims of intimate partner violence with repeated attempts of strangulation, but they were stopped 8 and 6 years before the diagnosis of carotid thrombosis. Several private interviews were necessary before knowing the exact cause. CONCLUSION: Symmetrical bilateral thrombosis of internal carotids near the bifurcation should lead to evoke repeated attempts of strangulation, even if there are arterial risk factors, and especially if the patient is a middle-aged female. The therapy is not codified but prolonged anticoagulation is generally prescribed.  相似文献   
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Knowledge about vitamin D has greatly improved during the last few years. Vitamin D cannot any more be considered as exclusively necessary to prevent ricket/osteomalacia. Its role in the prevention of some osteoporotic fractures in the elderly (in association with calcium nutrition) is now well demonstrated and many epidemiologic and laboratory data argue for a role in the prevention of several diseases or anomalies (cancer, auto-immune diseases, cardiovascular events, sarcopenia...). A few intervention studies confirming some of these effects also exist. Vitamin D status can easily be assessed by measuring serum 25 hydroxy vitamin D (25OHD) level. However, many experts have claimed that the population-based reference values for 25OHD are too low and that the cut-off value below which vitamin D insufficiency can be present is somewhere between 20 and 40 ng/mL with a clear tendency to target values above 30 ng/mL (75 nmol/L). The main consequences are that vitamin D insufficiency is highly frequent whereas the currently recommended supplementation doses are not sufficient.  相似文献   
86.
T H Wang  J T Lin  D S Chen  J C Sheu  J L Sung 《Pancreas》1986,1(3):219-223
One-hundred-forty patients with clinical impression of pancreatic cancer were examined prospectively with three noninvasive tests: real-time ultrasonography, determination of serum carcinoembryonic antigen (CEA), and carbohydrate antigen (CA 19-9). Among them, 24 (17.1%) patients were found to have pancreatic cancer. The sensitivity of ultrasonography, CEA, and CA 19-9 was 72.9%, 70.8%, and 83.3%, respectively; the specificity was 94.0%, 77.6%, and 90.5%, respectively, and the diagnostic accuracy was 91.4%, 76.4%, and 89.3%, respectively. The combination of ultrasonography and determination of serum CA 19-9 had better sensitivity (95.8%), comparable specificity (84.5%), and comparable diagnostic accuracy (86.4%) to any individual test alone or any other combination. It was suggested that combined use of real-time ultrasonography and determination of serum CA 19-9 provided excellent noninvasive screening for patients suspected of having pancreatic cancer.  相似文献   
87.
In response to aggravation by activated microglia, IL‐13 can significantly enhance ER stress induction, apoptosis, and death via reciprocal signaling through CCAAT/enhancer‐binding protein alpha (C/EBP‐α) and C/EBP‐beta (C/EBP‐β). This reciprocal signaling promotes neuronal survival. Since the induction of cyclooxygenase‐2 (COX‐2) and peroxisome proliferator‐activated receptor gamma/heme oxygenase 1 (PPAR‐γ/HO‐1) by IL‐13 plays a crucial role in the promotion of and protection from activated microglia, respectively; here, we investigated the role of IL‐13 in regulating C/EBPs in activated microglia and determined its correlation with neuronal function. The results revealed that IL‐13 significantly enhanced C/EBP‐α/COX‐2 expression and PGE2 production in LPS‐treated microglial cells. Paradoxically, IL‐13 abolished C/EBP‐β/PPAR‐γ/HO‐1 expression. IL‐13 also enhanced ER stress‐evoked calpain activation by promoting the association of C/EBP‐β and PPAR‐γ. SiRNA‐C/EBP‐α effectively reversed the combined LPS‐activated caspase‐12 activation and IL‐13‐induced apoptosis. In contrast, siRNA‐C/EBP‐β partially increased microglial cell apoptosis. By NeuN immunochemistry and CD11b staining, there was improvement in the loss of CA3 neuronal cells after intrahippocampal injection of IL‐13. This suggests that IL‐13‐enhanced PLA2 activity regulates COX‐2/PGE2 expression through C/EBP‐α activation. In parallel, ER stress‐related calpain downregulates the PPAR‐γ/HO‐1 pathway via C/EBP‐β and leads to aggravated death of activated microglia via IL‐13, thereby preventing cerebral inflammation and neuronal injury.  相似文献   
88.
Chromosome 11q13.5 containing RSF1 (HBXAP), a gene involved in chromatin remodelling, is amplified in several human cancers including ovarian carcinoma. Our previous studies demonstrated requirement of Rsf‐1 for cell survival in cancer cells, which contributed to tumour progression; however, its role in tumourigenesis has not yet been elucidated. In this study, we co‐immunoprecipitated proteins with Rsf‐1 followed by nanoelectrospray mass spectrometry and identified cyclin E1, besides SNF2H, as one of the major Rsf‐1 interacting proteins. Like RSF1, CCNE1 is frequently amplified in ovarian cancer, and both Rsf‐1 and cyclin E1 were found co‐up‐regulated in ovarian cancer tissues. Ectopic expression of Rsf‐1 and cyclin E1 in non‐tumourigenic TP53mut RK3E cells led to an increase in cellular proliferation and tumour formation by activating cyclin E1‐associated kinase (CDK2). Tumourigenesis was not detected if either cyclin E1 or Rsf‐1 was expressed, or they were expressed in a TP53wt background. Domain mapping showed that cyclin E1 interacted with the first 441 amino acids of Rsf‐1. Ectopic expression of this truncated domain significantly suppressed G1/S‐phase transition, cellular proliferation, and tumour formation of RK3E‐p53R175H/Rsf‐1/cyclin E1 cells. The above findings suggest that Rsf‐1 interacts and collaborates with cyclin E1 in neoplastic transformation and TP53 mutations are a prerequisite for tumour‐promoting functions of the RSF/cyclin E1 complex.  相似文献   
89.
Postherpetic neuralgia is the most common complication of herpes zoster which is caused by a reactivation of latent varicella zoster virus. The pathogenesis of postherpetic neuralgia may involve peripheral and central mechanisms. Reported risk factors for postherpetic neuralgia include female gender, old age, diminished cell-mediated immunity and nutritional deficiencies. Based on our clinical observation which revealed that peptic ulcer disease (PUD) is one of the common comorbidities in patients with postherpetic neuralgia, we hypothesize that herpes zoster patients with PUD may be at a greater risk for the development of postherpetic neuralgia due to their impaired cellular immunity and depressed nutritional status. Major causes of PUD include Helicobacter pylori infection and usage of ulcerogenic medications. Patients with H. pylori infection may develop T cell dysfunctions and nutritional deficiencies including vitamin C, iron, cobalamin, carotenes and alpha-tocopherol. Ulcerogenic medications such as nonsteroidal anti-inflammatory drugs and steroids have been found not only to be ulcerogenic but also immunosuppressive to T cells. In addition, usage of steroids and nonsteroidal anti-inflammatory drugs may cause deficiencies of alpha-tocopherol, carotenes, cobalamin, iron, zinc and vitamin C. Vitamin C, carotenes and alpha-tocopherol are anti-inflammatory and the major oxidant scavengers in the aqua phase and biomembranes. Deficiencies of these nutrients may induce dysregulated inflammation and oxidative damage leading to neuropathic pain in patients with herpes zoster. Furthermore, nutrient deficiencies including zinc, iron, cobalamin and vitamin C are associated with dysregulation of Ca(v)3.2 T-channels and N-methyl-d-aspartate receptors, upregulation of nitric oxide synthase, the increase of nitric oxide formation and dysfunction of central norepinephrine inhibitory pain pathway. Prospective cohort studies are suggested to test the hypothesis. We further propose that a follow-up study that contains two groups of herpes zoster patients, i.e., with or without gastroendoscopy-proven PUD, be conducted to determine their incidence of postherpetic neuralgia. In addition, despite of the high proportion of zoster patients having been treated with antiviral therapies, prevention and treatment of postherpetic neuralgia remain challenging in clinical practice. The potential risk of postherpetic neuralgia in zoster patients with PUD could mean that physicians need to pay more attention to the comorbidity - PUD in patients with herpes zoster and treat PUD earlier in order to prevent the development of postherpetic neuralgia.  相似文献   
90.
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