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21.
Background and aims In extended liver resections, the preservation of vascular and biliary structures of the entire remnant liver is of paramount importance. The impact of venous outflow impairment and its consequences for liver regeneration and function are still a matter of debate. Materials and methods Rats (n = 75) were subjected to a 90% partial hepatectomy (PH), to a 70% liver resection with narrowing of the hepatic outflow of an additional 20% parenchyma (70%+ PH) or to an anatomic 70% PH. Postoperatively hepatocyte proliferation (Ki-67), liver function and survival were assessed. Gene expression analysis for markers of regeneration was determined by in-house complementary (DNA) arrays and quantitative real-time polymerase chain reaction (RT-PCR). Results Ninety percent PH led to a greater regenerative response as shown Ki-67 compared to animals with a 70%+PH (p < 0.05). However, liver function was equally impaired in both groups. Rats with 70% PH showed a greater proliferation index with less hepatic injury and better liver function. While mortality was 0% in the group of 70% PH, rats with 90% PH and 70+PH had a reduced survival of 75% (p < 0.05) Conclusion Venous outflow obstruction leads to an impairment of liver regeneration and liver function. In cases with critically small liver remnants, restoration of an adequate venous outflow may be mandatory.  相似文献   
22.
In this paper an explicit finite-difference time-domain scheme for solving the Maxwell's equations in non-staggered grids is presented. The proposed scheme for solving the Faraday's and Ampère's equations in a theoretical manner is aimed to preserve discrete zero-divergence for the electric and magnetic fields. The inherent local conservation laws in Maxwell's equations are also preserved discretely all the time using the explicit second-order accurate symplectic partitioned Runge-Kutta scheme. The remaining spatial derivative terms in the semi-discretized Faraday's and Ampère's equations are then discretized to provide an accurate mathematical dispersion relation equation that governs the numerical angular frequency and the wavenumbers in two space dimensions. To achieve the goal of getting the best dispersive characteristics, we propose a fourth-order accurate space centered scheme which minimizes the difference between the exact and numerical dispersion relation equations. Through the computational exercises, the proposed dual-preserving solver is computationally demonstrated to be efficient for use to predict the long-term accurate Maxwell's solutions.  相似文献   
23.
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   
24.
PURPOSE: To examine the imaging features of non-small cell lung carcinomas (NSCLC) overlooked at digital chest radiography (dCXR), and compare general and thoracic radiologists' performance for lung carcinoma detection at dCXR. METHODS: Frontal and lateral dCXR from 30 consecutive patients with lung carcinoma overlooked during initial interpretation and 30 normal controls were independently retrospectively reviewed by two blinded thoracic radiologists and, in a separate review, three blinded general radiologists. The location, size, histopathology, borders, presence of superimposed structures, and lesion opacity were recorded. Interobserver agreement was calculated, and the detection performance between thoracic and general radiologists was compared. RESULTS: The average patient age was 67.9 years (range 47-82 years). The average size of carcinomas missed by the thoracic radiologists was 18.1mm (range 10-32 mm). Lesion margins were circumscribed in 29% (2/7), and 71% (5/7) of missed lesions were obscured by anatomical superimposition. Seventy-one percent (5/7) of missed lesions were solid nodules on computed tomography (CT) images. Forty-three percent of lesions were located in the upper lobes and 63% were adenocarcinomas. Compared with general radiologists, the seven NSCLC missed by the thoracic radiologists tended to be smaller (p=0.063), had significantly lower CT density measurements (-92.4+/-87.5 HU versus -70+/-87.2 HU, p=0.050), and more commonly had an ill-defined margin (p=0.026). The clinical stage of the overlooked lesions did not differ between the two groups (p=0.480). CONCLUSIONS: The lesion size, location, conspicuity, and histopathology impact the likelihood of lung carcinoma detection at dCXR in a fashion similar to that of conventional film-screen techniques.  相似文献   
25.
We aimed to determine how to approach the axilla after finding a positive sentinel node (SN) for a woman with breast cancer in Taiwan. We used blue dye staining to identify the SN in 824 procedures on 811 patients with breast cancer small than 3 cm by a single surgeon. All patients underwent SN biopsy, followed by at least level II axillary dissection. All SNs were evaluated histologically and immunohistochemically with anti-cytokeratin antibodies. Non-SNs were examined by routine histology. SNs were identified in 814/824 procedures (98.8%). SN metastases were found in 286/814 (35.1%). Subsequent axillary dissections revealed tumors in non-SNs in 188 (65.7%) of these patients. There was a relatively high incidence of non-SN metastases in our population. Tumor exhibiting high nuclear grading, ER-, PR-, Erb-2/neu overexpression, lymphovascular invasion, increasing tumor size, multiple positive SNs, and macrometastatic size in SNs (> 2 mm) were all significantly correlated with non-SN metastases. Multivariate analysis showed that tumor size, the number of positive SNs, and the metastatic size in SNs were independent factors predicting the presence of positive non-SNs. Small (< 2 cm) cancers, having only micrometastatic foci in the SN and having only one SN involved are closely correlated with the tumor-free non-SNs. Our data will assist such patients regarding the need for axillary dissection after finding a positive SN.  相似文献   
26.
BACKGROUND: Antioxidants such as N-acetylcysteine and probucol have been used to protect patients from contrast media-induced nephrotoxicity. The mechanisms underlying these protective effects are not well understood. We hypothesized that acetylcysteine and probucol alter the activity of endogenous antioxidant enzyme activity. METHODS: Four weeks after induction of diabetes with streptozotocin, diabetic and nondiabetic rats were divided into three groups. Group 1 rats did not receive any antioxidant agents. Group 2 rats were treated with acetylcysteine and group 3 rats with probucol for 1 week before injection of the contrast medium diatrizoate (DTZ). RESULTS: We found that diabetic rats had higher renal glutathione peroxidase (GPx) activity than normal rats. DTZ suppressed renal GPx activity significantly in both group 1 diabetic and normal rats. Interestingly, renal GPx activity in both diabetic and normal rats pretreated with acetylcysteine or probucol was not inhibited by DTZ. Renal superoxide dismutase (SOD) increased significantly in normal rats after DTZ injection, but not in diabetic rats. Finally, acetylcysteine or probucol did not significantly influence renal SOD. CONCLUSIONS: These findings suggest that the renal protective effects of acetylcysteine and probucol against contrast-induced oxidative stress and nephrotoxicity may be mediated by altering endogenous GPx activity.  相似文献   
27.

Background

Spontaneous recovery of severe alopecia areata is rare and the condition is difficult to treat.

Objective

The aim of this study is to investigate and compare the effects and safety of steroid pulse therapy between oral and intravenous administrations between 1999 and 2010 at the Department of Dermatology, National Cheng Kung University Hospital.

Methods

Data were retrospectively retrieved. A satisfactory response was defined as more than 75% hair regrowth in the balding area.

Results

A total of 85 patients with more than 50% hair loss were identified and treated, with an overall satisfactory response rate of 51.8%. The mean follow-up time was 37.6 months, with a relapse rate of 22.7%. Patients with alopecia areata (hereafter, AA) of recent onset within one year showed higher response rates (p<0.001) and lower relapse rates compared to patients with AA persisting for more than 1 year. Further, even in patients with alopecia totalis, alopecia universalis or ophiasis type, early treatment resulted in a satisfactory response rate of 47% among the treated patients. In general, oral therapy was as effective and well-tolerated as intravenous therapy.

Conclusion

The response rate is determined by disease severity and time of intervention, not by the administration form of steroid pulse therapy. Oral steroid pulse therapy can be considered as the first-line treatment for patients with severe AA of recent onset within one year.  相似文献   
28.
The expression of the various markers for terminal epidermal differentiation in atrophic skin of patients after long-term topical corticosteroids (TCS) was studied by electron microscopy, immunofluorescence using antibody to profilaggrin/filaggrin (PF/FG), immunoperoxidase staining using antibody to involucrin, and oil red O stain for neural lipids of the stratum corneum. Thirty-nine patients were subdivided into two groups: (A) 19 patients suffering from rebound phenomenon after stopping TCS and (B) 20 patients without rebound phenomenon. Biopsy specimens were taken before ending the use of TCS in both groups. In group A, both the morphological markers (including the different epidermal strata, keratohyalin granules, lamellar granules, and cornified cell envelopes) and the molecular markers (including involucrin, PF/FG, and neutral lipids) of terminal epidermal differentiation were significantly suppressed. On the other hand, the differentiational markers in the atrophic skin of patients without rebound phenomena were only slightly altered. These results suggest that potent TCS not only has antiproliferative actions but also inhibits the differentiation of epidermis, resulting in structural defects in the epidermis, especially the stratum corneum.  相似文献   
29.

Purpose:

The purpose of this study is to identify the possible factors for preserving the eyes after late or suboptimally treated endogenous endophthalmitis secondary to Klebsiella pneumoniae (KP) liver abscess.

Methods:

A retrospective chart review was conducted for patients admitted with KP liver abscess from January 1991 to June 2012.

Results:

Six hundred and ninety-three patients with KP liver abscess were recorded, in which endophthalmitis was identified in 53 cases (65 eyes, 8.29%). Diabetes was significantly associated with the development of endophthalmitis (p = 0.014). Eleven eyes received their last ocular treatment ≥10 days and final vision ≥ counting fingers, and were defined as benign type KP endophthalmitis. The absence of diabetes was the only consistent candidate factor for benign type KP endophthalmitis.

Conclusion:

A lack of ongoing diabetes is an important factor in preserving eyes with late or suboptimally treated endogenous endophthalmitis second to KP liver abscess.  相似文献   
30.
Several studies have shown cardiovascular benefit in treating hypercholesterolemia with HMG-CoA reductase inhibitor. However, in addition to the lowering of cholesterol, the beneficial effects of this inhibitor reflect other pharmacological activities. Whether these beneficial effects are partly mediated by changes in fibrinolytic factors remains to be proven, since clinical studies on the effects of HMG-CoA reductase inhibitors on fibrinolytic factors have not yielded consistent results. The purpose of this study was to evaluate the effects of fluvastatin on fibrinolytic factors in hypercholesterolemic patients. After 6 weeks on a low-fat, low-cholesterol diet, 23 outpatients known to have primary hypercholesterolemia with low density lipoprotein cholesterol (LDL-C) > or = 130 mg/dl with at least 2 risk factors or fasting LDL-C > or = 160 mg/dl were selected for the study. Venous blood samples were collected at baseline and at 8 weeks after fluvastatin therapy (40 mg/day) to measure of tissue plasminogen activator (t-PA), plasminogen activators inhibitor-1 (PAI-1), fibrinogen, D-dimer and lipid profile. After 8 weeks of therapy, fluvastatin reduced serum cholesterol by 11% (261.9 mg/dl vs 233.2 mg/dl, P < 0.01) and LDL-C by 22% (191.9 mg/dl vs 149.3 mg/dl, P < 0.01). D-dimer was significantly decreased (0.38 ng/L vs 0.28 ng/L, P = 0.02) and tPA, PAI-1 and fibrinogen tended to decrease after therapy. Fluvastatin therapy improved fibrinolytic profile; the result of this study may in part explain the benefit of HMG-CoA reductase inhibitor on cardiovascular system other than lipid lowering.  相似文献   
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