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BACKGROUND: Since the advent of cisplatin-based chemotherapy, the majority of metastatic testicular cancers can be cured by chemotherapy followed by retroperitoneal lymph node dissection (RPLND). However, postchemotherapy RPLND confers no therapeutic benefit if the residual mass contains no viable cells. Therefore, to determine which parameters predict a patient's likelihood of having only necrosis in the residual mass, we retrospectively analyzed clinical parameters of patients who underwent postchemotherapy RPLND. METHODS: Data from 27 patients with metastatic testicular cancer were analyzed. The histology of the primary tumor was seminoma in 11 cases and non-seminoma in 16 cases. All of the patients with non-seminoma showed a normalization of tumor markers after chemotherapy. Analysis of clinical parameters included data for the initial histology, pretreatment tumor marker levels, postchemotherapy retroperitoneal mass size, and the histology of the dissected RPLNs. RESULTS: Histological examination of dissected RPLNs showed residual tumor in 27% of seminoma patients and 38% of non-seminoma patients. In seminoma patients, no viable cells were found in all six patients with pretreatment lactate dehydrogenase (LDH) levels below 7.5 times the upper limit of normal, or in all five of the patients with postchemotherapy RPLNs less than 2.5 cm. In non-seminoma patients, no viable cells were found in nine of 10 patients with pretreatment alpha-fetoprotein (AFP) levels less than 2700 ng/mL, or in eight of nine patients with residual mass less than 2.5 cm. CONCLUSIONS: Both postchemotherapy RPLN mass size and pretreatment tumor marker levels are possible predictors for necrosis of the residual mass in testicular cancer patients.  相似文献   
3.
 

Aims:


The purpose of this study is to examine the relationship between immunohistochemical localization of cathepsin D (CD), proliferating cell nuclear antigen (PCNA) and epidermal growth factor receptor (EGF-R) in 65 cases of breast carcinoma in Japanese women and traditional prognostic factors such as histological grade, lymph node status, mitotic rate and clinical stage, in order to possibly identify some indicator(s) that may be specifically associated with prognosis.  

Methods and results:


Serial sections of 5-μm thick were cut from the archival formalin-fixed, paraffin-embedded tissue blocks, and processed for CD, PCNA and EGF-R immunostaining. The results were analysed by computer-based image analysis system. All samples showed a positive immunoreaction for cathepsin D in both the parenchyma and stroma. However, the staining area and intensity varied from cell to cell in the parenchyma and stroma as well as among samples. Subsequently, the evaluation of immunostaining for CD was separately performed in both the parenchyma and stroma (CDpar and CDstr, respectively) and the combination of both components (CDtotal). PCNA and EGF-R showed positive immunostaining almost exclusively in the parenchymal component of the carcinoma tissue specimens. CDtotal significantly correlated with the histological grade, PCNA index (PI), mitotic rate (MR), EGF-R and lymph node metastasis. Significant correlation was also demonstrated between CDpar and the histological grade, EGF-R and lymph node metastasis, or between CDstr and MR, EGF-R and lymph node metastasis. EGF-R correlated highly with the histological grade, MR score, lymph node metastases and recurrence-free survival.  

Conclusions:


Both the CD parameters and EGF-R are valuable indicators for predicting the biological behaviour of human breast carcinoma.  相似文献   
4.
The aim of this study was to examine the effects of dietary fenofibrate (0.05% in the diet) on ketone body production and lipid secretion in isolated perfused rat liver. Feeding with fenofibrate for 7–9 days caused an increased liver weight. Ketone body production was significantly greater in the livers perfused with oleic acid than in those perfused without fatty acid, with the elevation of the ratio ofβ-hydroxybutyrate:acetoacetate indicating an increased redox potential in mitochondrial compartments by exogenous fatty acid. On the other hand, fenofibrate feeding caused a further stimulation of ketone body production from both endogenous and exogenous fatty acid substrates, respectively, with a decreased ratio ofβ-hydroxybutyrate:acetoacetate as compared to respective control livers, indicating a decreased redox potential. Hepatic secretion of triglyceride, but not of cholesterol, was decreased markedly in the fenofibrate-fed rats, especially when oleate was provided, suggesting an inverse relationship between rates of ketogenesis and triglyceride secretion. These results suggest that the altered hepatic metabolism of long-chain fatty acids between oxidation and esterification caused by fenofibrate may thus be a factor responsible for the decreased secretion of triglyceride, hence leading to hypotriglyceridaemiain vivo.  相似文献   
5.
The in-vitro permeability of chemically modified tetragastrin with fatty acids through the rat skin was studied. The permeability of these compounds through intact skin and stripped skin of rat was determined with a Franz-type diffusion cell. The permeation of tetragastrin across the intact skin was improved by chemical modification with acetic acid and butyric acid. However, tetragastrin and caproyl-tetragastrin did not permeate across the intact skin up to the end of experiment. The permeation of tetragastrin across the stripped skin was improved by chemical modification, the skin flux of these acyl derivatives being in the order: acetyl > butyroyl > caproyl. The stability of tetragastrin in skin homogenate was also significantly improved by chemical modification with fatty acids. These results suggest that chemical modification of tetragastrin with fatty acids increases its lipophilicity, which makes it permeable across the stratum corneum. Moreover, the chemical modification reduced the degradation of tetragastrin in the viable skin, resulting an increase in permeation of tetragastrin across the skin.  相似文献   
6.
Background: The direct effect of halothane on vascular smooth muscle is mediated in part via its effects on the sarcoplasmic reticulum (SR). Little information is available concerning the effects of other volatile anesthetics including isoflurane and sevoflurane, whose vascular effects differ from those of halothane. The aim of the present study was to compare the effects of halothane, isoflurane and sevoflurane on the SR by testing the contraction induced by caffeine in vascular smooth muscle. Methods: Rings without endothelium from isolated canine mesenteric artery were mounted in physiological saline solution (PSS) for isometric tension recording. After complete depletion of Ca2+ from the SR by adding 35 mM caffeine, the rings were exposed to normal Ca2+ containing PSS (Ca2+ loading), to Ca2+-free PSS for 10 min, and then to 15 mM caffeine to induce contraction. Anesthetics were administered during Ca2+ loading, the Ca2+-free phase and simultaneously with caffeine administration. Results: Halothane (0.5-2%) attenuated the caffeine-induced contraction of canine mesenteric artery when administered during Ca2+ loading in the SR (P<0.001), whereas isoflurane and sevoflurane (1–4%) failed to affect the contraction. When given simultaneously with caffeine, halothane (1–2%) potentiated the caffeine-induced contraction (P<0.05), but isoflurane and sevoflurane had no effect. When given before caffeine administration, halothane (0.5-2%), isoflurane (24%) and sevoflurane (4%) all potentiated the caffeine-induced contraction (P<0.05). Conclusion: It has been shown that halothane not only potentiates caffeine- induced Ca2+ release from the SR, but also induces contraction by releasing Ca2+ from the SR. We conclude that halothane decreases Ca2+ accumulation in the SR while exerting facilitative and additive effects on caffeine-induced Ca2+ release from the SR when applied before caffeine administration and simultaneously with caffeine, respectively, whereas isoflurane and sevoflurane lack both the ability to decrease Ca2+ accumulation and an additive effect on caffeine-induced Ca2+ release from the SR, but are able to facilitate Ca2+ release by caffeine.  相似文献   
7.
Background and Aims:  Increased numbers and enhanced functions of peripheral neutrophils have been observed in obstructive jaundice. However, the effects of obstructive jaundice on the bone marrow, that is neutrophil production and acquisition of neutrophil chemotactic activity, have been poorly understood. In the present study, differentials of bone marrow cells and chemotactic activity of bone marrow neutrophils were evaluated in bile duct-obstructed rats.
Methods:  Male Wistar rats underwent either bile duct obstruction for 10 days or bile duct obstruction for 4 days followed by 6 days' internal biliary drainage. Differentials of peripheral blood and bone marrow cells were sequentially determined. Chemotactic activity of peripheral and bone marrow neutrophils was evaluated with a modified Boyden method using interleukin-8 (recombinant rat Gro-β) as a chemoattractant.
Results:  Numbers of peripheral neutrophils significantly increased after bile duct obstruction. Significant increases in the myeloid/erythroid (M/E) ratio of bone marrow cells were observed after bile duct obstruction. The neutrophil proliferative pool (promyelocytes and myelocytes) increased initially, followed by an increased neutrophil storage pool (metamyelocytes, bands, and segmented neutrophils). The M/E ratio as well as the neutrophil proliferative and storage pools normalized after internal biliary drainage. Chemotactic activity was enhanced in both peripheral and bone marrow neutrophils after bile duct obstruction, and enhanced chemotaxis was alleviated with internal biliary drainage.
Conclusion:  The present results strongly suggest the principal role of the bone marrow in increasing the number of neutrophils and their chemotactic activity during obstructive jaundice.  相似文献   
8.
The postprandial effect on the bioavailability of bropirimine in dogs after oral administration of bropirimine tablets (Bropirimine 250 mg Tablet) was investigated. At a dose of 500 mg bropirimine (two tablets of bropirimine 250 mg), the maximum plasma concentration under the postprandial condition was about twice that observed under the fasting condition, and the area under the plasma concentration vs time curve under the postprandial condition was also twice that under the fasting condition. The absolute oral bioavailabilities of bropirimine were 41.1% under the fasting condition and 83.5% under the postprandial condition. It is considered that the longer gastric residence time and larger volume of the gastric fluid induced by food-intake caused the increase in dissolution of bropirimine which increased the bioavailability after oral dosing of bropirimine 250-mg tablets.  相似文献   
9.
This study was conducted to elucidate the mechanisms of action of two Chinese traditional drugs, Oren-gedoku-to and Unsei-in, which have been used for many years in the treatment of inflammatory disorders. In rats with acetic acid-induced inflammation, both drugs reduced interleukin-8 concentrations in the serum. Neither drug significantly affected superoxide dismutase activity in the serum, although Unsei-in increased superoxide dismutase activity in liver after 1 month of administration. Oren-gedoku-to showed no significant effect on liver superoxide dismutase activity. It was considered that these medicines exert their anti-inflammatory effects mainly on the early stages of inflammation, wherein increased capillary permeability and migration of leucocytes occur.  相似文献   
10.
Abstract Daan's two process model is known to be one of the most powerful models, covering various situations from free-running to sleep deprivation. In this study, bifurcation properties of the model dynamics as function of a gap, D , between the threshold processes are clarified using a circle map. As a function of D , we will show that the model has the different types of the mutual entrainment regions that are intervened by the tangent bifurcation. The variable behavior of human circadian rhythm is suggested to be systematically understood based on the bifurcation properties of the two process model.  相似文献   
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