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51.
52.
Well‐differentiated papillary mesothelioma (WDPM) is a distinct subtype of mesothelial tumor from diffuse malignant mesothelioma (DMM), with an uncertain malignant potential. The relationship between WDPM and DMM, with regard to the ability of the former to develop into the latter, is also unknown. A 58‐year‐old woman, diagnosed with a rectal carcinoid tumor, underwent removal of the lymph nodes via the abdomen in 2004. A large number of white miliary nodules were identified on the mesentery and peritoneum, which were histologically diagnosed as WDPM. No further therapy was administered, but the patient was followed‐up using imaging methods. Seven years later, an abdominal wall mass was discovered using positron emission tomography‐computed tomography, and a laparotomy biopsy was performed. DMM was diagnosed, because mesothelioma with extended invasion had been histologically identified. Mesothelioma similar to papillary proliferation was present on the outer layer of the peritoneum, and an infiltrating lesion with continuous restiform or solid‐like structures was noted. WDPM was believed to have undergone malignant transformation. Compared to DMM, WDPM has a good prognosis and is considered a benign or borderline neoplasm. Our findings suggest that WDPM does have malignant potential, however, because histological findings indicated a malignant transformation of WDPM to DMM.  相似文献   
53.
Two monkeys (Macaca fascicularis) each were infected with dengue virus type 1 (DENV-1) and type 2 (DENV-2). High levels of neutralizing antibody to homotypic serotype were detected from day 10 to week 58 after infection. Levels of cross-reactive neutralizing antibody to other serotypes were at lower levels or undetectable. Serum samples collected from day 10 to week 58 enhanced infection by homotypic and heterotypic serotypes of DENV when diluted, demonstrating antibody-dependent enhancement (ADE). The ADE activities to heterotypic and homotypic dengue virus infections peaked at dilutions of 1:10–1:100 and 1:100–1:1,000, respectively. Serum samples collected enhanced heterotypic dengue virus infection without any dilution. The results indicate that sera from infected monkeys have an ability to enhance heterotypic dengue virus infection in vitro without dilution, although some of these sera also possess neutralizing activity.  相似文献   
54.
A case of malignant mixed mullerian tumor of the ovary in a 57 year old woman is reported along with the results of an immunohistochemical study. The tumor, measuring 16·10·9cm, was composed predominantly of adenocarcinoma with a smaller amount of anaplastic carcinoma as an epithelial component and chondrosarcoma, liposarcoma, fibrosarcoma and rhabdomyoblasts as mesenchymal elements. Immunohistochemistry using paraffin sections demonstrated cytokeratin (CK) and epithelial membrane antigen (EMA), generally regarded as epithelial markers, not only in the epithelial component but also in chondrosarcoma cells. Vimentin and desmin, generally regarded as mesenchymal markers, were exhibited partly in carcinoma cells as well as in mesenchymal elements. Positive staining for S 100 protein was obtained not only in chondrosarcoma and liposarcoma cells, but also partly in adenocarcinoma cells. This intricate immunohistochemical picture reflected the histologic findings. It is noteworthy that both carcinoma cells and chondrosarcoma cells demonstrated simultaneous expression of CK, EMA, vimentin, desmin and S 100 protein. This somewhat unusual antigen expression by tumor cells may indicate a change in the nature of tumor cells due to microenvironmental factors. Acta Pathol Jpn 40: 845 850, 1990.  相似文献   
55.
In order to study the biological activity of endogenous digitalis-like substance (DLS) and Na-K-ATPase inhibitor (ATPI), human urine was partially purified and administered to rats, and its effects on the urinary volume, urinary Na excretion and blood pressure (BP) were determined. In addition, the effect on myocardial Na-K-ATPase activity was also measured. After the extraction of 40L of urine with a reversed phase cartridge column (S-fraction), 20 ml of chloroform was added and extraction was repeated. The chloroform layer was applied to an open silica gel column, and at a fraction with ethylacetate: methanol (60: 40, T-1 fraction), DLS and ATPI were eluted at the highest concentration. The water layer was treated with charcoal (D-1 fraction). The acute administration of K-1, T-1 fraction to rats in vivo caused significant rises in urinary volume, urinary Na excretion and BP. In chronic administration of K-1 fraction, urinary Na excretion was significantly elevated and myocardial Na-K-ATPase activity was also significantly suppressed. These results suggest that DLS and ATPI cause increase in the urinary volume and urinary Na excretion and also possess a hypertensive action; and moreover, these substance may affect the heart like cardiotonic steroids and regulate BP by increasing cardiac contractility.  相似文献   
56.
Schizophrenia is considered as a “neurodegenerative” and “neurodevelopmental” disorder, the pathophysiology of which may include hypofunction of the N‐methyl‐d ‐aspartate receptor (NMDA‐R) or subsequent pathways. Accordingly, administration of NMDA‐R antagonists to rodents during the perinatal period may emulate some core pathophysiological aspects of schizophrenia. The effect of 4‐day (postnatal day; PD 7–10) administration of MK‐801, a selective NMDA‐R antagonist, on gene expression in the medial prefrontal cortex (mPFC), hippocampus, and amygdala was evaluated using quantitative polymerase chain reaction methods. Specifically, we sought to determine whether genes related to Glu transmissions, for example those encoding for NMDA‐Rs, metabotropic Glu receptors (mGluRs), or Glu transporters, were altered by neonatal treatment with MK‐801. Model rats showed downregulation of the mGluR3 subtype in the mPFC around puberty, especially at PD 35 in response to MK‐801 or during ontogenesis without pharmacological manipulations. Genes encoding for other mGluRs subtypes, that is NMDA‐Rs and Glu transporters, were not affected by the neonatal insult. These results suggest that NMDA‐R antagonism in the early course of development modulates the expression of mGluR3 in mPFC around puberty. Thus, mGluR3 may serve as a potential target to prevent the onset and progression of schizophrenia. Synapse 68:202–208, 2014 . © 2014 Wiley Periodicals, Inc.  相似文献   
57.
Background Traditionally, dermatophytosis, a common disease affecting millions of people world‐wide, has been diagnosed by direct microscopy and fungal culture. The immunochromatography (ICG) strip test was recently developed. Methods We compared the performance of the ICG strip test for the detection of dermatophytes in samples from human skin and nails with direct microscopy. The 160 samples, consisting of 88 skin and 72 nail specimens, were subjected to direct microscopy study using a 20% KOH solution and to examination with the ICG strip test. Of 160 samples, 18 were examined by fungal culture using Sabouraud dextrose agar medium. Results We found that the overall sensitivity and specificity of the ICG test were 83.5% and 66.7%; they were 82.1% and 76.2% for the 88 skin and 85.4% and 58.3% for the 72 nail specimens, respectively. Conclusions Our findings indicate that the efficacy of the ICG test is comparable to direct microscopy for the detection of dermatophytes. Performance of the assay was easy, and results were available quickly. We suggest that it is an effective tool for dermatophytosis screening.  相似文献   
58.

Purpose

To retrospectively evaluate whether the mean, minimum, and maximum apparent diffusion coefficient (ADC) of glioblastomas obtained from pretreatment MR images is of prognostic value in patients with glioblastoma.

Materials and methods

The institutional review board approved our study and waived the requirement for informed patient consent. Between February 1998 and January 2006, 33 patients (24 males, 9 females; age range 10-76 years) with supratentorial glioblastoma underwent pretreatment magnetic resonance (MR) imaging. The values of the mean, minimum, and maximum ADC (ADCmean, ADCMIN, and ADCMAX, respectively) of each tumor were preoperatively determined from several regions of interest defined in the tumors. After surgical intervention, all patients underwent irradiation and chemotherapy performed according to our hospital protocol. The patient age, symptom duration, Karnofsky performance scale score, extent of surgery, and ADC were assessed using factor analysis of overall survival. Prognostic factors were evaluated using Kaplan-Meier survival curves, the log-rank test, and multiple regression analysis with the Cox proportional hazards model.

Results

Likelihood ratio tests confirmed that ADCMIN was the strongest among the three prognostic factors. Total surgical removal was the most important predictive factor for overall survival (P < 0.01). ADCMIN was also statistically correlated with overall survival (P < 0.05) and could be used to classify patients into different prognostic groups. Interestingly, ADCMIN was also the strongest prognostic factor (P < 0.01) in the group of patients in whom total tumor removal was not possible.

Conclusion

The ADCMIN value obtained from pretreatment MR images is a useful clinical prognostic biomarker in patients with glioblastoma.  相似文献   
59.
BACKGROUND: We investigated retrospectively the relationship between the intrathecal dose of 0.5% hyperbaric bupivacaine and the use of 2% mepivacaine through an epidural catheter. METHODS: Forty-nine patients undergoing cesarean section with combined spinal and epidural anesthesia (CSEA) were analyzed. They were divided into two groups; with (CSEA group) and without additional epidural injection group (spinal group). RESULTS: In the CSEA group (24 patients received 1.2 +/- 0.4 ml of 0.5% hyperbaric bupivacaine), 5-10 ml of 2% mepivacaine were required to achieve the adequate surgical anesthesia. In the spinal group (25 patients received 1.6 +/- 0.3 ml of 0.5% hyperbaric bupivacaine), cesarean section was performed without additional mepivacaine before delivery. The analgesic level and the amount of fluid infusion were similar in the two groups. However, 20% of patients in the spinal group showed hypotension (systolic blood pressure below 80 mmHg), although no patients in the CSEA group developed hypotension. The amount of ephedrine used before delivery was significantly larger in the spinal group (8.9 +/- 7.7 mg) than in the CSEA group (3.9 +/- 4.3 mg). CONCLUSIONS: Spinal anesthesia induced by 1.2 ml of 0.5% hyperbaric bupivacaine with sequential epidural block induced by 5-10 ml of 2% mepivacaine caused no hypotension during cesarean section.  相似文献   
60.
Background: The local anesthetic lidocaine affects neuronal excitability in the central nervous system; however, the mechanisms of such action remain unclear. The intracellular sodium concentration ([Na+]i) and sodium currents (INa) are related to membrane potential and excitability. Using an identifiable respiratory pacemaker neuron from Lymnaea stagnalis, the authors sought to determine whether lidocaine changes [Na+]i and membrane potential and whether INa is related to these changes.

Methods: Intracellular recording and sodium imaging were used simultaneously to measure membrane potentials and [Na+]i, respectively. Measurements for [Na+]i were made in normal, high-Na+, and Na+-free salines, with membrane hyperpolarization, and with tetrodotoxin pretreatment trials. Furthermore, changes of INa were measured by whole cell patch clamp configuration.

Results: Lidocaine increased [Na+]i in a dose-dependent manner concurrent with a depolarization of the membrane potential. In the presence of high-Na+ saline, [Na+]i increased and the membrane potential was depolarized; the addition of lidocaine further increased [Na+]i, and the membrane potential was further depolarized. In Na+-free saline or in the presence of tetrodotoxin, lidocaine did not change [Na+]i. Similarly, hyperpolarization of the membrane by current injections also prevented the lidocaine-induced increase of [Na+]i. In the patch clamp configuration, membrane depolarization by lidocaine led to an inward sodium influx. A persistent reduction in membrane potential, resulting from lidocaine, brings the cell within the window current of INa where sodium channel activation occurs.  相似文献   

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