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1.
We evaluated twenty renal transplant subjects at various stages of BKV nephritis (BKVN) for BKV-specific IgG and IgM antibodies using ELISA technique and BKV-DNA using PCR. They were divided as early onset (n = 7), stabilizing (n = 3), resolved (n = 8) and late onset (n = 2) BKVN. BKV-specific antibodies and BKV-DNA were simultaneously determined. The mean BKV-specific IgG level in early onset and stabilizing BKVN were 64 and 39 EIA units, and were significantly lower than 138 EIA units seen in resolved BKVN, P = 0.007, P = 0.008. The mean BKV-specific IgM levels in stabilizing BKVN was higher than resolved BKVN (130 vs 51 EIA units), P = 0.006. Mean plasma BKV loads for each group were 955,925, 5642 and 42 copies/mL of plasma, respectively. Prospective study in six BKVN cases revealed mean IgG, IgM levels and BKV-DNA at the time of diagnosis of BKVN as 39, 110 EIA units and 586,758 copies/mL of plasma, respectively. After a mean period of 5.2 months, IgG level increased to 120 EIA units (p = 0.0058) and had no detectable viral copies in circulation. Recovery from BKVN and elimination of BKV is associated with the development of BKV-specific IgG antibodies and this provides insight into the role of humoral immunity to BKV in the pathogenesis of BKVN.  相似文献   
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In the present study, electrical stimulation of medical or laternal septal areas and total or restricted lesions of these were conducted to observe the effect on ingestion of primary taste solutions in a free-choice situation. Stimulation induced a specific decrease in the intake of NaCl solution and had no effect on saccharin, acetic acid and quinine solutions and water. Total septal lesion or restricted lesions of medial or lateral septal areas induced hyperdipsia in rats. The lesioned rats, in a free-choice situation preferred NaCl, saccharin, as well as acetic acid solutions. This increase in acetic acid intake after lesion suggests that sour taste is also affected. Furthermore, there was no consumption of quinine solution before and after the lesion. This might be due to the presence of sweet tasting saccharin solution in this free-choice situation. These results indicate that the septal area causes aversion to NaCl intake, probably by inhibiting lateral hypothalamic neurons responsible for NaCl ingestion. The consumption of large quantities of saccharin, NaCl and acetic acid after the septal lesion suggests that the rats become overresponsive to taste factors in a free-choice situation.  相似文献   
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The adaptive response is an error-free DNA repair mechanism induced by low levels of physical or chemical agents. Cells pre-exposed to such agents are resistant to genetic damage induced by subsequent treatment at a high dose. There are many reports on such adaptive responses. Recently we have shown the existence of adaptive responses in vivo in the grasshopper Poecilocerus pictus and the mouse and in vitro in human lymphocytes. Different enzymes are implicated in this DNA repair pathway. In an attempt to understand the molecular mechanism of the methyl methanesulfonate (MMS)-induced adaptive response, the present investigations have been undertaken employing nicotinamide, an inhibitor of the DNA repair enzyme poly(ADP-ribose) polymerase (PARP). Pre-, inter- and post-treatments with nicotinamide of MMS-treated mouse bone marrow cells were carried out. The results revealed that there is a significant reduction in the frequency of chromosomal aberrations compared with combined treatment, suggesting an enhancement of the adaptive response by nicotinamide. Further, the results of NAD+ assay in the inter-treatment experiment showed that there is no depletion of NAD+. Thus, it can be stated that PARP is not involved in the MMS-induced adaptive response in mouse bone marrow cells.  相似文献   
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Intraventricular tuberculous abscess: a case report   总被引:1,自引:0,他引:1  
Ventricles can be involved in different ways in neurotuberculosis, however, the occurrence of intraventricular abscess has been rarely reported. We report a young woman who had intraventricular tubercular abscess. Cranial computed tomographic scan showed hypodense ring enhancing lesion in the right lateral ventricle with unilateral hydrocephalus. She underwent parasagittal craniotomy with total excision of the lesion. The pus obtained from the lesion was teeming with acid fast bacilli.  相似文献   
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Accurate determination of left ventricular (LV) volume has important therapeutic and prognostic implications in patients with cardiac disease. Volume estimations by two-dimensional techniques are not very accurate due to geometric assumptions. OBJECTIVES: To validate LV volume determinations by a new transesophageal three-dimensional echocardiographic technique. We performed three-dimensional reconstruction of the LV using an echo-computed tomographic (CT) technique based on serial pullback parallel slice imaging technique in both in vitro and in vivo settings. Fourteen latex balloons with various sizes (30-235 mL) and shapes (conical, pear shaped, round, elliptical, and aneurysms in various locations) filled with known volumes of water were imaged in a water bath. From the static three-dimensional image, the LV long axis was defined and the LV was sectioned perpendicular to this axis into 2-mm slices. The volume of each slice was calculated with the observer blinded to the actual volume as the product of the slice thickness and the manually traced perimeter of the slice and the LV volume as the sum of the volumes of the slices (Simpson's method). The calculated LV volume closely correlated with the actual volume (r = 0.99, P < 0.0001, calculated volume = 1.06x - 11.3, Deltavolume = -5.7 +/- 10.0 cc). Using the same system, transesophageal echocardiographic (TEE) images of the LV were obtained in 15 patients gated to respiration and ECG. Satisfactory dynamic three-dimensional reconstruction of the LV was possible in ten patients. The three-dimensional LV volumes (systolic and diastolic) using Simpson's method correlated well with those obtained from biplane or multiplane TEE images using the area length method (r = 0.89, p < 0.0001, y = 12.7 + 0.84x, Deltavolume = 1.3 +/- 18.1 cc). The LV major-axis diameters by the two methods showed very close correlations as well (r = 0.86, P < 0.0001, y = 19 + 0.74x, Deltadiameter = 1.0 +/- 7.2 mm). We conclude that three-dimensional LV volume calculation by the echo-CT technique is intrinsically sound, is independent of LV geometry, and with some limitations, is applicable in vivo. (ECHOCARDIOGRAPHY, Volume 13, November 1996)  相似文献   
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Superior vena cava (SVC) syndrome is a well-recognized clinical entity seen with mediastinal malignancies and intraluminal venous thrombosis. The role of recombinant tissue plasminogen activator (rt-PA) in the resolution of SVC syndrome caused by thrombosis in the bone marrow transplant settings has not been described. The authors report a case of SVC syndrome with good clinical response in a 16-year-old female with sickle cell disease undergoing an allogeneic bone marrow transplant (BMT) from her HLA identical sibling. Shortly after her transplant, she was found to have significant facial edema and swelling above the neck. Concomitantly, her renal function deteriorated with progressive elevation of serum urea nitrogen and creatinine levels, requiring the use of continuous veno-venous hemofiltration. An upper extremity venogram showed complete SVC obstruction (type III) with apparent inferior reflux into the azygos system. rt-PA was started at a dose of (0.5 mg/kg/day) for 2 days. There was a dramatic resolution of her symptoms, including significant improvement in renal function with increase in urine output. A repeat venogram showed free flow from the distal tip of the central line consistent with a patent superior vena cava. There was no evidence of any bleeding manifestations with rt-PA. This report highlights the usefulness of rt-PA as a treatment modality for SVC syndrome in the BMT settings.  相似文献   
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