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101.
The efficient and complete filtration of blood plasma is one of the most important functions of the kidneys. Proteinuria is the pathological occurrence of protein molecules in urine due either to increased filtration in the glomerulus or to increased secretion or inefficient resorption in the tubules. The latter represents the least common cause of increased protein excretion. In this article the four different components of the glomerular filter, glycocalyx, fenestrated endothelial cells, basement membrane and epithelial podocytes with foot processes and slit membrane, will be briefly characterized and examples of albuminuria and proteinuria will be discussed.  相似文献   
102.
Behavioral studies suggest that preference for a beat rate (tempo) in auditory sequences is tightly linked to the motor system. However, from a neuroscientific perspective the contribution of motor‐related brain regions to tempo preference in the auditory domain remains unclear. A recent fMRI study (Kornysheva et al. [ 2010 ]: Hum Brain Mapp 31:48‐64) revealed that the activity increase in the left ventral premotor cortex (PMv) is associated with the preference for a tempo of a musical rhythm. The activity increase correlated with how strongly the subjects preferred a tempo. Despite this evidence, it remains uncertain whether an interference with activity in the left PMv affects tempo preference strength. Consequently, we conducted an offline repetitive transcranial magnetic stimulation (rTMS) study, in which the cortical excitability in the left PMv was temporarily reduced. As hypothesized, 0.9 Hz rTMS over the left PMv temporarily affected individual tempo preference strength depending on the individual strength of tempo preference in the control session. Moreover, PMv stimulation temporarily interfered with the stability of individual tempo preference strength within and across sessions. These effects were specific to the preference for tempo in contrast to the preference for timbre, bound to the first half of the experiment following PMv stimulation and could not be explained by an impairment of tempo recognition. Our results corroborate preceding fMRI findings and suggest that activity in the left PMv is part of a network that affects the strength of beat rate preference. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
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PURPOSE: Recombinant interferon alfa-2b (rIFNalpha2b) is a standard therapy for chronic myelogenous leukemia (CML). Severe neuropsychiatric toxicity has been described in patients receiving rIFNalpha2b, although the frequency of and the risk factors for developing this toxicity are not well described. The purpose of this study was to identify predictors for the development of severe neuropsychiatric toxicity in CML patients receiving rIFNalpha2b-based therapy. PATIENTS AND METHODS: From a prospective cohort of 91 Philadelphia chromosome-positive, previously untreated, chronic-phase CML patients treated on Cancer and Leukemia Group B (CALGB) 9013, a phase II trial of rIFNalpha2b plus cytarabine, the following were recorded at baseline: age, sex, race, pretreatment history of neurologic or psychiatric diagnosis, spleen size, blood counts, and peripheral blast count. Best response to treatment, rIFNalpha2b cumulative dose, dose duration, and dose-intensity were recorded during follow-up. Severe neuropsychiatric toxicity was defined as grade 3 or 4 events, according to CALGB expanded common toxicity criteria. Univariate and multivariate logistic regression analyses were used to identify variables that were associated with the development of severe neuropsychiatric toxicity. RESULTS: Severe neuropsychiatric toxicity developed in 22 patients (24.0%; 95% confidence interval [CI], 15.2% to 32.8%). Toxicity resolved after withdrawal of treatment in all patients. Five of six patients developed recurrence of symptoms with rechallenge. Twelve (63%) of 19 patients with a pretreatment neurologic or psychiatric diagnosis developed severe neuropsychiatric toxicity, as compared with 10 (14%) of 72 patients without a pretreatment neurologic or psychiatric diagnosis (P =.001), resulting in a relative risk of 4. 55 (95% CI, 2.33 to 8.88) for developing severe neuropsychiatric toxicity. No other variables were independently associated with the development of neuropsychiatric toxicity. CONCLUSION: CML patients with a pretreatment history of a neurologic or psychiatric diagnosis are at significantly increased risk of developing severe neuropsychiatric toxicity during therapy with rIFNalpha2b plus cytarabine. Monitoring for neuropsychiatric symptoms and avoiding rechallenge are recommended measures for such patients receiving rIFNalpha2b-based therapy.  相似文献   
105.
The National Cancer Institute (NCI) sponsored a workshop to develop a set of standardized diagnostic and response criteria for acute myeloid leukemia (AML) clinical trials. The French-American-British (FAB) classification was retained for diagnosing AML, with the addition of patients with bone marrow morphologic features of a myelodysplastic syndrome and less than 30% bone marrow blasts, but with greater than or equal to 30% blasts in the peripheral blood. In this report, there are four important subgroups of AML not defined in the FAB classification that are discussed: undifferentiated acute leukemia, MO (AML lacking definitive myeloid differentiation by morphology or conventional cytochemistry but with ultrastructural or immunophenotypic evidence for AML), mixed lineage leukemia, and hypocellular AML. Definitions of response for clinical trials are presented to facilitate comparisons among different studies. Complete remission is considered the only response worth reporting in phase III trials, since lesser responses do not improve survival. Partial remissions may be of interest to identify active new agents in phase I and II studies. Monoclonal antibodies and cytogenetic studies are not part of the routine assessment of remission or reassessment at relapse, and their role in the evaluation of patients with AML is currently being evaluated in clinical trials. Although we recognize that some of the definitions in this report are arbitrary, generalized use of these guidelines will make results of clinical trials more comparable and interpretable.  相似文献   
106.
Glial reaction has been studied in the rat by the immunohistochemical demonstration of glial fibrillary acidic protein (GFAP) and vimentin (VIM) in two experimental conditions. The first was represented by a necrotic cerebral lesion obtained by laser irradiation and the second by the development of experimental tumors induced by transplacental ethylnitrosourea. Reactive astrocytes develop not only in the proximity of the lesion but also distant from it. The intensity of the glial response seems to depend upon the normal distribution of astrocytes and the perilesional edema. GFAP decorates all the reactive astrocytes, whereas VIM is positive only in those at the edges of the lesion. The significance of the different responses in the two models and between the two intermediate filaments is discussed.  相似文献   
107.
E J Lee  K Reck  C A Schiffer 《Leukemia》1990,4(3):189-192
Diaziquone (AZQ) and etoposide (VP-16) were administered as simultaneous 5-day continuous infusions to 27 patients with acute leukemia (22 with acute myeloid leukemia (AML), three with chronic myeloid leukemia in blast crisis (CML-B), and two with acute lymphocytic leukemia) at four different doses in a phase I trial. Gastrointestinal toxicity, primarily stomatitis, was dose limiting, occurring in six of 10 patients at the highest dose level. Diarrhea was the only other grade 3 toxicity noted (three of 10 at the highest dose level). The duration of bone marrow aplasia was excessive at the highest dose (median 48 days to granulocytes greater than 500/mm3, range 33-67) but acceptable (31 days) at the maximum tolerated dose: AZQ 28 mg/m2/day x 5 days, VP-16 150 mg/m2/day x 5 days. Complete remissions were seen in seven patients (six AML, one CML-B) and a partial remission in one patient with AML. The median duration of unmaintained complete remission was 3 months (range 1.5-26+).  相似文献   
108.
Literature findings on astrogliosis of the spinal cord and of the cortex of sporadic (SALS) and familial (FALS) cases of amyotrophic lateral sclerosis (ALS) and of SOD1 transgenic mice are analysed and compared with those of 50 autopsied personal cases of ALS. In the spinal cord, astrogliosis is definitely evident in the anterior horns and much less in anterior and lateral funiculi and dorsal horns. In the cortex reactive astrocytes show a distribution similar to that of ageing brains and in ischaemia and cannot be directly put in relation with neuronal loss. In the spinal cord of transgenic mice the evidence suggests a primary astrocytic response. The findings in human ALS, especially those of the cortex, are consistent with this hypothesis.  相似文献   
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