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91.
CD5, CD10, and CD23 are cell surface antigens used to distinguish B-cell disorders. The expression of these antigens and their clinical significance in Waldenstrom's macroglobulinemia (WM), an uncommon B-cell disorder, remains to be clarified. We therefore determined expression of CD5, CD10, and CD23 by flow cytometric analysis on bone marrow lymphoplasmacytic cells (CD19+ k/l light chain restricted) for 171 serially biopsied patients with findings of the consensus panel definition of WM. Importantly, we also correlated laboratory and clinical data, as well as existence of a familial history of a B-cell disorder in view of reports suggesting familial predisposition in WM. These studies demonstrated tumor cell expression of CD5, CD10, and CD23 in 15 of 171 patients (9%), 11 of 161 patients (7%), and 37 of 105 patients (35%), respectively. Coexpression of CD23 with CD5 or CD10 was common. Tumor Lymphoplasmacytic from 10 of 15 (66%) and 3 of 11 (27%) patients with WM that expressed CD5 and CD10, respectively, also showed expression of CD23 (P = 0.01 and P = 0.08, respectively). Among patients with CD23 expression, increased serum immunoglobulin (Ig) M levels were observed compared with patients without CD23 expression (P = 0.05). No differences in age at diagnosis; presence of adenopathy and/or splenomegaly; bone marrow involvement; serum IgA, IgB, and b2 macroglobulin levels; hematocrit; platelet count; or familial history of WM or a related B-cell disorder were observed among patients with and without CD5, CD10, and CD23 expression. These studies demonstrate that CD5, CD10, and CD23 are commonly found in WM and that their expression should not exclude the diagnosis of WM. Moreover, expression of CD23 may define a clinically distinct subset of patients with WM.  相似文献   
92.
93.
The objective of this study was to analyze the usefulness of the Brazilian Hospital Information System (SIH) in comparison to medical records to study factors associated with in-hospital mortality due to acute myocardial infarction (AMI). We evaluated a stratified random sample of 391 medical records (out of 1,936 hospital admissions forms) with AMI as the primary diagnosis in the city of Rio de Janeiro. Factors associated with in-hospital death were studied through logistic modeling. Models were developed directly from the SIH and from medical records. ROC curves were constructed to allow comparison of the different models. We found an AMI diagnostic confirmation = 91.7% and hospital mortality = 20.6%. The logistic model derived from medical records produced the best fit (concordance = 90.1%). Although the SIH model had a worse fit (concordance = 70.6%), the correction of keying-in and information errors using data from medical records did not significantly modify its performance. Under-recording of secondary diagnosis was high in the SIH forms and was the main limiting factor.  相似文献   
94.
Fingerlings of the silver catfish (Rhamdia quelen) were exposed to three herbicides widely used in rice culture in south Brazil: clomazone, quinclorac, and metsulfuron methyl. LC50 was determined and acetylcholinesterase (AChE) activity was evaluated in brain and muscle tissue of fish exposed to different herbicide concentrations after 96h (short term). The LC50 value (nominal concentration) was 7.32 mg/L for clomazone and 395 mg/L for quinclorac, but was not obtained for metsulfuron-methyl since all fingerlings survived the highest concentration of 1200 mg/L. Brain and muscle AChE activity in unexposed fish were 17.9 and 9.08 micromol/min/g protein, respectively. Clomazone significantly inhibited AChE activity in both tissues, achieving maximal inhibition of about 83% in brain and 89% in muscle tissue. In contrast, quinclorac and metsulfuron methyl caused increases in enzyme activity in the brain (98 and 179%, respectively) and inhibitions in muscle tissue (88 and 56%, respectively). This study demonstrated short-term effects of exposure to environmentally relevant concentrations of rice field herbicides on AChE activity in brain and muscle tissue of silver catfish.  相似文献   
95.
BACKGROUND: There is little information regarding the 12-h mycophenolic acid (MPA) pharmacokinetics (PK), a way to monitor the drug and the need of frequent monitoring, in stable patients. METHODS: A cohort of 35 adults, under long-term mycophenolate mofetil (MMF) therapy plus cyclosporin A (n = 12), TACimus (n = 12) or MMF only (n = 11); all with prednisone had a 12-h MPA-PK performed to ascertain the percentage of them within a defined therapeutic window. In 13 other patients, two PK studies undergone 1 wk apart were performed to evaluate the need for frequent measurements. RESULTS: Fourteen (40%) patients were within the defined therapeutic window (36-60 microg h/mL). Nine patients (26%) were overexposed while 12 (34%) were underexposed. A Cmax> or =10 microg/mL was seen in 20 (57%) of the patients. These percentages were equally distributed between the treatment groups both for AUC0-12 and Cmax. The equations using C0, C2 or both predict exposure, although the use of C2 seems to be more adequate in clinical practice. There were no differences in MPA exposure in patients with a repeated PK evaluated 1 wk later. CONCLUSION: The use of MMF without monitoring MPA blood levels may cause over-/underexposure to the drug in stable recipients. However, in patients under MMF for more than 1 yr, MPA levels are stable and there is no need for frequent measurements.  相似文献   
96.
BACKGROUND: The therapeutic options to treat Alzheimer-type dementia (ATD) in recent years, have made it increasingly necessary to become familiar with the employment pattern of these new medicinal products. METHODS: A cross-sectional observational study of the population with ATD treated with acetylcholinesterase inhibitors and/or memantine in the Gallician Health Service. Databases were compiled with the demographic variables and use data during April 2005 of the medicinal products studied. RESULTS: Of the 5110 patients with ATD, 70.47% were women. The mean age of the women was 80.12 and of the men was 78.61 years old, with standard deviations of 6.66 and 7.03, respectively. The female sex was one of the factors associated with presenting ATD to pharmacological treatment (OR: 1.932 [CI 95%: 1.819-2.052]). The medication used most was donepezyl (44.46% of patients). Significant differences were found in that memantine was used to treat more patients in the group of patients < or =64 years (19.7% in < or =64 years vs. 14% in >64 years [p < 0.05]), and donepezyl was preferentially used in patients > or =95 years (75% in > or =95 years vs. 46.9% in <95 years [p < 0.03]). No significant differences were observed in the use of anti-dementia therapy, expressed in DDD/patient/day between the sexes, age groups, or in the age groups separated according to sex. CONCLUSIONS: The use of memantine (in monotherapy or in combination) is more frequent in patients under 64 years old. Female sex was found to be a factor associated with presenting ATD to pharmacological treatment.  相似文献   
97.
98.
Oral and intraperitoneal administration of the nucleoside guanosine have been shown to prevent quinolinic acid- (QA) and alpha-dendrotoxin-induced seizures, impair memory, and impair anxiety in rats and mice. We investigated the effect of 2-weeks ad lib orally administered guanosine (0.5 mg/ml) on seizures induced by QA, inhibitory avoidance memory, and locomotor performance in rats. We also studied the mechanism of action of guanosine through the measurement of its concentration in the cerebrospinal fluid (CSF) and its effect on glutamate uptake in cortical slices of rats. QA produced seizures in 85% of rats, an effect partially prevented by guanosine (53% of seizures; P = 0.0208). Guanosine also impaired retention on the inhibitory avoidance task (P = 0.0278) and decreased locomotor activity on the open field test (P = 0.0101). The CSF guanosine concentration increased twofold in the treated group compared to that in the vehicle group (P = 0.0178). Additionally, QA promoted a 30% decrease in glutamate uptake as compared to that with intracerebroventricular saline administration, an effect prevented by guanosine in animals protected against QA-induced seizures. Altogether, these findings suggest a potential role of guanosine for treating diseases involving glutamatergic excitotoxicity such as epilepsy. These effects seem to be related to modulation of glutamate uptake.  相似文献   
99.
Apert syndrome is characterized by craniosynostosis, symmetric syndactyly and other systemic malformations, with mental retardation usually present. The objective of this study was to correlate brain malformations and timing for surgery with neuropsychological evaluation. We also tried to determine other relevant aspects involved in cognitive development of these patients such as social classification of families and parents education. Eighteen patients with Apert syndrome were studied, whose ages were between 14 and 322 months. Brain abnormalities were observed in 55.6% of them. The intelligence quotient or developmental quotient values observed were between 45 and 108. Mental development was related to the quality of family environment and parents education. Mental development was not correlated to brain malformation or age at time of operation. In conclusion, quality of family environment was the most significant factor directly involved in mental development of patients with Apert syndrome.  相似文献   
100.
Clinically non-functioning pituitary adenomas do not produce clinical signs of hormonal hypersecretion. Therefore, signs and symptoms will depend on the mass effect of these adenomas over the central nervous system. Their etiopathogeny is complex and their development is probably influenced by several factors, such as hypothalamic hormones (GHRH), growth factors (FGF), proliferation factors (PCNA, and KI-67), protein P53 and the proto-oncogene c-erb-B2. OBJECTIVE: 1) Determining the clinical features of a population of 117 patients treated for clinically non-functioning pituitary adenoma (age, sex, tumor size, number of surgical procedures, development of hormonal deficiency and hyperprolactinemia). 2) Identifying, after the patients had been clinically characterized, those with clinically non-functioning adenomas with positive immunohistochemistry for hypophyseal hormones (PRL, LH, FSH, GH, TSH and ACTH). 3) Determining if the immunohistochemistry of this population was positive for the cellular proliferation factor Ki-67, protein P53 and protein C-erb-B2 and establishing a correlation with tumor size and tumor invasiveness. This will help in the evaluation of the prognostic value of these proliferation factors. 4) Confronting the results of immunohistochemistry using a standard block with the results of immunohistochemistry using a tissue micro-array. METHOD: Study of the clinical features of 117 patients with clinically non-functioning pituitary adenoma (age, sex, tumor size, number of surgical procedures, development of hormonal deficiency and hyperprolactinemia). Immunohistochemical study (H&E) of 39 patients for hypophyseal hormones, protein P53, protein C-erb-B2, Ki-67 to establish their correlation to tumor growth. The next step was a tissue micro-array of the 39 previously studied cases, using immunohistochemistry for hypophyseal hormones, protein P 53, protein C-erb-B2, Ki-67 to establish their correlation to tumor growth. RESULTS: There was no statistically significant difference between males and females with regards to age, tumor size and number of surgical procedures (p=0.279, p=813, p=139 respectively). There is a statistically significant correlation between the size of the tumor, the number of surgical procedures and hormonal deficiency (p=0.032, p=0.223 respectively). There was no statistically significant correlation between a positive immunohistochemistry for protein P53, protein C-erb-B2, Ki-67 and tumor size (r=0.182, p=0.396; r=-0.181, p=0.397; r=0.272, p=0.199, respectively). The tissue micro-array also did not demonstrate a correlation between positive immunohistochemistry for Ki-67 and C-erb-B2 and tumor size, but it showed a statistically significant correlation between a positive immunohistochemistry for p53 and tumor size (r=-0.696; p=001). CONCLUSION: The biological behavior of the clinically non-functioning adenoma is similar for both sexes. The larger the tumor the greater the number of surgical procedures needed. Hormonal deficiency also becomes more significant as the size of the tumor increases. This paper suggests that a positive immunohistochemistry for p53 is negatively correlated to tumor size, thus demonstrating that it has a predictor value. However, a positive immunohistochemistry for Ki-67 and protein C-erb-B2 does not seem to be a prognostic factor for clinically non-functioning pituitary adenomas, as is the case with other neoplasias.  相似文献   
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