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71.
Twelve normal-weight and 12 underweight women were compared to test whether fetal growth retardation in underweight gravidas is related to inadequate maternal hemodynamic adjustments. Plasma volume (+/- standard error) was 3227 +/- 103 mL in normal-weight and 2731 +/- 84 mL in underweight women (P less than .002). Cardiac output was 6340 +/- 167 mL/minute in controls and 5689 +/- 213 mL/minute in underweight women (P less than .03). Total peripheral vascular resistance was lower in controls than in underweight subjects (1025 +/- 31 versus 1198 +/- 58 dyne/second/cm5). Mean birth weight was 2837 +/- 125 g in underweight women and 3362 +/- 106 g in controls (P less than .005). Similarly, placental weight was reduced in the underweight group. All infants delivered by control mothers had a normal birth weight, whereas six infants from underweight gravidas were growth-retarded. In all cases combined, maternal plasma volume correlated significantly with both birth weight (r = 0.6, P less than .002) and placental weight (r = 0.56, P less than .01); total peripheral vascular resistance also correlated significantly and inversely with newborn weight and placental weight. Cardiac output correlated only with placental weight (r = 0.54, P less than .02). These results are consistent with the hypothesis that underweight mothers are at higher risk of fetal growth retardation because of a smaller plasma volume and lower cardiac output. 相似文献
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73.
BACKGROUND: Intraductal papillary mucinous tumors (IPMT) account for 5% of pancreatic neoplasms. Preoperative identification is important because of their frequent multifocal or diffuse involvement in pancreatic ducts, which makes extensive surgery necessary even in benign cases. To the authors' knowledge, the cytologic features of this entity in fine-needle aspiration biopsy (FNAB) specimens have seldom been described and are poorly standardized. METHODS: Eleven consecutive cases of surgically proven IPMT with previous endoscopic ultrasonography (EUS)-guided FNAB were collected for retrospective analysis. EUS-FNAB had been performed with on-site attendance of a cytopathologist in all cases. Macroscopic and microscopic appearance of mucin, cellular type and arrangement, presence of nuclear grooves, and degree of nuclear atypia were recorded. RESULTS: Final diagnosis was benign IPMT (B) in four cases, borderline IPMT (Bo) in two cases, malignant IPMT (M) in one case, and IPMT associated with invasive carcinoma (Ca) in four. Retrospective analysis found moderate to high levels of extracellular mucin in 10 of the 11 cases. The other case (one Ca) showed a small amount of thick mucin. In all cases, epithelial cells were identified, although cellularity was very low in four cases (three B and one Bo). Atypia was absent in two cases (two B) slight in two cases (two B), moderate in three cases (one Bo and two Ca), and severe in four cases (one Bo, one M, and two Ca). Mucinous epithelium was found in nine cases and nonmucinous epithelium in five cases (one Bo and four Ca). Papillary structures were observed in five cases (two Bo and three Ca), sheets in eight cases (four B, one Bo, one M, and two Ca), single atypical cells in five cases (one Bo and four Ca), irregular clusters in three cases (one Bo and two Ca), and nuclear grooves in two cases (one B and one Bo). CONCLUSIONS: The most common features of IPMT were extracellular mucin and sheets of mucinous epithelium. Papillae and nuclear grooves were not consistently found. Nonmucinous epithelium, severe atypia, single atypical cells, and irregular clusters indicated a high probability of malignant transformation. Even in the absence of atypia, a clinically significant diagnostic orientation can be established in most cases on the basis of the characteristic cytologic picture. 相似文献
74.
In any field in which decisions are subject to measurements, interchangeability between the methods used to obtain these measurements is essential. To consider methods as interchangeable, a certain degree of agreement is needed between the measurements they provide. The concordance correlation coefficient is an index that assesses the strength of agreement and it has been widely applied in situations in which measurements are made on a continuous scale. Recently the concordance correlation coefficient has been defined as a specific intraclass correlation coefficient estimated by the variance components of a Normal-Normal mixed linear model. Although this coefficient was defined for the continuous scale case, it may also be used with a discrete scale. In this case the data are often transformed and normalized, and the concordance correlation is applied. This study discusses the expression of the concordance correlation coefficient for discrete Poisson data by means of the Poisson-Normal generalized linear mixed model. The behaviour of the concordance correlation coefficient estimate is assessed by means of a simulation study, in which the estimates were compared using four models: three Normal-Normal mixed models with raw data, log-transformed data and square-root transformed data, and the Poisson-Normal generalized linear mixed model. An example is provided in which two different methods are used to measure CD34+ cells. 相似文献
75.
Hattermann K Müller MA Nitsche A Wendt S Donoso Mantke O Niedrig M 《Archives of virology》2005,150(5):1023-1031
Summary. In order to define and characterize target cells of SARS-coronavirus (SARS-CoV) we studied the susceptibility of 23 different permanent and primary eukaryotic cell lines to SARS-coronavirus. Beneath Vero E6 cells SARS- Coronavirus infection could also be demonstrated in two pig cell lines (POEK, PS) and one human cell line (Huh-7) using the indirect immunofluorescence assay and a newly established quantitative real-time PCR. In all susceptible cell lines mRNA of the Angiotensin-converting enzyme 2 (ACE2), the functional receptor for SARS-CoV infection, could be detected by RT-PCR. Our results show that there is a correlation between the abundance of ACE2 mRNA and SARS-CoV susceptibility. 相似文献
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77.
Several techniques have been advocated for knee arthrodesis, and there has been an increasing interest in modular intramedullary nails in the recent last years. We report a case of femoral and tibial fractures at each end of a modular nail in a solidly fused knee 8 months after an arthrodesis. 相似文献
78.
Fuxe K Ferré S Canals M Torvinen M Terasmaa A Marcellino D Goldberg SR Staines W Jacobsen KX Lluis C Woods AS Agnati LF Franco R 《Journal of molecular neuroscience : MN》2005,26(2-3):209-220
The existence of A2A-D2 heteromeric complexes is based on coimmunoprecipitation studies and on fluorescence resonance energy transfer and bioluminescence resonance energy transfer analyses. It has now become possible to show that A2A and D2 receptors also coimmunoprecipitate in striatal tissue, giving evidence for the existence of A2A-D2 heteromeric receptor complexes also in rat striatal tissue. The analysis gives evidence that these heteromers are constitutive, as they are observed in the absence of A2A and D2 agonists. The A2A-D2 heteromers could either be A2A-D2 heterodimers and/or higher-order A2A -D2 hetero-oligomers. In striatal neurons there are probably A2A-D2 heteromeric complexes, together with A2A-D2 homomeric complexes in the neuronal surface membrane. Their stoichiometry in various microdomains will have a major role in determining A2A and D2 signaling in the striatopallidal GABA neurons. Through the use of D2/D1 chimeras, evidence has been obtained that the fifth transmembrane (TM) domain and/or the I3 of the D2 receptor are part of the A2A-D2 receptor interface, where electrostatic epitope-epitope interactions involving the N-terminal part of I3 of the D2 receptor (arginine-rich epitope) play a major role, interacting with the carboxyl terminus of the A2A receptor. Computerized modeling of A2A-D2 heteromers are in line with these findings. It seems likely that A2A receptor-induced reduction of D2 receptor recognition, G protein coupling, and signaling, as well as the existence of A2A-D2 co-trafficking, are the consequence of the existence of an A2A-D2 receptor heteromer. The relevance of A2A-D2 heteromeric receptor complexes for Parkinson's disease and schizophrenia is emphasized as well as for the treatment of these diseases. Finally, recent evidence for the existence of antagonistic A2A-D3 heteromeric receptor complexes in cotransfected cell lines has been summarized. 相似文献
79.
80.
Alonso-Villaverde C Coll B Gómez F Parra S Camps J Joven J Masana L 《AIDS (London, England)》2005,19(3):341-342
Efavirenz treatment has been associated with increases in HDL-cholesterol concentrations, and the circulating levels of the drug have been related to the multidrug resistance gene 1 (MDR-1) C3435T polymorphism. The changes in the measured lipid parameters were evaluated in 59 HIV-infected patients initiating efavirenz-based treatment at baseline and at 12 months of follow-up. Efavirenz treatment increased HDL-cholesterol. The changes in concentrations appeared to be influenced by the MDR-1 gene polymorphism, in which CC > CT > TT. 相似文献