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151.
Romero GA Flores M RM Noronha EF Macêdo Vde O 《Memórias do Instituto Oswaldo Cruz》2003,98(1):145-149
We analyzed data from historical controls treated with meglumine antimoniate to compare the frequency of adverse events observed in patients with cutaneous leishmaniasis treated with the same dose of meglumine antimoniate contaminated with heavy metals in an endemic area of the State of Bahia, Brazil. Group A patients were treated in 2000 with the drug produced by Eurofarma Laborat rios Ltda., S o Paulo, Brazil (lot A) and group B patients were treated in 1996 with the reference drug produced by Rhodia Farma Ltda., S o Paulo, Brazil (lot B). We observed an unusual higher frequency of skin reactions in group A patients. However, all type of adverse events observed in group A were also observed in group B. The physico-chemical analysis of these lots revealed that lot A had lower pH and higher concentration of total and trivalent antimony, lead, cadmium, and arsenic. Our findings suggest that the skin reactions could be attributed to heavy metal contamination of lot A. 相似文献
152.
Patterns of parasite abundance and prevalence are thought to be influenced by several host characteristics such as size, sex, developmental stage, and seasonality. We examined two obligatory ectoparasites of the bat Noctilio leporinus (L.) (Chiroptera, Noctilionidae) to test whether prevalence and abundance of Noctiliostrebla aitkeni Wenzel and Paradyschiria fusca Speiser (Diptera, Streblidae) are influenced by the host characteristics. During this survey, 2110 flies were collected. The total abundance was 1150 N. aitkeni and 950 P. fusca. The prevalence of both species was shown to be superior to 75% and neither host size, sex, reproductive stage nor season influenced significantly the variation of the observed values. N. aitkeni were more abundant than P. fusca in all seasons except winter. Both flies showed a significant seasonal variation in terms of abundance but host biological characteristics (host size, sex, and reproductive stage) did not play a significant role as structuring factors of the batflies component community. 相似文献
153.
Bernal C Velásquez C García G Uribe G Palacio CM 《Biomédica : revista del Instituto Nacional de Salud》2003,23(1):47-59
A clinical trial was conducted to compare the efficacy of a low-osmolarity solution (245 mOsm/L), and a standard oral rehydration solution (ORS) recommended by WHO for children dehydrated by diarrhea. Group 1 (69 children) received WHO/ORS (311 mOsml/L) and group 2 (71 children) received a low-osmolarity solution (245 mOsm/L). Rehydration was successful in 88.4% in group 1 and 92.9% in group 2 (p = 0.35). Rehydration was completed in 5.2 h (SD +/- 1.8) in group 1 and 5.5 (SD +/- 1.7) in group 2 (p = 0.31). Stool output was 6.3 g/kg/h (SD +/- 5.0) in group 1 and 5.6 g/kg/h (SD +/- 5.1) in group 2 (p = 0.94). Sodium at rehydration-completion was 139.3 mEq/L (SD +/- 7.1) in group 1 and 136.7 mEq/L (SD +/- 4.3) in group 2 (p = 0.014). Group 1 was under observation for 21 hours (SD +/- 5.7) and group 2, for 22 hours (SD +/- 5.6). Stool output in group 1 was 5.2 g/kg/h (SD 4.1) and 4.2 gr./kg/h (SD +/- 4.1) in group 2 (p = 0.16). In group 1, 23.1% required intravenous solutions and 9.8% in group 2 (p = 0.03). In treating dehydrated children, the low-osmolarity solution diminished the need for intravenous solutions, corrected most plasmatic sodium disorders, and produced no-risk of developing hyponatremia. 相似文献
154.
Cembrano GL Rodríguez-Vázquez A Espejo Meana S Domínguez-Castro R 《International journal of neural systems》2003,13(6):427-434
This paper presents a new generation 128x128 Focal-Plane Analog Programmable Array Processor -FPAPAP, from a system level perspective. It has been manufactured in a 0.35 microm standard digital 1P-5M CMOS technology. It has been designed to achieve the high-speed and moderate-accuracy -8b- requirements of most real time -early-vision applications. External data interchange and control are completely digital. The chip contains close to four million transistors, 90% of them working in analog mode. It achieves peak computing values of 0.33TeraOPS while keeping power consumption at reasonable limits -82.5GOPS/W. Preliminary experimental results are also provided in the paper. 相似文献
155.
García H Salguero GA Moreno J Arteaga C Giraldo A 《Biomédica : revista del Instituto Nacional de Salud》2003,23(2):161-172
At the Instituto Materno Infantil (IMI) in Bogotá (Colombia), 5,686 births (5,597 live births and 89 stillbirths) were analyzed during two periods: from October, 1997, to April, 1998, and from July to November, 2000 (12 months). Congenital anomalies were detected in 4.4% of live newborn babies and in 7.8% of stillbirths. Major anomalies corresponded to 69% and mild anomalies to 31% (3% and 1.4% of all live births, respectively). The newborn babies with major anomalies, in comparison to the normal controls, had higher mortality at hospital discharge (p = 0.0001), lower average birth weight (p = 0.003), and family history of congenital anomalies (p = 0.0001). The only significant association for mild anomalies was with family history of congenital anomalies (p = 0.0001). The frequency of congenital anomalies was similar to that in other studies, although certain kinds of anomalies showed noticeable frequency differences. This may be a consequence of differences in record keeping or in detection methods. 相似文献
156.
Disruption of the FATB gene in Arabidopsis demonstrates an essential role of saturated fatty acids in plant growth 总被引:3,自引:0,他引:3
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Acyl-acyl carrier protein thioesterases determine the amount and type of fatty acids that are exported from the plastids. To better understand the role of the FATB class of acyl-acyl carrier protein thioesterases, we identified an Arabidopsis mutant with a T-DNA insertion in the FATB gene. Palmitate (16:0) content of glycerolipids of the mutant was reduced by 42% in leaves, by 56% in flowers, by 48% in roots, and by 56% in seeds. In addition, stearate (18:0) was reduced by 50% in leaves and by 30% in seeds. The growth rate was reduced in the mutant, resulting in 50% less fresh weight at 4 weeks compared with wild-type plants. Furthermore, mutant plants produced seeds with low viability and altered morphology. Analysis of individual glycerolipids revealed that the fatty acid composition of prokaryotic plastid lipids was largely unaltered, whereas the impact on eukaryotic lipids varied but was particularly severe for phosphatidylcholine, with a >4-fold reduction of 16:0 and a 10-fold reduction of 18:0 levels. The total wax load of fatb-ko plants was reduced by 20% in leaves and by 50% in stems, implicating FATB in the supply of saturated fatty acids for wax biosynthesis. Analysis of C(18) sphingoid bases derived from 16:0 indicated that, despite a 50% reduction in exported 16:0, the mutant cells maintained wild-type levels of sphingoid bases, presumably at the expense of other cell components. The growth retardation caused by the fatb mutation was enhanced in a fatb-ko act1 double mutant in which saturated fatty acid content was reduced further. Together, these results demonstrate the in vivo role of FATB as a major determinant of saturated fatty acid synthesis and the essential role of saturates for the biosynthesis and/or regulation of cellular components critical for plant growth and seed development. 相似文献
157.
Gustavo?MalingerEmail author Dorit?Lev Tally?Lerman-Sagie 《Reproductive biology and endocrinology : RB&E》2003,1(1):110
A considerable number of central nervous system pathologies remain undiagnosed during the first two trimesters of pregnancy.
This group of disorders includes anomalies of brain proliferation, migration and cortical organization. Due to the fact that
a detailed ultrasound examination of the fetal brain is usually not performed during the third trimester the diagnosis of
these disorders is usually only made in families with a previously affected child or in many cases be mere chance. In this
article we review the feasibility of prenatal diagnosis of disorders of brain proliferation: microcephaly, macrocephaly, hemimegalencephaly
and neoplastic and non-neoplastic abnormal cell types. We discuss the differential diagnosis and offer a stepwise approach
to the diagnosis of the more common disorders. 相似文献
158.
The aim of this study was to test the hypothesis that polyvinylpyrrolidone (PVP) would increase the critical micelle concentration
(CMC) of nonoxynol-9 (N-9), providing a reduction in its irritation potential, while maintaining essential spermicidal activity.
Solid coprecipitates of N-9 with PVP were manufactured with the use of a modified lyophilization process. The irritation potential
of N-9 was estimated by an in vitro assay, monitoring the extent of hemolysis of red blood cells. CMCs of N-9 were measured
in the presence of various concentrations of PVP. A modified Sander-Cramer assay was implemented to measure the spermicidal
activity of N-9 and the N-9/PVP coprecipitates. With the use of the lyophilization process and more suitable solvents, solid
coprecipitates of N-9/PVP were manufactured with no residual organic solvents. The irritation potential of N-9 was reduced
when in the presence of PVP-50% hemolysis values increased from 0.054mM to more than 0.2mM. N-9 CMC values increased in the
presence of PVP from 0.085mM (0% PVP) to 0.110mM (3.5% PVP) and 0.166mM (10% PVP). However, spermicidal activities ranged
from 0.213mM to 0.238mM, N-9 remaining steady regardless of the amount of PVP. By use of N-9/PVP coprecipitates, the self-association
properties and irritation potentials of N-9 were altered. This result suggests a process to produce a spermicidal product
that reduces the detrimental implications to the vaginal epithelium while maintaining the essential spermicidal activity. 相似文献
159.
Vonasek E Mateu L Luzzati V Marquez G Vargas R Céspedes G Cotúa M Borges J 《European biophysics journal : EBJ》2001,30(1):11-16
A sural nerve dissected from a recently dead patient displayed an unusual X-ray diffraction pattern, suggesting that in situ and at the time of the patient's death the myelin sheaths were in a swollen state. Diffraction patterns of the swollen type were also recorded from: (1) a sural nerve from the corpse of a neurologically healthy person after soaking the nerve with Ringer solution at pH 5.5; (2) sciatic nerves dissected from rat cadavers at increasing time after death. In all the cases the swollen patterns reversed to the native type upon superfusion with Ringer solution at pH 7.3. The postmortem effect is to decrease the pH of the fluids surrounding the nerves in the cadavers. Our experiments show that the early postmortem processes have the effect of acidifying PNS nerves and that as a consequence of acidification the myelin sheaths swell. 相似文献
160.
The molecular analysis of a genomic region of B. megaterium revealed the presence of a gene coding for the enzyme phosphotransbutyrylase (Ptb). The enzyme activity was measured throughout
the different phases of growth in B. megaterium, and its activity was found to be maximal in the late exponential growth phase. The branched amino acids isoleucine and valine
activated Ptb expression. PtbBm was capable of using butyryl-CoA and 2-methyl-propionyl CoA as substrates. ActBm, a sigma54 regulator from B. megaterium whose gene is situated upstream from the ptb gene, activated its expression.
Received: 14 September 2000 / Accepted: 13 October 2000 相似文献