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61.
Cast syndrome     
The term cast syndrome is used to denote duodenal obstruction occurring after application of a corrective plaster cast to patients with scoliosis. We report a classical case in a 14-year-old female who required surgical intervention after conservative treatment failed. Six months later the patient had no further gastrointestinal symptoms. Clinical, radiological, and pathological details as well as the surgical treatment are described and discussed. Offprint requests to: M. E. Martín Hortigüela  相似文献   
62.
Radioimmunoassay techniques were used to detect antibodies to the acetylcholine receptor (AAChR) in 164 patients with adult-onset myasthenia gravis. AAChR levels above 0.6 nM/l were considered pathological and were found in 67% of the patients with an average value of 58.99 +/- 125.02 nM/l (0.6-900.0). Correlation, with clinical functional status, the histopathological thymus alterations and the different therapeutics used did not disclose any statistically significant differences.  相似文献   
63.
Abstract –  The main objective of this study was to assess the epidemiology of traumatic dental injuries (TDI) to the primary teeth of preschool children and second, to investigate whether TDI were related to anterior open bite and, third, whether TDI are related to socio-economic circumstances in an urban Brazilian population. A clinical examination was performed during the National Day of Children's Vaccination. TDI were classified according to the modified classification proposed by Ellis. In addition to those criteria the presence of tooth discoloration was recorded. An interview was carried out with mothers or guardians. The data collected included mother's level of education and living conditions. The prevalence of TDI was 9.4%. The maxillary central incisors were the most affected teeth. Most children with a TDI experienced traumatic injuries to one tooth (6.3%), while 2.8% had two and 0.4% had three traumatized teeth. The most common crown fracture was in enamel only (68.8%), followed by crown fracture of enamel and dentin (13.8%). Missing teeth following trauma occurred in 10.9% of those with TDI. The prevalence of tooth discoloration was 5.1%. Children with anterior open bite had twice the level the level of TDI compared to those with normal occlusions ( P  = 0.001). Socio-economic factors were not statistically significantly associated with the occurrence of TDI. The prevalence of dental injuries in Brazilian preschool children was low. Children with anterior open bite experienced more dental injuries. Neither of the indicators of socio-economic status was related to the prevalence of TDI.  相似文献   
64.
Steady-state distribution spaces of 2-[14C]deoxyglucose ([14C]DG), glucose, and 3-O-[14C]methylglucose at various concentrations of glucose in brain and plasma ranging from hypoglycemic to hyperglycemic levels have been determined by direct chemical analyses in the brains of conscious rats. The hexose concentrations were measured chemically in freeze-blown brain extracted with ethanol to avoid the degradation of acid-labile products of [14C]DG back to free [14C]DG that has been found to occur with the more commonly used perchloric acid extraction of brain. Corrections were also made for nonphosphorylatable, labeled products of [14C]DG found in the nonacidic fractions of the brain extracts, which were previously included with the assayed [14C]DG, and for the contribution of the hexose contents in the blood in the brain, which was found to be particularly critical for the determination of the glucose distribution space, especially in hypoglycemic states. From the measured contents of the hexoses in brain and plasma, the relationships of the tissue concentrations and distribution spaces of each of the hexoses and of the lambda (i.e., ratio of tissue distribution space of DG to that of glucose) of the DG method to the tissue glucose concentration were derived. The lambda was then quantitatively related to the measured equilibrium ratio for [14C]methylglucose over the full range of brain and plasma glucose levels. By combining these new data with the values for the lumped constant, the factor that converts the rate of DG phosphorylation to glucose phosphorylation, previously determined in rats over the same range of plasma glucose levels, the phosphorylation coefficient was calculated and the lumped constant graphed as a function of the measured distribution space in brain for [14C]methylglucose.  相似文献   
65.
Four communities from Guahibo of Venezuela were analyzed for the genetic variants of nine erythrocyte enzymes and five serum proteins. Of the 14 loci determined, four were monomorphic. Significant frequency differentiation among communities, was present for ESD and TF markers. In general, Guahibo allele frequencies are in the variation ranges described for South American groups. The analysis indicates a relatively higher affinity of Guahibos with other Venezuelan groups within an irregular pattern of genetic distances that are likely related to the complex demographic history of the South American groups. Genetic diversity estimates reveal a moderate degree of genetic structure between the four Guahibo communities. This intra‐tribal variability in Guahibo appears to be lower than in Venezuelan Piaroa but higher than in other Amerindians and could be attributed to a combined effect of low population size and relative isolation of communities. At a continental level, the distribution of genetic diversity is consistent with preferential population movements along the eastern and western coastal areas. Am. J. Hum. Biol. 14:21–28, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
66.
The steady-state distribution volumes of glucose, 3-O-methylglucose, and 2-deoxyglucose (2DG) are known to change as the concentration of glucose in plasma ranges from hypo- to hyperglycemic values. Model estimates of the three distribution volumes were compared with distribution volume values experimentally measured in the brains of conscious rats as the concentration of glucose in plasma was varied from 2 to 28 mM. The dependence on plasma glucose concentration of the 2DG lumped constant, the factor that relates the phosphorylation rate of 2DG to the net rate of glucose utilization at unit specific radioactivity in the plasma, had been determined previously in separate series of experiments. The model was extended to incorporate this dependence of the lumped constant. In the model both the transport and the phosphorylation barriers were assumed to be single and saturable. The values of their respective half-saturation concentrations and the ratio of the two maximum velocities for glucose were assumed to be invariant over the entire range of plasma glucose concentration. Good agreement between measured and estimated values for the distribution volumes and the lumped constant was attained over the full range of plasma glucose concentration. The model estimates reflected the progressive transport limitation of the brain glucose content as plasma glucose levels were reduced to hypoglycemic values. The results also indicated that these changes should be evident in the time course of 2DG in brain following administration by bolus or continuous infusion, and thus that indexes of local lumped constant change could be derived from the time course data.  相似文献   
67.
We performed multidirectional chromosome painting in a comparative cytogenetic study of the three howler monkey species Alouatta fusca, A. caraya and A. seniculus macconnelli (Atelinae, Platyrrhini) in order to reconstruct phylogenetic relationships within this genus. Comparative genome maps between these species were established by multicolor fluorescence in-situ hybridization (FISH) employing human, Saguinus oedipus and Lagothrix lagothricha chromosome-specific probes. The three species included in this study and previously analyzed howler monkey species were subjected to a phylogenetic analysis on the basis of a data matrix comprised of 98 discrete molecular cytogenetic characters. The results revealed that howler monkeys represent the genus with the most extensive karyotype diversity within Platyrrhini so far analyzed with high levels of intraspecific chromosomal variability. Two different multiple sex chromosome systems were identified. The phylogenetic analysis indicated that Alouatta is a monophyletic clade which can be derived from a proposed ancestral Atelinae karyotype of 2n=62 chromosomes by a chromosome fusion, a fission, a Y-autosomal translocation and a pericentric inversion. Following these suggestions, the genus Alouatta can be divided into two distinct species groups: the first includes A. caraya and A. belzebul, the second A. s. macconnelli, A. sara, A. s. arctoidea and A. fusca.  相似文献   
68.
OBJECTIVE: Clinical, radiographic, and microbiologic changes in deep caries lesions were assessed after incomplete carious dentin removal and tooth sealing. METHOD AND MATERIALS: Thirty-two teeth with deep caries lesions were studied. Treatment consisted of incomplete excavation of the demineralized dentin, application of calcium hydroxide, and sealing for a 6- to 7-month period. The color and consistency of the dentin were clinically assessed. Differences in radiographic density were assessed by digital image subtraction. Microbiologic samples were obtained from the demineralized dentin before the temporary sealing and after the experimental period. The samples were cultivated on blood agar under aerobic and anaerobic conditions, in Mitis Salivarius agar, and Rogosa selective Lactobacillus agar. RESULTS: Two cases were lost during the study; one presented pulpal necrosis. In the other case, there was pulpal exposure during removal of provisional sealing. In all teeth, the initial demineralized dentin was soft and wet; one lesion was yellow, 21 were light brown, and eight were dark brown. After treatment, the dentin was dry, and 80.00% of specimens were hard, 16.67% were leathery, and 3.33% remained soft. The dentin was light brown in five teeth and dark brown in 25. There was a statistically significant mean difference in radiographic density (pixel intensity), 88.77 +/- 7.02 in the control areas and 94.66 +/- 6.75 in the test areas. The counts of anaerobic and aerobic bacteria, lactobacilli, and Streptococci mutans had decreased significantly by the end of treatment. CONCLUSION: Incomplete removal of carious dentin and subsequent tooth sealing resulted in the arrest of the lesions, suggesting that complete dentinal caries lesion removal is not essential to the control of caries lesions.  相似文献   
69.
Grip strength is one of the traditional outcome measures commonly used in rheumatoid arthritis trials. This study evaluated the degree of morning variation and the effect of elbow flexion in the assessment of grip strength in patients with rheumatoid arthritis. Grip strength was measured in 37 patients (1987 American Rheumatism Association criteria) at 8, 10, and 12 AM with a sphygmomanometer cuff folded on itself, taped permanently, and inflated to 20 mm Hg, with the elbow flexed at 90 degrees. At 10 AM grip strength was also measured with the elbow flexed at 30 and 130 degrees. Mean values for grip strength at 8, 10, and 12 AM were, respectively, 69, 79, and 83 mm Hg. Mean grip strength values with the elbow flexed at 30, 90, and 130 degrees were, respectively, 78, 79, and 75 mm Hg. There was a statistically significant correlation between grip strength and morning stiffness, grip strength and hand function, and grip strength and number of active joints. In rheumatoid arthritis trials, grip strength should be assessed at the same time of the day. Elbow flexion does not play a role in grip strength measurement.  相似文献   
70.
Summary The antiproteinuric effect of the antiplatelet agent dipyridamole has been assessed after inhibiton of thromboxane B2 (TxB2) synthesis in 8 patients with confirmed membranous glomerulonephritis. There were three study periods, each of 30 days, and 45 days apart, namely a washout period, treatment with dipyridamole 300 mg/d, and dipyridamole 225 mg/d plus aspirin 150 mg/d. On Days 1 and 30 of each study period serum and urine creatinine, 24-h excretion of protein, creatinine clearance, platelet aggregometry on whole blood and serum TxB2 were measured. Treatment with dipyridamole alone or with aspirin produced significant inhibition of platelet aggregation and a fall in 24-h protein excretion; the latter amounted to 54% with dipyridamole alone and 56 % with dipyridamole plus aspirin (NS). Dipyridamole plus aspirin caused an 82 % reduction in serum TxB2.  相似文献   
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