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51.
MM Anceschi JJ Piazze Garnica V Unfer MR Di Benedetto EV Cosmi 《Canadian Metallurgical Quarterly》1996,24(4):355-362
Our aim was to determine the diagnostic accuracy and reliability of four tests for the assessment of fetal lung maturity (FLM): shake test, optical density at 650 nm (OD650), lecithin to sphingomyelin ratio (L/S) by planimetry and stechiometry, and presence of phosphatydylglycerol. Amniotic fluid was obtained from 74 patients at various gestational ages. The shake test and the OD650 were performed according to published methods L/S was determined by TLC (thin-layer chromatography) and the ratio assessed by planimetry and stechiometrically by measurement of organic phosphorus from the chromatographic spots. PG was assessed similarly by TLC. When correlated with gestational age at amniocentesis, all tests correlated positively: shake test (r = 0.46, p < 0.005); OD650 (r = 0.31, p < 0.005); planimetric L/S (r = 0.77, p < 0.005); stechiometric L/S (r = 0.52, p < 0.005) and PG (r = 0.54, p < 0.005). The diagnostic accuracy of each test was as follows: the shake test and the OD650 had a sensitivity of 50%, while the steciometric L/S had a sensitivity of 75%, the planimetric L/S and the presence of PG were 100%. All four tests demonstrated a specificity greater than 64%, the highest for the PG presence being (83%) and the shake test (86%). Predictive negative values for lung maturity were > 93% for all tests, with the highest for the planimetric L/S and presence of PG being (100%). The study confirms that the determination of L/S ratio is still superior to other tests in terms of overall diagnostic accuracy. In addition, it was found that presence of PG was highly associated with the absence of respiratory complications in the newborn. 相似文献
52.
EV Chandrasekaran RK Jain RD Larsen K Wlasichuk KL Matta 《Canadian Metallurgical Quarterly》1996,35(27):8914-8924
The assembly of complex structures bearing the H determinant was examined by characterizing the specificities of a cloned blood group H gene-specified alpha 1,2-L-fucosyltransferase (FT) toward a variety of sulfated, sialylated, or fucosylated Gal beta 1,3/4GlcNAc beta- or Gal beta 1,3GalNAc alpha-based acceptor structures. (a) As compared to the basic type 2, Gal beta 1,4GlcNAc beta-(K(m) = 1.67 mM), the basic type 1 was 137% active (K(m) = 0.83 mM). (b) On C-6 sulfation of Gal, type 1 became 142.1% active and type 2 became 223.0% active (K(m) = 0.45 mM). (c) On C-6 sulfation of GlcNAc, type 2 showed 33.7% activity. (d) On C-3 or C-4 fucosylation of GlcNAc, both types 1 and 2 lost activity. (e) Type 1 showed 70.8% and 5.8% activity, respectively, on C-6 and C-4 O-methylation of GlcNAc. (f) Type 1 retained 18.8% activity on alpha 2,6-sialylation of GlcNAc. (g) Terminal type 1 or 2 of extended chain had lower activity. (h) With Gal in place of GlcNAc in type 1, the activity became 43.2%. (i) Compounds with terminal alpha 1,3-linked Gal were inactive. (j) Gal beta 1,3GalNAc alpha- (the T-hapten) was approximately 0.4-fold as active as Gal beta 1,4GlcNAc beta-. (k) C-6 sulfation of Gal on the T-hapten did not affect the acceptor activity. (l) C-6 sulfation of GalNAc decreased the activity to 70%, whereas on C-6 sulfation of both Gal and GalNAc the T-hapten lost the acceptor ability. (m) C-6 sialylation of GalNAc also led to inactivity. (n) beta 1,6 branching from GalNAc of the T-hapten by a GlcNAc residue or by units such as Gal beta 1, 4GlcNAc-, Gal beta 1,4(Fuc alpha 1,3)GlcNAc-, or 3-sulfoGal beta 1,4GlcNAc- resulted in 111.9%, 282.8%, 48.3%, and 75.3% activities, respectively. (o) The enhancement of enzyme affinity by a sulfo group on C-6 of Gal was demonstrated by an increase (approximately 5-fold) in the K(m) for Gal beta 1,4GlcNAc beta 1,6(Gal beta 1,3)GalNAc alpha-O-Bn in presence of 6-sulfoGal beta 1,- 4GlcNAc beta-O-Me (3.0 mM). (p) Among the two sites in Gal beta 1, 4GlcNAc beta 1,6(Gal beta 1,3) GalNAc alpha-O-Bn, the enzyme had a higher affinity ( > 3-fold) for the Gal linked to GlcNAc. (q) With respect to Gal beta 1,- 3GlcNAc beta-O-Bn (3.0 mM), fetuin triantennary asialo glycopeptide (2.4 mM), bovine IgG diantennary glycopeptide (2.8 mM), asialo Cowper's gland mucin (0.06 mM), and the acrylamide copolymers (0.125 mM each) containing Gal beta 1,3GlcNAc beta-, Gal beta 1,3(6-sulfo)GlcNAc beta-, Gal beta 1,3GalNAc alpha-, Gal beta 1,3Gal beta-, or Gal alpha 1,3Gal beta- units were 153.6%, 43.0%, 6.2%, 52.5%, 94.9%, 14.7%, 23.6%, and 15.6% active, respectively. (r) Fucosylation by alpha 1,2-L-FT of the galactosyl residue which occurs on the antennary structure of the bovine IgG glycopeptide was adversely affected by the presence of an alpha 1,6-L-fucosyl residue located on the distant glucosaminyl residue that is directly attached to the asparagine of the protein backbone. This became evident from the 4-fold activity of alpha 1,2-L-FT toward bovine IgG glycopeptide after approximately 5% removal of alpha 1,6-linked Fuo. 相似文献
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54.
We report a 2.5-year-old child who presented with an acute abdomen caused by the perforation of a sewing pin through her appendix that had started to penetrate the wall of the bladder. 相似文献
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57.
ID Grozdova NA Alexandrova EV Sveshnikova NS Melik-Nubarov PG Sveshnikov ES Severin 《Canadian Metallurgical Quarterly》1996,40(6):1159-1166
The regulatory subunit type II (RII) of cAMP-dependent protein kinase purified from human brain was represented by two proteins with apparent molecular masses of 51-52 kD and 54 kD. Dephosphorylation of human RII containing 3 mol phosphate/mol protein did not change the electrophoretic pattern. One-dimensional peptide mapping of 51-52 kD and 54 kD proteins after digestion with St. aureus V8 protease evidenced to their being distinct proteins. The data obtained permit to assume that human RII of neural type is represented by two isoforms. 相似文献
58.
The neurophysiological basis of attention control was studied in infants at the second half-year of life, i.e. in the period when the capability for voluntary control over behavior fundamentally improves. EEG was recorded in 60 infants aed 8-11 months in three experimental conditions: 1) attention to an object in the visual field (externally controlled attention, or the baseline state), 2) anticipation of a person in the peek-a-boo game (internally controlled attention), 3) attention to the reappeared person in the peek-a-boo game (control condition). The spectral analysis of the EEG data revealed a sharp increase in the EEG theta (3.6-6.0 Hz) during internally controlled attention as compared to the baseline and control conditions. The theta1 (3.6-4.8 Hz) increase was maximal in the frontal derivations. The reactivity of the frontal theta1 during internally controlled attention discriminated infants with different abilities to maintain this type of attention. The reactivity of the theta2 (5.2-6.0 Hz) was maximal in the right temporal derivation (T6) and did not depend on stability of the anticipatory attention. The findings point to different functional significance of the theta1 and theta2 rhythms in infants. It is suggested that synchronization of the frontal theta1 rhythm in infants reflects the activity of the anterior attention system which realizes the executive attention control. The ability to maintain anticipatory attention increased with age, whereas the frontal theta1 synchronization decreased and totally disappeared at the age of 11 months. At the age of 8 months there was a positive correlation between the frontal theta1 synchronization and behavioral index of stability of the internally controlled attention. On the contrary, this correlation was negative at the age of 9 and 10 months. It is suggested that the age-dependent dynamics of the relationship between the frontal theta1 reactivity and attention reflects a leap in maturation of the anterior attention system resulting in its more economic and efficient functioning. 相似文献
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335 patients with obliterative diseases of arteries of the low extremities were examined. Results of motor rehabilitation depend on the severity of post-amputation defect of the extremity and functional condition of the stump. The lower is the level of the amputation the higher is the effectiveness of the rehabilitational measures. Ischemia of femoral stump springs up rarely but its course is mare severe than ischemia of the stump of the shin, which is confirmed by the data of clinical examination, investigation of biochemical parameters of the blood and mortality rate. For prophylaxis of ischemia of the stump it is suggested simultaneously with the amputation of the extremity to perform reconstructive procedures on the arteries, aimed at restoration of blood flow through the profound femoral artery. This policy provides the possibility to form a long functional stump of the extremity and to improve results of motor rehabilitation. 相似文献