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91.
B Barlow E Tabor WA Blanc TV Santulli RC Harris 《Canadian Metallurgical Quarterly》1976,89(6):934-940
Nineteen cases of choledochal cyst are reviewed. Two distinct groups of patients were identified. Patients under one year of age, initially diagnosed as having biliary atresia, had a higher mortality rate, a higher incidence of severe cirrhosis with portal hypertension, and associated atresia or stenosis in the biliary tree. The second group, presenting between 3 and 20 years of age with more classic symptoms, had mild cirrhosis without portal hypertension and had associated choledocholithiasis and pancreatitis. It is suggested that the younger patients had a congenital form of cystic bile duct dilatation and that the older patients had an acquired form, perhaps related to a common channel with reflux of pancreatic juice into the common bile duct. Postoperative follow-up supports the current view that choledochocyst-jejunostomy with choleystectomy has a lower rate of long-term complications than does choledochocyst-duodenostomy. 相似文献
92.
SV Skurkovich AS Skorikova NA Dubrovina TV Riabova EI Eremkina VN Golodnenkova EG Klinova AJ Olshanski NF Shurlapova 《Canadian Metallurgical Quarterly》1977,39(5):344-350
A research study and discussion of antiinterferon immunoglobulin in the treatment of rheumatoid arthritis and systemic lupus erythematosus, and its possible value in the treatment of allergic diseases, autoimmune diseases and other diseases where it is presumed there may be an autoimmune genesis. 相似文献
93.
94.
95.
GM Howard TV Nguyen M Harris PJ Kelly JA Eisman 《Canadian Metallurgical Quarterly》1998,13(8):1318-1327
This study was designed to assess the relative contributions of genetic and environmental factors to the variation and covariation of quantitative ultrasound (QUS) measurements and their relationships to bone mineral density (BMD). Forty-nine monozygotic (MZ) and 44 dizygotic (DZ) female twins between 20 and 83 years of age (53 +/- 13 years, mean +/- SD) were studied. Digital (phalangeal) QUS (speed of sound [SOS]) and calcaneal QUS (broadband ultrasound attenuation [BUA] and velocity of sound [VOS]) were measured using a DBM Sonic 1200 ultrasound densitometer and a CUBA ultrasound densitometer, respectively. Femoral neck (FN), lumbar spine (LS), and total body (TB) BMD were measured using dual-energy X-ray absorptiometry. Familial resemblance and hence heritability (proportion of variance of a trait attributable to genetic factors) were assessed by analysis of variance, univariate, and multivariate model-fitting genetic analyses. In both QUS and BMD parameters, MZ twins were more alike than DZ pairs. Estimates of heritability for age- and weight-adjusted BUA, VOS, and SOS were 0.74, 0.55, and 0.82, respectively. Corresponding indices of heritability for LS, FN, and TB BMD were 0.79, 0.77, and 0.82, respectively. In cross-sectional analysis, both BUA and SOS, but not VOS, were independently associated with BMD measurements. However, analysis based on intrapair differences suggested that only BUA was related to BMD. Bivariate genetic analysis indicated that the genetic correlations between BUA and BMD ranged between 0.43 and 0.51 (p < 0.001), whereas the environmental correlations ranged between 0.20 and 0.28 (p < 0.01). While the genetic correlations within QUS and BMD measurements were significant, factor analysis indicates that common genes affect BMD at different sites. Also, individual QUS measurements appear to be influenced by some common sets of genes rather than by environmental factors. Significant environmental correlations were only found for BMD measurements and ranged between 0.50 and 0.65 (p < 0.001). These data suggest that QUS and BMD measurements are highly heritable traits. While it appears that there is a common set of genes influencing both QUS and BMD measurements, specific genes yet to be identified appear to have greater effects than that of shared genes in each trait. 相似文献
96.
NI Perrone-Bizzozero TV Isaacson GM Keidan C Eriqat KF Meiri DD Savage AM Allan 《Canadian Metallurgical Quarterly》1998,71(5):2104-2111
Consumption of moderate quantities of ethanol during pregnancy produces deficits in long-term potentiation in the hippocampal formation of adult offspring. Protein kinase C (PKC)-mediated phosphorylation of the presynaptic protein GAP-43 is critical for the induction of long-term potentiation. We tested the hypothesis that this system is affected in fetal alcohol-exposed (FAE) rats by measuring GAP-43 phosphorylation and PKC activity in the hippocampus of adult offspring of rat dams that had consumed one of three diets throughout gestation: (a) a 5% ethanol liquid diet, which produced a maternal blood ethanol concentration of 83 mg/dl (FAE); (b) an isocalorically equivalent 0% ethanol diet (pair-fed); or (c) lab chow ad libitum. Western blot analysis using specific antibodies to PKC-phosphorylated GAP-43 revealed that FAE rats had an approximately 50% reduction in the proportion of phosphorylated GAP-43. Similarly, we found that PKC-mediated incorporation of 32P into GAP-43 was reduced by 85% in hippocampal slices from FAE rats compared with both control groups. FAE animals also showed a 50% reduction in total hippocampal PKC activity, whereas the levels of six major PKC isozymes did not change in any of the diet groups. These results suggest that GAP-43 phosphorylation deficits in rats prenatally exposed to moderate levels of ethanol are not due to alterations in the expression of either the enzyme or substrate protein, but rather to a defect in kinase activation. 相似文献
97.
D Gautrin C Infante-Rivard TV Dao M Magnan-Larose D Desjardins JL Malo 《Canadian Metallurgical Quarterly》1997,155(6):1841-1847
Atopy, specific IgE sensitization, and bronchial hyperresponsiveness (BHR) were examined in a cohort of 769 apprentices starting career programs in animal health or veterinary medicine (Group 1), pastry making (Group 2), and dental hygiene (Group 3). The hypothesis were that: (1) a proportion of subjects can be "sensitized" although no significant specific occupational exposure has occurred; and (2) there is a relationship between baseline specific sensitization to work-related antigens and host characteristics. Skin tests were administered using 11 common inhalants and specific allergens, including six laboratory animal extracts, three cereal antigens, alpha-amylase, and latex. Methacholine challenge tests were performed. The prevalence of atopy was 54.4% in Group 1, 58.1% in Group 2, and 52.5% in Group 3. Skin reactivity to work-specific proteins was as follows: laboratory animal proteins, 13.8% in Group 1, 14.0% in Group 2, and 15.6% in Group 3. No subject was sensitized to alpha-amylase, whereas 1.2% in Group 1, 5% in Group 2, and 4.1% in Group 3 were sensitized to flour. Five subjects reacted to latex. BHR (PC20 < or = 8 mg/ml) was present in 17.6%, 21.2%, and 14.8% of subjects in Groups 1, 2, and 3, respectively. Specific sensitization was associated with positive skin reactions to common allergens, work-related symptoms, and BHR. These results suggest that students starting career programs with exposure to high-molecular-weight allergens have a low but substantial frequency of specific sensitization to work-related allergens that is related to atopy and BHR. 相似文献
98.
Individual somatotype parameters and peculiarities of constitution in 7-12 years boys were evaluated in the present investigation. The age range studied was shown to be divided on 3 stages. Regular growth processes with the prevalence of "infantal" proportions occur at the age of 7-9. Signs of definite constitutional type are expressed yet insufficiently. The age of 10-11 is transitional which shows in delay of muscle growth. At the age of 11-12 prepubescent sets in, during which features of constitution types and appropriate somatotype parameters are distinctly manifested. 相似文献
99.
MA Gorbunov LI Pavlova IA Titov TA Bektimirov VP Selezneva OIu Shitikova TV Mamontova IN Indikova 《Canadian Metallurgical Quarterly》1997,(6):55-58
The results of field clinical trials of Russian and American yeast vaccines against hepatitis B are presented. The study revealed that both vaccines were faintly reactogenic, safe and exhibited high immunological activity. After the full course of immunization following the schedule 0-1-2 months 92.5% and 97.5% of patients receiving, respectively. Russian vaccine "Combiotech" and American vaccine "H-B-Vax II" were found to have specific antibodies. The maximum effect was registered when the vaccines were introduced according to the schedule 0-1-6 months. Seroconversions were observed in 97.5% and 100% of the vaccinees receiving the Russian and American vaccines respectively, in the latter case the highest antibody level being observed. The use of the vaccines within the prophylactic immunization schedule showed that antibodies to hepatitis B appeared in immunized children in 93-100% of cases. Seroconversion indices and the levels of antibodies to diphtheria, tetanus, poliomyelitis and measles were statistically significant and were the same in children receiving only the vaccines according to the immunization schedule and in children immunized, in addition to these vaccines, against hepatitis B. 相似文献
100.
Burova TV; Choiset Y; Tran V; Haertle T 《Protein engineering, design & selection : PEDS》1998,11(11):1065-1073
Mixed disulfide derivatives of bovine beta-lactoglobulin (BLG) were studied
by circular dichroism (CD), gel-permeation HPLC and high- sensitivity
differential scanning calorimetry (HS-DSC). It was shown that modification
of Cys121 with mercaptopropionic acid and mercaptoethanol does not affect
the secondary structure of BLG, but results instead in tertiary and
quaternary structure changes. At neutral pH, the equilibrium
dimer<==>monomer of modified beta- lactoglobulin is shifted towards
monomeric form. In contrast to native BLG, thermal denaturation of modified
beta-lactoglobulin is fully reversible in neutral and acidic pH as
demonstrated by CD and HS-DSC measurements. Modification of Cys121 results
in a significant decrease of transition temperature (-6 degrees C) and
enthalpy (-106 kJ/mol) at pH 2.05 while unfolding heat capacity increment
remains unchanged. Thermal unfolding transitions of native and modified
beta-lactoglobulin at pH 2.05 are well approximated by a two-state model
suggesting that no intermediate states appear after modification. The
difference in Gibbs energy of denaturation between native and modified
beta- lactoglobulin, 8.5 kJ/mol at 37 degrees C and pH 2.05, does not
depend on the nature of the introduced group (charged or neutral). Computer
analysis of possible interactions involving Cys121 in a three- dimensional
structure of beta-lactoglobulin revealed that the thiol group is too far
away from neighboring residues to form side-chain hydrogen bonds. This
suggests that the sulfhydryl group of Cys121 may contribute to the
maintenance of BLG tertiary structure via water mediated H-bonding.
相似文献