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71.
72.
W D Rees S M Hay V Buchan C Antipatis R M Palmer 《The British journal of nutrition》1999,81(3):243-250
Maternal protein deficiency causes fetal growth retardation which has been associated with the programming of adult disease. The growth of the rat fetus was examined when the mothers were fed on diets containing 180, 90 and 60 g protein/kg. The numbers of fetuses were similar in animals fed on the 180 and 90 g protein/kg diets but the number was significantly reduced in the animals fed on the 60 g protein/kg diet. The fetuses carried by the mothers fed on the 90 g protein/kg diet were 7.5% heavier than those of mothers fed on 180 g protein/kg diet on day 19 of gestation, but by day 21 the situation was reversed and the fetuses in the protein-deficient mothers were 14% smaller. Analysis of the free amino acids in the maternal serum showed that on day 19 the diets containing 90 and 60 g protein/kg led to threonine concentrations that were reduced to 46 and 20% of those found in animals fed on the control (180 g/kg) diet. The other essential amino acids were unchanged, except for a small decrease in the branched-chain amino acids in animals fed on the 60 g protein/kg diet. Both low-protein diets significantly increased the concentrations of glutamic acid+glutamine and glycine in the maternal serum. On day 21 the maternal serum threonine levels were still reduced by about one third in the group fed on the 90 g protein/kg diet. Dietary protein content had no effect on serum threonine concentrations in nonpregnant animals. Analysis of the total free amino acids in the fetuses on day 19 showed that feeding the mother on a low-protein diet did not change amino acid concentrations apart from a decrease in threonine concentrations to 45 and 26% of the control values at 90 and 60 g protein/ kg respectively. The results suggest that threonine is of particular importance to the protein-deficient mother and her fetuses. Possible mechanisms for the decrease in free threonine in both mother and fetuses and the consequences of the change in amino acid metabolism are discussed. 相似文献
73.
Dziri C Paquet JC Hay JM Fingerhut A Msika S Zeitoun G Sastre B Khalfallah T 《Journal of the American College of Surgeons》1999,188(3):281-289
BACKGROUND: Omentoplasty (OP) is thought to fill residual cavity, to assist healing of raw surfaces, and to promote resorption of serosal fluid and macrophagic migration in septic foci. Results published to date, whether retrospective or prospective, are not controlled and are discordant. STUDY DESIGN: The authors investigated whether OP, either filling the residual cavity after unroofing, or covering the hepatic raw surface after pericystectomy, could reduce the rate or severity of deep abdominal complications (DAC) after surgical treatment of hydatid disease of the liver. Between January 1993 and December 1996, 115 consecutive patients (51 males and 64 females, mean age 42+/-16 years [range 10 to 80 years]) with previously unoperated uni- or multilocular hydatid disease of the liver, complicated or not, without other abdominal hydatid disease, were randomly allotted to OP (n = 58) or not (NO) (n = 57) after unroofing, total, or partial pericystectomy. Patients were divided into 2 strata according to the site of the cyst with respect to the diaphragm: a) posterosuperior segments II, VII, and VIII or b) anterior segments III, IV, V, and VI. Main outcomes measures included deep bleeding, hematoma, infection, or bile leakage. Subsidiary measures included wound complications, extraabdominal complications, duration of operation, and length of hospital stay. RESULTS: Both groups were comparable regarding patient demographics, cyst characteristics, intraoperative procedures, search for bile leaks, and intraoperative transfusion requirements. On the other hand, more patients (86%) in NO had associated drainage of the abdominal cavity than in OP (64%) and the duration of operation was 9 minutes longer in OP, but neither of these differences was statistically significant. Less DAC occurred in OP (10%) than in NO (23%) (a posteriori gamma risk < 0.05) and fewer deep abdominal abscesses (0 versus 11%) (p < 0.03). Median duration of hospital stay, however, was similar. CONCLUSIONS: OP decreases the rate of DAC and especially deep abdominal abscess after surgical treatment (unroofing or pericystectomy) for hydatid disease of the liver and should be recommended in this setting. 相似文献
74.
Type 1 von Willebrand disease (vWD) is an autosomal dominant bleeding disorder of variable penetrance. It is characterised by a mild to moderate bleeding tendency and a quantitative deficiency of von Willebrand factor (vWF) with the full range of vWF multimers. Few mutations have been described which account for the mode of inheritance in dominant vWD type 1. We screened the vWF multimerization domains (regions D1-D3 of the vWF gene) of 12 unrelated patients with dominant vWD type 1 to investigate the hypothesis that multimerization of vWF sub-units may be inhibited or reduced by a "dominant negative" mechanism. Platelet-derived RNA was reverse transcribed and the resulting vWF cDNA amplified by the polymerase chain reaction (PCR) in a series of overlapping fragments. These were subjected to a combination of single-strand conformation polymorphism (SSCP) and heteroduplex analysis. This approach identified mobility shifts on acrylamide gels that represented 12 distinct SSCP and/or heteroduplex patterns in our patient group. DNA sequencing of the region encompassing each mobility shift showed these variants to represent previously described polymorphisms within the vWF coding sequence. Examination in all 12 patients for the previously described G3389T and T3445C mutations proved negative. The molecular pathology of classical type 1 vWD remains enigmatic, mutations having been identified in only a small minority of patients. A common mechanism underlying this disease state has still to be elucidated. 相似文献
75.
van Kammen DP McAllister-Sistilli CG Kelley ME Gurklis JA Yao JK 《Psychiatry research》1999,87(2-3):129-136
Interleukin 6 (IL-6) levels have been shown to be increased in a number of autoimmune disorders and have recently been shown to be elevated in the serum of schizophrenic patients. Given the involvement of the CNS in schizophrenia, levels of interleukin-6 in the CSF are also of interest. Thus, we examined levels of both CSF and serum IL-6 concomitantly to determine if these levels were different from control values. In addition, we examined these measures in patients both on and off antipsychotic drugs to determine if any medication or exacerbation effects may account for the difference from controls. CSF IL-6 was measured by ELISA in 61 drug-free male schizophrenic (DSM-IIIR) patients and 25 well-screened healthy male control subjects. Serum IL-6 was measured in 43 of the 61 patients, and in 16 control subjects. Serum IL-6 was significantly higher in the schizophrenic patients compared to control subjects. CSF IL-6 was also higher in the patients, but the difference was not statistically significant. Paired data showed no medication or exacerbation effects on CSF IL-6, but plasma IL-6 significantly decreased in patients that experienced an exacerbation after medication withdrawal. The results indicate that IL-6 levels may be altered in schizophrenia. The relative decrease in exacerbated patients following haloperidol withdrawal may be indicative of a compensatory response of plasma IL-6 levels to relapse. 相似文献
76.
Wickramasekera D Hay DJ Fayz M 《Journal of the Royal College of Surgeons of Edinburgh》1999,44(1):59-60
A young women presented with non-resolving acute small bowel obstruction and was found to have a stricture in the distal ileum at laparotomy. Histologically this was due to endometriosis. Resection of the involved segment gave excellent results. 相似文献
77.
78.
D. W. P. Hay Mark A. Luttmann Roseanna M. Muccitelli Roy G. Goldie 《Naunyn-Schmiedeberg's archives of pharmacology》1999,359(5):404-410
Tension and phosphatidyl inositol (PI) turnover experiments were conducted to investigate the receptors and signal transduction
pathways responsible for contractions elicited by endothelin (ET) ligands in human bronchus. Nicardipine (1 μM), the L-type
calcium channel inhibitor, or incubation in Ca2+-free medium, produced marked inhibition of contractions to the ETB receptor-selective agonist, sarafotoxin S6c, and especially those induced by KCl. In contrast, Ca2+-free medium was without appreciable effect against contraction produced by endothelin-1 (ET-1), the non-selective ETA and ETB receptor agonist. In Ca2+-free medium, ryanodine (10 μM), which inhibits intracellular calcium mobilization, reduced sarafotoxin S6c- and ET-1-induced
responses, but was without effect on responses to KCl. Similarly, nickel chloride (Ni2+; 1 mM) caused marked inhibition of contractions induced by sarafotoxin S6c or ET-1, but had no significant effect on KCl
concentration-response curves. The mixed ETA/ETB receptor antagonist SB 209670 (3 μM) inhibited responses to sarafotoxin S6c and ET-1 such that concentration-response curves
were shifted rightward, at the 30% maximum response level, by 10.0- and 3.8-fold, respectively, whereas BQ-123 (3 μM), the
ETA receptor antagonist, was without effect on responses induced by either agonist. ET-1 (1 nM–0.3 μM) caused a concentration-dependent
stimulation of PI turnover, whereas sarafotoxin S6c (0.3 nM–0.1 μM) induced only small and variable increases, except at the
highest concentration. The increase in PI turnover evoked by ET-1 was inhibited by SB 209670 (3 μM), and also by BQ-123 (3
μM). This is consistent with linkage of ETA receptors to activation of inositol phosphate generation in human bronchial smooth muscle cells. Collectively, the data suggest
that differences exist in the relative contributions of intracellular and extracellular Ca2+ mobilization mechanisms elicited by ETA and ETB receptor activation. Thus, sarafotoxin S6c-induced, ETB receptor-mediated contraction in human bronchial smooth muscle appears to be dependent, in part, upon extracellular Ca2+, although a significant component of the response was also mediated by intracellular Ca2+ release, including from ryanodine-sensitive stores. ETA receptor-mediated contraction of human airway smooth muscle was activated largely via the release of intracellular Ca2+.
Received: 21 July 1998 / Accepted: 26 January 1999 相似文献
79.
M F Herrera I D Hay P S Wu J R Goellner J J Ryan J R Ebersold E J Bergstralh C S Grant 《World journal of surgery》1992,16(4):669-74; discussion 774-5
The latest World Health Organization International Classification defines papillary thyroid carcinoma by its "follicular cell differentiation...as well as characteristic nuclear changes". However the oxyphilic (Hürthle cell) papillary carcinoma have nuclei which generally resemble the nuclei seen in oxyphilic follicular carcinomas, and such oxyphilic papillary tumors may behave more aggressively than typical papillary cancers. To further characterize these rare tumors, we identified during a 32-year period 22 patients with oxyphilic papillary cancer and compared them with 1,084 patients with typical papillary cancers and 57 patients with oxyphilic follicular cancers treated by the Mayo surgical group during the same time period. Although typical papillary and oxyphilic papillary cancers were comparable with regards to patient age, tumor size and extent, TNM stage, and prognostic score (AGES), there were significant differences. Compared to typical papillary tumors, oxyphilic papillary cancers had fewer neck nodal metastases at primary diagnosis (5% vs 40%, p less than 0.0001), were more often DNA non-diploid (71% vs 21%, p less than 0.001), and after 10 postoperative years had higher rates of both tumor recurrence (28% vs 11%, p less than 0.0001) and cause-specific mortality (1.7% vs 4%, p less than 0.0005). In these four important respects the oxyphilic papillary cancers more resembled the oxyphilic follicular cancers. For oxyphilic follicular cancers, the frequency of initial neck nodal metastases was 7% (cf 5%); 83% of the oxyphilic follicular tumors were non-diploid (cf 71%), and at 10 years postoperatively the tumor recurrence and cause-specific mortality rates were 28% and 18%, insignificantly different from 28% and 17% seen with the oxyphilic papillary cancers.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
80.
Rheumatoid factors and complex formation. The role of light-chain framework sequences and glycosylation 总被引:2,自引:0,他引:2
New information regarding rheumatoid factors (RFs) indicates that the RFs synthesized in synovium and lymphoid tissues of patients with rheumatoid arthritis (RA) are different from monoclonal and nonspecific RFs associated with other inflammatory states. The characteristics of RF associated with RA are as follows. They are of all Ig isotypes (not just IgM), indicating T-cell participation in antibody maturation. They have higher avidity for human IgG than for rabbit IgG. They use the human germline heavy-chain variable region (VH) gene VHIII more frequently than other VH genes, and light chains from multiple families. (In contrast, monoclonal RFs use predominantly VH1 and very commonly the V kappa IIIb germline gene HUMkv325). RA IgG is somatically mutated. (In contrast, monoclonal RFs use unmutated germline Ig genes). This suggests they are matured by stimulation either with specific antigens or other activation signals such as cytokines. They are abnormally glycosylated. In general, during periods of disease activity in adult and juvenile RA, a galactose is missing from the Fc of the IgG molecule, leaving an empty "pocket" between the C gamma 2 domains of heavy chains. The IgG RFs self-associate. This may result at least in part when galactose on the F(ab')2 portion of one IgG molecule fills the empty pocket in the Fc of another Ig molecule. Self-association forms immune complexes capable of fixing complement and probably of causing joint damage and vasculitis. 相似文献