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91.
92.
Twenty-six patients over the age of 50 years with proven iron deficiency anaemia were identified, investigated and followed up in general practice over a five-year period. The anaemia was symptomatic in 50% of patients but only 20% had symptoms related to the gut. Faecal occult blood testing was positive in five patients only and negative tests occurred in three patients with significant disease, including one caecal carcinoma. All patients agreed to oesophagogastroduodenoscopy (OGD) and fibreoptic sigmoidoscopy carried out on the same occasion. In eight patients, significant abnormalities were found on OGD and in two patients on sigmoidoscopy. Four patients declined barium enema examinations, two of whom had significant OGD abnormalities. Barium enema examination of the other 22 patients showed polyposis of the colon and a caecal carcinoma and initially missed one carcinoma of the caecum which was found subsequently. The likelihood of finding significant disease in iron-deficient patients over 50 years of age is high and should be assumed to be due to blood loss into the gut. Investigation by OGD, sigmoidoscopy and barium enema in the first instance seems warranted and is a condition that can be safely managed by the GP. (Br J Clin Pract 1997; 51(2) : 78-80)  相似文献   
93.
The amino acid sequence of guinea pig MSEL-neurophysin has been determined using tryptic peptides derived from the performic acid-oxidized protein and staphylococcal proteinase peptides obtained from the reduced-carboxamidomethylated neur-ophysin. Guinea pig MSEL-neurophysin consists of a 93-residue polypeptide chain that shows 12 substitutions and 2 deletions when compared to bovine MSEL-neurophysin. It displays the highest number of variations among known mammalian MSEL-neurophysins. These variations are mainly found in the C-terminal region (residues 88–93). Moreover guinea pig MSEL-neurophysin, like rat homologous protein, exhibits substitutions in positions 2, 5, 29 and 81 and lacks an arginine in the penultimate position. Comparison between eight mammalian MSEL-neurophysins reveals a highly conserved region (residues 1 to 88) and a hypervariable region (residues 89 to 93/95). On the other hand the eight species examined are endowed with arginine vasopressin except pig, which has a lysine vasopressin. In the vasopressin-MSEL-neurophysin precursor, the hormonal moiety and the MSEL region of neurophysin (residues 1–9) are encoded by a common exon in ox, rat and man; it can be concluded that this exon is evolutionarily conservative in contrast to the one encoding the C-terminal region of MSEL-neurophysin.  相似文献   
94.
Erythropoietin kinetics in rats: generation and clearance   总被引:1,自引:0,他引:1  
Steinberg  SE; Garcia  JF; Matzke  GR; Mladenovic  J 《Blood》1986,67(3):646-649
Detailed studies to analyze the early events of erythropoietin (Ep) secretion and clearance were performed in a rat model using a double antibody radioimmunoassay. Ep clearance was determined following intravenous injection of 1 mL of Ep-rich plasma, 1,080 mU/mL, obtained from phlebotomized rats. Analysis revealed a disappearance curve that conformed to a two-compartment model with an alpha half-life t1/2 of 3.6 minutes and a beta t1/2 of 86 minutes. The volume of distribution was similar to the calculated plasma volume. In anephric animals, there was no change in the plasma clearance rate or the volume of distribution. Rapid Ep secretion was elicited by a single 15 mL/kg phlebotomy (hematocrit decrement 45% to 30%), so that levels reached 20 to 30 times baseline (524 +/- 76 v 24 +/- 7 mU/mL) at five hours, whereas they plateaued for at least 33 hours. The increase in the rate of secretion was geometric, from 9.9 mU/h baseline secretion to 429 mU/h. These data identify a very sensitive and rapidly responsive system for Ep modulation in the rat.  相似文献   
95.
96.
This experiment examined the efficacy of an acustimulation wrist band for the relief of chemotherapy-induced nausea using a randomized three-arm clinical trial (active acustimulation, sham acustimulation, and no acustimulation) in 96 women with breast cancer who experienced nausea at their first chemotherapy treatment. Five outcomes related to wrist band efficacy (acute nausea, delayed nausea, vomiting, QOL, and total amount of antiemetic medication used) were examined. The five outcomes were examined separately using analysis of covariance controlling for age and severity of past nausea. There were no significant differences in any of these study measures among the three treatment conditions (P>0.1 for all). Study results do not support the hypothesis that acustimulation bands are efficacious as an adjunct to pharmacological antiemetics for control of chemotherapy-related nausea in female breast cancer patients.  相似文献   
97.
Linkage analysis was performed on a large pedigree with an autosomal dominant platelet disorder and a striking propensity in affected family members to develop hematologic malignancy, predominantly acute myelogenous leukemia. We report the linkage of the autosomal dominant platelet disorder to markers on chromosome 21q22. Four genetic markers completely cosegregate with the trait and yield maximum logarithm of difference scores ranging from 4.9 to 10.5 (theta = .001). Two flanking markers, D21S1265 and D21S167, define a critical region for the disease locus of 15.2 centimorgan. Further analysis of this locus may identify a gene product that affects platelet production and function and contributes to the molecular evolution of hematologic malignancy.  相似文献   
98.
Clonal rearrangements of the Ig heavy chain (IGH) locus occur in nearly all cases of B-cell precursor acute leukemia (BCP-ALL). Some of these rearrangements may be detected by polymerase chain reaction (PCR) using VH gene framework III (FRIII) and JH consensus primers. However, about 20% of BCP-ALLs fail to amplify with this technique. To determine the causes of these PCR failures and to investigate any possible association with specific subgroups of disease, we analyzed 72 acute leukemias of defined immunophenotype and cytogenetics, comparing FRIII with VH-family leader-specific PCR methods and Southern blotting. Of 37 BCP-ALL cases, 6 (16.2%) failed totally to amplify with FRIII and JH primers. None of these cases amplified with VH leader primers. Additionally, all cases retained germline VH6 genes and 5 of 11 rearranged alleles amplified with a consensus DH primer, indicating that these rearrangements represented biallelic DH-JH recombinations. Among the 6 FRIII and VH leader PCR-negative BCP-ALL cases, there was no common immunophenotype or consistent cytogenetic abnormality, although all showed structural chromosomal abnormalities and 3 of 5 successfully karyotyped had abnormalities of chromosome 12p. 13 cases with t(9;22)(q34;q11) Philadelphia chromosome-positive [Ph+]) and IGH rearrangements (9 BCP-ALL and 4 biphenotypic cases) were also analyzed. Of 23 rearranged IGH alleles, 19 (82%) were positive by FRIII PCR, and all 4 remaining alleles were amplified by VH leader primers. Use of the leader primers in these Ph+ cases also detected 3 additional clonal rearrangements that were not anticipated from Southern blotting; such unexpected bands were not observed in 21 other Ph- cases. The additional bands represented "new" and unrelated VH rearrangements rather than VH-VH replacement events. We conclude that biallelic DHJH rearrangements occur in a subgroup of BCP-ALL; in these cases, the activation of the full VHDHJH recombination mechanism had not occurred. Therefore, these cases of BCP-ALL were arrested at an early stage of B- cell differentiation. In contrast, all Ph+ BCP-ALLs and biphenotypic acute leukemias, which may represent the transformation of multipotent hemopoietic stem cells, had undergone VHDHJH recombination. Of 9 Ph+ BCP-ALL cases, 3 also showed ongoing VHDHJH rearrangement, reflecting the persistent expression of the VHDHJH recombinase. Finally, sequence analysis of 33 rearranged VHDHJH genes showed that only 3 including 2 Ph+ BCP-ALL maintained an intact open-reading frame. Loss of the open- reading frame occurred not only because of out-of-frame VHDH and DHJH joining, but also because of VH gene mutation and deletion. These data show that most BCP-ALLs may represent the neoplastic transformation of BCPs destined to die in the bone marrow.  相似文献   
99.

Background

Direct stenting without balloon dilatation may reduce procedural costs and duration, and hypothetically, the restenosis rate. This study was designed to compare the in-hospital and long-term outcomes of direct stenting (DS) versus stenting after pre-dilatation (PS) in our routine clinical practice.

Methods

The 1 603 patients treated with stenting for single coronary lesions were enrolled into a prospective registry. Patients with acute myocardial infarction (MI) within the preceding 48 hours, and those with highly calcified lesions, total occlusions, or a lesion in a saphenous graft were excluded. The baseline, angiographic and procedural data, inhospital outcomes and follow-up data were recorded in our database and analysed with appropriate statistical methods.

Results

Eight hundred and fifty-seven patients (53.5%) were treated with DS and 746 (46.5%) underwent PS. In the DS group, lesions were shorter in length, larger in diameter and had lower pre-procedural diameter stenosis. Type C and diffuse lesions and drug-eluting stents were found less often (p < 0.001). With univariate analysis, dissection and non-Q-wave MI occurred less frequently in this group (0.2 and 0.6% vs 3.9 and 2.1%, p < 0.001 and p = 0.01, respectively). However, the cumulative major adverse cardiac events (MACE) did not differ significantly (4.9 vs 4.6%, p = 0.79). With multivariate analysis, direct stenting reduced the risk of dissection (OR = 0.07, 95% CI: 0.01–0.33, but neither the cumulative endpoint of MACE (OR = 1.1, 95% CI = 0.58–2.11, p = 0.7) nor its constructing components were different between the groups.

Conclusions

Direct stenting in the real world has at least similar long-term outcomes in patients treated with stenting after pre-dilatation, and is associated with lower dissection rates.  相似文献   
100.
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