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131.
ST O'Sullivan MD FRCSI GT McGreal FRCS CM Reardon FRCSI DJ Hehir MCH FRCSI WO Kirwan MCH FRCSI MP Brady MCH FRCSI 《International journal of clinical practice》1997,51(5):289-292
During a four-year period, 308 patients presented following ingestion of foreign bodies. Ingestion was accidental in 272 cases (88.3%) and deliberate in the remainder. Symptoms at presentation included dysphagia, odynophagia, nausea and vomiting, chest pain and pharyngeal discomfort. Sixty-eight patients were asymptomatic. A policy of expectant management and selective endoscopy was employed. Following initial assessment 202 patients (65.6%) were discharged without treatment, 30 (9.7%) of whom were later reviewed as outpatients and did not require admission. Forty-nine patients (16%) were admitted for treatment; 27 had oesophagoscopy, five bronchoscopy and two had foreign body extraction with direct laryngoscopy. In nine patients who were endoscoped, no foreign body was identified. Twenty-seven others were referred to the otorhinolaryngology service in another hospital. There were no deaths in the group and morbidity was 1.2%. We conclude that a policy of selective endoscopy is safe and effective in the management of patients following ingestion of foreign bodies. 相似文献
132.
A single amino acid substitution in a common African allele of the CD4 molecule ablates binding of the monoclonal antibody, OKT4 总被引:1,自引:0,他引:1
S Lederman J A DeMartino B L Daugherty I Foeldvari M J Yellin A M Cleary N Berkowitz I Lowy N S Braunstein G E Mark 《Molecular immunology》1991,28(11):1171-1181
The CD4 molecule is a relatively non-polymorphic 55 kDa glycoprotein expressed on a subset of T lymphocytes. A common African allele of CD4 has been identified by non-reactivity with the monoclonal antibody, OKT4. The genetic basis for the OKT4- polymorphism of CD4 is unknown. In the present paper, the structure of the CD4 molecule from an homozygous CD4OKT4- individual was characterized at the molecular level. The size of the CD4OKT4- protein and mRNA were indistinguishable from those of the OKT4+ allele. The polymerase chain reaction (PCR) was used to map the structure of CD4OKT4- cDNAs by amplifying overlapping DNA segments and to obtain partial nucleotide sequence after asymmetric amplification. PCR was then used to clone CD4OKT4- cDNAs spanning the coding region of the entire, mature CD4 protein by amplification of two overlapping segments followed by PCR recombination. The nucleotide sequence of CD4OKT4- cDNA clones revealed a G----A transition at bp 867 encoding an arginine----tryptophan substitution at amino acid 240 relative to CD4OKT4+. Expression of a CD4OKT4- cDNA containing only this transition, confirmed that the arginine----tryptophan substitution at amino acid 240 ablates the binding of the mAb OKT4. A positively charged amino acid residue at this position is found in chimpanzee, rhesus macaque, mouse and rat CD4 suggesting that this mutation may confer unique functional properties to the CD4OKT4- protein. 相似文献
133.
SANMIGUEL CP HAGIIKE M MINTCHEV MP DELA CRUZ R PHILLIPS E CUNNEEN SA CONKLIN JL SOFFER EE 《Neurogastroenterology and motility》2006,18(6):484-485
Background: Electrical stimulation (ES) of the stomach has been shown to modulate LESP. Electrical stimulation, using neural high frequency stimulation (NGES) can induce contractions of the smooth muscle of the gut. The purpose of this study was to determine if electrical stimulation of the LES can affect LESP. Methods: Four female hound dogs, weight: 20–25 kg, underwent an esophagostomy that allowed the introduction of a sleeve manometry catheter into the esophagus. They were also implanted with a pair of electrodes along the longitudinal axis of the LES. After 3 weeks of recovery, they underwent esophageal manometry recording during control and ES, performed randomly on separate days, using 4 different stimulations: 1‐Low frequency: freq: 6 cycles/min, pulse: 350 milisec, amp: 5 mAmp; 2 High‐frequency: freq: 50 Hz, pulse: 1 milisec, amp: 5 mAmp; 3‐ NGES: freq: 50 Hz, pulse:20 milisec, amp:10 volts; 4‐ High‐frequency, circular: freq: 20 Hz, pulse:1 milisec, amp:5 mAmp. All recordings were performed 1 hour after consumption of 3 ounces of canned dog food, to prevent fluctuations in LESP and under mild sedation (acepromazine 0.5 mg kg1). Tests consisted, during ES days, of 3 periods of 20 minutes each: control , stimulation and post stimulation. The effect of NGES was also tested under anesthesia and following administration of L‐NAME 50 mg kg1 IV. and also atropine 0.05 mg kg1 IV. Analysis: area under the curve (AUC) and pressure were compared among the 3 periods. Data shown as mean ± SD, ANOVA and t‐test, p < 0.05. Results: Sustained increase in LESP was observed during low frequency stimulation, 32.1 ± 12.8 vs. 42.4 ± 18.0 vs. 50.1 ± 23.6, control vs. stimulation vs. post stimulation respectively, p = 0.013. AUC also significantly increased during and after stimulation, 39,320.3 ± 15,722 vs. 51,294 ± 21,826 vs. 59,823.6 ± 28,198.4 mmHgxsec, control vs. stimulation vs. post stimulation respectively, p = 0.01. There was no significant change with other types of ES. NGES induced an initial rise in LESP followed within few seconds by relaxation with slow resumption of pressure over a 1 minute period. L‐NAME increased LESP and augmented the initial rise in LESP following NGES but markedly diminished or abolished the relaxation phase. Atropine lowered LESP and abolished the initial rise in LESP induced by NGES. Conclusions: Low frequency ES of the LES increases LESP in conscious dogs. NGES has dual effect on LESP: an initial stimulation, cholinergically mediated, followed by relaxation mediated by nitric oxide. 相似文献
134.
AIMS: Intrauterine exposure to diabetes is a significant determinant of the development of obesity and early onset of Type 2 diabetes mellitus in the offspring. Both conditions are characterized by insulin resistance and the latter is associated with reduced membrane arachidonic and docosahexaenoic acids. Hence, we investigated if the membrane arachidonic and docosahexaenoic acids are depressed in the cord blood of babies born to women with gestational diabetes. METHODS: Cord (fetal) and maternal blood were obtained at delivery from control subjects (n = 33) and women with gestational diabetes (n = 40) and analysed for plasma triglycerides and cholinephosphoglycerides, and erythrocyte choline- and ethanolaminephosphoglycerides fatty acids. RESULTS: Babies of gestational diabetic mothers had reduced docosahexaenoic acid in the plasma (5.9 +/- 1.4 vs. 7.1 +/- 2.0, P < 0.01) and erythrocyte (4.0 +/- 2.2 vs. 5.4 +/- 2.9, P < 0.05) cholinephosphoglycerides. Moreover, the total omega-6 and omega-3 fatty acids of the erythrocyte cholinephosphoglycerides were significantly lower (P < 0.05) in these babies. A similar trend was observed in plasma triglycerides and erythrocyte ethanolaminephosphoglycerides. The maternal plasma triglycerides and erythrocyte ethanolaminephosphoglycerides fatty acids profile were not different between the two groups. However, there was a reduction in arachidonic acid and total omega-6 fatty acids in the erythrocyte cholinephosphoglycerides of the gestational diabetic women. CONCLUSION: The altered plasma and erythrocyte fatty acids in the cord blood of babies born to women with gestational diabetes suggests a perturbation in the maternal-fetal nutrient transport and/or fetal lipid metabolism. 相似文献
135.
TM Sankary ; G Yang ; JM Romeo ; PP Ulrich ; MP Busch ; BD Rawal ; GN Vyas 《Transfusion》1994,34(8):656-660
BACKGROUND: Since screening for antibody to hepatitis C virus (HCV) was introduced in 1990, posttransfusion hepatitis has been reduced to nearly background levels. This has led to reconsideration of the value of testing donated blood for elevated alanine aminotransferase (ALT). The contribution of ALT testing in detecting seronegative infection was evaluated by the performance of polymerase chain reaction (PCR) for hepatitis B virus (HBV) or HCV in plasma from ALT-elevated blood units. STUDY DESIGN AND METHODS: Testing was performed on 375 units of plasma, derived from an equivalent of 47,500 blood donations, with a highly sensitive hemi-nested PCR procedure. Using a triplet of primers directed at the conserved regions of HBV DNA and 5'-noncoding regions of HCV RNA, the hemi-nested PCR assay can reliably amplify 10 viral molecules to levels detectable in ethidium bromide-stained agarose gels. Pools of plasma from groups of four donors were screened with hemi-nested PCR. For any reactive pools, the plasma from individual donors was retested twice on different aliquots. RESULTS: Two of 375 units, both with midrange ALT elevation, were repeatedly reactive in hemi-nested PCR (one each for HBV DNA and HCV RNA). However, samples from the two suspect donors tested 9 and 5 months later revealed no seroconversion, elevated ALT, or viral genomes in hemi-nested PCR. CONCLUSION: The lack of confirmed HBV or HCV infection in this study representing an estimated 47,500 voluntary blood donations suggests that routine ALT testing for further prevention of posttransfusion hepatitis after exclusion of HBV- and/or HCV-seropositive blood may be superfluous. 相似文献
136.
137.
Penicillin-induced effects on streptomycin uptake and early bactericidal activity differ in viridans group and enterococcal streptococci. 总被引:2,自引:5,他引:2
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M H Miller M A el-Sokkary S A Feinstein F D Lowy 《Antimicrobial agents and chemotherapy》1986,30(5):763-768
In vitro studies with penicillin and [3H]streptomycin in four strains of streptococci (S. faecalis, S. sanguis, and S. mitis) were performed by simultaneously measuring the rates of bacterial killing and uptake of streptomycin. In S. faecalis, penicillin stimulated streptomycin uptake, as has been shown by Moellering and Weinberg (R. C. Moellering, Jr., and A. N. Weinberg, J. Clin. Invest. 50:2580-2584, 1971). Moreover, the antibiotic combination was associated with an enhanced bactericidal rate which temporally correlated with beta-lactam-induced aminoglycoside uptake. In contrast, in viridans group streptococci (S. sanguis and S. mitis) penicillin had no effect on streptomycin uptake and a minimal effect on bactericidal rate when compared with either drug alone. These data suggested that the stimulation of streptomycin uptake in streptococci by penicillin is strain or species specific and that important differences exist between enterococci and viridans group streptococci regarding the mechanisms of beta-lactam-aminoglycoside potentiation. 相似文献
138.
Mouse cells transformed by bovine papillomavirus contain only extrachromosomal viral DNA sequences. 总被引:35,自引:2,他引:35
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M F Law D R Lowy I Dvoretzky P M Howley 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(5):2727-2731
The viral DNA sequences in mouse C127 cells transformed by bovine papillomavirus type 1 (BPV-1) virions, by full-length linear BPV-1 DNA, or by a defined transforming subgenomic DNA segment of BPV-1 were examined by reassociation kinetics and blot hybridization. In all cases, the transformed cells contained multiple copies of BPV-1 DNA, present exclusively as supercoiled or nicked circular extrachromosomal molecules or as a slowly migrating complex of circular viral DNA molecules. In the transformed cell lines established from cells transfected with full-length linear BPV-1 DNA, there was recircularization of the input DNA which in some cases resulted in the loss of the restriction site used in the linearization of the DNA. In the transformed cell lines established with the defined subgenomic segment there was circularization of the DNA accompanied by the acquisition of new sequences or duplication and rearrangement of the BPV-1 sequences. In contrast to other well-studied virus transformation systems, no integration of the BPV-1 genome into the host chromosome could be detected under conditions sensitive enough to detect 0.1-0.2 viral genome equivalent. It was concluded that maintenance of transformation may be mediated by nonintegrated viral DNA. 相似文献
139.
Mepacrine uptake into platelets and bone marrow megakaryocytes was analyzed to further characterize the dense granule defects in a group of seven mouse pigment mutants that have characteristics of platelet storage pool disease (SPD). In contrast to our previous studies using electron microscopy, this method revealed that all mutants had normal numbers of dense granules. However, total mepacrine uptake in all mutant platelets was significantly diminished to less than 50% of normal uptake. Also, the flashing phenomenon observed when normal dense granules are irradiated with ultraviolet light was either greatly diminished or absent when platelets of individual mutants were similarly irradiated. Therefore the principal defect in the mutant platelets is an inability to accumulate dense granule contents rather than an absence of the granules. Mepacrine uptake into megakaryocytes was indistinguishable in normal and mutant mice. This indicates the mutant dense granule defects appear either very late in megakaryocyte development or early in platelet formation in correlation with development of the mature dense granule. By standard transmission electron microscopy we have not been able to detect gross structural or subcellular abnormalities in either platelets or megakaryocytes of mutant mice. It appears all seven mutants produce immature or functionally abnormal dense granules. 相似文献
140.
Pullen DJ; Sullivan MP; Falletta JM; Boyett JM; Humphrey GB; Starling KA; Land VJ; Dyment PG; Vats T; Duncan MH 《Blood》1982,60(5):1159-1168
In an attempt to improve the poor outlook for children with T-cell leukemia (T-ALL), the Southwest Oncology Group, Pediatric Division, used a modified LSA2-L2 multidrug regimen to treat 53 patients with E- rosette-positive T-ALL. This regimen was chosen because of its demonstrated efficacy in T-cell (mediastinal) non-Hodgkin's lymphoma. Complete remission (CR) rate was 88%. Range of follow-up for those patients remaining in CR is 24-49 mo (median 39 mo). Life table analysis estimates that 40% (SE 8.3%) of all patients who started induction therapy will remain failure-free at 3 yr. For patients achieving CR, 46% (SE 9%) are projected to remain in both marrow and extramedullary CR at 3 yr. Median failure-free duration was 13 mo, but only 1 patient has relapsed beyond 16 mo. Twenty-nine percent of initial relapses were isolated CNS relapses. The following presenting factors did not relate significantly to outcome: hemoglobin, platelet count, uric acid, race, and mediastinal mass. Age greater than 10 yr was a poor prognosis indicator only in the less than 50,000/microliter WBC group. Sex was not a significant factor after adjusting for WBC. WBC was the most important prognostic factor: 19% (SE 8%) of patients with WBC greater than 50,000/microliter are projected to remain failure- free at 3 yr as compared to 67% (SE 11%) of patients with WBC less than 50,000/microliter. Although the overall results are better than those previously reported for pediatric patients with T-ALL, the long-term failure-free rate remains low for patients presenting with greater than 50,000/microliter WBC. 相似文献