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81.
目的 测定血清可溶性幽门螺杆菌抗原(S-Hp)和其特异性免疫复合物(Hp-IC)并评价它们对幽门螺杆菌感染诊断的意义.方法 采用双抗体夹心式酶免疫测定法.结果 66例Hp感染患者血清S-Hp阳性率90.91%,显著高于28例阴性对照组阳性率0%,P<0.001.S-Hp含量与Hp感染菌量呈成比,但43例Hp阳性患者治疗前后S-Hp 含量无显著改变(P>0.05).血清 S-Hp抗原均以IgG和/或IgA型特异性免疫复合物形式存在,Hp-IC对Hp感染诊断特异性85.71%,敏感性77.23%. 结论 S-Hp和Hp-IC测定可用于临床Hp感染诊断,对阐明Hp致病机理有重要意义.  相似文献   
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A molecular basis for hemoglobin-H disease in American blacks   总被引:4,自引:0,他引:4  
We have applied gene counting and restriction endonuclease mapping techniques to the study of two American black families in which there were one or more cases of HbH disease. We found deletions of three of the four normal alpha-globin genes in individuals with HbH disease. In two of these individuals, the chromosome containing the single alpha gene could have originated by crossing over between mispaired alpha genes, resulting in a deletion of about 4.2 kilobases (kb).  相似文献   
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We investigated whether impaired duodenal mucosal prostaglandin E2 (PGE2) production previously observed in duodenal ulcer (DU) was a primary pathophysiological abnormality or secondary to mucosal architectural changes that accompany ulceration. One hundred patients were studied: at endoscopy, paired duodenal biopsies were taken in patients with normal endoscopies and from the ulcer edge or scar and background mucosa in active or healed DU. One of the pair of biopsies was used to estimate PGE2 synthesis ability, the other was processed for histology and histochemistry. The following features graded: goblet cell numbers and staining with Periodic acid-Schiff reagent (PAS), epithelial staining with PAS, villous atrophy, columnar cell height, inflammatory cell infiltrate and micro-erosions and gastric metaplasia taken as a whole. Patients were found to have normal endoscopy (n= 31), active untreated DU (n= 20), active DU on treatment with either cimetidine or ranitidine (n= 13), healed DU on maintenance treatment (n= 27) and healed DU off treatment (n= 9). Active duodenal ulceration was found to be associated with decreased numbers of goblet cells, loss and blunting of villi, increased columnar cell height, increased epithelial cell PAS staining and with gastric metaplasia. After healing, only villous blunting remained. These changes were present, but less marked, at sites removed from the ulcer and were not apparent in the patient groups with healed ulcers. A strong correlation between overall gastric metaplasia and epithelial cell PAS staining and the reduced ability to synthesize PGE2 (P < 0.001) was only apparent when biopsies from all patients were grouped together, but not within individual patient subgroups. There was no consistent correlation between PGE2 generation and individual parameters of pathological change in the duodenum. We conclude that, although inflammatory and mucosal changes may contribute, the evidence suggests that the impaired PGE2 generation in DU disease is, to a large extent, independent of histological and histochemical features.  相似文献   
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Chordoma: role of radiation therapy   总被引:4,自引:0,他引:4  
The treatment of 21 patients with a diagnosis of chordoma seen over a 20-year period is described. The 13 men and eight women (ratio 1.6:1) ranged in age from 7 to 82 years (average, 50 years). Eleven chordomas arose from the clivus; the others originated in the sacral region (three patients), thoracic spine (one), cervical spine (three), and lumbar spine (three). Primary treatment consisted of surgery, reserving radiation therapy for recurrence in the majority of patients. Radiation doses, delivered with megavoltage equipment, ranged between 5,000 cGy delivered over 5 weeks and 6,600 cGy over 6 1/2 weeks. Irradiation produced significant tumor control, with remission of symptoms from 1 to 6 years. The combination of high-dose radiation therapy and complete or subtotal surgical resection offers the best chance for prolonged survival in this group of patients.  相似文献   
90.
A recently developed method for image-selected localized hydrogen-1 magnetic resonance (MR) spectroscopy was assessed in the differential diagnosis of nine primary and secondary cerebral tumors, including four gliomas, two meningiomas, one neurilemoma, one arachnoid cyst, and one metastasis of breast cancer. Well-resolved H-1 MR spectra of these tumors were obtained in vivo with a conventional 1.5-T whole-body MR imaging system. All tumor spectra were remarkably different from spectra from normal brain tissue. Spectra obtained from different tumors exhibited reproducible differences, while histologically similar tumors yielded characteristic spectra with only minor differences. The observed spectral alterations reflect variations in concentrations and relaxation times of the H-1 MR sensitive pool of free (mobile) metabolites within the tissues. In most cases, the concentrations of N-acetyl-aspartate and creatine/phosphocreatine are reduced below detectability, whereas choline-containing compounds are generally enhanced. The spectral differences between the tumors are mainly due to the differing concentrations of lipids, lactic acid, and carbohydrates. Localized H-1 MR spectroscopy may become an important clinical tool for the differentiation of tumors as well as for therapeutic control.  相似文献   
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