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81.
We observed that peripheral T cells activated in vivo or invitro by superantigens are susceptible to cell death when theirantigen receptor is cross-linked with the appropriate anti-ßTCR mAb. TCR ligation by mAbs specifically drove the T cellclonal deletion in both CD4+ and CD8+ cell subsets. An IL-2/1L-2Rinteraction seems to be a critical step In predisposing superantigenactivated cells to death; In fact, in vivo IL-2R bockade reversedT cell deletion In superantlgen plus anti-ß TCR mAbtreated mice. TCR ligatlon by mAbs also produced cell deathof the relevant targets in in vitro IL-2 activated T cells.Surprisingly, no T cell deletion was demonstrable in IL-2 activatedcells following staphylococcal enterotoxin B - TCR Interaction,ruling out the possibility that superantigen in Itself can inducecell death. Thus, while superantigen activation opens the celldeath program, a subsequent TCR-antigen (self) Interaction appearsnecessary to produce clonal deletion in mature T lymphocytes.  相似文献   
82.
83.
For noninvasive evaluation of anatomy and flow characteristics of internal mammary artery graft (IMA-graft), 2D echo-Color-Doppler (CDE) was performed in 60 patients (54 M, 6 F, mean age 54.1±6.9 y), who underwent coronary angiography 20.1 ±13 months after a coronary artery bypass graft (CABG).CDE was performed, using an echocardiographic unit equipped with a 5 MHz linear transducer.In all patients, measurements of IMA-graft diameter (mm), and peak systolic and diastolic flow velocity (cm/sec) were obtained at baseline and also in 16 patients after dipyridamole infusion (0.54 mg/Kg/min) and in 10 patients after sublingual nitroglycerin (NTG) (0.4 mg). Angiography showed the IMA-graft patency in 58/60 patients (96.8%).A typical biphasic flow was displayed by CDE in 49/58 patients (84.4%) with angiographic patency.Dipyridamole infusion increased both IMA-graft diameter and peak diastolic flow velocity (PDFV) from 2.28 ±0.51mm to 2.9 ±0.42mm and from 19.4 ±6.2 cm/sec to 93.9 ±29 cm/sec, respectively (p<0.0001).No significant modifications of peak systolic flow velocity (PSFV) were observed.NTG increased PDFV from 29.11 ±8 cm/sec to 41.88 ±7.20 cm/sec (p<0.005), while diameter and PSFV showed no statistically significant modifications.CDE is a useful diagnostic tool for noninvasive evaluation of IMA-graft patency both early after surgery and during long-term follow-up. CDE pharmacological stress improves the sensibility of the technique and it can provide indirect information about pathophysiology of recipient coronary vessel.  相似文献   
84.
Objectives To investigate the potential advantages of epidural anesthesia in an in vitro fertilization and embryo transfer program.Study Design Between January 1991 and December 1992, 148 infertile patients underwent transvaginal ultrasound guided oocyte retrieval. A total of 44 patients (group A) had 50 retrievals under epidural anesthesia, and 104 patients (group B, control group) 112 retrievals under intravenous sedation (propofol) with mask-assisted ventilation (nitrous oxide).Results In group A satisfactory anesthesia was achieved in 49 of the 50 cases (98%); one patient required additional intravenous administration of propofol owing to extreme anxiety. No complications were observed. Adversely, in group B nausea was observed in 16 cases (14%) and nausea and vomiting in 7 cases (6%). In group A the fertilization, cleavage and pregnancy rates were 67.2%, 92% and 20% respectively, while in group B the rates were 69.3%, 93% and 19.6% respectively; the differences are not statistically significant.Conclusions Epidural anesthesia is an effective method for transvaginal oocyte retrieval but does not improve the treatment outcome as compared to an intravenous sedation with mask-assisted ventilation using propofol and nitrous oxide.  相似文献   
85.
BACKGROUND: Clinically occult breast lesions are found with increasing frequency as a result of the widespread use of mammographic screening. METHODS: This study reports a new localization technique in which a small quantity of 99mTc-labelled colloidal albumin is inoculated directly into the lesion under stereotactic-radiographic or ultrasonographic guidance. Correct positioning of the inoculum is checked by scintigraphy. A gamma ray detection probe is then used to locate the lesion and guide its surgical removal. The results of this method in 30 patients were compared with those obtained using the established hook wire method in another 30 patients. RESULTS: In the wire localization group, the mean(s.d.) distance from the lesion centre to the specimen margin was 24.5(0.4) (range 15-45) mm. For the radioguided group the figures were 13.8(0.3) (range 5-25) mm. The mean(s.d.) lesion concentricity (difference between the maximum and minimum distance from the lesion border to specimen margin) was 6.2(0.4) (range 2-15) mm in the wire localization group and 3.8(0.2) (range 1-10) mm in the radioguided group. CONCLUSION: Use of a gamma probe allowed rapid, easy and accurate removal of occult breast lesions. In comparison to the hook wire method, radioguided removal allows reduced excision volume and better lesion centring within the specimen.  相似文献   
86.
The authors report their experience with a patient suffering from an intralobar bronchopulmonary sequestration (IBS). The lesion was misdiagnosed as metapneumonic lung abscess. IBS is a rare, diagnostically binding lung congenital malformation. So far, TC and MR angiography achieve pathognomonic findings with low invasivity. The best treatment of IBS could be surgical resection.  相似文献   
87.
(Received for publication on Apr. 28, 1997; accepted on May 15, 1998)  相似文献   
88.
Background: On the basis of our previous experience, we designed this study to determine the activity and toxicity of outpatient treatment with autologous tumor-infiltrating lymphocytes (TIL) together with intermediate-dose recombinant interleukin-2 (rIL-2) and low-dose recombinant interferon alfa-2a (rIFN-2a), for patients with metastatic melanoma.Methods: Between April 1992 and October 1994, we processed 38 melanoma samples derived from 36 patients with metastases. Proliferative cultures of expanded lymphocytes (TIL) were infused only once into patients with metastatic melanoma. rIL-2 was administered subcutaneously for 1 month, starting on the day of TIL infusion, at an escalating dose of 6–18 × 106 IU/m2/day for the first week and at the maximum-tolerated dose for the subsequent 3 weeks and then, after a 15-day interval, for 1 week/month for 3 months. rIFN-2a was administered subcutaneously at 3 × 106 IU three times each week until progression.Results: Of 38 melanoma samples, 19 (50%) resulted in proliferative cultures and were infused. The median number of expanded lymphocytes was 18 × 109 (range, 1–43 × 109), and the median period of culture was 52 days (range, 45–60). rIL-2 was administered at doses ranging between 6 and 18 × 106 IU/m2/day. Toxicity was mild or moderate, and no life-threatening side effects were encountered. Two of 19 treated patients experienced complete responses of their metastatic sites (soft tissue), 10 had stable disease, and 7 showed progressive disease. The response rate was 11% (95% confidence interval, 2–35%).Conclusions: Outpatient treatment with TIL plus rIL-2 and rIFN-2a is feasible, although, within the context of the small sample size, the activity of the combination was no different from the reported activity of any of the components used alone.  相似文献   
89.
· Background: The aim of this study was to evaluate the focal electroretinogram (FERG), an objective indicator of outer retinal function, in nonexudative age-related macular degeneration (NE-AMD), and to compare FERG results with morphological lesions assessed by stereoscopic fundus photographs and fluorescein angiograms. · Methods: Twenty-five patients (25 eyes) with bilateral NE-AMD (visual acuity of the study eyes ≥0.4) as well as 10 age- and sex-matched control subjects (10 eyes) were evaluated. FERGs were recorded from the macular region (9°) in response to sinusoidal stimuli flickered at 32 Hz. Amplitude and phase angle of the Fourier-analyzed FERG fundamental component were measured. Fundus lesions were graded from color slides according to the Wisconsin age-related maculopathy grading system [15]. Fluorescein angiograms were evaluated by an image analysis technique to compute the area with pathological hyperfluorescence (associated with drusen and/or retinal pigment epithelial atrophy) within the macular (approximately 9°×9°) region. · Results: Compared to control eyes, NE-AMD eyes had a reduction in the mean FERG amplitude (57% loss, P<0.001) with no phase changes. Amplitudes of individual affected eyes were negatively correlated with either the Wisconsin grading score (r=–0.63, P<0.001) or the percentage area of pathological hyperfluorescence (r=–0.70, P<0.01). Eyes with minimal NE-AMD lesions (Wisconsin score ≤6) and normal acuity had a lower mean amplitude (47% loss, P<0.05) than that of control eyes. · Conclusions: The results indicate that, in NE-AMD, the FERG is altered in parallel with the extent and severity of fundus lesions. However, a functional impairment of outer macular layers, which is detected by FERG losses, could precede morphological changes typical of more advanced disease. Received: 6 March 1998 Revised version received: 5 June 1998 Accepted: 17 June 1998  相似文献   
90.
Radioactive antibodies that react with tumour-associated antigens to "tag" antigen-positive tumour cell deposits were given to 20 patients with primary or recurrent colorectal cancer. The tumour associated antigen TAG 72-specific monoclonal antibody B72.3 labelled with 125-Iodine was used, and the radioactivity in the tumour was sought during operation with a hand-held gamma detecting probe. Tumour was detected by the probe in 7 of 15 patients with primary cancer, with a mean tumour: normal tissue ratio of 3.9, and in 4 of 5 patients with recurrent disease, with a mean tumour: normal tissue ratio of 2.0. Immunohistochemical analysis of surgical specimens confirmed the results of the intraoperative detection. The incidence of TAG 72-positive tumours (11/20, 55%), detected by immunohistochemistry, was lower than the 80% in the other series, possibly because of sampling errors or because the cases studied were uncomplicated with small primary tumours. Results obtained with the probe were instrumental in modifying the operation in two of the four "positive" patients with recurrences, allowing the removal of tumour masses that would otherwise have been overlooked.  相似文献   
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