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991.
The recombinant DNA-derived, human immunodeficiency virus (HIV) antigen-based immunoblot assay (RIBA-HIV216) is a new supplemental (confirmatory) test developed to detect antibodies to HIV-1. The assay employs four recombinant viral antigens, corresponding to HIV-1 p24, p31, p41 and gp120 proteins, in an immunoblot format. With this assay, HIV-1 antigen reactivity was detected in all 683 infected patient serum or plasma specimens evaluated; 665 (97.6%) of these sera met the criteria for a positive interpretation, and 18 (2.6%) were classified as indeterminate. All 683 samples reacted with the recombinant gp41-equivalent protein. The first sequential enzyme immunoassay (EIA)-reactive samples collected from 33 seroconverting homosexual men reacted on RIBA-HIV216. Eleven (1.1%) of 999 EIA-negative blood donor sera reacted weakly with a single recombinant antigen (p24 or p31), whereas 13 to 48 percent had indeterminate reactions on viral lysate Western blots. One (1.5%) of 66 EIA-positive, Western blot-negative blood donor samples and 19 (29%) of 66 EIA-positive, Western blot-indeterminate blood donor samples scored indeterminate on RIBA-HIV216. Nonspecific reactivity was seen with only 1 (0.8%) of 114 patient sera containing possible interfering antibodies, whereas 33 percent of these samples had indeterminate reactions on Western blot and 35 percent had equivocal reactions on immunofluorescence assay (IFA). We conclude that the RIBA-HIV216 is approximately as sensitive as and significantly more specific than virus-derived Western blot and IFA. The RIBA-HIV216 also allows for semiquantitation of specific antibodies that may be of value in clinical staging and therapeutic monitoring.  相似文献   
992.
Focal segmental necrotizing glomerulonephritis in rheumatoid arthritis   总被引:3,自引:0,他引:3  
We report ten patients with rheumatoid arthritis (RA) who developed a focal segmental necrotizing glomerulonephritis (FSNGN) and extracapillary proliferation typical of vasculitic glomerulonephritis. Five patients also had extrarenal vasculitis. Renal presentation was with renal impairment (n = 9) (median creatinine 726 mumol/l, range 230- 1592 mumol/l), microscopic haematuria (n = 8) and proteinuria (n = 10). Nine patients were seropositive for rheumatoid factor and nine had bone erosions. Serum from four of five patients tested by indirect immunofluorescence was positive for antineutrophil cytoplasmic antibody (ANCA) with perinuclear staining. Only three patients had penicillamine or gold therapy. Treatment was with prednisolone and cyclophosphamide (six patients, two of whom were also plasma-exchanged), prednisolone and azathioprine (two patients) and prednisolone alone (two patients). There was a marked improvement in renal function in eight patients. Two patients with dialysis-dependent renal failure recovered renal function, although in one patient this was transient and she required further dialysis 4 months later. Two other patients progressed to dialysis at 3 months and 1 year respectively. Four patients died, one remains dialysis-dependent, and four continue to have good renal function at 5 year follow-up (median creatinine 148.5 mumol/l, range 120-193 mumol/l). One patient was lost to follow-up at 5 years. FSNGN should be considered in all patients with RA and renal impairment, proteinuria and/or microscopic haematuria. This diagnosis appears to be more likely in patients with clinical extrarenal vasculitis, bone erosions or who are seropositive. In these cases, an urgent renal biopsy is indicated.   相似文献   
993.
In some alcohol-related pathologies of chronic alcoholism women are more vulnerable than men. A consecutive sample of 62 chronic alcoholics was studied, 18 females and 44 males, aged between 28 and 69 years to assess the incidence and distribution of peripheral neuropathy with regard to gender. All patients underwent clinical and neurological observations, laboratory tests, and electroneurography. Total lifetime dose of ethanol (TLDE) and other risk factors for neuropathy (disease duration, age, nutritional status) were calculated and correlated to sural nerve sensory-evoked potential (SEP) amplitude. In 42 patients (67.7%), we observed the presence of clinical and/or infraclinical neuropathy, mostly axonal, in 29 males (65.9%) and 13 females (72.2%). In women, compared to men, TLDE and disease duration were significantly inversely correlated to sural nerve SEP amplitude, i.e in women, SEP amplitude is significantly reduced in relation to TLDE and disease duration increase. These data indicate a higher sensitivity of females towards the toxic effects of ethanol, other than malnutrition, on peripheral nerve fibres.  相似文献   
994.
995.

Background

Left ventricular hypertrophy (LVH) is a hallmark of chronic pressure or volume overload of the left ventricle and is associated with risk of cardiovascular morbidity and mortality. The purpose was to evaluate different electrocardiographic criteria for LVH as determined by cardiovascular magnetic resonance (CMR). Additionally, the effects of concentric and eccentric LVH on depolarization and repolarization were assessed.

Methods

120 patients with aortic valve disease and 30 healthy volunteers were analysed. As ECG criteria for LVH, we assessed the Sokolow-Lyon voltage/product, Gubner-Ungerleider voltage, Cornell voltage/product, Perugia-score and Romhilt-Estes score.

Results

All ECG criteria demonstrated a significant correlation with LV mass and chamber size. The highest predictive values were achieved by the Romhilt-Estes score 4 points with a sensitivity of 86% and specificity of 81%. There was no difference in all ECG criteria between concentric and eccentric LVH. However, the intrinsicoid deflection (V6 37 ± 1.0 ms vs. 43 ± 1.6 ms, p < 0.05) was shorter in concentric LVH than in eccentric LVH and amplitudes of ST-segment (V5 -0.06 ± 0.01 vs. -0.02 ± 0.01) and T-wave (V5 -0.03 ± 0.04 vs. 0.18 ± 0.05) in the anterolateral leads (p < 0.05) were deeper.

Conclusion

By calibration with CMR, a wide range of predictive values was found for the various ECG criteria for LVH with the most favourable results for the Romhilt-Estes score. As electrocardiographic correlate for concentric LVH as compared with eccentric LVH, a shorter intrinsicoid deflection and a significant ST-segment and T-wave depression in the anterolateral leads was noted.  相似文献   
996.

Introduction  

Disturbed alveolar fibrin turnover is a cardinal feature of severe pneumonia. Clinical studies suggest that natural inhibitors of coagulation exert lung-protective effects via anticoagulant and possibly also anti-inflammatory pathways. Intravenous infusion of the natural anticoagulants increases the risk of bleeding. Local administration may allow for higher treatment dosages and increased local efficacy while at the same time reducing the risk of bleeding. We evaluated the effect of nebulized anticoagulants on pulmonary coagulopathy and inflammation in a rat model of Streptococcus pneumoniae pneumonia.  相似文献   
997.

Introduction

Randomized trials indicate that adjuvant radiotherapy plus tamoxifen decrease the five-year risk of recurrence among ductal carcinoma in situ patients treated with breast-conserving surgery from about 20% to 8%. The aims of this study were to examine the use and impact of these therapies on risk of recurrence among ductal carcinoma in situ patients diagnosed and treated in the community setting.

Methods

We identified 2,995 patients diagnosed with ductal carcinoma in situ between 1990 and 2001 and treated with breast-conserving surgery at three large health plans. Medical charts were reviewed to confirm diagnosis and treatment and to obtain information on subsequent breast cancers. On a subset of patients, slides from the index ductal carcinoma in situ were reviewed for histopathologic features. Cumulative incidence curves were generated and Cox regression was used to examine changes in five-year risk of recurrence across diagnosis years, with and without adjusting for trends in use of adjuvant therapies.

Results

Use of radiotherapy increased from 25.8% in 1990-1991 to 61.3% in 2000-2001; tamoxifen increased from 2.3% to 34.4%. A total of 245 patients had a local recurrence within five years of their index ductal carcinoma in situ. The five-year risk of any local recurrence decreased from 14.3% (95% confidence interval 9.8 to 18.7) for patients diagnosed in 1990-1991 to 7.7% (95% confidence interval 5.5 to 9.9) for patients diagnosed in 1998-1999; invasive recurrence decreased from 7.0% (95% confidence interval 3.8 to 10.3) to 3.1% (95% confidence interval 1.7 to 4.6). In Cox models, the association between diagnosis year and risk of recurrence was modestly attenuated after accounting for use of adjuvant therapy. Between 1990-1991 and 2000-2001, the proportion of patients with tumors with high nuclear grade decreased from 46% to 32% (P = 0.03) and those with involved surgical margins dropped from 15% to 0% (P = 0.03).

Conclusions

The marked increase in the 1990s in the use of adjuvant therapy for ductal carcinoma in situ patients treated with breast-conserving surgery in the community setting only partially explains the 50% decline in risk of recurrence. Changes in pathology factors have likely also contributed to this decline.  相似文献   
998.
999.
Metastases from prostate cancer occur largely in bone through a haematogenous route. Metastatic spread of prostate cancer to the leptomeninges was rarely seen in the past. However, there has been a recent increase in presentations of leptomeningeal spread from prostate cancer in our institutions. Between 2004 and 2006, four patients were diagnosed with metastatic prostate cancer with leptomeningeal metastases in our centres. All four patients had hormone refractory prostate cancer and had previously had chemotherapy. The median survival of these patients was approximately 15 months from the time of hormone refractoriness. The prognosis of leptomeningeal metastasis secondary to metastatic prostate cancer is poor, ranging from 2 to 7 months as seen in our series. New cases of leptomeningeal metastases seen in our series are hypothesized to be secondary to the use of effective modern systemic treatments. A parallel might be drawn with the increased rate of central nervous system metastases in breast cancer since the introduction of effective cytotoxic treatments and more recently targeted therapies. We suggest the clinicians to be aware of the potential change of natural history and pattern of progression in metastatic prostate cancer.  相似文献   
1000.
Immunodominance (ID) of T cell epitopes is a well-documented phenomenon that might have profound significance in the evolution of T cell responses to pathogens, tumors, autoantigens and vaccines. With the intention of developing vaccines composed of several cytotoxic T cell (CTL) epitopes, we injected mice with peptide mixtures containing two to five CTL epitopes and observed clear patterns of ID. In a first case, ID strictly correlated with the competitor activity of the individual peptides for H-2Kd, whereas in a second case, the absence of correlation between ID and competitor activity, binding affinity, half-life of the peptides in serum, induction of proliferation in vitro and the individual immunogenicity of the peptides, suggested to us that ID of co-injected CTL epitopes can be determined both at the peptide level (binding affinity to H-2Kd) and at the T cell level. This hypothesis is supported by our finding that interleukin-12 strongly modulates ID when it is not correlated with MHC binding.  相似文献   
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