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991.
PURPOSE: To examine if excessive in-stent neointimal formation causing a subcritical stenosis may indicate enhanced vascular reactivity in response to injury, thus predicting late cardiovascular events. METHODS: One hundred consecutive patients (64 men; median age 71 years) with high-grade internal carotid artery stenoses (68 asymptomatic, 32 symptomatic) underwent carotid artery stenting (CAS). High-sensitivity C-reactive protein (hs-CRP) was measured before CAS. Patients were monitored with duplex ultrasound for excessive in-stent neointimal formation (flow-compromising lumen diameter reduction >/=50%), critical restenosis (>/=70%), or the occurrence of late major adverse cardiovascular events (MACE) defined as myocardial infarction (MI), stroke, and death occurring later than 30 days poststenting. RESULTS: Over a median 23-month follow-up, excessive neointimal formation was observed in 14 (14%) patients, restenosis in 2 (2%), and 30 late MACE in 25 [25%: 4 MIs, 2 ipsilateral strokes (in the patients with restenosis), 8 contralateral strokes, and 16 cardiovascular deaths]. Cumulative MACE-free survival rates at 6, 12, and 24 months were 92%, 84%, and 77%, respectively. Baseline hs-CRP levels were associated both with neointimal hyperplasia (p=0.024) and MACE (p=0.021). Patients with excessive neointimal formation exhibited a significantly increased adjusted risk for MACE (hazard ratio 3.56, p=0.010). CONCLUSIONS: Excessive in-stent neointimal formation after CAS indicates an increased risk for late MACE, potentially reflecting a state of exaggerated vascular reactivity in response to injury. Inflammation, which is associated both with neointimal hyperplasia and MACE, seems a common characteristic of different vascular pathologies.  相似文献   
992.
993.
OBJECTIVES: The new human herpesvirus type 8 (HHV-8) has been detected in all types of Kaposi's sarcomas, as well as in body-cavity lymphomas and Castleman's disease. Recently, HHV-8 has also been associated with encephalitis in HIV-positive and HIV-negative patients. Interstitial pneumonitis, combined with detection of HHV-8 in non HIV-infected patients, indicates a pathogenetic role of HHV-8 in unexplained lung diseases. We have studied two HIV-infected patients, with otherwise unexplained interstitial pneumonitis for the presence of HHV-8. METHODS: Lung biopsies of both patients were investigated for HHV-8 sequences. A nested PCR method was used for amplification of HHV-8 DNA fragments, and the nature of the amplification products was confirmed by Southern blot hybridization. In addition, we used an in situ hybridization technique and immunohistochemical staining for detection of HHV-8 infected cells. RESULTS: Amplification of HHV-8 DNA fragments was seen with template DNA from lung biopsies of both cases and the appropriate positive controls, but not with negative controls. In situ hybridization and immunohistochemical staining demonstrated HHV-8 infected lymphoid cells and alveolar macrophages in both patients as well. CONCLUSIONS: HHV-8 was found in HIV-infected patients with otherwise unexplained interstitial pneumonitis, but the pathogenic role of HHV-8 in patients with interstitial pneumonia remains unclear.  相似文献   
994.
Thyroid hormone is essential for fetal and neonatal development in particular of the brain, but little is known about regulation of fetal thyroid hormone levels throughout human gestation. The purpose of this study was to clarify developmental trends and interrelationships among T(4), free T(4) (FT4), thyroxine-binding globulin (TBG), TSH, T(3), rT(3), and T(4) sulfate (T4S) levels in cord and fetal blood sera (n = 639, 15-42 wk gestation) and correlate infant levels (23-42 wk gestation) to maternal values (n = 428, 16-45 yr) and those of nonpregnant women (n = 233, 16-46 yr). In cord and fetal serum, T(4), T(3), and TBG levels increase with gestation until term; TSH, FT4, T4S, and rT(3) levels increase and peak in the late second/early third trimester and then decline to term; T(4)/TBG ratios increase until late second trimester and plateau to term. Term cord sera TSH, TBG, and all iodothyronine levels, except T(3), are higher than nonpregnant women. In the third trimester, cord serum FT4, TSH, rT(3), and T4S levels are also higher than corresponding maternal levels, but T(4), T(3), and TBG levels are lower than maternal values. The late second/early third trimester is a critical transition period in fetal thyroid hormone metabolism, which may be interrupted by preterm birth and contribute to postnatal thyroid dysfunction.  相似文献   
995.
Summary Islet cell antigen (ICA) 69 is a newly-recognized islet cell antigen to which autoantibodies have been observed in prediabetic relatives of patients with insulin-dependent-diabetes mellitus (IDDM). Here we extend the earlier analysis of ICA 69 antibodies to patients with recent-onset IDDM and to patients with other immune-mediated diseases. ICA 69 antibodies were determined by Western blot using an affinity purified recombinant fusion protein of ICA 69 and maltose binding protein. ICA 69 antibody quantities were determined as titres using a titration curve of a standard serum as reference. Mean logarithmic ICA 69 antibody titres were 3.4 (±1.4) in 99 patients with acute IDDM compared to 2.8 (±0.9) in 49 healthy blood donors (p<0.001). A higher mean ICA 69 antibody titre of 4.1 (±0.8) was observed in 16 patients with rheumatoid arthritis in comparison to acute IDDM (p<0.01) and healthy control subjects (p<0.001). The percentage of sera with ICA 69 antibody titres above the 2 SD level of normal subjects was 21% in IDDM, 31% in rheumatoid arthritis and 6% in healthy blood donors. None of the patients with autoimmune thyroid disease (n=20), inflammatory bowel disease (n=9) or multiple sclerosis (n=7) had elevated ICA 69 antibodies. In IDDM, presence of ICA 69 antibodies persisted and the titre remained the same over 18 months of follow-up. The relationship of ICA 69 antibodies to islet cell antibodies (ICA) or insulin autoantibodies (IAA) was tested. The production of ICA 69 antibodies was not associated in diabetic patients with the presence of any of the two other autoantibodies. In conclusion, this study describes ICA 69 antibodies in acute IDDM and finds them to be independent of other islet autoantibodies. In addition ICA 69 is a target of humoural autoimmunity not only in IDDM but also in rheumatoid arthritis.Abbreviations IDDM Insulin-dependent diabetes mellitus - ICA islet cell antibodies - IAA insulin autoantibodies - RA rheumatoid arthritis - RF rheumatoid factor - GAD 65 glutamic acid decarboxylase - SMS stiff-man syndrome  相似文献   
996.
997.
998.
Although caffeine is known to stimulate small intestinal water secretion in man, no available studies have examined the effect of coffee on small intestinal fluid transport. We have studied the effect of both coffee and caffeine on jejunal sodium and water transport by the triple lumen intestinal perfusion technique. Both caffeine and coffee solutions had equivalent caffeine concentrations, approximating the caffeine concentration in one cup of coffee. Control and coffee perfusion resulted in net absorption of 0.9 +/- 0.2 and 1.1 +/- 0.3 ml per min per 30 cm, respectively, whereas caffeine perfusion resulted in net water secretion of 2.4 +/- 0.4 ml per min per 30 cm (P less than 0.02). Net sodium absorption was observed with control and coffee solutions with a mean absorption of 190 +/- 32 and 184 +/- 40 muEq per min per 30 cm, respectively. Net sodium secretion of 334 +/- 25 muEq er min per 30 cm was observed during caffeine perfusion (P less than 0.02). We conclude that coffee perfusion has no significant effect on sodium and water transport in the jejunum in spite of the marked secretory effects of caffeine solutions. The results of this study yield further support to the suggestion that the effects of caffeine may not be similar to the effects of caffeine-containing compounds such as coffee.  相似文献   
999.
Identification of low-risk monitor admissions to medical-surgical ICUs   总被引:1,自引:0,他引:1  
D P Wagner  W A Knaus  E A Draper 《Chest》1987,92(3):423-428
A total of 5,790 intensive care unit (ICU) admissions from 13 tertiary care institutions were studied to identify patients who were at such low risk of receiving unique ICU therapies that admission might have been avoided or the length of ICU stay reduced. We used acute severity of disease on admission to the ICU along with the type of disease or surgery to risk stratify individual ICU patients. Among 1,941 patients who only received monitoring services on admission to the ICU, 1,358 (70 percent) were predicted to have less than a 10 percent risk of requiring subsequent active ICU treatment. Only 58 (4.3 percent) of these low-risk patients actually received active treatment. The identification of low-risk patients was equally accurate in estimation and validation data sets. Our methods should allow physicians and hospitals to assess their current ICU utilization and, if appropriate, guide reductions in use.  相似文献   
1000.
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