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81.
Esophageal Involvement in Lymphoma   总被引:1,自引:0,他引:1  
Esophageal involvement by lymphoma in three patients, two with non-Hodgkin's lymphoma and one with Hodgkin's lymphoma are reported. In all three patients, there was discrete involvement of the esophagus not directly contiguous with the stomach. Esophageal involvement by lymphoma either as a primary disease or as manifestation of a disseminated disease is distinctly uncommon.  相似文献   
82.
An outbreak of respiratory illness due to Branhamella catarrhalis occurred in the intermediate care unit of a Veterans Administration hospital and involved patients and staff members. Four patients had pneumonia and four had bronchitis. Infected patients were placed in a cohort separated from noninfected patients and were treated. Pharyngeal culture was used to survey prevalence in staff and all other patients on the unit; three of 18 staff members and two of 19 asymptomatic patients were positive for B. catarrhalis. A case-control study showed that respiratory therapy, steroid use, and location within the unit were significant risk factors for B. catarrhalis infection or colonization. Strains from five patients and two staff members had identical bacterial restriction endonuclease digestion patterns with three different enzymes; these patterns were distinct from those of control strains. This study is the first to document an outbreak of B. catarrhalis infection confirmed with a typing system and thus establishes B. catarrhalis as a nosocomial pathogen.  相似文献   
83.
The reliability of CKMB in cases in which damage of sceletal muscles and myocardium occurred in close sequence is tested in dogs. Results show that in simultaneous damage of heart and muscles, CKMB exceeds the requested ratio of 5 to 8% of total CK, thus proving the myocardial infarction. In cases in which myocardial infarction succeeds a damage of sceletal muscle--e.g. a polytrauma --within distance of hours only, the absolutely high level of CKMB proves the infarction, even below the critical ratio of the total CK.  相似文献   
84.
Restless legs syndrome (RLS) is a common multifactorial disease. Some genetic risk factors have been identified. RLS susceptibility also has been related to iron. We therefore asked whether known iron-related genes are candidates for association with RLS and, vice versa, whether known RLS-associated loci influence iron parameters in serum. RLS/control samples (n=954/1814 in the discovery step, 735/736 in replication 1, and 736/735 in replication 2) were tested for association with SNPs located within 4 Mb intervals surrounding each gene from a list of 111 iron-related genes using a discovery threshold of P=5 × 10−4. Two population cohorts (KORA F3 and F4 with together n=3447) were tested for association of six known RLS loci with iron, ferritin, transferrin, transferrin-saturation, and soluble transferrin receptor. Results were negative. None of the candidate SNPs at the iron-related gene loci was confirmed significantly. An intronic SNP, rs2576036, of KATNAL2 at 18q21.1 was significant in the first (P=0.00085) but not in the second replication step (joint nominal P-value=0.044). Especially, rs1800652 (C282Y) in the HFE gene did not associate with RLS. Moreover, SNPs at the known RLS loci did not significantly affect serum iron parameters in the KORA cohorts. In conclusion, the correlation between RLS and iron parameters in serum may be weaker than assumed. Moreover, in a general power analysis, we show that genetic effects are diluted if they are transmitted via an intermediate trait to an end-phenotype. Sample size formulas are provided for small effect sizes.  相似文献   
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The aim of this study was to assess the side effects and the efficacy of thalidomide alone or in combination with dexamethasone in relapsed multiple myeloma (MM) and to evaluate possible predictive factors for response rate and survival. Twenty-nine pretreated patients were enrolled, including 13 patients with a relapse after high-dose chemotherapy. The median number of relapses was 3 (range: 1–7). Twenty-two patients received thalidomide in combination with dexamethasone and seven patients thalidomide alone. The dosage of thalidomide was 400 mg/day and the dosage of dexamethasone 20 mg/m2 daily for 4 consecutive days every 3 weeks. Cycles of dexamethasone were given until maximal decline of myeloma protein was achieved, whereas therapy with thalidomide was maintained until disease progression. Responses occurred in 62% of patients, including 5 (17%) complete remissions and 13 (45%) partial remissions. The median event-free survival (EFS) was 7.2 months and the median overall survival (OS) 26.1 months. In multivariate analysis, pretreatment serum levels of soluble interleukin-2 receptor (sIL-2R) were a significant prognostic factor for EFS, and those of 2-microglobulin (2M) and sIL-2R for OS. Serum levels of sIL-2R significantly increased after 3 weeks of treatment in 89% of patients, possibly representing lymphocyte activation induced by thalidomide. Two patients died of septic complications within 3 months after starting treatment with thalidomide and dexamethasone and one patient of herpes encephalitis after 26 months of treatment with thalidomide alone. Also, one case of pneumonia and one case of deep venous thrombosis of the lower limb occurred. Other side effects were somnolence, peripheral neuropathy, and bradycardia occurring in 35, 55, 38 and 55% of patients, respectively. The combination of thalidomide and dexamethasone is an effective therapy in heavily pretreated myeloma patients with a high response rate and acceptable toxicities. A powerful predictive factor both for EFS and OS was the pretreatment serum level of sIL-2R.  相似文献   
89.
Anomalously warm sea-surface temperatures (SSTs) are associated with interannual and decadal variability as well as with long-term climate changes indicative of global warming. Such oscillations could precipitate changes in a variety of oceanic processes to affect marine species worldwide. As global temperatures continue to rise, it will be critically important to be able to predict the effects of such changes on species' abundance, distribution, and ecological relationships so as to identify vulnerable populations. Off the coast of British Columbia, warm SSTs have persisted through the last two decades. Based on 16 years of reproductive data collected between 1975 and 2002, we show that the extreme variation in reproductive performance exhibited by tufted puffins (Fratercula cirrhata) was related to changes in SST both within and among seasons. Especially warm SSTs corresponded with drastically decreased growth rates and fledging success of puffin nestlings. Puffins may partially compensate for within-season changes associated with SST by adjusting their breeding phenology, yet our data also suggest that they are highly vulnerable to the effects of climate change at this site and may serve as a valuable indicator of biological change in the North Pacific. Further and prolonged increases in ocean temperature could make Triangle Island, which contains the largest tufted puffin colony in Canada, unsuitable as a breeding site for this species.  相似文献   
90.
A patient with intermittent left bundle branch block and moderate aortic insufficiency, presumably due to rheumatic heart disease, is presented.

At retrograde left heart catheterization, left bundle branch block recurred repeatedly and was always converted to normal conduction and left ventricular hypertrophy by administration of oxygen. Electrocardiograms, intracardiac pressures and indicator-dilution curves for cardiac output were recorded with both types of conduction.

The following hemodynamic alterations consistently accompanied intermittent left bundle branch block:

1. 1. There was a significant fall in the systolic pressures in the left ventricle, central aorta and radial artery, a decreased stroke volume and an increased heart rate. These findings suggest that the force and intensity of left ventricular contraction and, consequently, systolic ejection are significantly decreased with the onset of delayed conduction.
2. 2. A prolonged phase of isometric contraction was the most important alteration in the time relationships of the hemodynamic events of ventricular contraction. This resulted in delay in onset and termination of systolic ejection, with a normal duration of the ejection phase. Isometric relaxation was also prolonged proportionately, but duration of diastole shortened as the cardiac rate increased. Prolonged isometric contraction of the left ventricle is probably responsible for the delayed closure of the aortic valve and paradoxic or fixed splitting of the second heart sound very often seen with left bundle branch block.
  相似文献   
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