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991.

Background

Tumor lysis syndrome (TLS) is a life-threatening emergency disorder, caused by an abrupt release of intracellular metabolites after tumor cell death. It is characterized by a series of metabolic manifestations, especially hyperuricemia, hyperkalemia, hyperphosphatemia and hypocalcemia. The aim of this study was to evaluate and characterize the incidence of tumor lysis syndrome among pediatric oncology patients before and after treatment.

Methods

Hospital based prospective cohort study was conducted for 6 months on 61 newly diagnosed pediatric oncology patients. Socio-demographic data was collected by interview administered questionnaire. Patients were followed and the physical diagnosis, imaging and laboratory results were interpreted by senior physicians. Data was entered to and analyzed by SPSS version 23.

Results

Among 61 pediatric oncology patients 39(63.9%) were males. The mean (±SD) age of the pediatric patients was 6.39 (±?3.67) years ranging from 2 months to 14 years. 29.5% of patients were found to have TLS. There were 11.5% and 18.0% of laboratory TLS (LTLS) and clinical TLS (CTLS) cases respectively. There were72.2% spontaneous and 27.8% treatment induced TLS cases with 23% and 21.3% cases of hyperuricemia and 4.9% and 6.6% cases of hyperkalemia incidence before and after treatment respectively. Only two patients died, in the study period, due to TLS.

Conclusion

There was high incidence of TLS irrespective of socio-demographic variation among study participants, suggesting that children with cancer are at risk of developing TLS. As TLS is a life-threatening complication of malignancies, early identification of patients at risk and reducing morbidity and mortality is crucially important.
  相似文献   
992.
Magic-angle spinning (MAS) solid-state NMR (SSNMR) techniques have emerged in recent years for solving complete structures of uniformly labeled proteins lacking macroscopic order. Strategies used thus far have relied primarily on semiquantitative distance restraints, analogous to the nuclear Overhauser effect (NOE) routinely used in solution NMR. Here, we present a complementary approach for using relative orientations of molecular fragments, determined from dipolar line shapes. Whereas SSNMR distance restraints typically have an uncertainty of approximately 1 A, the tensor-based experiments report on relative vector (pseudobond) angles with precision of a few degrees. By using 3D techniques of this type, vector angle (VEAN) restraints were determined for the majority of the 56-residue B1 immunoglobulin binding domain of protein G [protein GB1 (a total of 47 HN-HN, 49 HN-HC, and 12 HA-HB restraints)]. By using distance restraints alone in the structure calculations, the overall backbone root-mean-square deviation (bbRMSD) was 1.01 +/- 0.13 A (1.52 +/- 0.12 A for all heavy atoms), which improved to 0.49 +/- 0.05 A (1.19 +/- 0.07 A) on the addition of empirical chemical shift [torsion angle likelihood obtained from shift and sequence similarity (TALOS)] restraints. VEAN restraints further improved the ensemble to 0.31 +/- 0.06 A bbRMSD (1.06 +/- 0.07 A); relative to the structure with distances alone, most of the improvement remained (bbRMSD 0.64 +/- 0.09 A; 1.29 +/- 0.07 A) when TALOS restraints were removed before refinement. These results represent significant progress toward atomic-resolution protein structure determination by SSNMR, capabilities that can be applied to a large range of membrane proteins and fibrils, which are often not amenable to solution NMR or x-ray crystallography.  相似文献   
993.
Adir Y  Shupak A  Laor A  Weiler-Ravell D 《Chest》2005,128(1):224-228
BACKGROUND: Normal spirometry is required for medical clearance of professional divers in many countries. Divers frequently have unusually large lung volumes associated with a low ratio of FEV(1) to FVC (FEV(1)%), suggestive of obstructive airways disease. We retrospectively analyzed the records of divers in the Israeli Navy with a low FEV(1)% who fulfilled the criteria for large lungs, to determine whether this might be the effect of training or natural selection. We also investigated changes in pulmonary function in relation to diving experience. METHODS: A total of 171 divers with FEV(1)% < 80% on simple spirometry were evaluated. We conducted a retrospective analysis of lung function data for those subjects who met the criteria for large lungs. RESULTS: One hundred nine of 171 divers with low FEV(1)% met the criteria for large lungs and were included in the study. Their average age was 25 years (range, 18 to 44 years), and their mean diving experience was 7 years (range, 0 to 26 years). No difference was found in FVC values between experienced and inexperienced divers. The mean forced expiratory flow at 50% of vital capacity was significantly reduced in the most experienced group compared with the novice or less experienced divers. No difference was found in the diffusing capacity of the lung for carbon monoxide between experienced and inexperienced divers. CONCLUSIONS: We suggest that large lungs may represent part of the natural selection for diving, rather than a training effect. Prolonged diving experience may result in the development of small airways disease.  相似文献   
994.
The ability of an independently developed QRS point score to estimate the size of infarcts predominantly within the anterior third of the left ventricle was evaluated by quantitative pathologic-electrocardiographic correlation. The study was limited to 21 patients with a single infarct documented by postmortem examination, for whom an appropriately timed standard 12 lead electrocardiogram was available that did not exhibit signs of left or right ventricular hypertrophy, left or right bundle branch block or anterior or posterior fascicular block. At necropsy the heart was cut into five to seven slices. The location and size of the infarct was quantitated by computer-assisted planimetry of the slices.The electrocardiogram of 19 (90 percent) of the patients exhibited either a Q wave or an R wave of no more than 20 ms in lead V2. The infarct in the two patients without this electrocardiographic finding was small, occupying 2 and 3 percent of the left ventricle, respectively. The percent infarction of the left ventricle correlated with the QRS point score (r = 0.80). Thus in patients without complicating factors in the electrocardiogram and with a single infarct, the electrocardiogram provides a marker for infarction in the anterior third of the left ventricle and permits estimation of infarct size.  相似文献   
995.
OBJECTIVE: To compare maximum oxygen uptake and anaerobic threshold in patients with fibromyalgia (FM) and healthy sedentary controls matched by sex, age, weight, and body mass index. METHODS: Fifty women with FM aged 18-60 years and 50 healthy sedentary controls were studied. All were submitted to a maximum treadmill incremental test. Expired gas, ventilatory anaerobic threshold, and maximum oxygen uptake (VO2max) were evaluated. The influence of FM on quality of life was evaluated by questionnaires: the Fibromyalgia Impact Questionnaire and the Medical Outcomes Study Short-Form (SF-36). RESULTS: In patients with FM, the anaerobic threshold and peak oxygen uptake were significantly reduced. Maximum heartbeat rate was significantly lower in FM, indicating submaximum effort. Linear regression data showed a correlation between peak VO2 and the "Role-physical" domain of the SF-36. No such correlations were noted with anaerobic threshold. CONCLUSION: These results confirm the hypothesis of lower physical fitness in patients with FM. Considering that patients with FM do not achieve a maximum effort, ventilatory anaerobic threshold should be considered as a better fitness index than VO2max.  相似文献   
996.
The aim of this work was to specify the timecourse of response to interferon (IFN) of hepatitis Gvirus (HGV) and hepatitis C virus (HCV) in coinfectedindividuals. A group of 33 patients, undergoing 12 months of IFN therapy for chronic hepatitis C,was screened for the presence of both HGV and HCV RNAsto select seven coinfected patients. Spontaneousrecovery from HGV infection was excluded through the detection of antibodies to the envelope-2protein of HGV and HCV isolates were genotyped. Withinthree months of treatment, we found that HGV RNA wastransiently cleared in 6/7 patients, but the rate of long-term favorable response was very low(1/7). In addition, considering the same individualsseparately, it was shown that HGV and HCV responded toIFN with different kinetics in 5/7 patients. Takentogether, these results underscore the importance of thevirological basis of the resistance to IFNtreatment.  相似文献   
997.
OBJECTIVES: This study was designed to assess the incremental prognostic value of adenosine stress myocardial perfusion single-photon emission computed tomography (MPS) in women versus men, and to explore the prognostic impact of diabetes mellitus. BACKGROUND: Limited data are available regarding the incremental value of adenosine stress MPS for the prediction of cardiac death in women versus men and the impact of diabetes mellitus on post-adenosine MPS outcomes.Of 6,173 consecutive patients who underwent rest thallium-201/adenosine technetium-99m sestamibi MPS, 254 (4.1%) were lost to follow-up, and 586 with early revascularization < or = 60 days after MPS were censored, leaving 2,656 women and 2,677 men. RESULTS: Women had significantly smaller adenosine stress, rest, and reversible defects than men. During 27.0 +/- 8.8 month follow-up, cardiac death rates were lower in women than men (2.0%/year vs. 2.7%/year, respectively, p < 0.05). Before and after risk adjustment, cardiac death risk increased significantly in both men and women as a function of MPS results. Multivariable models revealed that MPS results provided incremental prognostic value over pre-scan data for the prediction of cardiac death in both genders. Also, while comparative unadjusted rates of early (< or =60 days post-test) coronary angiography (17% vs. 23%) and revascularization (8% vs. 12%) were significantly lower in women (p < 0.05), after adjusting for MPS, these rates were similar in men and women. Importantly, diabetic women had a significantly greater risk of cardiac death compared with other patients. Also, after risk adjustment, patients with insulin-dependent diabetes mellitus (IDDM) had higher risk of cardiac death for any MPS result than patients with non-insulin-dependent diabetes mellitus. CONCLUSION: The findings suggest that adenosine MPS has comparable incremental value for prediction of cardiac death in women and men and that MPS is appropriately influencing subsequent invasive management decisions in both genders. Diabetic women and patients with IDDM appear to have greater risk of cardiac death than other patients for any MPS result.  相似文献   
998.
The Sotalol-Amiodarone Fibrillation Efficacy Trial (SAFE-T) is a randomized, double-blind, multicenter, placebo-controlled trial in which the effects of sotalol and amiodarone in maintaining stability of sinus rhythm are being examined in patients with persistent atrial fibrillation at 20 Veterans Affairs medical centers. The time to the occurrence of atrial fibrillation or flutter in patients with atrial fibrillation converted to sinus rhythm is the primary outcome measure, with a number of parameters as secondary end points. SAFE-T had randomized 665 patients when enrollment terminated on October 31, 2001. Follow-up of patients continued until October 31, 2002, for a maximum period of 54 months and a minimum period of 12 months for all patients.  相似文献   
999.
1000.
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