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331.
Although pulsed Doppler echocardiography estimates current left ventricular (LV) filling, left atrial (LA) size reflects LV filling and pressure over time. However, the wide normal LA size range may blunt this diagnostic tool. Our objective was to compare the intraindividual atrial area difference (LA--right atrial [RA] area) and absolute LA area in their detection of a LA enlargement with respect to the degree of current LV filling impairment. We examined patients with acute coronary syndromes in sinus rhythm and without valvular disease (n = 154), and age- and gender-matched healthy controls (n=50) with echocardiography, applying pulsed Doppler international recommendations to group the patients according to the LV filling pattern: 0, normal; 1, delayed relaxation; 2, an isolated abnormal mitral pulmonary venous A-wave duration difference; 3, pseudonormal; and 4, restrictive. The LA and RA areas were measured in the 4-chamber view. Control values defined the normal range of: absolute LA area, LA area adjusted for body height, and LA-RA area. These areas indicated a LA enlargement in: (1) controls, 2%, 2%, and 4%, respectively; (2) patients with LV filling graded as normal/mildly impaired (groups 0 and 1), 15%, 17%, and 46%, respectively; moderately impaired (group 2), 26%, 29%, and 52%, respectively; and severely impaired (group 3 and 4), 42%, 38%, and 54%, respectively. Unequally sized atria appear to detect LA enlargement sensitively, especially when Doppler evidence of LV filling pathology is sparse. Clinically, with no obvious current cause for LA enlargement, a diagnosed "atrial size inequality" may still indicate a history of such causes.  相似文献   
332.
OBJECTIVE: To describe mortality, mode of death, risk indicators for death and symptoms of angina pectoris among survivors during 5 years after coronary artery bypass grafting (CABG) among patients with and without a history of diabetes mellitus. METHODS: All patients in western Sweden who underwent CABG without concomitant valve surgery and who had no previous CABG between June 1988 and June 1991 were entered prospectively in this study. After 5 years, information on deaths that had occurred was obtained for the analysis. RESULTS: In all, 1998 patients were included in the analysis; 242 (12%) had a history of diabetes. Among the non-diabetic patients, 5-year mortality was 12.5%; the corresponding relative risk for diabetic patients was 2.1 (95% confidence interval 1.6 to 2.9). A history of diabetes was an independent risk indicator of death; there was no significant interaction between any other risk indicator and diabetes. Independent risk indicators for death among diabetic patients were: current smoking, renal dysfunction and left ventricular ejection fraction < 0.40. Compared with non-diabetic patients, those with diabetes more frequently died in hospital, died a cardiac death, or had death associated with the development of acute myocardial infarction and with symptoms of congestive heart failure. Among survivors, diabetic patients tended to have more angina pectoris 5 years after CABG than did those without diabetes. CONCLUSION: During a period of 5 years after CABG, diabetic patients had a mortality twice that of non-diabetic patients. The increased risk included death in hospital, cardiac death and death associated with development of acute myocardial infarction and with symptoms of congestive heart failure.  相似文献   
333.
The importance of banded chromosome analyses in predicting long-term outcome in acute lymphoblastic leukemia (ALL) was evaluated in this follow-up study of 329 patients from the Third International Workshop on Chromosomes in Leukemia. Patients were divided into ten groups according to pretreatment karyotype: no abnormalities, one of the following structural abnormalities [the Philadelphia chromosome, translocations involving 8q24,t(4;11), 14q+, 6q-] or, in the remaining cases, modal number [less than 46, 46, 47 to 50, greater than 50]. Achievement and duration of complete remission (CR) and survival differed among chromosome groups (P less than .0001). Karyotype was an independent prognostic factor for duration of first CR and survival, even when age, initial leukocyte count (WBC), French-American-British (FAB) type, and immunologic phenotype were considered. Among adults, prolonged remission and survival were uncommon in all chromosome groups. Only in the normal karyotype group was median survival even two years. Among children, striking differences in long-term remission and survival were seen depending upon karyotype. Children in the greater than 50 group did best, with 70% remaining in first CR for a median duration in excess of five years. Children in the 47-50, 6q-, and normal karyotype groups also had prolonged survivals. In contrast, certain translocations [t(9;22)(q34;q11), t(4;11)(q21;q14-23), t(8;14)(q24;q32)] identified children who had short survivals, even in the presence of favorable prognostic factors including a low WBC, L1 morphology, and non-T, non-B immunologic phenotype. We conclude that chromosome analysis is required at diagnosis in patients with ALL, and that children with these specific translocations should be managed as having high-risk ALL.  相似文献   
334.
The relation between dyspnoea of presumed cardiac origin and disturbed left ventricular systolic function was studied in a group of 67 year old men from the general population of Gothenburg, Sweden. Forty two men with cardiac dyspnoea were identified and 45 controls were randomly selected from a screened cohort of 644 men. Dyspnoea was graded according to the World Health Organisation standard, and M mode echocardiography, carotid pulse tracing, an apex cardiogram, and phonocardiography were used to evaluate the grade of dyspnoea and its relation to systolic time intervals, left ventricular ejection indices, and wall stress. The dyspnoea grade was significantly related to the left ventricular end systolic dimension, to septal and posterior wall fractional thickening, and to ejection indices such as fractional shortening. The dyspnoea grade was also significantly correlated with the ratio of end systolic wall stress to end systolic volume index. There was a close relation between end systolic wall stress and mean velocity of circumferential fibre shortening adjusted for heart rate. This relation did not clearly show reduced inotropy in the dyspnoeic men. There was no relation between the degree of dyspnoea and the systolic time intervals. Among the systolic variables obtained by echocardiography the only abnormal finding in mild to moderate dyspnoea was an increased end systolic dimension. The grade of cardiac dyspnoea seemed to be related to the degree of systolic left ventricular dysfunction, which was considerably impaired in severe dyspnoea. In population studies left ventricular end systolic dimension and fractional shortening may provide sufficient information on systolic function without the need to assess variables that are independent of load.  相似文献   
335.
336.
The human granulocyte-colony stimulating factor gene (G-CSF) is localized at 17q11.2-q21, the region of one of the breakpoints in the 15;17 chromosome translocation specific for acute promyelocytic leukemia (APL). As G-CSF induces differentiation and loss of tumorigenicity in myeloid leukemic cells or cell lines, it was possible that the translocation in APL involved the DNA of the G-CSF coding region or its regulatory region. In situ hybridization to chromosomes with the t(15;17) from patients with the APL translocation using a G- CSF cDNA clone revealed that the coding region of this gene is proximal to the t(15;17) breakpoint on chromosome 17. Southern analysis of DNA from patients with the APL translocation showed no differences in hybridization between normal and leukemic cells. These results indicate that the G-CSF coding sequence is not disrupted by the chromosomal rearrangement characteristic of APL.  相似文献   
337.
J T Hartford 《Geriatrics》1979,34(6):83-93
Aging has a direct effect on drug absorption, distribution, and elimination. With aging, there is an alteration in the neurotransmitters whereby dopaminergic and catecholaminergic systems are relatively depleted of monoamines while acetylcholine is largely unaffected. Pharmacotherapy in the elderly requires an understanding of the physiologic effects of medications. Dosage generally should be lower for the elderly patient on the basis of a milligram per kilogram of body weight, but determining the appropriate dosage required more than allowing for "smaller body mass" or "less body water." Because of lengthened half-life and slowed distribution of medications, it is necessary to start with very low dosages and observe the patient for relatively longer periods of time before giving another dose, increasing the medication, or adding another drug.  相似文献   
338.
Mutations of FLNA, an X-linked gene that encodes the cytoskeletal protein filamin A, cause diverse and distinct phenotypes including periventricular nodular heterotopia and otopalatodigital spectrum disorders (OPDS). Craniofacial abnormalities associated with OPDS include supraorbital hyperostosis, down-slanting palpebral fissures and micrognathia; craniosynostosis was previously described in association with FLNA mutations in two individual case reports. Here we present four further OPDS subjects who have pathological FLNA variants and craniosynostosis, supporting a causal link. Together with the previously reported patients, frontometaphyseal dysplasia was the most common clinical diagnosis (four of six cases overall); five patients had multiple suture synostosis with the sagittal suture being the most frequently involved (also five patients). No genotype–phenotype correlation was evident in the distribution of FLNA mutations. This report highlights the need to consider a filaminopathy in the differential diagnosis of craniosynostosis, especially in the presence of atypical cranial or skeletal features.  相似文献   
339.
340.
目的:报告1例继发于前额粘液囊肿的左眼眶脓肿患者。方法:病例报告。结果:1例30岁马来西亚妇女,表现为左眼疼痛、肿胀3d,伴视力下降和上眼睑下垂。CT报告左额窦粘液囊肿蔓延至左眶内。手术引流治疗,视力和上眼睑下垂很快改善。结论:眼眶脓肿可继发于前额粘液囊肿,而且患者可无鼻旁窦既往病史。  相似文献   
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