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31.
OBJECTIVE: We investigated the effects of thyroxine (T4) therapy on the cardiac function in subclinical hypothyroidism (SHT) by using the index of myocardial performance (IMP) and the conventional echocardiographic parameters. METHODS: Forty-five SHT patients (F/M:38/7, age 39.9+/-7.9) and 29 healthy subjects (F/M:25/4, age 38.3+/-8.6) were studied. Patients were randomly assigned, in a double-blind manner to receive T4 therapy (group I) or a placebo (group II) and for a period of up to 12 months, were followed up using thyroid function tests and both conventional and Doppler echocardiographic measurements. RESULTS: At the baseline, the SHT patients has a significantly higher isovolumic relaxation time (IRT) (98.3+/-23.7 vs. 81.7+/-14.7<0.01), IMP (0.52+/-0.06 vs. 0.42+/-0.05; P<0.001), A max (late mitral peak velocity) (83.4+/-12.6 vs. 74.3+/-13.5; P<0.01) and significantly lower (early mitral peak velocity) Emax/Amax ratio (1.19+/-0.18 vs. 1.34+/-0.17; P<0.01) than the individuals in the control group. In group I, the thyroid hormone profile became normalized after 1 year of L-T4 therapy, but there was no significant change in the left ventricular (LV) morphology or systolic function. After 1 year of follow-up, group I showed a significant reduction of MPI (0.53+/-0.05 vs. 0.42+/-0.07; P<0.001), Amax (84.2+/-13.7 vs. 74.5+/-11; P<0.001) and IRT (98.6+/-23.7 vs. 82.9+/- 23.3; P<0.001) along with a normalization of the E/A ratio (1.17+/-0.16 vs. 1.33+/-0.19; P<0.001). Conversely, no change was observed in group II. CONCLUSIONS: An impairment of left ventricular diastolic function, which may be reversible with T4 therapy, was observed in the SHT patients, and IMP may be useful in the evaluation of LV myocardial dysfunction in these patients.  相似文献   
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The prevalence of metallo-beta-lactamases (MBLs) produced by isolates of Pseudomonas aeruginosa and Acinetobacter baumannii and the activities of various antmicrobial combinations against MBL producer strains were investigated. During the period from June 2003 till July 2004, 120 P. aeruginosa and 9 A. baumannii nonduplicate isolates were obtained from burn wounds. Forty strains (37 P. aeruginosa, 3 A. baumannii) were selected because of resistance to carbapenems. Screening for MBL production was performed in the latter isolates by the combined disk method which depends on comparing the zones given by disks containing imipenem with and without ethylenediaminetetraacetic acid (EDTA). Of imipenem resistant P. aeruginosa strains, 21 and 1 of A. baumannii were found metallo-beta-lactamase producers. Disk approximation studies were then performed to test for in vitro activities of various antimicrobial combinations. For a total of 21 P. aeruginosa strains, synergy was demonstrated predominantly by ciprofloxacin in combination with ceftazidime and imipenem, by ofloxacin in combination with astreonam. Against MBL producer A. baumannii strain, synergy was detected only with imipenem-ofloxacin combination. None of the combinations were antagonistic. These results suggest that MBL producing P. aeruginosa and A. baumanni strains have been introduced into burn centers, and to prevent the further spread of MBL producers, it is essential for carbapenem resistant isolates to be screened for MBLs.  相似文献   
34.
We investigated animal and human anthrax cases during a 13-year period in eastern Turkey. From 1992 to 2004, a total of 464 animal and 503 human anthrax cases were detected. Most cases occurred in summer. Anthrax remains a health problem in eastern Turkey, and preventive measures should be taken.  相似文献   
35.
Nitric oxide (NO) is an important messenger molecule with a wide range of actions in virtually all cell systems and organs. In kidneys it participates in glomerular and medullary hemodynamics, tubuloglomerular feed-back, renin secretion, and extracellular fluid balance. Although the role of NO in regulating renal function in adults is well-established, it has recently been suggested that NO has a more critical role in maintaining basal renal blood flow and glomerular filtration rate (GFR) in the developing kidney. NO is rapidly metabolized to the stable end products nitrite and nitrate, which are more slowly excreted into the urine. Thus these metabolites can be recommended as useful markers of endogenous NO synthase activity, despite limited data about age-related changes in in-vivo NO production. The aims of this study were to determine age-related normal reference values of serum and urinary NO metabolites and to assess the probable relationship between these metabolites and the GFR. Normal levels of NO end products in blood and urine of 296 healthy children (117 female, 179 male) between the ages of 0 and 16 were investigated, as was whether these values change with age. Serum and urinary nitrate levels did not differ according to sex. Serum nitrate levels are higher in younger children, especially in the newborn period, and decrease with age. Nitrate levels in urine are higher in younger children with a peak in infancy (1 month to 1 year) and decrease with age. It was demonstrated that this decrease in serum and urinary nitrate levels with age parallels the increase in GFR. In conclusion, urinary NO products may be an indirect marker of serum NO levels and NO might have an important regulatory function both in the maintenance of renal function and in the maturation of the developing kidneys.  相似文献   
36.
Non-ketotic hyperglycinaemia is an autosomal recessive disorder of glycine metabolism caused by a defect in the glycine cleavage system. Affected neonates present with lethargy, feeding difficulty, hypotonia, apnoea, poorly controlled convulsions and coma. Four cases are reported, three of whom died in the neonatal period. The fourth case was treated with dextromethorphan and sodium benzoate. He survived with neurodevelopmental delay but is now almost seizure-free.  相似文献   
37.
We followed up a pregnant woman with Addison's disease diagnosed before conception. She presented with hyperemesis gravidarum. Throughout pregnancy, she received prednisone and the basic disease did not deteriorate during pregnancy. She was delivered by caesarean section due to breech presentation. The fetal prognosis was good.  相似文献   
38.
AIM: Cold induced arteriolar constriction in patients with vasospastic Raynaud's syndrome (VRS) produces temporary digital ischaemia. The aim of this study was to ascertain whether 99mTc sestamibi scintigraphy is useful in the diagnosis and the monitoring of treatment in VRS. METHODS: Fifteen patients with VRS and 20 matched normal controls underwent examination. Twelve patients with VRS received therapy. For each patient, one hand was immersed in iced water for 30s while the other hand served as a control. Ten minutes after cooling, 99mTc sestamibi was injected and imaging was performed 60min later. The per cent decrease of the perfusion (%DP) was calculated by semiquantitative analysis to determine the severity of hypoperfusion. RESULTS: In all patients with VRS, moderate or marked hypoperfusion were seen in 99mTc sestamibi images after exposure to the iced water, while there was minimal or mild hypoperfusion in the control groups. Values for %DP were 46.86 +/- 19.04 and 7.85 +/- 4.53 for the VRS group and normal subjects, respectively. The difference between both groups was statistically significant (P = 0.0000). In 12 treated patients with VRS, pre-treatment and post-treatment %DP values were 51.16 +/- 18.42 and 33.58 +/- 17.83, respectively, and a significant difference was seen between both values (P = 0.001). However, there was still a statistically significant difference between control subjects and post-therapy values (7.85 +/- 4.53 vs. 33.58 +/- 17.83, P = 0.0000). The +/- 95% confidence interval of DP for control subjects was 5.7-10% (chi-squared, P = 0.000). When a DP of 10% was used as a cut-off point, sensitivity, specificity and diagnostic accuracy were 100%, 70% and 83%, respectively, for the 99mTc sestamibi scan. There was also a strong correlation between %DP and the duration of the disease (r = 0.80, P = 0.0003). CONCLUSION: The results of this study indicate that a 99mTc sestamibi scan is a valuable imaging method for the determination of digital ischaemia in vasospastic Raynaud's syndrome, and may play a role in evaluating the response to therapy.  相似文献   
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OBJECTIVE: To determine if there is national variation in regimens of upper urinary tract surveillance in patients with primary bladder cancer. METHODS: A questionnaire was sent to 470 consultant urologists from a British Association of Urological Surgeons list in the UK; 301 anonymous replies were received. Two replies were incomplete and therefore the results of 299 questionnaires (64%) were analysed. RESULTS: Of the 299 surgeons, 19 (6%) use no form of upper urinary tract surveillance; 162 (54%) use surveillance in selected patients, i.e. those with carcinoma in situ (47%), multiple bladder tumours at first presentation (39%) and after cystectomy (70%), and 118 (39%) use upper tract surveillance on all patients with a history of bladder cancer. The median (range) screening interval was 24 (12-60) months and surveillance continued for a median of 10 (2 to indefinite) years, continuing for an indefinite period in 33%. CONCLUSIONS: Most urologists use upper tract surveillance in patients with bladder cancer but there is wide variation in the duration and interval for which it continues, and in the type of patient selected for surveillance. Some patients at high risk of upper tract tumour are not being screened. Asymptomatic upper tract tumours may not be diagnosed because the intervals between surveillance are too long, and the duration for which it continues inadequate. There is a need for multidisciplinary national guidelines to reduce variation in practice.  相似文献   
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