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91.
There is a little information in literature about circulating asymmetric dimethylarginine (ADMA) concentrations in polycystic ovary syndrome (PCOS) and the results reported are discrepant. In this study, therefore, we aimed (1) to determine the circulating ADMA concentrations in 44 women with PCOS and 22 age- and BMI-matched healthy controls, (2) to evaluate its correlations with insulin resistance, gonadotrophins, and androgen secretion, and (3) to compare effects of metformin and ethinyl estradiol-cyproterone acetate (EE/CPA) treatments on circulating ADMA concentrations. In conclusion, our data indicate that circulating ADMA concentrations in non-obese, non-hypertensive and young women with PCOS are significantly higher than healthy controls and they improved by a 3-month course of metformin and oral contraceptive treatments.  相似文献   
92.
OBJECTIVE: Monitoring of the dorsal sural sensory nerve action potential (SNAP) is a sensitive method for detection of peripheral neuropathies. We tried to determine the normal dorsal sural nerve conduction values of the childhood population and assessed the clinical utility of this method in diabetic children who have no clinical sign of peripheral neuropathy. METHODS: In the study, 36 healthy and 27 diabetic children were included. In all subjects peripheral motor and sensory nerve studies were performed on the upper and lower limbs including dorsal sural nerve conduction studies. RESULTS: The dorsal sural SNAP mean amplitude was 8.24+/-3.08 microV, mean latency was 2.47+/-0.48 ms, mean sensory conduction velocity was 41.63+/-5.43 m/s in healthy children. Dorsal sural SNAPs were absent bilaterally in one diabetic patient. In the other 26 diabetic patients, the mean dorsal sural nerve distal latency was longer (2.93+/-0.63 ms, P = 0.004), mean SCV was slower than in healthy subjects (36.68+/-7.66 m/s, P = 0.005). However, dorsal sural nerve amplitude was not different between the groups. A dorsal sural nerve latency of more than 2.9 ms had a sensitivity of 50% and a specificity of 75%. A dorsal sural nerve velocity of less than 36 m/s had a sensitivity of 54% and a specificity of 92%. CONCLUSIONS: We designated the reference values of the dorsal sural nerve in healthy children. In addition, our findings suggest that dorsal sural nerve conduction studies may have value to determine neuropathy in the early stages in children with diabetes. SIGNIFICANCE: The dorsal sural nerve conduction studies in diabetic children may have value to determine the neuropathy in its early stages.  相似文献   
93.
Introduction Diffusion-weighted imaging (DWI) is usually performed before injection of intravenous paramagnetic contrast medium. Occasionally, it may be necessary to perform or to repeat DWI after such administration. Our purpose was to evaluate the effect of intravenous gadodiamide (Gd [DTPA-BMA]) on DWI.Methods DWI was performed on 88 brain lesions immediately before, immediately after, and 5–10 min following the end of 0.1 mmol/kg Gd [DTPA-BMA] administration. Signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of the lesions, and the SNRs of normal brain tissue were calculated on b=0 s/mm2 and b=1,000 s/mm2 DW images. Apparent diffusion coefficient (ADC) values of the lesions were measured on ADC maps. A paired t-test was used to determine the significance of differences between the values before and after administration of contrast medium.Results The lesions consisted of 23 intraaxial and 11 extraaxial masses, 19 ischemic strokes, 15 intracranial hemorrhages and 20 demyelinating lesions. Images before and after contrast administration were not significantly different regarding SNRs and CNRs on DWI. This statement was also true for strongly enhanced lesions. However, ADC values significantly decreased after contrast medium injection on early post-contrast DWI in normal brain tissue (1%, P<0.049) and (3%, P<0.008) in lesions. By contrast, on late images, ADC values were normalized.Conclusion Contrast medium injection had significant and time-dependent effects on ADC values. Therefore, only pre-contrast and late DW images should be used in quantitative ADC studies.  相似文献   
94.
BACKGROUND: Diagnosis of tuberculous pleuritis is difficult because of its nonspecific clinical presentation and decreased efficiency of traditional diagnostic methods. We investigated the use of procalcitonin (PCT) concentration in tuberculous pleuritis diagnosis. METHODS: A prospective clinical study was performed with two different patient groups. A total of 28 patients were included: 18 with tuberculosis and 10 with nontuberculous pleurisy. Serum and pleural fluid PCT concentrations were evaluated before treatment. RESULTS: Serum and pleural fluid PCT concentrations were statistically different between tuberculous and nontuberculous pleurisy groups (P = 0.012 and P = 0.004, respectively), even though they were not elevated in relation to the cut-off level of 0.5 ng/mL. A positive and significant correlation was detected between serum and pleural fluid PCT levels (r = 0.49, P = 0.008). Diagnostic specificity and sensitivity values for serum and pleural fluid PCT in discriminating tuberculous from nontuberculous pleurisy were 80% and 72.2%, and 90% and 66.7% at the 0.081 and 0.113 ng/mL cut-off values, respectively. CONCLUSION: Relative to the current cut-off level of 0.5 ng/mL, PCT concentration is not a useful parameter for the diagnosis of tuberculous pleurisy. Because there were PCT levels in patients with tuberculous pleurisy that were below the current cut-off level but were significantly different from those of the nontuberculous group, the use of PCT should be further investigated.  相似文献   
95.
Coronary artery disease (CAD) is believed to be the single leading cause of death in both men and women in the world. Smoking is the most important risk factor for CAD. Smoking increases platelet aggregation and thrombus formation. CD40 ligand (CD40L) is a transmembrane glycoprotein derived from activated platelets. It participates in thrombus formation during the acute phase of acute myocardial infarction (MI). Elevation of CD40L identifies the patients who are at highest risk for cardiac events and who are likely to benefit from treatment with the glycoprotein IIb/IIIa (GPIIb/IIIa) receptor antagonists. The purpose of this study was to evaluate levels of CD40L in smokers with acute MI. Fifty-seven patients with acute MI were enrolled in this study. Thirty-one smokers were compared with 26 non-smokers. Soluble CD40L level in the plasma was determined by a standard enzyme-linked immunosorbent assay. Circulating levels of CD40L were higher in the smokers’ group. Smokers with acute MI may have increased risk for thrombotic complications during acute MI, and optimal antiaggregant therapy should be administered.  相似文献   
96.
97.
Two-dimensional color Doppler tissue imaging (CDTI) has so far been used, in general, to evaluate ventricular function. This study examined if the left atrial appendage tissue velocity could reproducibly be measured with CDTI and if they have any predictive value for left atrial appendage (LAA) function and former thromboembolism. Thirty-six patients (24 women, 12 men; mean age 45 +/- 12 years; 18 AF; 11 former thromboembolic stroke) with mitral stenosis undergoing transesophageal echocardiography were examined with CDTI. Peak systolic tissue velocity (m/sec, peak systolic velocity [PSV]) was measured at the tip of the LAA in the basal short-axis view. LAA flow emptying (LAAEV) and filling (LAAFV) velocities (m/sec) were also recorded 1 cm immediately below the orifice of the appendage. Interobserver and intraobserver variabilities were determined for the PSV. LAA ejection fraction was measured by Simpson's method. Mitral regurgitation, AF, transmitral mean gradient, left ventricular ejection fraction, mitral valve area, and left atrial diameter were used as a covariant for adjustment. The intraobserver and interobserver correlation coefficients for the PSV using CDTI was 0.64 and 0.60, respectively (bothP = 0.01). LAAEV(0.29 +/- 0.09 vs 0.19 +/- 0.04, P = 0.001)and LAA ejection fraction(44 +/- 12 vs 29 +/- 14, P = 0.004)were found to be significantly decreased in the patients with decreased PSV (<0.05 m/sec), even after adjustment. The decreased PSV was positively correlated with the low LAAEV (<0.25 m/sec) and history of thromboembolism (r = 0.59, r = 0.38, respectively), and remained a significant determinant of the low LAAEV (OR 50.03, CI 1.46-1738.11,P = 0.02), but not of history of thromboembolism (OR 4.29, CI 0.52-35.01,P = 0.08) after adjustment. In conclusion, these results suggest that CDTI provides a reproducible method for quantification of contraction at the tip of the LAA. Decreased PSV may be predictive of poor LAA function.  相似文献   
98.
CONTEXT & OBJECTIVE: The Ecuadorian GH receptor deficiency (GHRD)/Laron syndrome population is the only large cohort with a single GHR mutation (E180 splice), permitting identification of numerous carrier and noncarrier first-degree relatives, to ascertain effects of heterozygosity on GH-dependent IGF-I and IGFBP-3 concentrations and on growth. DESIGN: First-degree relatives (n=212) of GHRD patients had specimens taken for IGF-I, IGFBP-3, and GHR genotyping. Normal statured (n=40) and short statured (n=40) unrelated controls had measurement of IGF-I, IGFBP-3, and stature. RESULTS: There were no significant differences between heterozygous and homozygous normal relatives in IGF-I or IGFBP-3 standard deviation scores (SDS). Heterozygous relatives had lower mean height SDS than did homozygous normals, but with extensive overlap between genotype groups in both child and adult relatives. Height SDS in general did not relate to IGF-I or IGFBP-3 concentrations. CONCLUSIONS: GH-dependent IGF-I and IGFBP-3 secretion is not affected by heterozygosity for the E180 splice mutation that causes GHRD/Laron syndrome in the Ecuadorian population. Heterozygosity is associated with reduction in mean statural SDS, but this is not sufficient to be clinically important and not mediated through measurable differences in circulating IGF-I or IGFBP-3 related to genotype.  相似文献   
99.
Osteoid osteoma is one of the unusual causes of musculosceletal pain. A case of a 21-year-old man who had low back and hip pain radiating to the posterior thigh for 3 years is presented. Pain was worse at night but reduced with the use of nonsteroidal anti-inflammatory drugs. Straight leg raising test was negative. Patrick–Fabere and sacroiliac compression tests were positive on the right. Neurological examination was normal. Lumbar spinal and pelvic radiographs were normal except for sclerosis at the inferior half of the iliac bone adjacent to the right sacroiliac joint. Sedimentation rate, C-reactive protein, and whole blood counts were normal. Bone scan showed nonspecific increased uptake. Computed tomography revealed the presence of diffuse sclerosis at inferior half of the right iliac bone extending to medial border of sacroiliac joint with subcortical osteolytic region and centrally hyperdense sclerotic nidus inside.  相似文献   
100.
This study was conducted to define the value of procalcitonin (PCT) levels in the differential diagnosis of abdominal familial Mediterranean fever (FMF) attacks from acute appendicitis. From October 2006 to January 2007, 28 FMF (12 males, 16 females) patients with acute abdominal attacks and 34 patients (18 males) with acute abdomen who underwent operation with the clinical diagnosis of acute appendicitis were consecutively enrolled in this study. FMF patients with concurrent infectious diseases were excluded. PCT values were measured by an immunofluorescent method using the B.R.A.H.M.S. PCT kit (B.R.A.H.M.S. Diagnostica, Berlin, Germany). Erythrocyte sedimentation rate (ESR), C-reactive proteins (CRP) and leucocyte levels were also noted. Mean disease duration in FMF patients was 9.6 ± 8.1 years (range 2–33 years) and all were on colchicine therapy with a mean colchicine dosage of 1.2 ± 0.4 mg/day. Among the operated patients, 5 were excluded: 3 patients had normal findings and 2 had intestinal perforation (PCT levels were 2.69 and 4.93 ng/ml, respectively) at operative and pathologic evaluation. There were no significant differences between the two groups with respect to gender and age (p was not significant (NS) for all). Acute phase reactants and PCT levels were increased in patients with FMF compared to patients with acute appendicitis (0.529[0.12 ± 0.96] vs 0.095 [0.01–0.80] p < 0.001, respectively). PCT levels higher than 0.5 ng/ml were found in 11% (3/28) of FMF patients compared to 62% (18/29) of acute appendicitis patients (p < 0.001). Our results suggest that PCT could be a useful test in the differentiation of abdominal FMF attacks from acute appendicitis, though it should not supplant more conventional investigations.  相似文献   
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