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91.
OBJECTIVES: The vena contracta is the narrowest region of the regurgitant or stenotic jet just downstream the orifice and reflects the size of that orifice. This study was performed to assess the accuracy of the vena contracta width (VCW) in evaluating the severity of mitral stenosis (MS) and to compare the mitral valve area (MVA) determined by VCW with MVAs obtained by other more traditional echocardiographic methods. METHODS: We studied 59 patients (43 females, 42 +/- 14 years) with MS. VCW was measured in the apical four chamber view by Doppler color flow mapping. The largest diameter of the VCW during diastole was measured for at least three cardiac cycles and averaged. MVA was calculated from the following equation: pir(2), where r = VCW/2. MVA was also determined by planimetry, the pressure half-time method, and by the Gorlin formula. RESULTS: In this study, the width of the vena contracta ranged from 0.89 to 1.73 cm (mean 1.30 +/- 0.21). MVA, calculated based on the VCW, ranged from 0.63 to 2.35 cm(2) (mean 1.36 +/- 0.41). MVA by VCW (1.36 +/- 0.41 cm(2)) showed good correlations with three comparative techniques: (1) the cross-sectional area by planimetry (1.35 +/- 0.36 cm(2), mean difference = 0.21 +/- 0.16 cm(2), y = 0.91x + 0.14, r = 0.79, SEE = 0.26 cm(2), p < 0.001); (2) the area derived from the Doppler pressure half-time (1.27 +/- 0.32 cm(2), mean difference = 0.22 +/- 0.19 cm(2), y = 0.97x + 0.13, r = 0.76, SEE = 0.27 cm(2), p < 0.001), and (3) the area derived from the Gorlin equation in the 18 patients who underwent catheterization (1.27 +/- 0.35 cm(2), mean difference = 0.19 +/- 0.16, y = 0.98x + 0.05, r = 0.81, SEE = 0.26 cm(2), p < 0.001). CONCLUSIONS: These findings suggest that Doppler color flow imaging of the MS jet in the vena contracta can provide an accurate estimation of MVA and appears to be potentially applicable in the assessment of the severity of MS.  相似文献   
92.
OBJECTIVE: The efficacy and the effective dose of levothyroxine suppressive therapy in the treatment of benign thyroid nodules are controversial. In this study, we aimed to determine the response of solitary thyroid nodules to low- or high-level TSH suppression in a placebo-controlled, randomized crossover trial. DESIGN: Forty-nine patients with solitary thyroid nodules on palpation were randomized to high-level and low-level TSH suppression groups. In each group, patients were further randomized to placebo and active levothyroxine subgroups. Patients in each subgroup were crossed over to placebo or active levothyroxine at the end of the first year and were then followed up for an additional year. METHODS: TSH levels were suppressed to 0.4-0.6 mIU/ml and < or = 0.01 mIU/ml in the low-level and high-level TSH suppression groups, respectively. Nodule volumes were measured at baseline and every 6 months after the desired level of TSH was reached if the patients were in the active levothyroxine treatment group or every 6 months if they were in the placebo group. RESULTS: In high-level TSH suppression groups, nodule volume decreased significantly at the end of the active treatment periods (4.99 +/- 2.02 ml vs. 3.20 +/- 1.50 ml, P < 0.01, in Group 1; and 3.72 +/- 1.79 ml to 2.05 +/- 0.64 ml, P < 0.001, in Group 2). In the low-level TSH suppression groups, nodule volume also decreased significantly at the end of the active treatment periods (4.43 +/- 1.76 ml vs. 3.04 +/- 1.32, P < 0.05, in Group 3; and 3.59 +/- 0.89 ml to 2.22 +/- 0.59 ml, P < 0.01, in Group 4). Nodule volumes regained their original volumes during the placebo treatment periods. The percentage decline in clinically relevant nodule volume reduction (> or = 50%) was similar in the low-level and high-level TSH suppression groups. CONCLUSION: Low- and high-level TSH suppression were equally effective in reducing nodule volume and thus, considering the complications of high-level TSH suppression, low-level TSH suppression should be used if one considers levothyroxine suppressive therapy to reduce thyroid nodule size.  相似文献   
93.
We demonstrate a lensfree dual-mode holographic microscope that can image specimens in both transmission and reflection geometries using in-line transmission and off-axis reflection holography, respectively. This field-portable dual-mode holographic microscope has a weight of ~200 g with dimensions of 15 x 5.5 x 5cm, where a laser source is powered by two batteries. Based on digital in-line holography, our transmission microscope achieves a sub-pixel lateral resolution of ≤2 μm over a wide field-of-view (FOV) of ~24 mm(2) due to its unit fringe magnification geometry. Despite its simplicity and ease of operation, in-line transmission geometry is not suitable to image dense or connected objects such as tissue slides since the reference beam gets distorted causing severe aberrations in reconstruction of such objects. To mitigate this challenge, on the same cost-effective and field-portable assembly we built a lensless reflection mode microscope based on digital off-axis holography where a beam-splitter is used to interfere a tilted reference wave with the reflected light from the object surface, creating an off-axis hologram of the specimens on a CMOS sensor-chip. As a result of the reduced space-bandwidth product of the off-axis geometry compared to its in-line counterpart, the imaging FOV of our reflection mode is reduced to ~9 mm(2), while still achieving a similar sub-pixel resolution of ≤2 μm. We tested the performance of this compact dual-mode microscopy unit by imaging a US-air force resolution test target, various micro-particles as well as a histopathology slide corresponding to skin tissue. Due to its compact, cost-effective, and lightweight design, this dual-mode lensless holographic microscope might especially be useful for field-use or for conducting microscopic analysis in resource-poor settings.  相似文献   
94.

Objective

The most prominent problem resulting from decreased body function in older adults is declining quality of life. Walking and talking among older adults in peer group may become a nursing therapy to improve their quality of life. The objective of this study was to identify the impact of walking and talking intervention of quality of life among community dwelling older adults in Depok, Indonesia.

Method

This study applied quasi-experimental design with 43 and 40 older adults in the intervention and control group, respectively. The participants were selected using multistage random sampling method.

Results

Based on t test, the average quality of life score of older adults improved more significantly in the intervention group than that in the control group, with p value of 0.003, its mean p value < α, respectively. An ANCOVA analysis was used to detect confounding factors. The result showed that all characteristics have a p value of > 0.05, which means there were no confounding factors warranting further investigation.

Conclusions

It was concluded that walking and talking therapy in peer group significantly increase the quality of life of older adults.  相似文献   
95.
Background: The ventricular late potential (VLP) detected using the technique of signal average electrocardiography (SAECG) interacts with several factors, primarily time. Method: In this study, we examined the interaction, over time, of VLP with the initial ischemic burden and enzyme levels in acute myocardial infarction. Patients diagnosed as having acute myocardial infarction were included in the study. On the first day, the patients underwent enzyme analysis and electrocardiography (ECG) follow‐up every 6 hours. A 24‐hour ambulatory ECG was performed on the seventh day in order to determine the ischemic burden. SAECG findings (TQRS, RMS, LAS were obtained on the seventh day, in the first and third months. The study was continued with the patients who did not require angioplasty as decided with angiographic evaluation in the first month. Results: The study included 30 patients with acute myocardial infarction (mean age 51 ± 12, 28 males and 2 females). The initial mean CK‐MB levels and the mean ischemic burden were 98 ± 31 U/L and 44 ± 96 minutes. The TQRS (ms), LAS (ms), and RMS (μV) values (mean ± SD) obtained at day 7, month 1, and month 3 are 97 ± 12, 96 ± 9, 103 ± 11, P = 0.01; 31 ± 10, 31 ± 11, 32 ± 10, P = 0.46; 43 ± 28, 41 ± 26, 33 ± 25, P = 0.01, respectively. We observed that the TQRS and RMS values changed significantly with time, but these levels of significance disappeared when adjusted for the initial ischemic burden and CK‐MB levels (P = 0.06; P = 0.53). The VLP frequency was 33% at day 7 and 23% at month 3. Unlike the CK‐MB level, the initial ischemic burden was significantly different between the patients with and without VLP at month 3 (150.85 ± 149.28, 12.34 ± 26.48, P = 0.001). When tested together with age and gender, it was found that the high initial ischemic burden increased the possibility of VLP (OR: 24, Cl: 2.09–279.52, P = 0.01) at month 3. Conclusion: SAECG findings in patients with myocardial infarction changed with time; however, this change occurred depending on the initial ischemic burden and CK‐MB levels. Of these, only the initial ischemic burden, especially in high levels, was a determinant for the presence of VLP in the late period of myocardial infarction. A.N.E. 2002;7(3):242–246  相似文献   
96.
Background: The myocardial performance index (Tei index) is an echocardiographic index of combined systolic and diastolic functions. Brain natriuretic peptide (BNP) and its biologically inactive fragment N-terminal pro-BNP (NT-pro-BNP) are secreted by the heart in response to myocardial stretch. In this study, we investigated Tei index and NT-pro-BNP levels in patients with Wolff-Parkinson-White (WPW) syndrome before and after radiofrequency catheter ablation therapy (RFCA).
Methods: Thirty patients (19 males, 11 females, aged 35.5 ± 14.4 years) with WPW syndrome were enrolled in this study. Echocardiographic examination was performed before and 24 hours after RFCA. Tei index was calculated using Doppler echocardiography. Blood samples were taken before and 24 hours after RFCA to detect levels of NT-pro-BNP. Results: Although isovolumic contraction time (IVCT) and isovolumic relaxation time (IVRT) did not change, aortic ejection time (ET) was decreased after RFCA (276 ± 22 ms vs 254 ± 30 ms, P < 0.01). So Tei index was significantly higher in postablation period (0.36 ± 0.11 vs 0.42 ± 0.21, P < 0.05). NT-pro-BNP levels did not change significantly after RFCA. Conclusions: We demonstrated that restoration of normal atrioventricular conduction by RFCA, leads to increase in Tei index but does not effect plasma NT-pro-BNP levels .  相似文献   
97.
OBJECTIVE: In the present study, we attempted to analyze the coronary artery lesion characteristics of acute ST elevation myocardial infarction (STEMI) in young patients (aged less than 35 years). METHODS: We retrospectively surveyed 25 038 coronary angiography procedures, which were carried out at The Baskent University Adana Hospital from 1998 to present, to discover acute STEMI in young patients. We studied clinical risk factors and angiographic characteristics in 42 consecutive patients who underwent primary coronary angiography for acute STEMI. Control group (n=42) had no history of coronary artery disease and had angiographically proven normal coronary arteries. All patients were under 35 years of age. Angiographic features for STEMI group were collected and both groups were compared for coronary risk factors. RESULTS: Male sex was more prevalent in acute STEMI group when compared with control participants (83 vs. 59%, respectively; P=0.01). A significant difference was found in cigarette smoking (62 vs. 36%, respectively; P=0.007) and family history (33 vs. 16%, respectively; P=0.03) between the two groups. No statistical significance was observed between the groups in terms of hypertension, diabetes mellitus, total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels. Mean high-density lipoprotein cholesterol level was 33+/-8 mg/dl in STEMI group and 39+/-12 mg/dl in control participants (P=0.02). Young patients with acute STEMI showed a preponderance of single-vessel disease (69%) and acute anterior STEMI (60%) owing to occluded left anterior descending artery (P<0.001). CONCLUSION: We observed risk factors such as family history, smoking, and low high-density lipoprotein cholesterol levels in young adults. Acute anterior STEMI owing to occluded left anterior descending artery was more frequent. Coronary atherosclerosis was characterized by higher presence of type B and proximal lesions. The handling selection was percutaneous coronary intervention in more than half of the patients.  相似文献   
98.
Idiopathic pulmonary hemosiderosis (IPH) is a rare disease characterized by anemia, hemoptysis and recurrent alveolar hemorrhage. The combination of IPH and celiac disease (CD) is extremely rare. We report a 9-year-old boy with Lane-Hamilton syndrome, co-occurrence of pulmonary hemosiderosis with CD. This presentation is unique presentation because he has also retinal pigmentation.  相似文献   
99.
Fanconi anemia (FA) is a rare autosomal recessive disorder that presents with variable organ abnormalities, progressive cytopenia, and susceptibility to the development of several malignancies. Although some of the organ pathologies such as microcephaly, microphthalmia, skin dyspigmentation, urogenital system involvement, and radial ray skeletal abnormalities are relatively common, there are some other abnormalities that are rarely associated with the disease [Alter BP. In: Nathan DG, Oski FA, editors. Hematology of infancy and childhood. Philadelphia: Saunders; 2003. p 259-273]. In this paper, five cases of unrelated FA patients with unusual organ pathologies, including chronic obstructive lung disease, lipodystrophy, Sprengel's deformity, diaphragmatic hernia, and inflammatory linear verrucous epidermal nevus (ILVEN) are presented. Recognition of unusual pathologies associated with FA is important in order to improve our understanding of the relationship between the disease and presenting organ pathologies.  相似文献   
100.
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