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71.
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Background: A case control study was carried out to study the emerging risk factors for coronary artery disease in Indians.  相似文献   
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BACKGROUND: Discrepancy between efficacy of prophylactic lithium and its effectiveness in ordinary clinical practice necessitates long-term follow-up data from specialised lithium clinics. Also, role of psychosocial factors in influencing the outcome is unclear. METHODS: One hundred and eighteen patients of bipolar affective disorder attending a lithium clinic were followed-up for approximately 11 years (range 2-27 years). Demographic and clinical data, measures of social support and psychosocial stress were obtained at the intake in 1989-1990. Study design combined retrospective chart-review (till the time of intake) with prospective follow-up till July 1995. RESULTS: On lithium, the patients had a mean of 0.43 relapses per year (manic, 0.26; depressive, 0.17) which was significantly less (p < 0.01) than the pre-lithium episode frequency. The figure for entirely relapse-free patients was 24%, and 62% had relapses up to one episode per year (median = 0.3 per year). Fifty-eight (49%) patients were good responders to lithium (relapses < or = 0.30 per year). In comparison to good responders, partial/poor responders had a significantly greater number of pre-lithium depressive episodes, poor lithium compliance, more psychosocial stress and lower social support at intake. These variables correlated well with relapses and explained 32% of the variance of the data. CONCLUSIONS: Lithium had a definite prophylactic effect on long-term outcome. Social support and stressful life events are significant correlates of response to lithium. CLINICAL IMPLICATIONS: Lithium prophylaxis of bipolar affective disorders seems justified though psychosocial factors appear to modulate its effectiveness. LIMITATIONS: Other psychotropic medications were used during relapse and the assessment of psychosocial factors was cross-sectional.  相似文献   
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Background

Systemic treatment of head and neck squamous cell carcinoma (HNSCC) includes a variety of antineoplastic drugs. However, drug-resistance interferes with the effectiveness of chemotherapy. Preclinical testing models are needed in order to develop approaches to overcome chemoresistance.

Methods

Ten human cell lines were obtained from HNSCC, including one with experimentally-induced cisplatin resistance. Inhibition of cell growth by seven chemotherapeutic agents (cisplatin, carboplatin, 5- fluorouracil, methotrexate, bleomycin, vincristin, and paclitaxel) was measured using metabolic MTT-uptake assay and correlated to clinically-achievable plasma concentrations.

Results

All drugs inhibited cell growth in a concentration-dependent manner with an IC50 comparable to that achievable in vivo. However, response curves for methotrexate were unsatisfactory and for paclitaxel, the solubilizer cremophor EL was toxic. Cross-resistance was observed between cisplatin and carboplatin.

Conclusion

Chemosensitivity of HNSCC cell lines can be determined using the MTT-uptake assay. For DNA-interfering cytostatics and vinca alkaloids this is a simple and reproducible procedure. Determined in vitro chemosensitivity serves as a baseline for further experimental approaches aiming to modulate chemoresistance in HNSCC with potential clinical significance.  相似文献   
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Objective  We investigated the application of high-resolution microarray-based comparative genomic hybridisation (array CGH) on a fetus showing increased nuchal translucency (NT).
Design  Case study.
Setting  Tertiary referral obstetrics unit.
Sample  Pregnant woman attended the antenatal clinic.
Methods  Conventional karyotyping and genetic test was carried out for the alpha-globin gene. High-resolution array CGH using the high-density 244K Agilent microarray was performed on fetal blood sample by cordocentesis to investigate the possibility of any genomic imbalance.
Main outcome measures  Detection of chromosomal abnormality.
Results  Karyotyping analysis showed 46,XY. Molecular genetic diagnosis confirms the fetus has Hb-H constant spring disease but cannot explain the increased NT to 3.2 mm. Array CGH analysis discovered a 1.32-Mb microdeletion on chromosome 16p13.11. Deletion at 16p13.11 has been implicated to predispose to autism and/or mental retardation. Baby was delivered at 40 weeks of gestation, and follow up was carried out at 3 months of age without sign of mental retardation/developmental delay.
Conclusions  This case study demonstrated that array CGH can accurately calibrate the size and identify de novo interstitial chromosome imbalances. However, the presence of chromosome copy variants with unknown clinical significance currently limits its wider scale application in prenatal diagnosis and needs further investigations.  相似文献   
78.
Background:  The aim of this work was to image trabeculectomy blebs using spectral domain optical coherence tomography (SDOCT).
Methods:  In this prospective cross-sectional study, patients who had undergone trabeculectomy with at least 3 months of follow up were included. Blebs were imaged using an adapted SDOCT system (Cirrus HD-OCT, Carl Zeiss Meditec Inc., Dublin, CA, USA) and time domain anterior segment optical coherence tomography (ASOCT) (Visante OCT, Carl Zeiss Meditec Inc.). An observer masked to clinical data assessed the utility of SDOCT and ASOCT in visualizing structures in successful and failed blebs.
Results:  Fifty-one eyes were imaged, of which 43 (84.3%) were successful. SDOCT showed wall thickening (93.0% vs. 67.4%, P  = 0.006) and discrete hyporeflective spaces in the wall (88.4% vs. 14.0%, P  < 0.0001) in a greater proportion of successful blebs than ASOCT. SDOCT showed the bleb cavity (23.3% vs. 48.8%, P  = 0.02), scleral flap (34.9% vs. 90.7%, P  < 0.0001), subflap space (20.9% vs . 72.1%, P  < 0.0001) and ostium (9.3% vs. 88.4%, P  < 0.0001) in fewer successful blebs than ASOCT. The internal ostium was not visualized in any failed bleb using SDOCT, whereas ASOCT showed the ostium in 87.5% of failed blebs ( P  = 0.001). SDOCT showed cystic spaces in the bleb wall in a greater proportion of successful blebs than failed blebs (88.4% vs. 37.5%, P  = 0.005).
Conclusions:  SDOCT imaging was able to show fine superficial features in the bleb wall. However, SDOCT had limited clinical utility in that it did not provide useful information about deep features such as flap position, bleb cavity formation or patency of the subflap space and internal ostium.  相似文献   
79.
Neonatal hypertension occurs in 2% of all infants and it is caused by renovascular abnormalities in 70% of these infants. The gold standard for diagnosing renovascular disease is conventional renal angiography. However, in neonates the procedure is not commonly used because of its invasive and technically challenging nature. MRI and MR angiography (MRA) are less invasive yet reliable means of detecting renovascular disease in adults. There is minimal literature on the use of MRI/MRA in neonatal hypertension. We report a neonate with hypertension secondary to a renovascular abnormality in which MRI/MRA was helpful in uncovering segmental renal artery stenosis. The infant underwent partial nephrectomy with subsequent resolution of his hypertension. Further studies are needed to validate the use of MRI/MRA in the evaluation of neonatal hypertension.  相似文献   
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