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81.
Purpose: This study aimed to determine the relationship between macular thickness and spherical equivalent refraction (SER), axial length (AL) and vitreous chamber depth (VCD) in Malay subjects. Methods: Sixty‐three subjects (aged 19–24 years) with a mean SER of ‐1.79 ± 2.24 D, mean axial length of 24.26 ± 1.35 mm and mean vitreous chamber depth of 17.02 ± 1.33 mm were included in this clinical cross‐sectional study. Stratus optical coherence tomography (Time Domain optical coherence tomography) was used to determine the thickness of the outer macular (perifovea) and inner macular (parafovea) at four different locations, that is, temporal, superior, nasal and inferior quadrants and also the fovea itself. Results: Positive correlations were found between the outer macular (perifovea) thickness and SER at the temporal (R = 0.47, p < 0.05), superior (R = 0.36, p < 0.05) and inferior (R = 0.31, p < 0.05) quadrants. Foveal thickness was also positively correlated with AL (R = 0.34, p < 0.05) and VCD (R = 0.32, p < 0.05). Negative correlations were found between outer macular thickness and axial length at the temporal (R = ‐0.46, p < 0.05), superior (R = ‐0.27, p < 0.05), nasal (R = ‐0.25, p < 0.05) and inferior (R = ‐0.36, p < 0.05) quadrants. Negative correlations were also found between outer macular thickness and VCD at the temporal (R = ‐0.51, p < 0.05), superior (R = ‐0.32, p < 0.05), nasal (R = ‐0.31, p < 0.05) and inferior (R = ‐0.40, p < 0.05) quadrants. Conclusions: This study shows that the degree of myopia and elongation of the globe are associated with thinning of most areas of the perifovea. A trend for foveal thickening in the high myopia group is also inferred, although this does not apply to the low and moderate myopia groups.  相似文献   
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83.
A case of vasospasm after traumatic subarachnoid haemorrhage (SAH) is reported here. Transcranial Doppler Sonography (TCD) was used to evaluate mean flow velocity (MFV) changes of the basal cerebral arteries related to vasospasm. Accelleration of MFV of the right middle cerebral artery (MCA) indicating vasospasm was first noted on TCD evaluation, and then proved by carotid angiography (CAG). Evaluation of all TCD results revealed that the process of relaxation or normalization of the spastic artery started from the proximal side of the basal intracranial artery and gradually moving to the distal side. This interesting phenomenon could be a common process found in vasospasm cases.  相似文献   
84.
A new model of brainstem ischemia by embolization technique in cats   总被引:3,自引:0,他引:3  
An experimental model of brainstem ischemia was developed by embolization technique with cylindrical silicone rubber emboli in cats. The embolus reached the basilar artery in 55 cats (58.5%) and stopped in the upper basilar artery (UB) in 32, the middle basilar artery (MB) in 22 and the lower basilar artery (LB) in one animal. When the basilar artery distal to the embolus was not visualized (type 1) by postoperative vertebral angiogram. Evans blue extravasation was observed in the brainstem caudal to the embolus. When only a filling defect of the basilar artery at the site of the embolus was noted (type 2), dye extravazation was observed in the brainstem around the site of the embolus. In UB type 1, the regional cerebral blood flow of pons and medulla oblongata decreased immediately after embolization, and six hours after embolization it was 11.4±5.7 (pons) and 11.7±4.6 ml/100 g/min (medulla oblongata). In UB type 1 and MB type 1 animals, coma, apnea, tetraplegia, and disturbance of swallowing were noted. These animals died within 50 hours after embolization. Animals of UB type 2 and MB type 2 showed neurological deficits, but survived for three days. This paper discusses this method of producing experimental brainstem ischemia, the sites of ischemic lesions, and clinicopathological findings.  相似文献   
85.
Adhesive bond strength studies for the tray adhesive of an addition vinyl polysiloxane (President) impression material were conducted with an acrylic resin, chromium-plated brass, and plastic trays. Tensile and shear stress studies were performed on the Instron Universal testing machine. Acrylic resin specimens roughened with 80-grit silicon carbide paper exhibited appreciably higher bond strengths compared with different types of tray material and methods of surface preparation.  相似文献   
86.
INTRODUCTION: This study aims to determine the prevalence and the types of menstrual disorders among patients with systemic lupus erythematosus (SLE) and to identify factors that influence their development. METHODS: 61 patients with SLE were enrolled into a cross-sectional, observational study at the medical outpatient clinic, Hospital Universiti Sains Malaysia. A total of 120 healthy women were selected randomly to act as the control group. A questionnaire was administered, vital signs were recorded, and blood was evaluated for routine investigations. A review of past medical records was also undertaken. RESULTS: The mean age and standard deviation for the study group was 33.23 +/- 10.96 years, the majority being ethnic Malays. 75 percent had a severe SLE disease activity index score on initial presentation, and 59 percent were on cyclophosphamide. 49 percent of the study population had menstrual irregularities, of which 60 percent had sustained amenorrhoea. Nine patients with sustained amenorrhoea had hormonal assays, which confirmed the diagnosis of premature menopause. CONCLUSION: This study showed that SLE patients had a higher risk of developing menstrual irregularities compared to the normal/healthy population. The risk was higher in the older age group (greater than 30 years old) and those on cyclophosphamide therapy, especially those with a cumulative dose of more than 10 g. Sustained amenorrhoea was the commonest irregularity and a majority of them had confirmed premature menopause.  相似文献   
87.
88.

Objectives

Heart Quality of Life (HeartQoL) is a new “hybrid” developed from the MacNew and two condition-specific questionnaires measuring health-related quality of life (HRQoL) in patients with ischemic heart disease (IHD). This study investigates test–retest reliability of HeartQoL (English version) according to international criteria (e.g., COSMIN, GRRAS). Findings on HeartQoL are compared to the published data on MacNew in view that both serve as the core IHD-specific HRQoL instrument.

Methods

Out of 105 patients with IHD, 76 completed self-administration of HeartQoL at the clinic followed by at home within a 2-week interval. In retest, patients responded using non-interview methods (phone messaging, email, fax, and post). Phone interviewing was reserved for non-respondents to reminder.

Results

Reliability of HeartQoL was good (intraclass correlation coefficients = 0.78–0.82), was supported in the Bland–Altman plot, and was comparable to five studies on MacNew of similar retest interval (MacNew-English = 0.70–0.75; translated MacNew = 0.72–0.91). Applicability of its standard error of measurement (0.20–0.25) and smallest detectable change (0.55–0.70) will depend on availability of normative data in future.

Conclusion

The reliability of HeartQoL is comparable to its parent instrument, the MacNew. The HeartQoL is a potentially reliable core IHD-specific HRQoL instrument in measuring group change.
  相似文献   
89.
Coeliac artery thrombosis with ischaemia is a rare condition, which usually presents with severe peptic ulcer disease symptoms. It is usually associated with risk factors for thrombosis or embolism. The manifestation is rare because of large number of collaterals between the coeliac and superior mesentery artery. Early detection and intervention is required to prevent the progression of its complications that includes gastric ischaemic necrosis.  相似文献   
90.
Oral squamous cell carcinoma (OSCC) has a propensity to spread to the cervical lymph nodes (LN). The presence of cervical LN metastases severely impacts patient survival, whereby the two-year survival for oral cancer patients with involved LN is ~30% compared to over 80% in patients with non-involved LN. Elucidation of key molecular mechanisms underlying OSCC metastasis may afford an opportunity to target specific genes, to prevent the spread of OSCC and to improve patient survival. In this study, we demonstrated that expression of the heterotrimeric G-protein alpha-12 (Gα12) is highly up-regulated in primary tumors and LN of OSCC patients, as assessed by quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC). We also found that exogenous expression of the constitutively activated-form of Gα12 promoted cell migration and invasion in OSCC cell lines. Correspondingly, inhibition of Gα12 expression by shRNA consistently inhibited OSCC cell migration and invasion in vitro. Further, the inhibition of G12 signaling by regulator of G-protein signaling (RGS) inhibited Gα12-mediated RhoA activation, which in turn resulted in reduced LN metastases in a tongue-orthotopic xenograft mouse model of oral cancer. This study provides a rationale for future development and evaluation of drug candidates targeting Gα12-related pathways for metastasis prevention.  相似文献   
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