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1.
The effects of Nd-YAG laser irradiation on platelet function in vitro were studied using platelet rich plasma obtained from the blood of healthy volunteers. Laser delivery was effected via the bare optical fibre, thermal hot tip fibre and spectraprobe and the effects of these probes on platelet function were compared. Fall in platelet count and mean platelet volume (MPV) were proportional to increasing energy delivery with all three probes, the effect being maximal with the spectraprobe, moderate with the hot tip and least with the bare optical fibre. A significant decrease in percentage aggregation of platelets in response to added ADP, collagen and ristocetin with increasing energy delivery was also observed with all three probes. The formation of preformed aggregates, however, showed an increase proportional to energy delivery with all three probes.The differential effects of the various probes used in this study on platelet function may enhance our understanding of the complex role played by platelets in the pathogenesis of complications such as arterial thrombosis and re-occlusion after laser angioplasty.  相似文献   
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The degree of stenosis in the carotid artery can be predicted using automated carotid lumen diameter (LD) measured from B-mode ultrasound images. Systolic velocity-based methods for measurement of LD are subjective. With the advancement of high resolution imaging, image-based methods have started to emerge. However, they require robust image analysis for accurate LD measurement. This paper presents two different algorithms for automated segmentation of the lumen borders in carotid ultrasound images. Both algorithms are modeled as a two stage process. Stage one consists of a global-based model using scale-space framework for the extraction of the region of interest. This stage is common to both algorithms. Stage two is modeled using a local-based strategy that extracts the lumen interfaces. At this stage, the algorithm-1 is modeled as a region-based strategy using a classification framework, whereas the algorithm-2 is modeled as a boundary-based approach that uses the level set framework. Two sets of databases (DB), Japan DB (JDB) (202 patients, 404 images) and Hong Kong DB (HKDB) (50 patients, 300 images) were used in this study. Two trained neuroradiologists performed manual LD tracings. The mean automated LD measured was 6.35 ± 0.95 mm for JDB and 6.20 ± 1.35 mm for HKDB. The precision-of-merit was: 97.4 % and 98.0 % w.r.t to two manual tracings for JDB and 99.7 % and 97.9 % w.r.t to two manual tracings for HKDB. Statistical tests such as ANOVA, Chi-Squared, T-test, and Mann-Whitney test were conducted to show the stability and reliability of the automated techniques.  相似文献   
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Introduction: Certain frail patients fail to achieve adequate functional or mortality benefit despite successful transcatheter aortic valve replacement (TAVR). Therefore, frailty assessment methods are becoming an important tool to identify and intervene on this high-risk patient subset for improving clinical outcomes.

Areas covered: The authors provide an overview of frailty and frailty assessment tools being used in clinical practice and discuss the impact of frailty on the cardiac patients, particularly among the TAVR population.

Expert commentary: Available evidence suggests that frailty assessment is critical for identifying patients at high risk of morbidity and mortality after TAVR procedures. However, there is lack of consensus for the best methodology to determine frailty and its optimal management in TAVR populations. Although, physical exercise is a commonly employed intervention to reduce frailty, a greater attention towards improving nutrition may convey more benefit than either intervention alone. Ongoing studies are investigating the benefits of a multicomponent approach to improve clinical outcomes in frail patients undergoing TAVR.  相似文献   

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Background

Low‐carbohydrate diets are becoming increasingly popular, although their dietary quality outside of clinical studies is unknown. A previous study analysed the dietary intake in people consuming a reduced‐carbohydrate diet (<40% calories). However, it is not clear what foods people consume when carbohydrate is reduced to below 26% of total calories.

Methods

In the present cross‐sectional study, the dietary and nutrient intake collected via up to five consecutive 24‐h dietary recalls and a food frequency questionnaire of 444 individuals (aged 46‐79 years) consuming <26% of calories from carbohydrate (LCHO ) was compared with that of 131 897 individuals consuming ≥45% calories from carbohydrate (NCHO ) using the UK Biobank Dataset. Absolute cut‐offs to define the low‐carbohydrate group (<130 g day–1; n  = 1953 versus ≥225 g day–1, n  = 113 036) were also used.

Results

Both NCHO (>45% calories and ≥225 g) groups consumed significantly more high‐sugar, high‐fat snacks [median 6.0, interquartile range (IQR ) = 2.0–11.0 and median 6.0, IQR  = 3.0–11.8, respectively) compared to the LCHO (<26% calories and <130 g) groups (median 0, IQR  = 0–2.8 and median 1, IQR  = 0–3.8, respectively) (P  < 0.0001). Both LCHO groups reported consuming significantly more red meat, oily fish, nuts and seeds but fewer fruits, vegetables and pulses compared to the NCHO groups. In general, the consumption of oily fish, nuts, seeds and pulses was low across the whole cohort and differences in intake between the LCHO and NCHO groups were small. After adjusting for socio‐economic status, most differences remained.

Conclusions

Carbohydrate restriction is associated with both beneficial and potentially deleterious dietary changes compared to a normal carbohydrate intake.
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Insertion–deletion polymorphism (Indels) is valuable diallelic markers for forensic as well as parentage analysis. The Investigator DIPplex Kit (Qiagen) contains thirty autosomal Indels markers along with amelogenin. These thirty markers were tested in the Pakistani Punjabi Population but no significant deviations were observed from Hardy–Weinberg equilibrium rule expectations (Bonferroni corrected) except HLD58, HLD56, HLD99, and HLD40. The mean expected and observed heterozygosity was found 0.4701 and 0.4667 respectively; combined matching probability was computed as 7.31867 × 10−13. However, the use of the 30 Indels markers proved to be a good supplementary tool in forensic casework, particularly when evidence sample is highly degraded. The significant genetic differences were also observed between the Punjabi and other populations of the world.  相似文献   
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Y-STR polymorphism of Gujjar population was determined by using AmpFISTR®YfilerTM PCR amplification kit. A total 176 haplotypes were obtained after the analysis of 17 Y-STR loci in 176 genetically unrelated individuals. Haplotype diversity and discrimination capacity attained was 0.99730 and 0.652201325, respectively. The comparison of Gujjar population with 16 other populations revealed that Gujjars have low genetic distance from Punjabi, Sindhi, and Pakhtun population of Pakistan; Azad Kashmir, Saraswat Brahmin from India; Bangladeshi population; north and south of Afghanistan; and Uttar Pradesh India which hints toward the migrational route Gujjars took over the centuries. This data is of significant value for population studies and forensic applications.  相似文献   
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Congenital rhabdomyosarcomas (RMSs) are rare tumors with variable clinical presentations. A 2 month-old, term male neonate (37 weeks, 4 days), weighing 3.2 kg, born to a 24 year-old primigravida, by simple vaginal delivery presented with multiple erythematous papulonodular lesions over his trunk that progressed to his whole body, on the first day of delivery. Prior to conception, his mother was treated for polycystic ovarian disease. On the tenth day, his chest computed tomogram scans revealed multiple, heterogeneously enhancing, bilateral pleural-based soft tissue density nodular lesions, along with multiple soft tissue density lesions, involving skeletal muscles of all his body parts. Microsections from two biopsies (on 10th day and after 2 months) revealed a malignant round cell tumor with cells arranged in a diffuse, solid pattern, comprising embryonal and solid alveolar components. Immunohistochemically, the tumor cells were diffusely positive for desmin, myoD1 and myogenin. Diagnosis of embryonal and alveolar (mixed type) RMS was offered. Further molecular cytogenetic analysis was negative for PAX3-FKHR and PAX7-FKHR. The patient was induced on chemotherapy as per intergroup rhabdomyosarcoma study IV protocol. There was treatment response with near total remission after 8 weeks of treatment. Thereafter, new lesions started appearing that also disappeared after modification of the chemotherapy drugs. However, after 16 months, the baby died of brain metastasis. The present case forms the fourth case report of an aggressive form of a congenital RMS with extensive cutaneous involvement and brain metastasis. A review of previously diagnosed cases of congenital RMSs is discussed herewith.  相似文献   
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