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1.
This review sets out to explore the relationship between the lateral pterygoid muscle and the meniscus. It examines the embryological evidence to explain the controversy surrounding the apparent morphological discrepancy in the attachment of the lateral pterygoid muscle to the meniscus. It shows that the contribution of the lateral pterygoid muscle to the formation of the meniscus remains in dispute. Morphogenetic studies have not been able to support either one or other viewpoint and no direct conclusions can therefore be made on the embryology of the temporomandibular joint.  相似文献   
2.
Siphonochilus aethiopicus is an indigenous South African plant also known as African ginger. It has often been used for its medicinal properties to treat various ailments such as flu, colds, and so forth. The research aim of this study was to optimize the process parameters of steam distillation for the extraction of oil from African ginger rhizomes. This technology is the oldest and well known for extracting essential oils due to its economic viability and the higher final oil purity. The effects of operating parameters such as extraction duration, moisture content, particle size, and temperatures between 80°C and 100°C were studied for maximum oil recovery. The oil recovery of 0.61% (w/w) was achieved after 270?min of extraction time, using 6.37% (dry) moisture content of particle size 2.4?mm–4?mm at a maximum temperature of 100°C. Fick’s first law was used to mathematically model the experimental data of this study.  相似文献   
3.
This paper describes the design of a 16-electrode high-speed (1000 frames/s) electrical resistance tomography system with real-time visualization. The instrument utilizes a switched dc current pulse technique in conjunction with parallel data acquisition to achieve the high-data capture rates. The reconstruct algorithm is implemented using a single iteration Newton-Raphson method, which executes in under 1 ms. Data sets are presented that verify its operation. A calibration technique is described which improves the sensitivity of the current pulse measuring system and allows phenomena such as the dynamics of nonuniform slurries and gas distribution in aeration systems to be investigated. Furthermore, the calibration scheme described compensates significantly for the effect of impellers and baffles present in the measuring tank and allows more accurate reconstructions to be performed in the areas of interest.  相似文献   
4.
We investigated whether exposure to microbiome within the indoor environment is associated with risk of lower respiratory tract infections (LRTI) among children under 5 years of age. Electronic scientific repositories; PubMed, Scopus, Web of Science, GreenFILE, EMBASE, and Cochrane library were searched and screened through July 2019 for published reports for inclusion in the meta-analysis. Studies were eligible for inclusion if they reported an adjusted measure of risk for LRTI associated with IM exposure, including the relative risk (RR) or odds ratio (OR) and confidence interval (CI). The pooled OR was computed using the inverse of variance method for weighting. Sensitivity analysis was used to evaluate the effect of individual studies, while heterogeneity was evaluated by I2 statistics using RevMan 5.3. Seven studies were eligible for inclusion in our meta-analysis. Exposure to a higher concentration of IM was associated with an increased risk of LRTI [OR:1.20 (1.11, 1.33), P < .0001]. The risk was stronger with exposure to total fungal concentration [OR:1.27 (1.13, 1.44), P < .0001] than visible molds [OR:1.20 (1.07, 1.34, P = .001]. Under-five children exposed to higher IM concentration are likely at increased risk of LRTI. Interventions addressing IM exposure should be considered in the management of LRTI among under-five children.  相似文献   
5.
The health impact of indoor air pollution in informal settlement households has not been extensively studied in South Africa. This cross‐sectional study investigated the association between asthma and common indoor exposures among schoolchildren from four informal settlements located in two municipalities in the Western Cape Province. A total of 590 children, aged 9‐11 years, were recruited. The International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was administered to caregivers. Pulmonary function assessment included spirometry and fractional exhaled nitric oxide (FeNO). Phadiatop test for atopy was done. The prevalence of doctor‐diagnosed asthma was 3.4% (n = 20) among whom only 50% were on treatment. The prevalence of current wheeze was 12.9%, and 17.6% had airway obstruction (FEV1 < lower limit of normal), while 10.2% had airway inflammation (FeNO > 35 ppb). In adjusted logistic regression models, dampness, visible mold growth, paraffin use for cooking, and passive smoking were associated with a twofold to threefold increased risk in upper and lower airway outcomes. The strongest association was that of visible mold growth with rhinitis (adjusted odds ratio—aOR 3.37, 95% CI: 1.69‐6.71). Thus, there is a need for improved diagnosis of childhood asthma and Indoor Air Quality in informal settlement households.  相似文献   
6.
Adverse drug reactions (ADRs) rank as one of the top 10 leading causes of death and illness in developed countries. ADRs show differential features depending upon genotype, age, sex, race, pathology, drug category, route of administration, and drug–drug interactions. Pharmacogenomics (PGx) provides the physician effective clues for optimizing drug efficacy and safety in major problems of health such as cardiovascular disease and associated disorders, cancer and brain disorders. Important aspects to be considered are also the impact of immunopharmacogenomics in cutaneous ADRs as well as the influence of genomic factors associated with COVID-19 and vaccination strategies. Major limitations for the routine use of PGx procedures for ADRs prevention are the lack of education and training in physicians and pharmacists, poor characterization of drug-related PGx, unspecific biomarkers of drug efficacy and toxicity, cost-effectiveness, administrative problems in health organizations, and insufficient regulation for the generalized use of PGx in the clinical setting. The implementation of PGx requires: (i) education of physicians and all other parties involved in the use and benefits of PGx; (ii) prospective studies to demonstrate the benefits of PGx genotyping; (iii) standardization of PGx procedures and development of clinical guidelines; (iv) NGS and microarrays to cover genes with high PGx potential; and (v) new regulations for PGx-related drug development and PGx drug labelling.  相似文献   
7.
It has formerly been shown that low-damage levels, produced during the implantation doping of diamond as a semiconductor, anneal easily while high levels “graphitize” (above about 5.2 × 1015 ions/cm2). The difference in the defect types and their profiles, in the two cases, has never been directly observed. We have succeeded in using cross-section transmission electron microscopy to do so. The experiments were difficult because the specimens must be polished to ∼40 μm thickness, then implanted on edge and annealed, before final ion beam thinning to electron transparency. The low-damage micrographs reveal some deeply penetrating dislocations, whose existence had been predicted in earlier work.  相似文献   
8.
9.
BACKGROUND: Coronary heart disease (CHD) has reached 'epidemic' proportions in South Africa. CHD is uncommon in the black population of South Africa, yet the prevalence of hypertension in the adult black population is high. DESIGN: This study compared the blood pressure profile in 154 medical students of which 83 were Indians (1), 71 were black (B), 87 were male (50 I, 37 B), and 67 were female (33 I, 34 B) age 21 (SD+/-1.6), using the cuff method and 24 h ambulatory blood pressure monitoring (ABPM). METHODS: All students underwent ABPM. Biochemical studies for CHD risk factors were done. Electrocardiography (ECG) was performed in all participants and echocardiography in 90. RESULTS: ABPM showed that black students had higher systolic and diastolic blood pressure throughout the day, night and critical time periods compared with the Indian students. Blood pressure load was higher in black (40.8%) than in Indian participants (29.6%; P<0.05) and there was less dipping at night Left ventricular mass was significantly higher in black than in Indian participants (29.6%; P<0.05) and there was less dipping at night. Left ventricular mass was significantly higher in black than in Indian participants. Risk factors leading to CHD were more common in Indian than in black participants. Those with borderline hypertension (blood pressure > or = 130/85 and < or = 140/90 mmHg) had statistically higher serum triglyceride and left ventricular mass than normotensives. CONCLUSIONS: Young black people had higher blood pressure readings than young Indian participants in the absence of metabolic abnormalities and had greater cardiac involvement Borderline hypertension is not innocuous. Metabolic risk factors for CHD in Indian people are apparent at an early age. This study emphasizes the need for prevention of risk factors leading to CHD at an early age.  相似文献   
10.
Estrone (E1) and Estriol (E3) are endogenous female hormones, present in increased concentrations during female specific physiological processes (menopause and pregnancy respectively) that are associated with increased venous thrombotic risk. These hormones are also used as hormone therapies that are also associated with increased thromboembolism risk. Viscoelastic analysis revealed no significant difference to clot formation after hormone addition, however morphological analysis showed that the addition of both E1 and E3 result in fibrin clots composed of thinner fibrin fibers arranged in dense matted networks. These changes to the fibrin network ultrastructure are indicative of a prothrombotic state but may also indicate hypofibrinolysis. We therefore conclude that the increased risk of venous thrombosis during pregnancy and menopause may originate from a combination of hypercoagulation and a possible hypofibrinolytic mechanism of these hormones. Therefore females with a hypercoagulable tendency that fall pregnant or enter menopause need to be monitored to prevent venous thrombotic events. The decision to use hormone therapies during and after menopause should not be taken lightly and the risk‐reward scale should be closely examined to ensure it does not tip towards thrombosis and subsequent thrombotic events that ultimately could have been prevented.  相似文献   
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