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101.
Muscle herniation is a focal protrusion of muscle tissue through a defect in the deep fascial layer. Anterior tibial muscle is the most commonly affected muscle of the lower extremities because its fascia is the most vulnerable to trauma. Clinically it is characterized by asymptomatic or painful, skin‐coloured, soft, subcutaneous nodules of various size depending on the position. The diagnosis is usually made clinically based on its typical manifestations, but ultrasonographic examination is useful for detecting the fascial defect and excluding other conditions caused by soft tissue tumours such as lipomas, angiolipomas, fibromas, scwhannomas or varicosities. Although this entity is not rare, it has been less well documented in the dermatological literature. We report a case of bilateral tibialis anterior muscle herniation mimicking a soft tissue tumour in a young amateur football player.  相似文献   
102.
In clinical trials, it is important to set up a design to reach a decision on effectiveness of a drug in treating a disease with the loss of the minimum number of patients. Group sequential designs are very beneficial on this point. However, the proportional hazards assumption must hold to work under a group sequential design properly. A trial running under a group sequential design covers a long time period; therefore, assuming that hazards remain proportional over a long time period is somewhat unrealistic. We should examine and figure out the impact of nonproportional hazards over the hypothesis tests conducted under a group sequential design to set up more reliable designs and decide which test to use in which conditions. In this article, powers of group sequential tests with nonparametric statistics are evaluated under nonproportional hazards by a Monte Carlo simulation study. The simulation study covers different nonproportional hazards scenarios, censoring rates, survival distributions, sample sizes, and tied observations. With this study, we intend to be helpful for clinical trial designers to set up a more reliable group sequential design.  相似文献   
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The Cavalieri estimator using a point grid is used to estimate the volume of three-dimensional structures based on two-dimensional slices of the object. The size of the components of intracranial neural structures should have proportional relations among them. The volume fraction approach of stereological methods provides information about volumetric relations of the components of structures. The purpose of our study is to estimate the volume and volume fraction data related to the cerebrum, cerebellum and brain stem. In this study, volume of the total brain, cerebrum, cerebellum and brain stem were estimated in 24 young Turkish volunteers (12 males and 12 females) who are free of any neurological symptoms and signs. The volume and volume fraction of the total brain, cerebrum, cerebellum and brain stem were determined on magnetic resonance (MR) images using the point-counting approach of stereological methods. The mean (+/-SD) total brain, cerebrum and cerebellum volumes were 1,202.05 +/- 103.51, 1,143.65 +/- 106.25 cm(3) in males and females, 1,060.0 +/- 94.6, 1,008.9 +/- 104.3 cm(3 )in males and females, 117.75 +/- 10.7, 111.83 +/- 8.0 cm(3) in males and females, respectively. The mean brain stem volumes were 24.3 +/- 2.89, 22.9 +/- 4.49 cm(3) in males and females, respectively. Our results revealed that female subjects have less cerebral, cerebellar and brain stem volumes compared to males, although there was no statistically significant difference between genders (P > 0.05). The volume ratio of the cerebrum to total brain volume (TBV), cerebellum to TBV and brain stem to TBV were 88.16 and 88.13% in males and females, 9.8 and 9.8% in males and females, 2.03 and 2.03% in males and females, respectively. The volume ratio of the cerebellum to cerebrum, brain stem to cerebrum and brain stem to cerebellum were 11.12 and 11.16% in males and females, 2.30 and 2.31% in males and females, 20.7 and 20.6% in males and females, respectively. The difference between the genders was not statistically significant (P > 0.05). Our results revealed that the volumetric composition of the cerebrum, cerebellum and brain stem does not show sexual dimorphism.  相似文献   
105.
There are over 3 million truck drivers employed in the commercial transportation and material moving occupations, one of the largest occupational groups in the United States. Workers in this large and growing occupational segment are at risk for a range of occupational health-induced conditions, including mental health and psychiatric disorders due to high occupational stress, low access and use of health care, and limited social support. The purpose of this study was to explore male truck drivers' mental health risks and associated comorbidities, using a cross-sectional and quantitative design. Data were collected from a random sample of 316 male truckers between the ages of 23 and 76 at a large truck stop located within a 100-mile radius of Greensboro, North Carolina, USA, using a self-administered 82-item questionnaire. Surveyed truckers were found to have significant issues affecting their mental health, such as loneliness (27.9%), depression (26.9%), chronic sleep disturbances (20.6%), anxiety (14.5%), and other emotional problems (13%). Findings have potential to help researchers develop interventions to improve the emotional and occupational health of truck drivers, a highly underserved population. Mental health promotion, assessment, and treatment must become a priority to improve the overall trucking environment for truckers, the transportation industry, and safety on US highways.  相似文献   
106.
The endocannabinoids and their attending cannabinoid (CB)(1) receptors have been implicated in the control of cognition, but their possible roles in dementias are still unclear. In the present study, we used liquid chromatography/mass spectrometry to conduct an endocannabinoid-targeted lipidomic analysis of postmortem brain samples from 38 Alzheimer's disease (AD) patients and 17 control subjects, matched for age and postmortem interval. The analysis revealed that midfrontal and temporal cortex tissue from AD patients contains, relative to control subjects, significantly lower levels of the endocannabinoid anandamide and its precursor 1-stearoyl, 2-docosahexaenoyl-sn-glycero-phosphoethanolamine-N-arachidonoyl (NArPE). No such difference was observed with the endocannabinoid 2-arachidonoyl-sn-glycerol or 15 additional lipid species. In AD patients, but not in control subjects, statistically detectable positive correlations were found between (1) anandamide content in midfrontal cortex and scores of the Kendrick's Digit Copy test (p = 0.004, r = 0.81; n = 10), which measures speed of information processing; and (2) anandamide content in temporal cortex and scores of the Boston Naming test (p = 0.027, r = 0.52; n = 18), which assesses language facility. Furthermore, anandamide and NArPE levels in midfrontal cortex of the study subjects inversely correlated with levels of the neurotoxic amyloid peptide, amyloid β-protein (Aβ)(42), while showing no association with Aβ(40) levels, amyloid plaque load or tau protein phosphorylation. Finally, high endogenous levels of Aβ(42) in Swedish mutant form of amyloid precursor protein (APP(SWE))/Neuro-2a cells directly reduced anandamide and NArPE concentrations in cells lysates. The results suggest that an Aβ(42)-dependent impairment in brain anandamide mobilization contributes to cognitive dysfunction in AD.  相似文献   
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108.
Tumour necrosis factor-alpha (TNF-α) antagonist drugs have been associated with increased risk of tuberculosis (TB). Tuberculin skin test (TST) is the most frequently used tool for identification of latent TB infection. We herein aimed to analyse the effect of TNF-α antagonists on the TST responses in a prospective study. The study group consisted of 182 patients (99 female, 83 male) who received TNF-α antagonists for various rheumatic disorders. All patients were evaluated with TST along with other parameters on the day of referral and on the 12th month visit. For those patients with a response of <5 mm induration at the initial evaluation, the TST was repeated to observe the booster effect. Out of 182 patients, 87 patients (48%) had a negative (0–4 mm) and 95 (52%) had a positive (≥5 mm) TST response at initial evaluation. The TST responses were converted from negative at initial visit to positive at 1-year repeat in 26 (30%) patients. A significant increase was observed in the diameters of TST that were repeated on the first year of TNF-α antagonist treatment (9.15 ± 0.55) compared to their initial diameters (6.60 ± 0.51) (P < 0.001). Increased TST responses in patients receiving TNF-α antagonists may be associated with the restoration of suppressed immune reactivity against TB antigens with the decreased disease activity. The meaning of TST conversion in the definition of latent TB infection and the need for chemoprophylaxis in these patients remains to be answered by further studies.  相似文献   
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