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31.
Striated intramural gallbladder lucencies on US studies: predictors of acute cholecystitis 总被引:1,自引:0,他引:1
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent. 相似文献
32.
Mak Susanne Hunt Matthew Boruff Jill Zaccagnini Marco Thomas Aliki 《Advances in health sciences education : theory and practice》2022,27(3):793-815
Advances in Health Sciences Education - Professional identity is believed to foster self-confidence and resilience in health care professionals. While literature exists describing professional... 相似文献
33.
Xue Yang Benjamin H K Yip Arthur D P Mak Dexing Zhang Eric K P Lee Samuel Y S Wong 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundSocial media has become a ubiquitous part of daily life during the COVID-19 pandemic isolation. However, the role of social media use in depression and suicidal ideation of the general public remains unclear. Related empirical studies were limited and reported inconsistent findings. Little is known about the potential underlying mechanisms that may illustrate the relationship between social media use and depression and suicidal ideation during the COVID-19 pandemic.ObjectiveThis study tested the mediation effects of social loneliness and posttraumatic stress disorder (PTSD) symptoms on the relationship between social media use and depressive symptoms and suicidal ideation, as well as the moderation effect of age on the mediation models.MethodsWe administered a population-based random telephone survey in May and June 2020, when infection control measures were being vigorously implemented in Hong Kong. A total of 1070 adults (658 social media users and 412 nonusers) completed the survey. Structural equation modeling (SEM) and multigroup SEM were conducted to test the mediation and moderation effects.ResultsThe weighted prevalence of probable depression was 11.6%; 1.6% had suicidal ideation in the past 2 weeks. Both moderated mediation models of depressive symptoms (χ262=335.3; P<.05; comparative fit index [CFI]=0.94; nonnormed fit index [NNFI]=0.92; root mean square error of approximation [RMSEA]=0.06) and suicidal ideation (χ234=50.8; P<.05; CFI=0.99; NNFI=0.99; RMSEA=0.02) showed acceptable model fit. There was a significantly negative direct effect of social media use on depressive symptoms among older people (β=–.07; P=.04) but not among younger people (β=.04; P=.55). The indirect effect via PTSD symptoms was significantly positive among both younger people (β=.09; P=.02) and older people (β=.10; P=.01). The indirect effect via social loneliness was significant among older people (β=–.01; P=.04) but not among younger people (β=.01; P=.31). The direct effect of social media use on suicidal ideation was not statistically significant in either age group (P>.05). The indirect effects via PTSD symptoms were statistically significant among younger people (β=.02; P=.04) and older people (β=.03; P=.01). Social loneliness was not a significant mediator between social media use and suicidal ideation among either age group (P>.05).ConclusionsSocial media may be a “double-edged sword” for psychosocial well-being during the COVID-19 pandemic, and its roles vary across age groups. The mediators identified in this study can be addressed by psychological interventions to prevent severe mental health problems during and after the COVID-19 pandemic. 相似文献
34.
35.
Effect of metabolic acidosis on hyperlipidemia in uremia 总被引:2,自引:0,他引:2
Mak RH 《Pediatric nephrology (Berlin, Germany)》1999,13(9):891-893
Nine patients (aged 18±1 years) on maintenance hemodialysis with metabolic acidosis and hyperlipidemia were studied before
and after 2 weeks of oral sodium bicarbonate (NaHCO3) treatment to correct the acidosis. To control for the effect of additional sodium, they were also studied after 2 weeks
of an equivalent amount of oral sodium chloride (NaCl). Oral NaHCO3 treatment led to significant increases in venous pH, serum bicarbonate, and serum 1,25-dihydroxyvitamin D3 concentrations, but no significant change in total and ionized calcium, phosphate, sodium, potassium, creatinine, blood urea
nitrogen, and intact parathyroid hormone concentrations. Oral NaCl did not change any of the biochemical parameters. Before
treatment of acidosis, these uremic patients had high serum triglycerides, low serum high-density lipoprotein (HDL) cholesterol,
but normal total cholesterol compared with controls. Following 2 weeks of NaHCO3 treatment, there was a significant decrease in the serum concentrations of triglycerides (P<0.01). HDL and total cholesterol did not change. There were no changes in triglycerides, HDL or total cholesterol from baseline
values following 2 weeks of NaCl. Thus treatment of metabolic acidosis ameliorated hypertriglyceridemia but had no effect
on HDL and total cholesterol in patients with uremia on hemodialysis. The underlying mechanism may involve 1,25-dihydroxyvitamin
D3.
Received: 3 August 1998 / Revised: 30 November 1998 / Accepted: 2 December 1998 相似文献
36.
Immunological function were studied in 22 patients with hydatidiform mole and 29 patients with malignant trophoblastic disease before and after treatment; normal pregnant and post-pregnant women served as controls. The only significant abnormality in hydatidiform mole was a low granulocyte chemotaxis before evacuation. In malignant trophoblastic disease the total lymphocyte counts, T-cell counts. B-cell counts, lymphocyte responses to mitogens and serum IgA levels were significantly lower than in normal women 6 wk after pregnancy. In those who responded to chemotherapy, these indices rose to the levels of post-pregnancy controls. An 'immune profile score' based on these indices was found to be a useful prognostic index. All patients with hydatidiform mole who had a score of 7 or less developed malignant trophoblastic disease, while the two patients with malignant trophoblastic disease who died had the lowest scores of the series. 相似文献
37.
SK Roy AM Tomkins SM Akramuzzaman RH Behrens R Haider D Mahalanabis G Fuchs 《Archives of disease in childhood》1997,77(3):196-200
OBJECTIVE: To evaluate the impact of zinc supplementation on the clinical course, stool weight, duration of diarrhoea, changes in serum zinc, and body weight gain of children with acute diarrhoea. DESIGN: Randomised double blind controlled trial. Children were assigned to receive zinc (20 mg elemental zinc per day) containing multivitamins or control group (zinc-free multivitamins) daily in three divided doses for two weeks. SETTING: A diarrhoeal disease hospital in Dhaka, Bangladesh. PATIENTS: 111 children, 3 to 24 months old, below 76% median weight for age of the National Center for Health Statistics standard with acute diarrhoea. Children with severe infection and/or oedema were excluded. MAIN OUTCOME MEASURES: Total diarrhoeal stool output, duration of diarrhoea, rate of weight gain, and changes in serum zinc levels after supplementation. RESULTS: Stool output was 28% less and duration 14% shorter in the zinc supplemented group than placebo (p = 0.06). There were reductions in median total diarrhoeal stool output among zinc supplemented subjects who were shorter (less than 95% height for age), 239 v 326 g/kg (p < 0.04), and who had a lower initial serum zinc (< 14 mmol/l), 279 v 329 g/kg (p < 0.05); a shortening of mean time to recovery occurred (4.7 v 6.2 days, p < 0.04) in those with lower serum zinc. There was an increase in mean serum zinc in the zinc supplemented group (+2.4 v -0.3 mumol/l, p < 0.001) during two weeks of supplementation, and better mean weight gain (120 v 30 g, p < 0.03) at the time of discharge from hospital. CONCLUSIONS: Zinc supplementation is a simple, acceptable, and affordable strategy which should be considered in the management of acute diarrhoea and in prevention of growth faltering in children specially those who are malnourished. 相似文献
38.
Samii A Pal PK Schulzer M Mak E Tsui JK 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》2000,27(1):55-59
BACKGROUND/OBJECTIVE: The incidence of head/neck trauma preceding cervical dystonia (CD) has been reported to be 5-21%. There are few reports comparing the clinical characteristics of patients with and without a history of injury. Our aim was to compare the clinical characteristics of idiopathic CD (CD-I) to those with onset precipitated by trauma (CD-T). METHODS: We evaluated 114 consecutive patients with CD over a 9-month period. All patients were interviewed using a detailed questionnaire and had a neurological examination. Their clinical charts were also reviewed. RESULTS: Fourteen patients (12%) had mild head/neck injury within a year preceding the onset of CD. Between the two groups (CD-I and CD-T), the gender distribution (F:M of 3:2), family history of movement disorders (32% vs. 29%), the prevalence of gestes antagonistes (65% vs. 64%), and response to botulinum toxin were similar. There were non-specific trends, including an earlier age of onset (mean ages 43.3 vs. 37.6), higher prevalence of neck pain (86% vs. 100%), head tremor (67% vs. 79%), and dystonia in other body parts (23% vs. 36%) in CD-T. CONCLUSIONS: CD-I and CD-T are clinically similar. Trauma may be a triggering factor in CD but this was only supported by non-significant trends in its earlier age of onset. 相似文献
39.
40.
用离体大鼠肝脏灌流方法,研究了胆碱酯酶抑制剂CXN的生物转化过程。径HPLC分离纯化及光谱分析,鉴定了CXN的六个脂溶性代谢产物的化学结构。产物Ⅰ为CXN原形,其余均为氧化产物。其中产物Ⅲ尚保留部分抑酶活力,而产物Ⅱ,Ⅴ及Ⅵ对小鼠全脑胆碱酯酶的抑酶活力明显下降。另外还观察到,代谢产物Ⅱ及Ⅴ对小鼠的急性毒性也明显减小。 相似文献