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101.
There is a massive disruption of the global economy and education due to the coronavirus disease-2019 (COVID-19) pandemic. This has posed significant challenges and threats to the academic community, especially in health care where the learning and assessment are patient centered. Though blended learning had its emphasis in the pre-COVID-19 era, innovations are required to meet up to the increased demands on learning and assessment. This article uses an inductive approach and outlines the existing challenges, impact of COVID-19 era, the need for a mindset reframe, and the potential opportunities for innovations that underlie during these challenging times.  相似文献   
102.
Synthesis of a compound with balanced bioactivities against a specific target is always a challenging task. In this study, a novel compound (1) has been synthesized by combination of flurbiprofen and isoniazide and shows ∼2.5 times enhanced acetylcholinesterase (AChE) inhibition activity and ∼1.7 times improved butyrylcholinesterase (BuChE) inhibition activity compared to flurbiprofen and a standard drug (i.e. physostigmine). A comparative AutoDock study has been performed, based on the optimized structure, by the DFT/B3LYP method, which confirmed that compound (1) is more active against AChE and BuChE, with calculated binding energies of −12.9 kcal mol−1 and −9.8 kcal mol−1 respectively as compared to flurbiprofen and an eserine (physostigmine) standard for which the binding energy was calculated to be −10.1 kcal mol−1 and −8.9 kcal mol−1, respectively. A mixed mode of inhibition of AChE and BuChE with compound 1 was confirmed by Lineweaver–Burk plots. AChE and BuChE inhibition activity alongside docking results suggests that compound (1) could be used for treatment of Alzheimer''s disease. Moreover, compound (1) also exhibit better α-chymotrypsin activity compared to flurbiprofen. Furthermore, in vitro and in vivo analysis confirmed that compound (1) exhibit more activity and less toxicity than the parent compounds.

A novel compound (1) shows ∼2.5 and ∼1.7 times enhanced AChE inhibition activity and BuChE inhibition activity respectively compared to flurbiprofen and standard drug (i.e. physostigmine). It has also been confirmed by comparative AutoDock studies.  相似文献   
103.
Laparoscopic Heller cardiomyotomy and Dor fundoplication is the surgical procedure of choice for esophageal achalasia. The aim of our study was to investigate the clinical outcome and safety of laparoscopic Heller–Dor procedure performed by using Hook electrocautery and as a teaching module for advanced laparoscopic surgery. Between January 2005 and December 2010, 25 consecutive patients with achalasia underwent laparoscopic Heller–Dor operation by a single surgeon. All the patients received upper gastrointestinal series (barium swallow), esophagogastroscopy, and esophageal manometry to exclude esophageal carcinoma and to confirm the diagnosis. All the patients were operated by laparoscopic modified Heller myotomy with Dor fundoplication by using hook electrocautery. Among 25 operated patients, 14 were male and 11 were female with a median age of 43 years (range 18–72 years). The mean operative time was 93.3 min (range 50–50 min), the mean operative blood loss was 90 ml (range 40–200 ml), the median time to oral feeding was 2 days (2–4 days), and the median hospital stay was 4 days (4–7 days). There was no conversion to open surgery. Intraoperative mucosal perforation was encountered in three patients and was repaired in all of them by laparoscopic suture. All the patients had an uneventful recovery without postoperative complication and had excellent clinical response (96 %) during follow-up. Laparoscopic Heller–Dor operation using hook electrocautery is safe, inexpensive, and effective treatment for achalasia which is useful for teaching and training surgical residents in advanced laparoscopic surgery.  相似文献   
104.
105.
Objectives. Angiography by selective catheterization is the reference standard for coronary bypass graft patency assessment but carries a risk of serious complications. We have investigated whether 16-slice multidetector spiral computed tomography (MDCT) can substitute for selective angiography. Design. Two to three years after coronary artery bypass grafting, 45 patients with a total of 156 bypasses (100 single and 28 sequential grafts) were examined with both MDCT and conventional selective angiography on the same day. The bypasses were classified as patent, stenotic or occluded. Results. The likelihood ratio for MDCT-detected occlusion was 40, reflecting a fairly high combined sensitivity and specificity. However, 24% of the distal anastomoses could not be evaluated by MDCT, mainly because of respiratory movements, artifacts due to metal clips, and small vessel dimensions. Moreover, seven out of 117 bypasses (6%) deemed evaluable by MDCT were wrongly classified by this method. Conclusions. At present, 16-slice MDCT cannot replace selective angiography for assessment of coronary bypass graft patency since 24% of bypasses could not be evaluated by this method, and an error rate of 6% is unacceptable.  相似文献   
106.
Complete dislocation of the ulnar 4 carpometacarpal joints of the hand (excluding the thumb) is an uncommon injury. Anatomic reduction of the carpometacarpal joint (CMCJ) is essential to maintain function of the hand, and this can often be accomplished by prompt closed reduction and percutaneous Kirschner-wire fixation. The diagnosis is sometimes delayed or missed in the emergency department (ED), and a true lateral radiograph is mandatory in suspected cases. We present a case of dorsal unilateral dislocation of the ulnar 4 CMCJs without associated fracture. The injury was difficult to diagnose because of gross swelling of the hand. We describe a simple clinical test (Indian salutation test) that we found to be very helpful in raising the index of suspicion and hence increasing the likelihood of avoiding any clinical and medicolegal difficulties in such cases. A true lateral radiograph of the wrist confirmed the diagnosis, and prompt closed reduction and percutaneous Kirschner-wire fixation resulted in a good outcome in the case described here.  相似文献   
107.

Objective

To evaluate the efficacy of single oral mega-dose of Vitamin D3 for treatment and prevention of pneumonia in underfive children.

Design

Randomized, double blind, placebo-controlled trial.

Setting

Tertiary-care hospital.

Participants

324 children (of 980 assessed) between 6 mo-5 y age (median (IQR): 12 (7,19.8) mo) with WHO-defined severe pneumonia. Of these, 126 (39%) were vitamin D deficient (serum 25(OH)D <12 ng/mL).

Intervention

100,000 IU of oral cholecalciferol (n= 162) or placebo (n= 162) in single dose, administered at enrolment.

Outcome variables

Primary: Time to resolution of severe pneumonia and proportion of children having recurrence of pneumonia in next 6 months; Secondary: Change in serum levels of 25(OH)D; immunoglobulins IgA, IgG, IgM, and cathelicidin 2 weeks following supplementation; and time taken for overall resolution of illness.

Results

Median (95% CI) time for resolution of severe pneumonia was 30 (29, 31) h in the vitamin D group as compared to 31 (29,33) h in the placebo group [adjusted hazard ratio (95% CI): 1·39 (1·11, 1·76); P=0·005]. The risk of recurrence of pneumonia in next 6 months was comparable in the two groups [placebo: 36/158 (22·8%); vitamin D: 39/156 (25%); RR (95% CI): 1·13 (0·67,1·90); P=0·69]. Proportion of vitamin D deficient children declined from 38% to 4% in the supplementation group, and from 41% to 33% in the placebo group, two weeks after supplementation. There was no significant effect of vitamin D supplementation on serum levels of cathelicidin, IgA and IgG. The time taken for complete recovery from pneumonia, duration of hospitalization, and fever clearance time were comparable for the two groups. No adverse event was noted related to the intervention.

Conclusion

There is no robust evidence of a definite biological benefit, either for therapy or prevention, to suggest a routine megadose supplement of vitamin D3 for under-five children with severe pneumonia.
  相似文献   
108.
109.
110.
Resveratrol (RL), a natural polyphenol, is known for its diverse biological effects against various human cancer cell lines. But low aqueous solubility, poor bioavailability, and stability limit its efficacy against prostate cancer. In this study polymeric nanoparticles encapsulating resveratrol (RLPLGA) were designed and their cytotoxic and mode of apoptotic cells death against prostate cancer cell line (LNCaP) was determined. Nanoparticles were prepared by solvent displacement method and characterized for particle size, TEM, entrapment efficiency, DSC and drug release study. RLPLGA exhibited a significant decrease in cell viability with 50% and 90% inhibitory concentration (IC50 and IC90) of 15.6?±?1.49 and 41.1?±?2.19?μM respectively against the LNCaP cells. This effect was mediated by apoptosis as confirmed by cell cycle arrest at G1-S transition phase, externalization of phosphatidylserine, DNA nicking, loss of mitochondrial membrane potential and reactive oxygen species generation in LNCaP cells. Furthermore, significantly greater cytotoxicity to LNCaP cells was observed with nanoparticles as compared to that of free RL at all tested concentrations. RLPLGA nanoparticles presented no adverse cytotoxic effects on murine macrophages even at 200?μM. Our findings support the potential use of developed resveratrol loaded nanoparticle for the prostate cancer chemoprevention/ chemotherapy with no adverse effect on normal cells.  相似文献   
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