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41.
Malaysia has one of the highest total numbers of COVID-19 infections amongst the Southeast Asian nations, which led to the enforcements of the Malaysian “Movement Control Order” to prohibit disease transmission. The overwhelming increasing amount of infections has led to a major strain on major healthcare services. This leads to shortages in hospital beds, ventilators and critical personnel protective equipment. This article focuses on the critical adaptations from a general surgery department in Malaysia which is part of a Malaysian tertiary hospital that treats COVID-19 cases. The core highlights of these strategies enforced during this pandemic are: (1) surgery ward and clinic decongestions; (2) deferment of elective surgeries; (3) restructuring of medical personnel work force; (4) utilization of online applications for tele-communication; (5) operating room (OR) adjustments and patient screening; and (6)continuing medical education and updating practices in context to COVID-19. These adaptations were important for the continuation of emergency surgery services, preventing transmission of COVID-19 amongst healthcare workers and optimization of medical personnel work force in times of a global pandemic. In addition, an early analysis on the impact of COVID-19 pandemic and lockdown measures in Malaysia towards the reduction in total number of elective/emergent/trauma surgeries performed is described in this article.  相似文献   
42.

Purpose

Maintaining target hemoglobin (Hb) with minimal variability is a challenge in hemodialysis (HD) patients. The aim of this study is to compare the long- and short-acting erythropoietin-stimulating agents such as Aranesp and Eprex in achieving these targets.

Methods

Randomized, prospective, open-labeled study of 24 weeks includes stable patients on HD >3 months, age >18 years, and on Eprex for >3 months. Patients were randomized into two groups: A-(Aranesp group):HD patients on Eprex Q TIW or BIW were converted to Aranesp Q weekly, by using the conversion factor of 200:1 and those on Eprex Q weekly to Aranesp Q 2 weeks; B-(Eprex group):patients continued on Eprex treatment. Hemoglobin target was set at (105–125 g/l). Primary end points were percentage of patients achieving target Hb, hemoglobin variability, and number of dose changes in each group.

Results

This study consisted of 139 HD patients: 72 in the Aranesp and 67 in the Eprex—mean (SD) age 54 (16.2) years, 77 (55 %) males. About 46 % were diabetic. Target Hb achieved in 64.8 % of the Aranesp and 59.7 % in the Eprex (p = 0.006). Hb variability was less frequent in the Aranesp group (p = 0.2). Mean number of dose changes was 1.3 (0.87) in the Aranesp and 1.9 (1.2) in the Eprex (p < 0.001). There was 1 vascular access thrombosis in the Aranesp and 8 in the Eprex (p < 0.001). There was no difference in hospitalization and death number between the 2 groups.

Conclusions

Aranesp Q weekly or every 2 weeks is more efficient in achieving target Hb, with less dose changes and minor vascular access complications.  相似文献   
43.
Angiogenesis is a physiological process which describes the development of new blood vessels from the existing vessels. It is a common and the most important process in the formation and development of blood vessels, so it is supportive in the healing of wounds and granulation of tissues. The different assays for the evaluation of angiogenesis have been described with distinct advantages and some limitations. In order to develop angiogenic and antiangiogenic techniques, continuous efforts have been resulted to give animal models for more quantitative analysis of angiogenesis. Most of the studies on angiogenic inducers and inhibitors rely on various models, both in vitro, in vivo and in ova, as indicators of efficacy. The angiogenesis assays are very much helpful to test efficacy of both pro- and anti- angiogenic agents. The development of non-invasive procedures for quantification of angiogenesis will facilitate this process significantly. The main objective of this review article is to focus on the novel and existing methods of angiogenesis and their quantification techniques. These findings will be helpful to establish the most convenient methods for the detection, quantification of angiogenesis and to develop a novel, well tolerated and cost effective anti-angiogenic treatment in the near future.KEY WORDS: Angiogenesis, angiogenesis assays, quantification techniques  相似文献   
44.
TiO2 is a compound of great importance due to its remarkable catalytic and distinctive semiconducting properties. It is also a chemically stable, non-toxic and biocompatible material. Nano TiO2 is strong oxidizing agent with a large surface area and, hence, high photo-catalytic activities. With low production cost and a high dielectric constant, it is an inexpensive material. It can be prepared by diverse procedures such as solution and gas phase procedures. Nowadays, TiO2 is being used frequently for photo degradation of organic molecules and water splitting for hydrogen generation. Most important applications include purification, disinfection of waste water, self-cleaning coatings for buildings in urban areas and the production of the green currency of energy (hydrogen) by splitting water. The review describes the advances in the syntheses, properties and applications of TiO2 nano structures. Besides, efforts are also made to discuss the working mechanism and future challenges and perspectives.

TiO2 is a compound of great importance due to its remarkable catalytic and distinctive semiconducting properties.  相似文献   
45.
Poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] were prepared and characterized by UV-Vis, FTIR, AFM, and zetasizer analysis. Investigation of the potential of the synthesized poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] for detection of nicotine is the main focus of the current study. P(2VP-MMA)-AuNPs were coated on a glassy carbon electrode (GCE) for electrochemical detection of nicotine by cyclic voltammetry. The effect of molar mass of individual P2VP blocks and total molar mass of the block copolymer is evaluated in the context of an enhanced electrochemical response of the modified GCE for its sensing ability of nicotine in both aqueous and organic media. The electrochemical detection of nicotine is significantly enhanced by modification of the GCE with P(2VP-MMA)-AuNPs.

Poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] are employed for enhancement of electrochemical response of glassy carbon electrode for nicotine.  相似文献   
46.
The incidence of most cancers increases with age. Cancer is the second most common cause of death in older adults after cardiovascular disease. Many common cancers in older adults can be prevented from occurring or can be identified at an early stage and treated effectively. The prevention and identification of cancer in its early stages, in an attempt to reduce discomfort and disability associated with advanced cancer and cancer treatment, is also a priority. Overscreening for cancer in older adults can lead to unnecessary diagnostic testing and unnecessary treatment. Both older adults and their healthcare providers need guidance on the appropriate use of cancer prevention and screening interventions. This first of a two-part review addresses special considerations regarding cancer prevention for adults aged 65 and older. Screening decisions and the impact of limited life expectancy and an older adult's ability to tolerate cancer treatment are also addressed. Guidance is provided regarding the prevention and early identification of lung, colorectal, bladder, and kidney cancer in older adults. The prevention of breast, prostate, and female urogenital cancers are addressed in Part 2. J Am Geriatr Soc 68:2399–2406, 2020.  相似文献   
47.

Background and purpose

Metal artifact reduction sequence (MARS) MRI and ultrasound scanning (USS) can both be used to detect pseudotumors, abductor muscle atrophy, and tendinous pathology in patients with painful metal-on-metal (MOM) hip arthroplasty. We wanted to determine the diagnostic test characteristics of USS using MARS MRI as a reference for detection of pseudotumors and muscle atrophy.

Patients and methods

We performed a prospective cohort study to compare MARS MRI and USS findings in 19 consecutive patients with unilateral MOM hips. Protocolized USS was performed by consultant musculoskeletal radiologists who were blinded regarding clinical details. Reports were independently compared with MARS MRI, the imaging gold standard, to calculate predictive values.

Results

The prevalence of pseudotumors on MARS MRI was 68% (95% CI: 43–87) and on USS it was 53% (CI: 29–76). The sensitivity of USS in detecting pseudotumors was 69% (CI 39–91) and the specificity was 83% (CI: 36–97). The sensitivity of detection of abductor muscle atrophy was 47% (CI: 24–71). In addition, joint effusion was detected in 10 cases by USS and none were seen by MARS MRI.

Interpretation

We found a poor agreement between USS and MARS MRI. USS was inferior to MARS MRI for detection of pseudotumors and muscle atrophy, but it was superior for detection of joint effusion and tendinous pathologies. MARS MRI is more advantageous than USS for practical reasons, including preoperative planning and longitudinal comparison.Approximately 1.5 million metal-on-metal (MOM) hip arthroplasties have been implanted worldwide since 1996 (FDA 2012). A high early failure rate for these prostheses has recently been demonstrated (Smith et al. 2012). The pattern of failure appears to differ from other hip arthroplasty types, with adverse reactions to wear-related metal debris being a prominent feature (Pandit et al. 2008, Kwon et al. 2011). These solid or cystic lesions have been termed pseudotumors (Pandit et al. 2008). A wide spectrum of adverse tissue reactions have been described. Histologically, using their pseudocapsules, these have been termed aseptic lymphocytic vasculitis-associated lesions (ALVALs) (Willert et al. 2005).Health regulatory guidelines recommend investigation with cross-sectional imaging, using either metal artifact reduction sequence (MARS) MRI or ultrasound scanning (USS), to evaluate the periprosthetic soft tissues. A number of advantages and disadvantages have been reported (Sabah et al. 2011, Liddle et al. 2013). The high-resolution capability of USS allows detailed imaging of solid or cystic extra-articular lesions and also detection of muscle atrophy (Sofka et al. 2004), joint effusions, gluteal tendon avulsion, and iliopsoas or trochanteric bursitis (Long et al. 2012). USS is also commonly used during guided anesthetic injection or fluid aspiration.

Table 1.

A comparison of the advantages and disadvantages of MARS MRI and ultrasound imaging of metal-on-metal hips
UltrasoundMARS MRI
1) Clinical evaluationNo metal artifact produced.
Operator-dependent; requires an experienced musculoskeletal sonographer.
Must be reported at the time of scanning.
Not operator dependant.
Can be reported later.
Images can be sent off-site for specialist opinion.
Useful during preoperative planning for revision arthroplasty (Hart et al. 2012).
 a) PseudotumorsExcellent at visualizing extra-articular fluid collections (including within the iliopsoas and trochanteric bursa).
Can differentiate easily between solid and fluid composition.
Deep posterior lesions and small lesions can often be missed (Nishii et al. 2012).
High sensitivity for the detection of solid and cystic soft tissue lesions including both small lesions and posterior lesions (Hart et al. 2012, Liddle et al. 2013).
 b) MusclesDual-view function can be used to simultaneously compare muscles on contralateral sides.
Currently not validated to assess muscle atrophy of the hip rotator cuff.
T1-weighted images excellent for assessment of the degree of muscle atrophy (Bal and Lowe 2008, Sabah et al. 2011).
Complete cross-sectional imaging allows easy comparison with the contralateral side.
Images can be accurately compared over time.
 c) Other pathologySensitive for joint effusion diagnosis (Foldes et al. 1992).
Can visualize the iliopsoas and gluteal tendons in detail.
Can be used to detect tendon avulsion of hip abductor muscles (Garcia et al. 2010).
Dynamic imaging is possible.
Hands-on examination can help localize pathology.
Sensitive modality for the assessment of gluteal tendon avulsion.
Other pathology can be identified, including metastatic disease, fractures, and muscle and bone marrow edema.
Metal artifact may obscure effusions and tendons directly adjacent to the implant.
2) Patient acceptabilitySafe, with no major contraindications (can be used on patients with cardiac pacemaker implants).
No problems with claustrophobia.
Non-invasive.
Invasive when used for guided fluid aspiration or injection.
Enclosed space often unacceptable to patients with claustrophobia.
Contraindicated in patients with incompatible metallic implants (e.g. a cardiac pacemaker).
3) GeneralRelatively low costs.
Compact equipment requires minimal space.
Often readily accessible in smaller healthcare trusts.
Relatively expensive.
The bulky equipment requires a relatively large space.
May not be accessible in smaller healthcare trusts.
Open in a separate windowThere is debate as to whether USS or MARS MRI should be used as the initial imaging modality for detection of pseudotumors around MOM hips. There have not been any published studies directly comparing the diagnostic performance of the 2 modalities, and guidelines leave the use of either investigation at the discretion of the surgeon.We determined the sensitivity, specificity, and predictive values of USS using MARS MRI as a reference for the detection of pseudotumors and muscle atrophy.  相似文献   
48.
Compliance to dietary recommendations among hypertensive people is a major health care issue. Non-compliance can nullify the effects of even the most scientific and optimum treatment plan. The main aim of this study was to determine the frequency and predictors of non-adherence in our region. We also investigated the possible factors based on patient opinions that could increase compliance. A sample of 400 adult patients, diagnosed with hypertension for at least 3 years, who visited Civil Hospital during the time period April–June 2013 were included in this cross sectional study. Patient data and opinions were collected by two trained interviewers using a pre-coded questionnaire. Compliance was assessed based on patients self report. More than three quarters (n = 310, 77.5 %) of the hypertensive patients were non-compliant. More than one social gathering in a week, peer-influence, no friends to follow the recommended diet plan and lack of believe regarding diet as an effective measure to control blood pressure were found to be the significant predictors of non-compliance (P values <0.0001). Counseling was thought to be the most effective way by the patients to increase adherence. Non-compliance to dietary recommendations is a major problem prevalent especially in Pakistan. There is an urgent need for doctors and nurses to counsel their patients effectively to prevent future morbidities and mortalities because of non-compliance.  相似文献   
49.
In this paper, we study double cascade dressed optical metal oxide semiconductor field-effect transistor (MOSFET) by exploiting enhancement and suppression for mixed-phase (hexagonal + tetragonal) of Eu3+:YPO4 and different phases (hexagonal + tetragonal and pure tetragonal) of Pr3+:YPO4 crystals. We report variation of fine structure energy levels in different doped ions (Eu3+ and Pr3+) in the host YPO crystal. We compared multi-level energy transition from a single dressing laser with single level energy transition from double cascade dressing lasers. Gate delay facilitates multi-energy level dressed transition and is modeled through a Hamiltonian. Based on the results of double cascade dressing, we have realized MOSFET for logic gates (inverter and logic not and gate) with a switching contrast of about 92% using a mixed phase of Pr3+:YPO4.

By changing different parameters of single and double lasers, we observed the dressed energy level transition from single to multi-level with a single laser. Each sample responded based on their ions'' structure and phase symmetry in the host YPO crystal.  相似文献   
50.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Endophytic microbes residing inside the tissues of plants play a significant role to enhance the growth and...  相似文献   
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