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41.
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   
42.

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   
43.
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   
44.
45.
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   
46.
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   
47.
Apigenin is an edible plant‐derived flavonoid that has been reported as an anticancer agent in several experimental and biological studies. It exhibits cell growth arrest and apoptosis in different types of tumors such as breast, lung, liver, skin, blood, colon, prostate, pancreatic, cervical, oral, and stomach, by modulating several signaling pathways. Apigenin induces apoptosis by the activation of extrinsic caspase‐dependent pathway by upregulating the mRNA expressions of caspase‐3, caspase‐8, and TNF‐α. It induces intrinsic apoptosis pathway as evidenced by the induction of cytochrome c, Bax, and caspase‐3, while caspase‐8, TNF‐α, and B‐cell lymphoma 2 levels remained unchanged in human prostate cancer PC‐3 cells. Apigenin treatment leads to significant downregulation of matrix metallopeptidases‐2, ?9, Snail, and Slug, suppressing invasion. The expressions of NF‐κB p105/p50, PI3K, Akt, and the phosphorylation of p‐Akt decreases after treatment with apigenin. However, apigenin‐mediated treatment significantly reduces pluripotency marker Oct3/4 protein expression which might be associated with the downregulation of PI3K/Akt/NF‐κB signaling.  相似文献   
48.
ObjectivesDengue remains hyperendemic in Malaysia despite extensive vector control activities. With dynamic changes in land use, urbanisation and population movement, periodic updates on dengue transmission patterns are crucial to ensure the implementation of effective control strategies. We sought to assess shifts in the trends and spatial patterns of dengue in Kelantan, a north-eastern state of Malaysia (5°15’N 102°0’E).MethodsThis study incorporated data from the national dengue monitoring system (eDengue system). Confirmed dengue cases registered in Kelantan with disease onset between January 1, 2016 and December 31, 2018 were included in the study. Yearly changes in dengue incidence were mapped by using ArcGIS. Hotspot analysis was performed using Getis-Ord Gi to track changes in the trends of dengue spatial clustering.ResultsA total of 10 645 dengue cases were recorded in Kelantan between 2016 and 2018, with an average of 10 dengue cases reported daily (standard deviation, 11.02). Areas with persistently high dengue incidence were seen mainly in the coastal region for the 3-year period. However, the hotspots shifted over time with a gradual dispersion of hotspots to their adjacent districts.ConclusionsA notable shift in the spatial patterns of dengue was observed. We were able to glimpse the shift of dengue from an urban to peri-urban disease with the possible effect of a state-wide population movement that affects dengue transmission.  相似文献   
49.
50.
Soil improvement via MICP (microbially induced carbonate precipitation) technologies has recently received widespread attention in the geoenvironmental and geotechnical fields. The durability of MICP-treated samples remains a critical concern in this novel method. In this work, fiber (jute)-reinforced MICP-treated samples were investigated to evaluate their durability under exposure to distilled water (DW) and artificial seawater (ASW), so as to advance the understanding of long-term performance mimicking real field conditions, along with improvement of the MICP-treated samples for use in coastal erosion protection. Primarily, the results showed that the addition of fiber (jute) improved the durability of the MICP-treated samples by more than 50%. Results also showed that the wet–dry (WD) cyclic process resulted in adverse effects on the mechanical and physical characteristics of fiber-reinforced MICP-treated samples in both DW and ASW. The breakdown of calcium carbonates and bonding effects in between the sand particles was discovered to be involved in the deterioration of MICP samples caused by WD cycles, and this occurs in two stages. The findings of this study would be extremely beneficial to extend the insight and understanding of improvement and durability responses for significant and effective MICP treatments and/or re-treatments.  相似文献   
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