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91.
The objectives of this study were to determine the direction and pattern of flow of irrigating solutions inside simulated root canals with different irrigation needles; and to determine whether different needle designs increase the likelihood of irrigating solution passing through the apical foramen. Two types of needles were compared: a standard needle with a bevel and an open end, and a needle with a side opening and closed rounded tip. Observations of irrigant flow within the canals indicated that the side‐venting needle can be dangerous if the needle gauge is small and it reaches the full length of the canal, since this allowed irrigants to flow into the periapical area. With the standard needle, the fluid did not go beyond the tip of the needle when minimal irrigating pressure was employed. As the size of canal increased, the fluid did not extrude beyond the tip of both needles. However, if the needles bound in the canals, then the fluid was forced away from the needle tip, and the pressure applied to the syringe was directly proportional to the distance the fluid flowed away from the needle tip. Both side‐venting and standard needles can be used for irrigation safely and effectively if a dynamic irrigation technique (moving the needle up and down inside the canals while irrigating) is employed.  相似文献   
92.

BACKGROUND.

Androgen‐deprivation therapy (ADT) causes bone loss and fractures. Guidelines recommend bone density testing before and during ADT to characterize fracture risk. The authors of the current report assessed bone density testing among men who received ADT for ≥ 1 year.

METHODS.

Surveillance, Epidemiology, and End Results/Medicare data were used to identify 28,960 men aged > 65 years with local/regional prostate cancer diagnosed from 2001 to 2007 who were followed through 2009 and who received ≥ 1 year of continuous ADT. Bone density testing was documented in the 18‐month period beginning 6 months before ADT initiation. Logistic regression was used to identify the factors associated with bone density testing.

RESULTS.

Among men who received ≥ 1 year of ADT, 10.2% had a bone density assessment from 6 months before starting ADT through 1 year after. Bone density testing increased over time (14.5% of men who initiated ADT in 2007‐2008 vs 6% of men who initiated ADT in 2001‐2002; odds ratio for 2007‐2008 vs 2001‐2002, 2.29; 95% confidence interval, 1.83‐2.85). Less bone density testing was observed among men aged ≥ 85 years versus men ages 66 to 69 years (odds ratio, 0.76; 95% confidence interval, 0.65‐0.89), among black men versus white men (odds ratio, 0.72; 95% confidence interval, 0.61‐0.86), and among men in areas with lower educational attainment (P < .001). Men who visited a medical oncologist and/or a primary care provider in addition to a urologist had higher odds of testing than men who only consulted a urologist (P < .001).

CONCLUSIONS.

Few men who received ADT for prostate cancer underwent bone density testing, particularly older men, black men, and those living in areas with low educational attainment. Visiting a medical oncologist was associated with increased odds of testing. Interventions are needed to increase bone density testing among men who receive long‐term ADT. Data on bone density testing for nonmilitary populations of prostate cancer survivors in the United States who have received long‐term androgen‐deprivation therapy (ADT) have not been published. The current analysis of Surveillance, Epidemiology, and End Results/Medicare data suggests that few prostate cancer survivors who receive long‐term ADT undergo bone density testing; and several key populations, including African Americans and older men, have considerably lower rates of bone density screening. Cancer 2013. © 2012 American Cancer Society.  相似文献   
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The aim of this study was to investigate the activation characteristics of cerebral cortex in participants with CSP during rhythmic chewing movement. Sixteen right‐handed participants with left (two males: 29·0 ± 8·4 years old, six females: 32·3 ± 4·8 years old) or right (four males: 31·0 ± 6·1 years old, four females: 30·8 ± 4·7 years old) CSP were scanned by functional magnetic resonance imaging during rhythmic chewing. The on‐off sequence of scanning was 30 s of rhythmic chewing and 30 s of rest (off) a total of five times. The results showed that blood oxygen level‐dependent signals in the contralateral (to the CSP) primary sensorimotor cortex increased more than in the ipsilateral primary sensorimotor cortex in participants with both left and right CSP (≤ 0·001). Moreover, the BOLD signal within the right substantia nigra of midbrain, brainstem was more significantly (≤ 0·001) activated than its left counterpart in participants with left CSP, while no activation was observed in those with right CSP. The similar activation of the cerebellum was in participants with right CSP. The inferior parietal lobule, inferior frontal gyrus and left insular cortex were significantly (P ≤ 0·001) activated in participants with CSP. These findings suggest a relationship between hemispheric dominance and CSP in the primary sensorimotor cortex responsible for rhythmic chewing movement. The brainstem and the cerebellum might also play important role in the regulation of CSP. Furthermore, the IFG, IPL and insular may contribute to higher cognitive information processing for participants with CSP.  相似文献   
96.
Chewing‐side preference (CSP) may be associated with temporomandibular disorders. However, little information exists regarding whether CSP will lead to osseous changes of temporomandibular joint (TMJ) in asymptomatic participants. The aim of this study was to investigate the relationship between osseous morphology of TMJ in asymptomatic participants with CSP and without CSP. Of the 121 healthy dentate participants, 35 participants with left CSP, 38 with right CSP and other 48 without CSP were scanned by cone‐beam computed tomography. The dimensions of the reconstructed images of opposing TMJs were compared. Statistical analyses were performed using spss 16.0 software. The results showed that there were no significant differences between the dimensions of bilateral structures of the TMJ (P1 > 0·05) in participants without CSP. However, the posterior–superior, posterior and lateral joint space of the preferred side were smaller than that of the unpreferred side in participants with CSP (P2 < 0·01) and bilateral TMJ in participants without CSP (P3 < 0·01). In addition, width of condylar neck of the unpreferred side both in sagittal and perpendicular to the long axis of condyle views was greater than that of the preferred side in participants with CSP (P2 < 0·01) and bilateral TMJ of participants without CSP (P4 < 0·01). Also, the inclination of articular eminence of the preferred side in view perpendicular to the long axis of condyle was less than that of the unpreferred side (P2 < 0·05). These findings suggest CSP affects osseous morphology of TMJ in asymptomatic participants.  相似文献   
97.
《Vaccine》2018,36(20):2783-2787
BackgroundExtensive clinical investigations are mandatory to evaluate the safety and reactogenicity of vaccines. The recording of common adverse events like injection site soreness or general discomfort derives from individual subjective perceptions. Thermal imaging at the injection site possibly provides a non-subjective and a non-invasive approach to supplement this evaluation.ResultsA protocol for quantified injection-site infrared imaging included 86 participants during a flu vaccine campaign, 40% of whom had a thermal reaction of 1 °C; 25–30% had no thermal response. There was little subjective pain reporting and no clinical correlations were observed except with post-vaccination erythema.Higher responses were linked with advanced age and multiple previous vaccinations.ConclusionEvan if influenza vaccine was only moderately reactogenic, a thermal response was detectable in about 70% of vaccinees, though no relationship to reactogenicity was seen.Infrared imaging might however be a prospective tool for individual studies of vaccine-induced vascular responses.  相似文献   
98.
Local anesthetics are essential medications for the conduction of dermatological procedures. They stop the depolarization of nerve fibers and are divided into two main categories, the amide and ester types. Systemic toxicity with reflex on the central nervous and cardiovascular systems is their most feared adverse reactions, and the anaphylactic reaction is the most concerning one. Although potentially fatal, these events are extremely rare, so local anesthetics are considered safe for use in in-office procedures.  相似文献   
99.
100.
BackgroundDysgeusia is a prevalent qualitative gustatory impairment that may affect food intake and quality of life. The facial (VII), glossopharyngeal (IX), and vagus (X) nerves are the three cranial nerves responsible for sensing taste. Typically, dysgeusia is considered a general term for all taste disorders. In addition, dysgeusia may be a symptom of underlying systemic conditions such as diabetes mellitus, chronic kidney disease, respiratory infections, and nutritional deficiencies. Various subjective and objective diagnostic approaches are available to aid clinicians, each with its own set of benefits and drawbacks.HighlightsTaste impairment can lead to a lack of enjoyment while eating, food aversion, and malnutrition, resulting in a decrease in the quality of life and loss of muscle mass. Therefore, the present review aims to address the probable etiologies, diagnostic aids, and management of dysgeusia. A broad search for studies was conducted using PubMed, Web of Science, Scopus, and Google Scholar. In addition, relevant studies found in the references of the selected articles were also studied.ConclusionOral health care providers should be aware of the possible etiologies of dysgeusia, diagnostic tools, and treatment options. Accurate diagnosis of the cause of taste dysfunction has a significant impact on the management of taste impairment.  相似文献   
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