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91.
Traditionally, it has been assumed that there is only one type of anxiety; recent pharmacologic evidence suggests that there may be several. The psychoanalytic concept of "neurotic" symptoms as depressurizing mechanisms is out of keeping with most evidence now available. Spontaneous or "free-floating" anxiety may be partly biologic and genetic in origin. Anxiety symptoms evoked by specific stimuli behave in part like conditioned responses. Where conditioning theory has failed to propose a plausible unconditioned stimulus for pathologic anxiety, biology, ethology, and psychoanalysis may have been more successful.  相似文献   
92.
In 16 adult dogs the anterior cruciate ligament (ACL) was transected and then reconstructed using freeze dried fascia lata allografts. Eight of the dogs had the intraarticular graft passed through drill holes in the tibia and femur, while in the other eight dogs the graft was passed through a drill hole in the tibia and routed "over-the-top" of the lateral femoral condyle. In all dogs the grafts were then passed deep to the lateral collateral ligament and secondarily secured to the tibia as an extraarticular reconstruction. Specimens from each group underwent histologic study and biomechanical testing on a mechanical testing system at 3, 6, 12, and 24 week intervals. All grafts were found to be intact at sacrifice with no overt evidence of biologic incompatibility. The knees displayed only mild instability to clinical testing without evidence of arthrosis. Histologically, the grafts appeared to function as a collagenous scaffolding for revascularization and fibrovascular creeping substitution. The mean maximum load at failure in the 24 week specimens reached 536.44 N, compared to values of 801.85 N in contralateral knees with an intact ACL.  相似文献   
93.
Of 871 candidates presenting for upper gastrointestinal examinations, 16 met the rigorous criteria established for selecting asymptomatic normal volunteers. Frame-by-frame evaluation of their videorecorded pharyngeal swallow confirmed many observations made previously utilizing cine recording at much higher radiation dosages. In addition, new observations were made: the nasopharynx may not occlude until the bolus is entirely within the pharynx; air mixes with the bolus if the swallow is an "open" type; the epiglottis always inverts in normal individuals regardless of the type of swallow ("open," air filled oro-and hypopharynx into which the swallowed bolus is dropped; "closed," airless oropharynx into which the swallowed bolus is pushed by a continuous peristaltic drive of the tongue and palate, thus reconstituting the pharyngeal space); laryngeal descent may aid in stripping the bolus from the pharynx; the vestibule may not completely close during the swallow and the larynx can still be impervious to the bolus; the peristaltic wave does not begin until the bolus has breeched the cricopharyngeus; the cricopharyngeus may be seen frequently in normal individuals, but does not delay the passage of the bolus; asymmetric flow of the bolus around the larynx is common and may not be the result of epiglottic tilt or head positioning.  相似文献   
94.
Systematic esophageal evaluation of patients with noncardiac chest pain   总被引:2,自引:0,他引:2  
We prospectively studied 73 patients with angina-like chest pain severe enough to warrant admission to a coronary care unit over a five-month period. Thirty-four patients (47%) were found to have coronary artery disease as the cause of their symptoms, based on exercise testing, stress radionuclide imaging, or cardiac catheterization. The remaining 39 patients had normal cardiac findings and then underwent videoesophagography, radionuclide esophageal transit study, and esophageal manometry. Thirty-three of the 39 underwent acid perfusion testing (modified Bernstein's test). The findings at esophageal manometry were abnormal in 29 (74%) of 39. Manometric diagnoses were "nutcracker esophagus" in 17 (59%), nonspecific esophageal motility disorders in nine (31%), diffuse esophageal spasm in two (7%), and achalasia in one (3%). Bernstein's test reproduced symptoms in only 12%. The sensitivity of videoesophagography in detecting esophageal motility disorders was 66%, and that of radionuclide esophageal transit was 79%. The positive predictive values were 86% and 85%, respectively.  相似文献   
95.
Front of pack food labels (FOPLs) provide accessible nutritional information to guide consumer choice. Using an online experiment with a large representative British sample, we aimed to examine whether FOPLs improve participants’ ability to identify the healthiness of foods and drinks. The primary aim was to compare ability to rank between FOPL groups and a no label control. Adults (≥18 years), recruited from the NatCen panel, were randomised to one of five experimental groups (Multiple Traffic Light, MTL; Nutri-Score, N-S; Warning Label, WL; Positive Choice tick, PC; no label control). Stratification variables were year of recruitment to panel, sex, age, government office region, and household income. Packaging images were created for three versions, varying in healthiness, of six food and drink products (pizza, drinks, cakes, crisps, yoghurts, breakfast cereals). Participants were asked to rank the three product images in order of healthiness. Ranking was completed on a single occasion and comprised a baseline measure (with no FOPL), and a follow-up measure including the FOPL as per each participant’s experimental group. The primary outcome was the ability to accurately rank product healthiness (all products ranked correctly vs. any incorrect). In 2020, 4504 participants had complete data and were included in the analysis. The probability of correct ranking at follow-up, and improving between baseline and follow-up, was significantly greater across all products for the N-S, MTL and WL groups, compared to control. This was seen for only some of the products for the PC group. The largest effects were seen for N-S, followed by MTL. These analyses were adjusted for stratification variables, ethnicity, education, household composition, food shopping responsibility, and current FOPL use. Exploratory analyses showed a tendency for participants with higher compared to lower education to rank products more accurately. Conclusions: All FOPLs were effective at improving participants’ ability to correctly rank products according to healthiness in this large representative British sample, with the largest effects seen for N-S, followed by MTL.  相似文献   
96.
ObjectiveDespite improved mortality rates after burn injury, many patients face significant long-term physical and psychosocial disabilities. We aimed to determine whether commonly used mortality prognostication scores predict long-term, health-related quality of life after burn injury. By doing so, we might add evidence to support goals of care discussions and facilitate shared decision-making efforts in the hours and days after a life-changing injury.MethodsWe used the multicenter National Institute of Disability, Independent Living and Rehabilitation Research Burn Model System database (1994–2019) to analyze SF-12 physical (PCS) and mental component (MCS) scores among survivors one year after major burn injury. Ninety percent of the observations were randomly assigned to a model development dataset. Multilevel, mixed-effects, linear regression models determined the relationship between revised Baux and Ryan Scores and SF-12 measures. Additionally, we tested a model with disaggregated independent and other covariates easily obtained around the time of index admission: age, sex, race, burn size, inhalation injury. Residuals from the remaining 10% of observations in the validation dataset were examined.ResultsThe analysis included 1606 respondents (median age 42 years, IQR 28–53 years; 70% male). Median burn size was 16% TBSA (IQR 6–30) and 13% of respondents sustained inhalation injury. Higher revised Baux and Ryan Scores and age, burn size, and inhalation injury were significantly correlated with lower PCS, but were not correlated with MCS. Female sex, black race, burn size, and inhalation injury correlated with lower MCS. All models poorly explained the variance in SF-12 scores (adjusted r2 0.01–0.12).ConclusionHigher revised Baux and Ryan Scores negatively correlated with long-term physical health, but not mental health, after burn injury. Regardless, the models poorly explained the variance in SF-12 scores one year after injury. More accurate models are needed to predict long-term, health-related quality of life and support shared decision-making during acute burn care.  相似文献   
97.
Between 2013 and 2019, there was an increase in the consent rate for organ donation in the UK from 61% to 67%, but this remains lower than many European countries. Data on all family approaches (16,896) for donation in UK intensive care units or emergency departments between April 2014 and March 2019 were extracted from the referral records and the national potential donor audit held by NHS Blood and Transplant. Complete data were available for 15,465 approaches. Consent for donation after brain death was significantly higher than for donation after circulatory death, 70% (4260/6060) vs. 60% (5645/9405), (OR 1.58, 95%CI 1.47–1.69). Patient ethnicity, religious beliefs, sex and socio-economic status, and knowledge of a patient's donation decision were strongly associated with consent (p < 0.001). These factors should be addressed by medium- to long-term strategies to increase community interventions, encouraging family discussions regarding donation decisions and increasing registration on the organ donor register. The most readily modifiable factor was the involvement of an organ donation specialist nurse at all stages leading up to the approach and the approach itself. If no organ donation specialist nurse was present, the consent rates were significantly lower for donation after brain death (OR 0.31, 95%CI 0.23–0.42) and donation after cardiac death (OR 0.26, 95%CI 0.22–0.31) compared with if a collaborative approach was employed. Other modifiable factors that significantly improved consent rates included less than six relatives present during the formal approach; the time from intensive care unit admission to the approach (less for donation after brain death, more for donation after cardiac death); family not witnessing neurological death tests; and the relationship of the primary consenter to the patient. These modifiable factors should be taken into consideration when planning the best bespoke approach to an individual family to discuss the option of organ donation as an end-of-life care choice for the patient.  相似文献   
98.
Archives of Sexual Behavior - Changes to how gay, bisexual, and other men who have sex with men (GBM) connect with each other and with their communities have implications for HIV prevention. Social...  相似文献   
99.
Archives of Sexual Behavior - Although men who have sex with men (MSM) within rural communities are disproportionately impacted by HIV, limited HIV research and programmatic resources are directed...  相似文献   
100.
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