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991.
Purpose Parathyroid carcinoma (PC) is rare and accounts for less than 1% of all cases of primary hyperparathyroidism (PHPT). The definitive histopathologic diagnosis of PC requires unequivocal invasion or metastasis which may be absent at first presentation. As a result, many cases of PC can only be diagnosed retrospectively. Parafibromin is the protein encoded by HRPT2 which is mutated and not expressed in many parathyroid carcinomas. Given that PCs generally weigh more than parathyroid adenomas (PA)s, we hypothesized that amongst large PAs there may be a high incidence of occult PC which could be identified by negative staining for parafibromin. Methodology 57 parathyroid glands weighing greater than 2 grams excised from 1998–2006 were identified from the University of Sydney Endocrine Surgical Database. Two specimens with a histopathologic diagnosis of PC were excluded. Immunohistochemical staining for parafibromin was performed on the remaining 55 PAs. Results Of the 55 specimens stained for parafibromin only one definite negative stain was detected. This case was originally classified as an “atypical adenoma” because it showed nuclear and architectural atypia without unequivocal evidence of invasive growth. In view of the negative staining for parafibromin it therefore probably represents occult carcinoma. There has been no evidence of recurrence or metastasis after 6.5 years. Conclusions Complete loss of staining for parafibromin is very rare in giant parathyroid adenomas suggesting that occult carcinoma is equally rare. As a result routine immunohistochemical staining for parafibromin does not appear to be an effective screening test for carcinoma in large PA without histopathologic features of PC.  相似文献   
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Background: Auricular acupuncture at the relaxation point has been previously shown to be an effective treatment for anxiety in the preoperative setting. The purpose of this prospective, randomized, blinded study was to determine whether auricular acupressure can reduce stress and anxiety during ambulance transport.

Methods: Patients who required ambulance transport secondary to medical conditions were randomized to receive auricular acupressure at the relaxation point (n = 17) or at a sham point (n = 19). A visual analog scale was used to assess state anxiety as well as patient anticipation of hospital medical treatment (estimated waiting period for treatment, anticipated pain during treatment, attitude toward the physicians, and treatment outcomes). These variables were assessed at baseline and on arrival to the hospital.

Results: Patients in the relaxation group reported significantly less anxiety than patients in the sham group on arrival to the hospital (visual analog scale mean +/- SD: 37.6 +/- 20.6 to 12.4 +/- 7.8 mm vs. 42.5 +/- 29.9 to 46.7 +/- 25.9 mm, respectively;P = 0.002). Similarly, patient perception of pain during treatment (mean visual analog scale +/- SD: 32.7 +/- 27.7 to 14.5 +/- 8.1 mm vs. 17.2 +/- 26.1 to 28.8 +/- 21.9 mm, respectively;P = 0.006) and treatment outcomes of their illnesses (mean visual analog scale +/- SD: 46.7 +/- 29.4 to 19.1 +/- 10.4 mm vs. 35.0 +/- 25.7 to 31.5 +/- 20.5 mm, respectively;P = 0.014) were significantly more positive in the relaxation group than in the sham group. No differences were found in the other variables assessed.  相似文献   

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Background: Developmental differences in short- and long-term responses to pain, especially surgical pain, have received minimal attention. The purpose of the present study was to examine postoperative responses in rats of developmental ages paralleling the infant to young adult human.

Methods: The withdrawal threshold to von Frey filament testing and withdrawal latency to hind-paw radiant heating were determined before and for various times after hind-paw incision in rats 2, 4, and 16 weeks of age. Control rats of these ages were observed serially without surgery.

Results: In control animals, younger rats were more sensitive to mechanical stimulation and less sensitive to thermal stimulation. Paw incision resulted in similar changes to both types of stimulation in all age groups, peaking 4 h after surgery. However, the return to normal sensitivity to mechanical stimulation, as measured by return of threshold to 80% of normal, occurred more quickly in 2-week-old than in 4- and 16-week-old animals. In contrast, there was no age difference for time to return to normal sensitivity to thermal stimulation after surgery.  相似文献   

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One of the important steps on the road to becoming expert in a motor skill occurs when the individual can perform the movements in a seemingly effortless and automatic fashion. The authors review two lines of investigations, namely, fMRI and mathematically guided studies of the dynamics of skill acquisition, that suggest that this road to automatic involves two steps: (1) an increasing reliance on the self-regulatory aspects of the motor task, and (2) a minimization of the role of mechanisms based on intentionally directed corrective movements. The interplay between these two mechanisms implies that, at a given skill level, performance decreases whenever intention intervenes. The observation that psychological factors may be as important as mechanical repetition for the development of expertise has important implications for the design of neurorehabilitative strategies.  相似文献   
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