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61.
This study examined the role of pain catastrophizing, fear of movement and depression as determinants of repetition-induced summation of activity-related pain. The sample consisted of 90 (44 women and 46 men) work-disabled individuals with chronic low back pain. Participants were asked to lift a series of 18 canisters that varied according to weight (2.9 kg, 3.4 kg, 3.9 kg) and distance from the body. The canisters were arranged in a 3 × 6 matrix and the weights were distributed such that each ‘column’ of three canisters was equated in terms of physical demands. Participants rated their pain after each lift, and in a separate trial, estimated the weight of each canister. Mean activity-related pain ratings were computed for each Column of the task. An index of repetition-induced summation of pain was derived as the change in pain ratings across the six ‘columns’ of the task. Pain catastrophizing, fear of movement and depression were significantly correlated with condition-related pain (e.g., MPQ) and activity-related pain ratings. Women rated their pain as more intense than men, and estimated weights to be greater than men. A repetition-induced summation of pain effect was observed where pain ratings increased as participants lifted successive canisters. Fear of movement, but not pain catastrophizing or depression, was associated with greater repetition-induced summation of pain. The findings point to possible neurophysiological mechanisms that could help explain why fear of pain is a robust predictor of pain-related disability. Mechanisms of repetition-induced summation of activity-related pain are discussed.  相似文献   
62.
The authors report 1 clinical case of pelvic endometriosis. The urinary symptoms and the radiological appearance of endometriosis with compression of the ureter are non specific. The diagnosis was established by histological examination of the resection specimen. The authors describe the therapeutic approach based on radical surgery designed to eradicate the endometriosis, while remaining as conservative as possible in order to allow subsequent pregnancy, and the place of urological surgery combined with medical treatment with LHRH analogue.  相似文献   
63.
Several studies have shown that a prolonged Ca(2+) elevation follows a glutamate-mediated excitotoxic insult in cultured neurons, and may be associated with impending cell death. Recently, we showed that the prolonged Ca(2+) elevation that emerges as neurons age in culture is specifically linked to an age-related increase in excitotoxic vulnerability. However, the multiple sources of Ca(2+) that contribute to Ca(2+) elevation during and after glutamate exposure are not well understood. Here, we examined the Ca(2+) sources of the age-related prolonged Ca(2+) elevation in cultured hippocampal neurons. Studies with caffeine showed that the ryanodine receptor-dependent releasable pool of Ca(2+) from intracellular stores was similar in older and younger neurons. Thapsigargin, which inhibits intracellular store refilling, did not mimic the age-related prolonged Ca(2+) elevation and, in fact, partially reduced it. Ryanodine, which blocks Ca(2+)-induced Ca(2+)-release (CICR) from stores, completely blocked the age-related prolonged Ca(2+) elevation following glutamate exposure but did not alter maximal Ca(2+) elevation during the glutamate exposure. Thus, we conclude that sustained CICR plays a selective and key role in generating the lethal, age-related, prolonged Ca(2+) elevation, and is the likely mechanism underlying age-related, enhanced vulnerability to excitotoxicity in neurons.  相似文献   
64.
Biomechanics and neuropathology of adult and paediatric head injury   总被引:8,自引:0,他引:8  
The objective of this study was to understand the biomechanics in age-related primary traumatic brain injuries (TBI) causing initial severity and secondary progressive damage and to develop strategy reducing TBI outcome variability using biomechanical reconstruction to identify types of causal mechanisms prior to clinical trials of neuro-protective treatment. The methods included the explanation of TBI biomechanics and physiopathological mechanisms from dual perspectives of neurosurgery and biomechanical engineering. Scaling of tolerances for skull failure and brain injuries in infants, children and adults are developed. Diagnostic assumptions without biomechanical considerations are critiqued. Methods for retrospective TBI reconstruction for prevention are summarized. Mechanisms of TBI are based on the differences between the mechanical properties of the head and neck related to age. Skull fracture levels correlate with increasing cranial bone thickness and in the development of the cranial sutures in infants and in adults. Head injury tolerance levels at three age categories for cerebral concussion, skull fracture and three grades of diffuse axonal injuries (DAI) are presented. Brain mass correlates inversely for TBI caused by angular head motions and locations of injurious stresses are predictable by centripetal theory. Improved quantitative diagnosis of TBI type and severity levels depend primarily on age and biomechanical mechanisms. Reconstruction of the biomechanics is feasible and enables quantitative stratification of TBI severity. Experimental treatment has succeeded in preventing progressive damage in animal TBI models. In humans this has failed, because the animal model received biomechanically controlled TBI and humans did not. Clinical similarities of human TBI patients do not necessarily predict equivalent biomechanics because such trauma can be produced in various ways. We recommend 'reverse engineering' for in-depth reconstruction of the TBI injury mechanism for qualitative diagnoses and reduction of outcome variability.  相似文献   
65.

Background  

One of the most thoroughly studied systems in relation to its prognostic relevance in patients with breast cancer, is the plasminogen activation system that comprises of, among others, the urokinase Plasminogen Activator (uPA) and its main inhibitor, the Plasminogen Activator Inhibitor-1 (PAI-1). In this study, we investigated the prognostic value of uPA and PAI-1 at the mRNA level in lymph node- and hormone receptor-positive breast cancer.  相似文献   
66.
Mok E  Paquette M  Thibault L 《Appetite》2000,34(3):313-325
Macronutrient intakes, 2h and 12h, following administration of a selective 5-HT3 agonist, quipazine, N methyl, dimaleate (QUIPAZINE; 2.5, 5.0 and 7.5 mg/kg, i.p.) at dark onset were examined in three groups of adult male and female Wistar rats fed different sources of the three macronutrients: Group 1 (casein, corn starch, safflower oil), Group 2 (egg protein, corn starch/sucrose, lard) and Group S (casein hydrolysate, maltose dextrin, butter). QUIPAZINE decreased total food intake only in female rats from Group 1 (2 h) at a dose of 7.5 mg/kg and Group 2 (2h and 12h) with doses of 2.5 and 7.5 mg/kg. Intakes from corn starch and corn starch/sucrose diet (12h) were reduced in male and female rats, respectively, with doses of 2.5 and 7.5 mg/kg of QUIPAZINE. In conclusion, when provided with different sources of the three macronutrients, quipazine injection reduces specifically carbohydrate ingestion from corn starch-containing diets in male and female rats. Thus, the nature of the macronutrient source is of major importance to assess the effect of a drug on nutrient-specific selection.  相似文献   
67.
To investigate admissions from nursing homes to a medical intensive care unit (ICU), the authors detailed the major interventions, costs, and outcomes for such patients (n = 67) over a 3-year period and then compared them with those for ICU patients receiving home care or visiting nurse services (240 patients) before admission and all others older than 65 years of age (949 patients). These three groups comprised 37% of total ICU admissions. In contrast to younger patients admitted primarily with acute ischemic heart disease, nursing home patients were more likely to be admitted with cardiopulmonary arrest, infection, and gastrointestinal bleeding. Major interventions of intubation and mechanical ventilation were most frequent for nursing home patients, but total hospital charges differed little among the groups. In-hospital mortality for the nursing home group (28%) was significantly higher than for the home care group (7%) and others older than 65 years of age (7%). Cumulative mortality for the nursing home group reached 66% by 8 months, versus 32% and 26% in the other groups, respectively.  相似文献   
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