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1.
Neglected tears of the patellar tendon due to loss of active extension remain a difficult therapeutic endeavor. The goals in the approach to this diagnosis include restoration of both structural and functional integrity of the extensor mechanism. A procedure has been developed utilizing Z-shortening of the patellar tendon, Z-lengthening of the quadriceps tendon, and the semitendinosis gracilis as a biologic splint. This technique allows establishment of preoperative goals, including restoration of the muscle-tendon complex in its anatomic position, restoration of quadriceps function, preservation of vascularity of the reconstructed tendon, and splinting of the patellar tendon. This reconstruction allows early mobilization and rehabilitation.  相似文献   
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In this study we consider the process of the clinical encounter, and present exemplars of how assumptions of both clinicians and their patients can shift or transform in the course of a diagnostic interview. We examine the process as it is recalled, and further elaborated, in post-diagnostic interviews as part of a collaborative inquiry during reflections with clinicians and patients in the northeastern United States. Rather than treating assumptions by patients and providers as a fixed attribute of an individual, we treat them as occurring between people within a particular social context, the diagnostic interview. We explore the diagnostic interview as a landscape in which assumptions occur (and can shift), navigate the features of this landscape, and suggest that our examination can best be achieved by the systematic comparison of views of the multiple actors in an experience-near manner. We describe what might be gained by this shift in assumptions and how it can make visible what is at stake for clinician and patient in their local moral worlds—for patients, acknowledgment of social suffering, for clinicians how assumptions are a barrier to engagement with minority patients. It is crucial for clinicians to develop this capacity for reflection when navigating the interactions with patients from different cultures, to recognize and transform assumptions, to notice ‘surprises’, and to elicit what really matters to patients in their care.  相似文献   
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Islet cell carcinomas of the pancreas: a twenty-year experience   总被引:16,自引:0,他引:16  
Unlike its lethal exocrine counterpart, islet cell carcinoma of the pancreas is an indolent neuroendocrine neoplasm. The majority of these tumors are hormonally active. When functioning, a number of clinical syndromes (for example, hyperinsulinism, Zollinger-Ellison and Cushing's syndromes) may be evident. Fifty-eight patients surgically treated between 1965 and 1984 were retrospectively analyzed. The purpose of this study was to determine the distribution of functioning versus nonfunctioning tumors and the response to type of therapy. Mean postoperative follow-up was 7.4 years. Survival and prognostic indices were calculated by the Kaplan-Meier method and compared with log-rank tests. Of the group, 54% had functioning and 46% nonfunctioning tumors. Gastrinomas were the most common functioning tumors encountered (19%). Of interest was the finding that nonfunctioning tumors increased steadily during the last 15 years of the study (25% to 65%). Curative resections were performed in 15 (26%) and noncurative procedures in 43 patients (74%), with an overall operative mortality rate of 3%. Symptomatic improvement was achieved in 90% (curative) and 51% (noncurative). Survival at 3 years was 87% and 66% for the curative and noncurative groups, respectively (p less than 0.1), with an overall 5-year survival of 42%. The absence of hepatic metastases was a major predictor of survival at 3 years (82% vs 56%, p less than 0.05). Survival was statistically better at 3 years in those patients with gastrinomas compared with patients with nonfunctioning tumors (91% vs 58%, p less than 0.05). Although surgical cure is rare, significant long-term palliation may be achieved in a large percentage of patients with an aggressive surgical approach, occasional total gastrectomy, combination chemotherapy, H2 blockade, when indicated, and, most recently, with the new long-acting analogue of somatostatin.  相似文献   
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The buffering capacity of tears collected from contact lens wearers was compared to that from non-contact lens wearers. Three groups of subjects were investigated: 6 subjects not wearing contact lenses, 3 subjects wearing rigid contact lenses, and 3 subjects wearing hydrogel contact lenses. Each of the 12 subjects provided, on 6 separate occasions, 100 microliters of tears. The pH of the tears was measured with a closed chamber, temperature stabilized micro-electrode system firstly on collection and then after titration with acid and base. In all, 28 titration steps across the acid-base spectrum were completed for each subject's tears on each occasion. These tear pH responses to acid-base challenge were compared to that of unbuffered distilled water for the same titration procedure. There was no statistically significant effect of contact lens wear on tear buffering capacity, but considerable inter-subject variability was noted.  相似文献   
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PURPOSE: The change/no-change procedure (J. E. Sussman & A. E. Carney, 1989), which assesses speech discrimination, has been used under the assumption that the number of stimulus presentations does not influence performance. Motivated by the tenets of the multiple looks hypothesis (N. F. Viemeister & G. H. Wakefield, 1991), work by R. F. Holt and A. E. Carney (2005) called this assumption into question (at least for adults): Nonsense syllable discrimination improved with more stimulus presentations. This study investigates the nature of developmental differences and the effects of multiple stimulus presentations in the change/no-change procedure. METHOD: Thirty normal-hearing children, ages 4.0-5.9 years, were tested on 3 consonant-vowel contrasts at various signal-to-noise ratios using combinations of 2 and 4 standard and comparison stimulus repetitions. RESULTS: Although performance fell below that which is predicted by the multiple looks hypothesis in most conditions, discrimination was enhanced with more stimulus repetitions for 1 speech contrast. The relative influence of standard and comparison stimulus repetitions varied across the speech contrasts in a manner different from that of adults. CONCLUSION: Despite providing no additional sensory information, multiple stimulus repetitions enhanced children's discrimination of 1 set of nonsense syllables. The results have implications for models of developmental speech perception and assessing speech discrimination in children.  相似文献   
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The methylxanthine, theobromine (3,7-dimethylxanthine), was tested in mice, to determine whether theobromine could function in vivo as an adenosine receptor antagonist, in keeping with its reported in vitro effects as a blocker of agonist binding to the adenosine A-1 receptor. Theobromine doses, which themselves had no direct effects on spontaneous locomotor activity, completely blocked N6-cyclohexyladenosine-induced suppression of locomotor activity but were without effect on 5'-N-ethylcarboxamide adenosine (NECA)-induced decreases in motor activity. In contrast to the specific antagonism, theobromine blocked the hypothermia induced by both of these adenosine analogs. These results demonstrate that theobromine is an active in vivo adenosine receptor antagonist and that the antagonism of N6-cyclohexyladenosine sensitive systems occurs even though theobromine does not stimulate spontaneous locomotor activity. Thus, the behavioral stimulant effects of methylxanthines may be more related to effects on NECA-sensitive systems, which are not blocked by theobromine. The use of in vivo differences in the effects xanthine may provide a useful tool in the development of compounds to probe the mechanisms of caffeine induced CNS effects.  相似文献   
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Background. Medication adherence impacts healthcare utilization. Pharmacy records are useful to establish fill patterns. Objective. Use pharmacy records to establish medication patterns fill patterns for comparison to healthcare utilization. Methods. Pharmacy records of 175 children with persistent asthma were collected and compared to healthcare utilization. Results. Majority of subjects had significant healthcare utilization, low numbers of rescue medications, and poor controller medication fill rates. Those with more rescue medications had more healthcare utilization and more controller medications. Conclusions. Pharmacy fill patterns demonstrate few rescue and/or controller medication fills. Those with more rescue medications reported increased healthcare utilization despite controller medications.  相似文献   
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