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91.
The Postconcussive Symptom Questionnaire (PCSQ) was developed to assess the symptoms associated with the controversial diagnosis of postconcussion syndrome. We examined item endorsement on the PCSQ in two groups. The first group was made up of individuals diagnosed with moderate to severe traumatic brain injury. The second group was made up of individuals meeting criteria for mild traumatic brain injury who exhibited no evidence of neurological injury. In addition, they demonstrated poor effort during neuropsychological examination. Significant differences in item endorsement were found the majority of individual items as well as on the PCSQ indices. The poor effort mild traumatic brain injury group consistently reported more symptoms with greater severity. The results raise further questions about the validity of postconcussion symptoms.  相似文献   
92.
Traumatic injuries of the distal radioulnar joint (DRUJ) may give rise to complex wrist pathologies. Substantial ongoing disability can arise should these injuries go unrecognized resulting in sub-optimal treatment and lack of appropriate rehabilitation. Injuries of the DRUJ may occur in isolation but more commonly are found with a fracture of the radius. These challenging DRUJ injuries may be simple or complex (irreducible or severe instability), acute or chronic. An adequate knowledge of the stabilizers of the DRUJ is essential in understanding treatment options. Traumatic instability of the DRUJ is reviewed and the anatomy and stabilizing factors are discussed. An algorithm to guide selection of treatment options in complex cases is presented.  相似文献   
93.

Purpose:

Shoulder pain is a major musculoskeletal and economic concern in industrialized countries, with the rate of surgical failure reportedly higher in patients injured at work. The purposes of this study were (1) to examine the prevalence of identifiable causes of rotator cuff surgery failure and (2) to examine the relationship among the existence of these causes and outcome scores, patient expectations, and overall satisfaction.

Methods:

This was a cross-sectional study of patients who experienced continued impairments following surgical treatment for work-related injuries. The primary outcome was a disease-specific measure, the Western Ontario Rotator Cuff (WORC) index. Patients were categorized into two groups based on the existence of an identifiable reason for surgical failure vs. no reason for failure, as demonstrated by clinical and radiologic investigations and decided upon by a shoulder surgeon and a physical therapist. Analyses included a t-test for independent sample means, linear regression, non-parametric Wilcoxon test, and Fisher''s exact test.

Results:

Thirty-eight consecutive patients were included in the study, and 24 causes of surgical failure were identified in 19 patients (50%). Overall, patients with findings of failure were more disabled according to the total WORC index and had higher levels of symptoms, emotional difficulties, and limitations in sports and recreational activities. Expectations and satisfaction levels were not significantly different between groups.

Conclusion:

Our results indicate that 50% of patients who reported failed surgery had at least one reason to explain their ongoing symptoms, emotional difficulties, and functional limitations.  相似文献   
94.
Research has shown a positive correlation between time spent on homework and learning. However, students often engage in off-task behaviors to escape the demands of homework. Youth with emotional or behavioral disorders (EBD) are especially likely to engage in off-task behaviors. Effective interventions to increase on-task behavior during homework are needed to increase students' academic success. Functional behavioral assessment (FBA) procedures may be helpful for intervention planning; however, there has been limited research on use of FBA with youth with EBD experiencing poor academic performance or task completion problems. In the current study, FBA methods were used to identify the contingencies maintaining the off-task behavior of four youth with behavior problems. Effects of interventions based on functional hypotheses were compared to the effects of interventions not linked to such hypotheses. Discussion focuses on utility of FBA procedures for developing and implementing effective interventions for youth with EBD.  相似文献   
95.
Background Although pemphigus is a rare autoimmune blistering disease, it attracts the attention of physicians of many disciplines. Objective This study aims to assess the number of articles on pemphigus that have been published over 15 years in dermatology vs. non‐dermatology medical journals, and to evaluate the quality of available evidence. Methods PubMed was searched for articles on pemphigus published between 1 January 1993 to 31 December 2007 using the search word pemphigus. Articles were characterized by publication type and journal type per year. Regression analysis was used to determine the effect of year of publication on number of publications of each type. Results The search yielded 2032 publications on pemphigus during the evaluation period. Sixty‐one per cent were published in dermatology journals. Overall, the number of publications increased linearly with time. Most of this increase was accounted for by publications in non‐dermatology journals. There was an increase in clinical trials over the course of the study period. The number of certain publications with lower quality of evidence, mainly case reports and letters to the editor, increased significantly in the last few years. There was no increase in publications with high quality of evidence. Conclusions The increase on data from non‐dermatology disciplines is a welcome contribution. Nevertheless, high‐quality evidence on pemphigus is still lacking. We trust that the current trend towards evidence‐based dermatology will impact future research on this severe disease.  相似文献   
96.
Benign adenomyoepithelioma of the breast is a rare tumor in which the cytologic findings have been described in only a few cases. While benign, the imaging and pathologic features may be mistaken for malignancy. We report the aspiration biopsy findings in four cases of adenomyoepithelioma with radiologic and histologic correlation. Cytopathologists should familiarize themselves with this entity to avoid a misdiagnosis of carcinoma.  相似文献   
97.
Since indium-111 white blood cell (In-111 WBC) scintigraphy is often used to evaluate for osteomyelitis in bone fractures, it is important to know if noninfected fractures have In-111 WBC uptake. Twenty-seven noninfected closed fracture sites in 19 patients were prospectively evaluated with technetium-99m methylene diphosphonate bone scintigraphy and In-111 WBC scintigraphy. In-111 WBC uptake was present in 41% of the 27 sites. In the 11 positive sites, the In-111 WBC uptake was 1+ (definite but minimal) in 55%, 2+ (moderate) in 36%, and 3+ (marked) in 9%. The visual intensity of the radioactive uptake on In-111 WBC scintigrams relative to that on bone scintigrams was less in 82%, equal in 9%, and greater in 9%. The visual size of the area of uptake on In-111 WBC scintigrams and bone scintigrams was smaller in 36%, equal in 55%, and greater in 9%. Factors that may help distinction of In-111 WBC uptake due to fracture alone from infection associated with fracture are discussed.  相似文献   
98.
99.
Sexual reproduction as an adaptation to resist parasites (a review).   总被引:35,自引:1,他引:34       下载免费PDF全文
Darwinian theory has yet to explain adequately the fact of sex. If males provide little or no aid to offspring, a high (up to 2-fold) extra average fitness has to emerge as a property of a sexual parentage if sex is to be stable. The advantage must presumably come from recombination but has been hard to identify. It may well lie in the necessity to recombine defenses to defeat numerous parasites. A model demonstrating this works best for contesting hosts whose defense polymorphisms are constrained to low mutation rates. A review of the literature shows that the predictions of parasite coevolution fit well with the known ecology of sex. Moreover, parasite coevolution is superior to previous models of the evolution of sex by supporting the stability of sex under the following challenging conditions: very low fecundity, realistic patterns of genotype fitness and changing environment, and frequent mutation to parthenogenesis, even while sex pays the full 2-fold cost.  相似文献   
100.
We previously reported assembly and cloning of the synthetic Mycoplasma genitalium JCVI-1.0 genome in the yeast Saccharomyces cerevisiae by recombination of six overlapping DNA fragments to produce a 592-kb circle. Here we extend this approach by demonstrating assembly of the synthetic genome from 25 overlapping fragments in a single step. The use of yeast recombination greatly simplifies the assembly of large DNA molecules from both synthetic and natural fragments.  相似文献   
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