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991.
OBJECTIVE: To improve smiling after long-term facial nerve palsy (FNP). Physiotherapy rehabilitation of an adapted (more symmetrical) smile was investigated in FNP subjects 1 year post-onset, using video self-modeling (video replay of only best adapted smiles) and implementation intentions (preplanning adapted smiles for specific situations). STUDY DESIGN AND SETTING: Prospective, blinded clinical trial. Facial-Nerve-Palsy Clinic. RESULTS: After video self-modeling: 1) reaction time (RT) to initiation of adapted smiles became 224 ms faster whereas RT for everyday (asymmetrical) smiles became 153 ms slower; 2) adapted smiles were completed 544 ms faster; 3) adapted smiles had higher overall quality, movement control, and symmetry ratings; and 4) Facial Disability Index scores also improved. Implementation intentions after video self-modeling ensured transfer of adapted smile to everyday situations. CONCLUSION: Following intervention the smile improved, with significant changes in availability, execution speed, and quality. SIGNIFICANCE: This study supports these rehabilitation techniques to maximize quality of smiling following FNP. EBM rating: B-2b.  相似文献   
992.
Variation in the risk of breast cancer observed among women and among populations may be explained by variation in lifetime exposure to estrogens. The suppressive effect of exercise on estradiol levels in women is well documented, but it is unknown whether habitual (i.e. typical daily) physical activity has a similar effect. Epidemiological data suggest that physical activity is one of the few modifiable factors capable of reducing the risk of breast cancer in women. We investigated whether variation in the amount of habitual activity corresponds to variation in estradiol levels in women of reproductive age. One hundred and thirty-nine regularly menstruating women 24-37 years of age collected daily saliva samples for one complete menstrual cycle and kept a daily log of physical activity. Saliva samples were analyzed for concentration of estradiol. We observed a negative relationship between habitual physical activity and salivary levels of estradiol. Mean estradiol was 21.1 pmol/l in the low, 17.9 pmol/l in the moderate and 16.6 pmol/l in the high activity group (all pairwise differences were statistically significant at P<0.009). A strong association exists between physical activity and levels of estradiol among women of reproductive age. A modern lifestyle, characterized by reduced physical activity, may therefore contribute to a rise in the levels of estradiol produced during menstrual cycles and thus to higher cumulative lifetime exposure to estradiol, resulting in a higher risk of breast cancer.  相似文献   
993.
994.
Fipronil is a phenylpyrazole insecticide designed to selectively inhibit insect gamma-aminobutyric acid (GABA) receptors. Although fipronil is often used in or near aquatic environments, few studies have assessed the effects of this neurotoxicant on aquatic vertebrates at sensitive life stages. We explored the toxicological effects of fipronil on embryos and larvae using the zebrafish (Danio rerio) experimental model system. Embryos exposed to fipronil at nominal concentrations at or above 0.7 microM (333 mug/l) displayed notochord degeneration, shortening along the rostral-caudal body axis, and ineffective tail flips and uncoordinated muscle contractions along the body axis in response to touch. This phenotype closely resembles zebrafish locomotor mutants of the accordion class and is consistent with loss of reciprocal inhibitory neurotransmission by glycinergic commissural interneurons in the spinal cord. Consistent with the hypothesis that notochord degeneration may be due to abnormal mechanical stress from muscle tetany, the expression patterns of gene and protein markers specific to notochord development were unaffected by fipronil. Moreover, the degenerative effects of fipronil (1.1 microM) were reversed by coexposure to the sodium channel blocker MS-222 (0.6mM). The notochord effects of fipronil were phenocopied by exposure to 70 microM strychnine, a glycinergic receptor antagonist. In contrast, exposure to gabazine, a potent vertebrate GABA(A) antagonist, resulted in a hyperactive touch response but did not cause notochord degeneration. Although specifically developed to target insect GABA receptors with low vertebrate toxicity, our results suggest that fipronil impairs the development of spinal locomotor pathways in fish by inhibiting a structurally related glycine receptor subtype. This represents an unanticipated and potentially novel mechanism for fipronil toxicity in vertebrates.  相似文献   
995.
996.
997.
BACKGROUND CONTEXT: Posterior lumbar interbody fusion (PLIF) was introduced 50 years ago. The Lumbar I/F cage (DePuy Spine, Raynham, MA) was designed to enhance PLIF results. PLIF with the Lumbar I/F cage and posterior Variable Screw Placement System (VSP) has increased the success of fusion to nearly 100% at the four lowest lumbar levels, L2-L3 through L5-S1. Less commonly, PLIF is indicated for the L1-L2 level. Clinical-results of Lumbar I/F cage fusion and VSP at L1-L2 have-not been reported. PURPOSE: The purpose of this study is to report the functional outcomes, fusion rate, and complications related to PLIF with Lumbar I/F cage and VSP of L1-L2 STUDY DESIGN/SETTING: The setting is a retrospective, single-arm cohort study of consecutive PLIF surgical patients at a single center. PATIENT SAMPLE: A review of 373 of 425 patients who underwent PLIF with Lumbar I/F cage and VSP from 1999 to 2002 identified 12 patients who had PLIF with Lumbar I/F cage and VSP at L1-L2. Mean follow-up was 31 months (range 12-65 months). OUTCOME MEASURES: Clinical success was determined with a modified Prolo score evaluating pain, function, medication usage and economic status. Fusion success, determined by evaluation of plain radiographs, was defined by continuous bone bridging the fusion area with no lucencies. METHODS: The 12 patients were evaluated for clinical success and/fusion success at last follow-up. These results were compared with the results of the 373 patients reviewed, and historical groups of the original Investigational Device Exemption study and the 10-year follow-up study. RESULTS: Previous surgery was reported by 10 of 12 patients, with an average symptom-free period of 3 years after previous fusion and before presentation with severe symptomatology necessitating further surgery at L1-L2. Seven patients had clinical success (59%), and five patients were clinically unsuccessful (41%). This included zero excellent, 2 of 12 (15%) good, 5 of 12 (42%) fair, and 5 of 12 (42%) poor results. Fusion was successful in seven (58%) and failed in five patients (42%). Three failed fusions were associated with L1-L2 subsidence. Two patients required further revision for non-union. CONCLUSIONS: In 12 patients with L1-L2 fusion, we report an unexpected high rate of failed fusion and poor clinical outcome.  相似文献   
998.
999.
OBJECTIVES: This study was performed to evaluate the clinical and serial angiographic outcomes of patients undergoing sirolimus-eluting stent (SES) implantation for unprotected left main coronary artery (LMCA) stenosis. BACKGROUND: The efficacy of SES has led to their expanded use for off-label indications, including LMCA disease. METHODS: Unprotected LMCA intervention with SES was attempted in 50 patients. Surveillance angiography was performed at three and nine months' follow-up. RESULTS: The target lesion involved the distal LMCA in 47 patients (94%). In-lesion restenosis occurred in 21 patients (42%), was focal in 85% of cases, and in 82% involved the branch ostia, sparing the LMCA itself. Target lesion revascularization (TLR) occurred in 19 patients (38%) over a mean follow-up of 276 +/- 57 days; TLR was ischemia-driven in 7 patients (14%). Late loss was significantly greater within the left circumflex (LCX) ostium compared to the parent vessel (PV) of the LMCA bifurcation (0.83 +/- 0.89 mm vs. 0.49 +/- 0.72 mm, p = 0.04). Late loss continued to increase between three- and nine-month follow-up. Final minimal luminal diameter and maximal balloon pressure were independent predictors of restenosis of the PV. CONCLUSIONS: Restenosis is a frequent finding when serial angiographic follow-up is performed after SES implantation for unprotected distal LMCA lesions. Restenosis is usually focal, most often involves the LCX ostium, and often occurs without symptoms.  相似文献   
1000.
Enteric microbial flora, bacterial overgrowth, and short-bowel syndrome.   总被引:1,自引:0,他引:1  
Small intestinal bacterial overgrowth (SIBO) occurs commonly in short-bowel syndrome (SBS) and, in some instances, may result in significant problems. SIBO is characterized by a variety of signs and symptoms resulting from nutrient malabsorption caused by an increased number and/or type of bacteria in the small intestine. The anatomic and physiologic changes that occur in SBS together with medications commonly used in these patients facilitate the development of SIBO. Because many aspects related to SIBO in the SBS population remain poorly understood, it was our aim to review the current understanding of the gut flora and issues related to SIBO occurring in SBS.  相似文献   
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