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91.
The optimal form of rehabilitation after rotator cuff repair has yet to be determined. A randomised clinical trial was undertaken to compare outcomes for two forms of rehabilitation for this condition: individualised supervised physiotherapy treatment, and a standardised unsupervised home exercise regime. Fifty-eight volunteers with all sizes of operatively repaired rotator cuff tears were allocated randomly to one of the two treatment groups. All subjects received a standardised home exercise regime. Subjects who were randomised to the physiotherapy group received additional individualised treatment. Independent, blinded assessments of range of motion, muscle force and functional outcome measures were performed pre-operatively, and at six, 12 and 24 weeks postoperation. At six, 12 and 24 weeks post-operation, comparable outcomes were demonstrated for both rehabilitation groups. By 24 weeks post-operation, most subjects demonstrated outcomes that were consistent with a favourable recovery, regardless of rehabilitation mode. On the basis of these results, outcomes for subjects allocated to individualised physiotherapy treatment after rotator cuff repair are no better than for subjects allocated to a standardised home exercise regime.  相似文献   
92.
BACKGROUND: Isotretinoin is a known teratogen, and when it is prescribed to women of childbearing potential, 2 forms of contraception must be used, commonly including hormonal contraception. Although isotretinoin and estradiol are metabolized largely by cytochrome P450 (CYP) 3A4 and glucuronidation, the potential for clinical drug interaction, with subsequent pharmacodynamic impact, has not been evaluated. METHODS: We enrolled 26 healthy women who were to receive isotretinoin for the treatment of severe, recalcitrant nodular acne and who were taking or planning to take oral contraceptives. The pharmacokinetics of ethinyl estradiol and norethindrone (INN, norethisterone) (the components of Ortho Novum 7/7/7; Ortho-McNeil Pharmaceutical, Inc, Raritan, NJ) and pharmacodynamic assessments of oral contraceptive effectiveness (concentrations of serum progesterone, luteinizing hormone, and follicle-stimulating hormone) were determined on days 6 and 20 of 2 separate oral contraceptive cycles, before and during isotretinoin treatment. RESULTS: The addition of isotretinoin to the oral contraceptive regimen resulted in small and inconsistent, although statistically significant (P <.04), decreases in the concentrations of both ethinyl estradiol (9% decrease in area under the plasma concentration-time curve from time 0 to 24 hours after the dose on day 6) and norethindrone (11% decrease in maximum plasma concentration on day 20). Isotretinoin did not cause any statistically significant increases in pharmacodynamic markers, although a majority of women had increases in these measures. Although there was no correlation between isotretinoin (or metabolite) levels and oral contraceptive levels (P >.05), there was a correlation between progesterone level and oral contraceptive levels (P <.05). Variability was large for both pharmacokinetic measures (median coefficients of variation of 44%-69% [for each time point within a study period]) and pharmacodynamic measures (median coefficients of variation of 64%-114%). One woman in each study phase, one before and one during isotretinoin treatment, had a progesterone elevation consistent with possible ovulation. No serious or unexpected adverse events were observed. CONCLUSIONS: The small reduction in ethinyl estradiol and norethindrone levels associated with isotretinoin was not associated with any pharmacodynamic changes in our study. The combination of the teratogenic risk of isotretinoin and the large variability of and correlation between oral contraceptive levels and pharmacodynamic measures, however, strongly reinforces the necessity of additional contraceptive methods during concomitant administration of these drugs.  相似文献   
93.
Orbital apex syndrome secondary to mucormycosis in immuno-compromised patients is well described; however, few reports exist of a paranasal sinus mycetoma resulting in this presentation in the immuno-competent patient. The case is reported of a 92-year-old man who developed orbital apex syndrome secondary to a sphenoidal sinus mycetoma of Pseudallescheria boydii.  相似文献   
94.
A symposium at the 2003 Annual Meeting of the Society of Toxicology brought together an expert group of endocrinologists to review how non-reproductive hormones can affect the endocrine system. This publication captures the essence of those presentations. Paul Cooke and Denise Holsberger recapitulate the evidence of how thyroid hormones affect male and female reproduction, and reproductive development. Ray Witorsch summarizes the many effects of glucocorticoids on the reproductive system. Finally, Paul Sylvester reviews the mechanism of action of prolactin, and reminds us that this ancient hormone has many functions beyond lactation.  相似文献   
95.
Aortic intimal sarcomas are rare among the already uncommon primary aortic neoplasms. Due to a low index of suspicion, characteristic radiographic and clinical findings are sometimes misattributed and the diagnosis is not made until autopsy. We describe the helical CT findings of a patient with an advanced aortic intimal sarcoma, intraluminal and extraluminal disease, and extensive metastases.  相似文献   
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98.
The spatial distribution and coordination of vesicular dynamics within growth cones are poorly understood. It has long been thought that membranous organelles are concentrated in the central regions of growth cones and excluded from filopodia; this view has dramatically shaped conceptual models of the cellular mechanisms of axonal growth and presynaptic terminal formation. To begin to test these models, we studied membrane dynamics within axonal growth cones of living rat cortical neurons. We demonstrate that growth cone filopodia contain vesicles that transport synaptic vesicle proteins bidirectionally along filopodia and fuse with the filopodial surface in response to focal stimulation, allowing for both local secretion of vesicular contents and rapid changes in the plasma membrane composition of individual filopodia. Our results suggest a new model in which growth cone filopodia are actively involved in both emitting and responding to local signals related to axon growth and early synapse formation.  相似文献   
99.
Most individuals with Williams syndrome (WS) have a 1.6 Mb deletion in chromosome 7q11.23 that encompasses the elastin (ELN) gene, while most families with autosomal dominant supravalvar aortic stenosis (SVAS) have point mutations in ELN. The overlap of the clinical phenotypes of the two conditions (cardiovascular disease and connective tissue abnormalities such as hernias) is due to the effect of haploinsufficiency of ELN. SVAS families often have affected individuals with some WS facial features, most commonly in infancy, suggesting that ELN plays a role in WS facial gestalt as well. To find other genes contributing to the WS phenotype, we studied five families with SVAS who have small deletions in the WS region. None of the families had mental retardation, but affected family members had the Williams Syndrome Cognitive Profile (WSCP). All families shared a deletion of LIMK1, which encodes a protein strongly expressed in the brain, supporting the hypothesis that LIMK1 hemizygosity contributes to impairment in visuospatial constructive cognition. While the deletions from the families nearly spanned the WS region, none had a deletion of FKBP6 or GTF2I, suggesting that the mental retardation seen in WS is associated with deletion of either the centromeric and/or telomeric portions of the region. Comparison of these five families with reports of other individuals with partial deletions of the WS region most strongly implicates GTF2I in the mental retardation of WS.  相似文献   
100.
The effects of propentofylline, a xanthine derivative and adenosine transport inhibitor, were evaluated following anteromedial cortex lesion in the rat. Propentofylline (2x/10 mg/kg, intraperitoneally) was administered for 7 days post-insult and basic fibroblast growth factor (bFGF) immunoreactivity measured at designated time points in the peri-lesional cortex and ipsilateral dorsal striatum. The spatiotemporal pattern of bFGF expression was then compared to functional recovery patterns. Propentofylline-treated animals displayed increased bFGF expression in the peri-lesional cortex which may have contributed to the observed early facilitation of functional recovery. Drug administration did not, however, produce a change in bFGF expression in the ipsilateral dorsal striatum compared to saline-treated animals. These findings taken together with other positive findings regarding propentofylline, support the drug's therapeutic potential.  相似文献   
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