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81.
OBJECTIVE: Pediatric gastric access for long-term enteral feeding may be performed via a laparotomy, laparoscopy, or a percutaneous approach. In children and adolescents, laparoscopic-assisted gastrostomy may be difficult due to a thick abdominal wall. Therefore, if the abdominal wall is estimated to be >2 cm on physical examination, or in children in whom a percutaneous endoscopic gastrostomy was unsuccessfully attempted by a gastroenterologist, we routinely perform a laparoscopic-assisted percutaneous endoscopic gastrostomy. METHODS: From January 1998 through February 2003, we retrospectively reviewed 15 cases of a laparoscopic-assisted percutaneous endoscopic gastrostomy. Instruments used to perform this technique are a percutaneous endoscopic gastrostomy kit, an Olympus flexible endoscope, and one 5-mm STEP port placed through an infraumbilical incision for a 5-mm, 30-degree scope. RESULTS: Age range was 2 years to 20 years (mean, 10). Operative time ranged from 20 minutes to 45 minutes. When a concurrent laparoscopic Nissen fundoplication was performed (n = 6), the percutaneous endoscopic gastrostomy was placed after completion of the Nissen fundoplication. No intraoperative complications occurred, and all tubes were successfully placed. Feeds were instituted the following day and advanced to goal. To date, no postoperative complications have occurred, and revision has not been necessary. CONCLUSIONS: Laparoscopic-assisted percutaneous endoscopic gastrostomy in children and adolescents is safe and effective. Utilizing laparoscopy permits evaluation of the peritoneum and lysis of adhesions, if necessary. Moreover, laparoscopy provides excellent exposure for accurate placement of the PEG, while avoiding injury to other organs.  相似文献   
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Purpose: Caucasian children with myopia have elevated response accommodative vergence to accommodation (AC/A) ratios. The purpose of this study was twofold: to determine if response AC/A ratios vary with refractive error and with myopic progression rate in Hong Kong Chinese children, and to determine the effect of beta‐adrenergic antagonism with topical timolol application on AC/A ratios. Methods: Thirty children aged eight to 12 years participated in the study. All refractive errors were corrected with spectacle lenses. Accommodative responses were measured using a Shin‐Nippon autorefractor and concurrent changes in vergence were assessed using a vertical prism and a Howell‐Dwyer card at three metres and 0.33 metre. Accommodative demand was altered using plus or minus two dioptre lenses and lens‐ and distance‐induced response AC/A ratios were calculated. Measurements were repeated 30 minutes after the instillation of topical timolol maleate (0.5 per cent). Results: AC/A ratios appeared higher in progressing myopic children but the difference was not statistically significant. Timolol application reduced accommodative convergence (AC) in the stable myopes (reduction = ‐3 ± 1.14A) but not in the emmetropes (0.69 ± 0.9P) or progressing myopes (0.16 ± 0.43A) and this difference between refractive groups was statistically s ignificant (F2,27= 3.766; P= 0.036). However, timolol did not produce a significant change in the accommodative response to positive or negative lenses or response AC/A ratios. Conclusions: We did not find that AC/A ratios in myopic Chinese children were elevated and therefore, it is unlikely that elevated AC/A ratios are responsible for the high levels of myopia that occur in Hong Kong. The finding that timolol reduced AC in the stable myopes suggests that the autonomic control of accommodative convergence in these children may be different from that in emmetropic children and those with progressing myopia.  相似文献   
84.
Obsessive-compulsive disorder (OCD) is a distressing and functionally impairing disorder that can emerge as early as age 4. Cognitive behavior therapy (CBT) for OCD in youth shows great promise for amelioration of symptoms and associated functional impairment. However, the empirical evidence base for the efficacy of CBT in youth has some significant limitations, particularly as related to treating the very young child with OCD. This report includes a quantitative review of existing child CBT studies to evaluate evidence for the efficacy of CBT for OCD. It identifies gaps in the literature that, when addressed, would enhance the understanding of effective treatment in pediatric OCD. Finally, it presents a proposed research agenda for addressing the unique concerns of the young child with OCD.  相似文献   
85.
This in vitro biomechanical study used cadaveric specimens to compare the rotator cuff repair fixation provided by BioCorkscrew and Bioknotless RC suture anchors. Three cm wide by 1-cm long full-thickness supraspinatus defects were repaired using either two BioCorkscrew suture anchors with combined vertical and horizontal mattress sutures (n = 7) or three Bioknotless RC suture anchors with simple sutures (n = 7). Therefore, the BioCorkscrew suture anchor group had two sutures per anchor (four total sutures), while the Bioknotless RC suture anchor group had one suture per anchor (three total sutures). Two-phase cyclic (5–100 N, 1,000 cycles and 5–180 N, 2,000 cycles) and load to failure tests (31 mm/s) were performed. Non-parametric statistics were used to compare group differences (P < 0.05). All of the BioCorkscrew group specimens (seven of seven) completed the two phase cyclic test regimen without failure or gapping ≥ 5 mm, compared to only three of seven of the Bioknotless RC group (Fisher’s Exact test = 0.03). Groups did not differ for repair site gapping during the 5–100 N cyclic test phase (Fisher’s Exact test = 0.77), however more of the Bioknotless RC group displayed gapping ≥ 5 mm during the 5–180 N cyclic test phase than the BioCorkscrew group (P = 0.02). The BioCorkscrew group also displayed greater yield load during load to failure testing (492.2 ± 204 N vs. 296.4 ± 155 N, P = 0.03). In this in vitro biomechanical study, the BioCorkscrew group with combined vertical and horizontal mattress sutures displayed greater cyclic test survival, less repair site gapping, and superior yield load compared to the Bioknotless RC group with simple sutures. These results in human cadaveric rotator cuff-humerus specimens suggest better immediate post-operative repair site strength and a reduced need for post-operative restrictions. Clinical studies are needed to determine how these rotator cuff repair modes withstand the forces of early rehabilitation and activities of daily living that potentially influence patient outcomes.  相似文献   
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Siberian ginseng ([SG]; Eleutherococcus senticosus) is a commonly used herbal preparation. The objective of this study was to assess in normal volunteers (n = 12) the influence of a standardized SG extract on the activity of cytochrome P450 CYP2D6 and 3A4. Probe substrates dextromethorphan (CYP2D6 activity) and alprazolam (CYP3A4 activity) were administered orally at baseline and again following treatment with SG (1 x 485 mg twice daily) for 14 days. Urinary concentrations of dextromethorphan and dextorphan were quantified, and dextromethorphan metabolic ratios (DMRs) were determined at baseline and after SG treatment. Likewise, plasma samples were collected (0-60 h) for alprazolam pharmacokinetics at baseline and after SG treatment to assess effects on CYP3A4 activity. Validated high performance liquid chromatography methods were used to quantify all compounds and relevant metabolites. There were no statistically significant differences between pre- and post-SG treatment DMRs indicating a lack of effect on CYP2D6 (P > 0.05). For alprazolam there also were no significant differences in the pharmacokinetic parameters determined by noncompartmental modeling (C(max), T(max), area under the curve, half-life of elimination) indicating that SG does not significantly induce or inhibit CYP3A4 (P > 0.05). Our results indicate that standardized extracts of SG at generally recommended doses for over-the-counter use are unlikely to alter the disposition of coadministered medications primarily dependent on the CYP2D6 or CYP3A4 pathways for elimination.  相似文献   
89.
We have studied the lateral rectus muscles and neuromuscular junctions (NMJs) of abducens motoneurons in wobbler (wr/wr) mutant mice from 26 to 58 days of age. The muscles of wr/wr weighed about 70% of the weight of littermate controls and were composed of fiber types comparable to those of controls, as assayed by succinate dehydrogenase activity. The most obvious difference between wr/wr and control NMJs was a reduction in the length of the postjunctional membrane of wr/wr mice. The mutant muscle endplate membrane was only about 70% (6.58 micron) the length of control muscle regions (9.44 micron). There were no obvious differences at the light microscopic level in the distribution of acetylcholine (ACh) receptors at junctional regions or staining of acetylcholinesterase, as assayed with alpha-bungarotoxin binding or enzyme histochemistry. Indirect immunocytochemical studies using antibodies directed against the subunits of the ACh receptor failed to indicate an abnormal presence of immature receptors clustered at the NMJs of wr/wr mice. Our findings suggest that the formation or maintenance of normal postjunctional folds and the differentiation of receptors at the junctions are under independent control during development. Furthermore, the wobbler mutation may affect muscle cell differentiation as well as neuronal differentiation. This mutant mouse should prove a useful model for study of postjunctional fold formation and function.  相似文献   
90.
In this report, we show that in the human astroglioma cell line D54-MG, both interleukin-1 (IL-1β) and tumor necrosis factor-alpha (TNF-α) enhance C3 gene expression in a time- and dose-dependent manner. Kinetic analysis demonstrates that after 96 h, C3 mRNA levels increase approximately 30-fold and 20-fold in response to IL-1β or TNF-α, respectively. C3 protein production increases proportionally, reaching levels 36-fold and 18-fold higher than untreated controls upon exposure to IL-1β or TNF-α, respectively. D54-MG cells require a minimal 1 h exposure to IL-1β in order to enhance C3 gene expression significantly, while 4 to 8 h are required for TNF-α. Simultaneous treatment of D54-MG cells with IL-1β and interferon-gamma (IFN-γ) resulted in an additive increase in both C3 mRNA and protein expression, a finding not seen with the combination of TNF-α and IFN-γ. Primary rat astrocytes also express increased C3 mRNA levels after 48 h in response to IL-1β (5.3-fold increase) and TNF-α (7-fold increase), while an additive effect was observed upon simultaneous treatment with both IL-1β and IFN-γ. In the central nervous system (CNS), endogenous complement and cytokine production by astrocytes, and enhancement by IFN-γ, a product of activated T cells often seen in the CNS in neural autoimmune disease, may contribute to the pathogenesis of inflammatory demyelinating diseases such as multiple sclerosis.  相似文献   
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