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31.
OBJECTIVES: Histological comparison of human-based (AlloDerm) and porcine-based (ENDURAGen) dermal matrices regarding tissue incorporation and neovascularization as potential soft tissue augmentation materials. STUDY DESIGN: In vivo, rat model. METHODS: Subcutaneous implantation of 1-mm thick, 1 cm x 1 cm pieces of AlloDerm, ENDURAGen, and meshed ENDURAGen was performed in 24 Sprague Dawley rats. Implant materials were harvested at 4 (n = 12) and 8 weeks (n = 12). Histological quantification of soft tissue ingrowth and microvascular density was performed following hematoxylin-eosin staining and CD34 immunohistochemistry, respectively. RESULTS: AlloDerm showed significantly greater soft tissue ingrowth and microvascular density compared with both ENDURAGen and meshed ENDURAGen at 4 and 8 weeks (P < 0.001). CONCLUSIONS: Although these results may differ in human host tissues, AlloDerm seems to be a more suitable dermal matrix implant than ENDURAGen for cases in which tissue incorporation and neovascularization are sought for the optimal outcome based on this animal model.  相似文献   
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This article reviews the interrelationship between panic disorder and vestibular function. There is a possibility of both somatopsychic and psychosomatic interactions between panic and the vestibular system. Another possibility is that vestibular dysfunction could be associated with certain mental disorders, including panic disorder, as a nonspecific marker. Somatopsychic interactions are suggested by findings of high prevalence of vestibular dysfunction in selected patients with panic disorder, by the occurrence of "space and motion phobia" in patients with panic disorder, and by the report of anxiety and pseudoagoraphobia in some patients with a primary complaint of vertigo. Psychosomatic influences include symptoms of dizziness and increased sensitivity of the vestibular system due to anxiety or hyperventilation. Vestibular dysfunction as a nonspecific marker is discussed in the context of a review of studies of the vestibular system in schizophrenia. Before more definite conclusions can be drawn whether panic disorder is related to vestibular dysfunction in some cases, further research is needed to establish the specificity of vestibular dysfunction for panic disorder.  相似文献   
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Patients with diminutive polyps in the rectum or sigmoid colon were randomized to "hot biopsy" treatment for either 1) electrocautery for 2 s (fixed duration cautery) or 2) cautery until visible necrosis of the polyp base was evident (variable duration cautery). Sigmoidoscopy was performed 4 wk after treatment to determine the adequacy of polyp eradication. In the fixed duration cautery group, 11 of 21 polyps (52%) were eradicated, compared with 12 of 14 polyps (86%) in the variable duration cautery group (p = 0.04). When analyzed according to whether or not visible necrosis was achieved (some of the polyps in the fixed duration cautery group showed necrosis with 2 s cautery), 19 of 23 polyps (83%) were eradicated when necrosis was evident, compared to 5 of 12 (42%) without necrosis (p = 0.004). We conclude that hot biopsy treatment for diminutive polyps is significantly more effective when visible necrosis is achieved during cautery. Furthermore, even with visible necrosis, there is a 17% failure rate of polyp eradication.  相似文献   
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The method of the play interview offers the fearful child an opportunity to express himself by speaking for a series of dolls representing siblings, parents, teachers or himself. It is not the child who is aggressive, fearful, jealous or desires the parent's affection, but the doll. In this manner, the child learns to make connections between his fears and his unacceptable bad thoughts, feelings or wishes. Improvement occurs after several play interviews.This article is dedicated to Dr. Leo Kanner (1894–1981), former Director of the Children's Psychiatric Service of the Johns Hopkins HospitalLecture given to the Division of Child Psychiatry, Department of Psychiatry and Behavioral Sciences The Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, Md, 21205, on September 6, 1988.  相似文献   
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Zusammenfassung Es wird über zwei beobachtete Fälle von akuter Myokarditis berichtet, welche im Verlaufe bzw. im Anschlusse an eine akute Infektionskrankheit auftraten, bei denen die elektrokardiographisch festgestellten Störungen des Rhythmus und des Erregungsablaufes für die Stellung der Diagnose von großem Werte waren. In beiden Fällen trat nach einer kurzen Krankheitsdauer völlige Erholung ein.  相似文献   
39.
The aggressive behavior of breast cancer cells can at times be modulated by hormonal mechanisms. Exposure to glucocorticoids (GC) has been shown to stimulate the invasiveness, motility and adhesiveness of breast cancer cells containing the glucocorticoid receptor. This is largely explained by GC-associated overexpression of the c-fms proto-oncogene, which encodes the receptor for the colony stimulating factor-1 (CSF-1). Our objective is to investigate additional GC-associated genetic alterations that could modulate c-fms related malignant behavior in breast cancer cells. A microarray technique using an oligonucleotide array representing 16,700 known expressed human genes was used to analyze the gene expression profile of breast cancer cells exposed to dexamethasone (Dex) or vehicle. Results were confirmed by western blot analysis. Six genes were found to be consistently differentially overexpressed in the Dex-exposed cells compared to control. We focused on serum-glucose kinase 1 (SGK1), a serine-threonine kinase known to be involved in intracellular signal transduction pathways and induced by GC and serum. An adhesion assay was performed on extracellular matrix after exposing the breast cancer cells to Dex, CSF-1 or to Dex or CSF-1 plus LY294002, a functional inhibitor of SGK1 action. Exposure to LY294002 significantly decreased both CSF-1 and Dex-induced adhesiveness to the level of control cells. SGK1 may act as a downstream intracellular regulator of c-fms, particularly of c-fms-induced adhesiveness of breast cancer cells after exposure to GC or CSF-1. This finding may have implications for potential therapeutic interventions aimed at decreasing the aggressiveness of breast cancer cells. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
40.
The aim of this research was to study whether and to what extent Chinese cagA-positive Helicobacter pylori isolates differ from those in The Netherlands. Analysis of random amplified polymorphic DNA (RAPD)-PCR-assessed DNA fingerprints of chromosomal DNA of 24 cagA-positive H. pylori isolates from Dutch (n = 12) and Chinese (n = 10) patients yielded the absence of clustering. Based on comparison of the sequence of a 243-nucleotide part of cagA, the Dutch (group I) and Chinese (group II) H. pylori isolates formed two separate branches with high confidence limits in the phylogenetic tree. These two clusters were not observed when the sequence of a 240-bp part of glmM was used in the comparison. The number of nonsynonymous substitutions was much higher in cagA than in glmM, indicating positive selection. The average levels of divergence of cagA at the nucleotide and protein levels between group I and II isolates were found to be high, 13.3 and 17.9%, respectively. Possibly, the pathogenicity island (PAI) that has been integrated into the chromosome of the ancestor of H. pylori now circulating in China contained a different cagA than the PAI that has been integrated into the chromosome of the ancestor of H. pylori now circulating in The Netherlands. We conclude that in China and The Netherlands, two distinct cagA-positive H. pylori populations are circulating.  相似文献   
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