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PURPOSE: Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal-dominant peripheral neuropathy that results from deletion of a 1.5-Megabase pair (Mb) segment of the short arm (p) of chromosome 17. Hereditary neuropathy with liability to pressure palsies increases susceptibility of peripheral nerves to pressure and trauma and can be associated with symptoms at multiple anatomic entrapment sites. Many patients present with multiple upper-extremity entrapment neuropathies and the etiology is uncertain. We hypothesized that some of these patients have an underlying hereditary neuropathy. The purpose of this study was to determine the prevalence of HNPP in patients with multiple surgically treated upper-extremity entrapment neuropathies. METHODS: The inclusion criterion for the study was history of more than 1 carpal tunnel release and/or ulnar nerve transposition. The exclusion criteria were history of diabetes or history of Charcot-Marie-Tooth neuropathy. Fifty-nine patients were in the study group. Two patients known to have the 17p11.2 deletion were used as controls. Genomic DNA was extracted from peripheral blood. Each sample was genotyped using polymerase chain reaction (PCR) amplification with short tandem repeat polymorphism markers within the 1.5-Mb region of 17p deleted in HNPP. Markers were scored as homozygous or heterozygous after resolution by polyacrylamide gel electrophoresis and silver staining. RESULTS: The 2 control patients were homozygous for 11 markers. None of the 59 study patients were homozygous for all markers tested in the deleted region. No study patient had the 17p deletion diagnostic for HNPP. Based on the sample size of 59 patients the 95% confidence interval for the prevalence of the 17p11.2 deletion in this population is 0% to 5%. CONCLUSIONS: We found no evidence for an association between HNPP and patients who have multiple surgical releases for upper-extremity entrapment neuropathies.  相似文献   
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Surface and bulk modification techniques of polydimethylsiloxane (PDMS) polymers were used to develop a new intracochlear electrode that can closely hug the inner wall of scala tympani. Laser-induced surface grafting of poly (2-hydroxyethyl methacrylate) (PHEMA) and sequential method for preparation of interpenetrating polymer networks (IPNs) of PDMS/PHEMA were, respectively, used for surface and bulk modifications. The hydrogel content and water-uptake capability of the modified samples were optimized by Taguchi method for experimental design. The modified PDMS samples were examined by performing attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, water contact-angle measurement, and peel strength tests. The performances of actual-sized fabricated electrodes were assessed inside a transparent model of scala tympani, which was filled with saline. After a swelling process, the hydrophilic branch begins to elongate and detach from hydrophobic branch and pushes it toward the inner wall.  相似文献   
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A re-investigation of the chemical constituents of the stem bark of Symplocos racemosa Roxb. led to the isolation of four new glycosides, symplocomoside (1), symponoside (2), symplososide (3) and symploveroside (4). Benzoylsalireposide (5) and salireposide (6) were re-isolated from this plant. The structures of the new compounds were determined by 1D and 2D-homonuclear and heteronuclear NMR spectroscopy, chemical evidence, and by comparison with the published data of the closely related compounds. The glycosides 1-4 displayed in vitro inhibitory activity against phosphodiesterase I with IC50 values of 122 +/- 0.017, 698 +/- 0.06, 722 +/- 0.03, 909 +/- 0.09 microM, respectively. The compounds 1-6 also showed in vitro inhibitory activity against thymidine phosphorylase with IC50 values of 189.96 +/- 1.02, 195.56 +/- 2.36, 207.61 +/- 1.06, 488.89 +/- 4.10, 427.20 +/- 5.36, 354.2 +/- 5.69 microM, respectively while 1 was also found to be a urease inhibitor with an IC50 value of 54.13 +/- 0.71 microM.  相似文献   
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Lower gastrointestinal bleeding in elderly patients   总被引:4,自引:0,他引:4  
Lower gastrointestinal bleeding (LGIB) is one of the common medical emergencies that can become life-threatening in elderly patients. Increased prevalence of cerebrovascular and cardiovascular diseases, malignancy, polypharmacy, and the use of nonsteroidal anti-inflammatory drugs in elderly patients adversely affects the outcome of LGIB. Diverticular bleeding, vascular ectasia, polyps and hemorrhoids are among the common causes of LGIB in the elderly. In a majority of cases, LGIB stops spontaneously with resuscitation and supportive therapy. In those elderly patients in whom LGIB continues, benefits of endoscopic, angiographic, or surgical intervention should not be withheld because of age alone. However, the timing of tests and the type of intervention should be custom tailored for frail elderly patients. Such a decision should depend upon functional status, its impact on outcome, and the consent process.  相似文献   
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OBJECTIVES: To compare the use of preventive practices of Hispanic- and African-American women aged 50 and older. DESIGN: A cross-sectional survey. SETTING: Inpatient and outpatient units of a teaching hospital located in South Central Los Angeles. PARTICIPANTS: Convenience sample of 337 women aged 50 and older. MEASUREMENTS: Demographic and lifestyle characteristics and selected preventive practices. Preventive practices reported were self-breast examination, mammography, Papanicolaou (Pap) smear, digital rectal examination and stool occult blood examination, sigmoidoscopy, chemoprophylaxis, and immunization. Information was obtained in a face-to-face interview. RESULTS: African-American women were more likely to have had a Pap smear ever and to have used aspirin prophylaxis than Hispanic women. CONCLUSION: There were no major differences in the use of preventive services by the two ethnic groups except for Pap smear and aspirin use. Immunization and colorectal cancer screening rates were low in African-American and Hispanic women.  相似文献   
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