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排序方式: 共有2063条查询结果,搜索用时 46 毫秒
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Bela Prajapaty Bharat Shah 《Indian journal of otolaryngology and head and neck surgery》1997,49(4):391-393
The pyriform sinus fistula is rare congenital anomaly of either third or fourth branchial pouch, which most frequently presented itself by recurrent episodes of neck abscess for long time. Majority of patients with this anomaly presented with symptoms before 10 years and it is more common than has previously been commonly found on leftside (93%). Clinically high index of suspicion, cannulation of the tract under general anaesthesia, Direct laryngoscopy and fistulogram have freequently been successful in identifying the presence of these embryological remnants. Surgical exploration of sinus tract with its total excision, guided with cannula inside its lumen is the definitive treatment. 相似文献
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Dhawan Subhash; Puri Raj K.; Kumar Ashok; Duplan Helen; Masson Jean-Michel; Aggarwal Bharat B. 《Blood》1997,90(4):1535-1544
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Edward J Hepworth Matthew Bucknor Ankit Patel Winston C Vaughan 《Otolaryngology--head and neck surgery》2006,135(1):68-73
OBJECTIVE: To evaluate impressions and usage of sinus surgery image-guided surgical (IGS) systems by ENT surgeons in the United States. STUDY DESIGN AND SETTING: A survey was mailed to selected practicing ENT physicians, investigating regional information, practice type, IGS usage patterns, perceived benefits and limitations, and usage of the 61795 surgery code. RESULTS: Seventy-three percent of respondents use IGS. Nonusers respond that it provides no benefit or is too expensive. Eighty percent of respondents replied that IGS may allow for increased safety in certain procedures. Most users attempt reimbursement with the 61795 code. CONCLUSION: IGS usage is increasing but appears to be perceived as expensive and nonbeneficial in certain situations. Most respondents, however, felt that IGS may lead to safer surgery in certain situations, including revision and frontal procedures. Several factors appear to limit routine use including ease of use, technical setup, code reimbursement, and initial purchase costs. SIGNIFICANCE: IGS use appears to be increasing. The most frequent users appear to agree with the previously issued AAO-HNS guidelines regarding appropriate indications. Expanded use may depend on ease of use, reimbursement, and affordability. EBM rating: D-5. 相似文献
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BACKGROUND CONTEXT: Intramedullary fat-containing benign childhood tumors of the cord include lipomas, dermoid cysts, and teratomas. These are embryonal tumors. Most intramedullary fat-containing tumors are solitary. Multiple intramedullary lipomas are rare and may represent a spinal lipomatous malformation. The presence of another intramedullary dermoid tumor in the same case is rare. PURPOSE: The intent of this case report is to look at magnetic resonance features and possible mechanisms of association of these fat-containing intramedullary tumors. STUDY DESIGN/SETTING: A 3-year-old male child presented with spastic quadriplegia. METHODS: Magnetic resonance imaging (MRI) of spine was done on a 1.5-T scanner in different planes. RESULTS: MRI showed multiple intramedullary spinal lipomas with an intramedullary dermoid involving the conus, cord atrophy, and subarachnoid fat droplets. CONCLUSION: Multiple intramedullary lipomas with an intramedullary dermoid represent a form of spinal lipomatous malformation. Both may represent embryogenic mesenchymal inclusions and hamartomatous growth, which can be accurately diagnosed with MRI. 相似文献
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HIV seroincidence among patients at clinics for sexually transmitted diseases in nine cities in the United States 总被引:1,自引:0,他引:1
Weinstock H Dale M Gwinn M Satten GA Kothe D Mei J Royalty J Linley L Fridlund C Parekh B Rawal BD Busch MP Janssen RS 《Journal of acquired immune deficiency syndromes (1999)》2002,29(5):478-483
Although the numbers of newly reported diagnoses of AIDS decreased in the 1990s, it is not clear whether they reflect a decreasing number of new HIV infections. Direct measurement of HIV incidence through follow-up cohort studies is difficult and costly. We estimated HIV incidence and trends in incidence among men who have sex with men (MSM) and heterosexual men and women at clinics for sexually transmitted diseases (STDs) by using a recently developed serologic testing algorithm that requires only a single blood specimen. Cross-sectional anonymous serosurveys were conducted at 13 STD clinics in nine cities in the United States from 1991 through 1997. Before anonymous HIV testing, demographic and clinical information was abstracted. Of 129,774 specimens tested, 362 (0.28%) were from persons estimated to be recently infected. Incidence among MSM was 7.1% (95% confidence interval (CI): 4.8-10.3), 14 times higher than that among heterosexuals, which was 0.5% (CI: 0.4- 0.7). Incidence among MSM and heterosexuals remained unchanged during the time studied. Decreasing rates of new AIDS diagnoses in the 1990s do not reflect stable rates of new HIV infections among MSM and heterosexual patients attending these clinics. 相似文献
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The cytokine tumor necrosis factor was originally identified as a protein that kills tumor cells. So far, 18 distinct members of this family have been identified. All of them regulate cell survival, proliferation, differentiation, and cell death, also called apoptosis. The apoptosis induced by TNF, and other members of the family, for example, FasL, VEGI, and TRAIL is mediated through death receptors. The apoptotic signals by these cytokines are transduced by eight different death domain- (DD) containing receptors (TNFR1, also called DR1; Fas, also called DR2; DR3, DR4, DR5, DR6, NGFR, and EDAR). The intracellular portion of all these receptors contains a region approximately 80 amino acids long referred to as the death domain. Upon activation by its ligand, the DD recruits various proteins that mediate both death and proliferation of the cells. These proteins in turn recruit other proteins via their DDs or death effector domains. The actual destruction of the cell, however, is accomplished by serial activation of a family of proteases referred to as caspases. Cell death is negatively regulated by a family of proteins that includes decoy receptors, silencer of DD, sentrin, cellular FLICE inhibitory protein, cellular inhibitors of apoptosis, and survivin. This review is an attempt to describe how these negative and positive players of cell death perform a harmonious dance with each other. 相似文献
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Polyclonal anti-PSA is more sensitive but less specific than monoclonal anti-PSA: Implications for diagnostic prostatic pathology 总被引:3,自引:0,他引:3
Varma M Morgan M Jasani B Tamboli P Amin MB 《American journal of clinical pathology》2002,118(2):202-207
Prostate-specific antigen (PSA) production by nonprostatic tissues has been reported, casting doubts on its specificity. The immunohistochemical relative specificity and sensitivity of PSA expression using monoclonal and polyclonal anti-PSA was analyzed on 60 prostate carcinomas, 40 normal seminal vesicles, and 310 nonprostatic tumors. All nonprostatic tumors proved negative with both antibodies. However, 13 (32%) seminal vesicles showed immunoreactivity with polyclonal anti-PSA, but none showed immunoreactivity with the monoclonal antibody. The sensitivity of the 2 antibodies for prostate cancer varied with tumor grade. In Gleason pattern 3, both antibodies showed diffuse immunostaining in all cases. In Gleason pattern 5, polyclonal anti-PSA showed diffuse (>95%) tumor cell positivity in 18 cases (90%), while with the monoclonal antibody, 7 cases (35%) showed only focal (<10%) tumor cell immunoreactivity. Thus, monoclonal anti-PSA seems to be useful in small gland proliferations in which the differential diagnosis includes seminal vesicle, while for poorly differentiated neoplasms, polyclonal anti-PSA is considered superior. Sections of high-grade prostate cancer should be included as positive controls for PSA immunostaining. 相似文献