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Lymph node enlargement may be an incidental finding on examination, or may be associated with a patient complaint. It is likely that over half of all patients examined each day may have enlarged lymph nodes in the head and neck region. There are no written guidelines specifying when further evaluation of lymphadenopathy is necessary. With such a high frequency of occurrence, oral health care providers need to be able to determine when lymphadenopathy should be investigated further. Although most cervical lymphadenopathy is the result of a benign infectious etiology, clinicians should search for a precipitating cause and examine other nodal locations to exclude generalized lymphadenopathy. Lymph nodes larger than 1 cm in diameter are generally considered abnormal. Malignancy should be considered when palpable lymph nodes are identified in the supraclavicular region, or when nodes are rock hard, rubbery, or fixed in consistency. Patients with unexplained localized cervical lymphadenopathy presenting with a benign clinical picture should be observed for a 2- to 4-week period. Generalized lymphadenopathy should prompt further clinical investigation. This article reviews common causes of lymphadenopathy, and presents a methodical clinical approach to a patient with cervical lymphadenopathy.  相似文献   
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Background: Anesthesiologist-directed preoperative medicine clinics are used to prepare patients for the administration of anesthesia and surgery. Studies have shown that such a clinic reduces preoperative testing and consults, but few studies have examined the impact of the clinic on the day of surgery. The authors tested whether a visit to an anesthesia preoperative medicine clinic (APMC) would reduce day-of-surgery case cancellations and/or case delays.

Methods: The authors conducted a retrospective chart review of all surgical cases during a 6-month period at the University of Chicago Hospitals. Case cancellations and rates of first-start case delay over the 6-month period were cross-referenced with a database of APMC attendees in both the general operating rooms and the same-day surgery suite. The impact of a clinic visit on case cancellation and delay in both sites were analyzed separately.

Results: A total of 6,524 eligible cases were included. In the same-day surgery suite, 98 of 1,164 (8.4%) APMC-evaluated patients were cancelled, as compared with 366 of 2,252 (16.2%) in the non-APMC group (P < 0.001). In the general operating rooms, 87 of 1,631 (5.3%) APMC-evaluated patients were cancelled, as compared with 192 of 1,477 (13.0%) patients without a clinic visit (P < 0.001). For both operating areas, APMC patients had a significantly earlier room entry time than patients not evaluated in the APMC.  相似文献   

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The stability of famotidine in total parenteral nutrient (TPN) solutions and the concentrations of amino acids in the presence of famotidine were determined. Two famotidine concentrations (20 mg/L and 40 mg/L) and two amino acid concentrations (20 g/L and 42.5 g/L) were studied under the following storage conditions: refrigerated for 24 hours and then kept at room temperature (20-22 degrees C) for 24 hours, at room temperature for 48 hours, or refrigerated for seven days. Control TPN solutions were studied under the same storage conditions. TPN solutions also contained dextrose 25%, electrolytes, trace elements, and vitamins. Famotidine concentration was determined at 0, 24, and 48 hours and at seven days by high-performance liquid chromatography. Amino acid concentration was determined in the TPN solutions containing 42.5 g/L of amino acids without famotidine and with famotidine 40 mg/L under both 48-hour storage conditions. At 24 hours, all solutions retained at least 95% of the initial famotidine concentration. Seven of the eight famotidine solutions retained more than 95% of the initial famotidine concentration at 48 hours. All samples refrigerated for seven days retained more than 95% of the initial famotidine concentration. The concentration of amino acids in TPN solutions containing 42.5 g/L of amino acids was not affected by the addition of famotidine 40 mg/L under either 48-hour storage condition. Famotidine in concentrations of 20 mg/L and 40 mg/L is stable under the studied 48-hour storage conditions in TPN solutions containing amino acid concentrations of either 20 g/L or 42.5 g/L.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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报道了氯仿重结晶的棉酚的化学性质,样品在不同温度下干燥恒重后,经熔点、薄层层析、紫外光谱、红外光谱、X-射线衍射、热重量分析、元素(C,H,Cl)分析及棉酚合量测定等一系列的分析,确证了在60℃以下棉酚与氯仿成溶剂化物(solvate)。随着干燥温度的升高或在室温长时间的贮存,此现象逐渐消失,100℃真空干燥恒重后成为纯棉酚。  相似文献   
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Acute severe combined demyelination   总被引:2,自引:0,他引:2  
We present a second case in which Guillain-Barré syndrome (GBS) and acute disseminated encephalomyelitis (ADEM) appeared simultaneously, both in acute and fulminant form. The patient, a 10-year-old girl, presented with acute onset of coma and flaccid, areflexic quadriparesis. The elevated CSF protein levels and delayed F waves fulfilled the criteria of GBS and an MRI study revealed extensive multifocal demyelination compatible with a diagnosis of ADEM. Prompt clinical response followed by complete recovery was achieved by treatment with corticosteroids. It is suggested that acute severe combined demyelination might constitute a separate entity in which the demyelinating process, involving simultaneously the central and the peripheral nervous systems, indicates immune response against a component of the myelin of one system carrying cross-antigenicity with the other.  相似文献   
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Infection with human immunodeficiency virus (HIV) and progression to acquired immune deficiency syndrome (AIDS) are associated with a vide variety of morbidities. Local and systemic diseases can develop in association with HIV infection and may manifest themselves as malignancies of the oropharynx. Advances in HIV management, fueled by increasing understanding of molecular pathogenesis, have resulted in marked changes in the prevalence of oral malignant disease. This paper discusses recent trends in the presentation and treatment of malignancies related to HIV and AIDS with an emphasis on malignancies seen in the oral cavity.  相似文献   
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