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41.
Background. Nasopharyngeal carcinoma has a variety of presentations. However, in more than 50% of cases it may present with serous otitis or cervical metastases. Although the metastases usually occur in the neck, the lymphatic network of the parotid may also serve as a site for the metastatic deposits. We present a case in which the initial manifestation of nasopharyngeal carcinoma of the lymphoepithelioma type was a parotid mass. Methods. Case study. Results. A patient who was initially seen with an isolated parotid mass was found to have an undifferentiated carcinoma of the lymphoepithelial type. Further evaluation identified an occult nasopharyngeal carcinoma, and the patient underwent radiotherapy. Conclusions. A diagnosis of a malignant lymphoepithelial lesion of the parotid gland or undifferentiated carcinoma of the lymphoepithelial type mandates a search for an occult primary nasopharyngeal tumor.  相似文献   
42.
Purpose

To review the efficacy, effectiveness and safety of hemostatic drugs to reduce surgical blood loss.

Methods

Analysis of randomized controlled trials and metaanalyses exploring the efficacy of desmopressin, aprotinin, lysine analogues and recombinant activated factor VII (rFVIIa) on clinically important endpoints.

Main findings

Although potentially useful in surgical patients with mild hemophilia or type I von Willebranďs disease, desmopressin has no proven benefit in patients without previous hemostatic defects. Aprotinin has been studied extensively in cardiopulmonary bypass surgery, with evidence of a blood sparing effect. Additional benefits are suggested. The drug is less consistently effective in liver transplantation and major orthopedic surgery. Although rare, hypersensitivity reactions to aprotinin may occur, especially on re-exposure. Tranexamic acid can reduce blood transfusion in cardiac surgery, liver transplantation and total knee arthroplasty surgery with a satisfactory safety profile. Epsilon aminocaproic acid has not been investigated adequately, despite its widespread use. While rFVIIa may be beneficial in controlling massive coagulopathic bleeding in trauma and surgical patients, there is currently no evidence to support its prophylactic use in elective surgical patients.

Conclusion

Aprotinin and tranexamic acid are valuable pharmacologic options for reducing surgical bleeding. The expected benefit of these drugs is highly dependent on the actual blood usage for a given procedure at the institutional level. More studies using clinically significant endpoints are necessary to assess the relative efficacy and optimal dosing of these drugs.

  相似文献   
43.
44.
We report an unusual case of chronic subdural haematoma (CSH) associated with cerebrospinal fluid (CSF) rhinorrhoea emphasizing the importance of managing both conditions simultaneously. A 59- year-old man presented with watery discharge from the right nostril, of 2 months duration. MRI of the brain showed a CSH in the left fronto-parietal region with significant mass effect. There was an arachnoidocoele with a defect in the planum sphenoidale. He first underwent a burr hole evacuation of the CSH following which the CSF rhinorrhea did not subside, even with bed rest. Transnasal endoscopic closure of the CSF dural fistula was done. On the first post-operative day, he was disoriented and a CT scan showed a recollection of the subdural haematoma that required repeat evacuation. The patient was asymptomatic at discharge. To our knowledge this is the first reported case of CSF rhinorrhoea associated with CSH. Simultaneous closure of the CSF dural fistula at the time of evacuation of a coexisting CSH would be the optimal management.  相似文献   
45.
Weight loss after gastric bypass procedures has been well studied, but the long-term metabolic sequelae are not known. Data on bone mineral density (BMD), calcium, parathyroid hormone, and vitamin D were collected preoperatively and at yearly intervals after gastric bypass procedures. A total of 230 patients underwent preoperative BMD scans. Fifteen patients were osteopenic preoperatively, and three patients subsequently developed osteopenia postoperatively within the first year. No patient had or developed osteoporosis. At 1 year, total forearm BMD decreased by 0.55% (n = 91; P = .03) and radius BMD had increased overall by 1.85% (n = 23; P = .008); both total hip and lumbar spine BMD decreased by 9.27% (n = 22; P < .001) and 4.53% (n = 31; P < .001), respectively. By the second postoperative year, BMD in the total forearm had decreased an additional 3.62% (n = 14; P<.001), whereas radius BMD remained unchanged. Although total hip and lumbar spine BMD significantly decreased at 1 year, by year 2 both total hip and lumbar spine BMD only slightly decreased and were not significantly different from before the operation. Serum calcium decreased from 9.8 mg/dL to 9.2 during the first year (not significant [NS]) and then to 8.8 (NS) by the second year. Parathyroid hormone increased from 59.7 pg/mL (nl 10-65 pg/mL) preoperatively to 63.1 during year 1 (NS) and continued to increase to 64.7 by year 2 (NS). No difference was noted among levels of 25-hydroxy vitamin D preoperatively (25.2 ng/mL; nl 10-65 ng/mL), at 1 year (34.4), and at 2 years (35.4). Our data indicate that bone loss is highest in the first year after gastric bypass with stabilization, and that, in some cases, there is an increase in bone density after the first year. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation).  相似文献   
46.
During embryonic development, morphogenetic gradients can specify the formation of gene expression territories. Here, we explore possible commonalities between pattern formation in the Drosophila blastoderm and murine pituitary. Shared principles include the need for positive feedback involving fate-determining genes to maintain a differentiated state, and the existence of intra- or extracellular inhibitory signals that improve spatial resolution of neighboring territories. The precision of spatial segregation is, however, limited by stochastic gene expression. Variability in gene expression at territory boundaries might give rise to a poorly differentiated pool of cells, which could harbor stem-like properties. The ideas outlined here deserve further theoretical and experimental exploration.  相似文献   
47.
48.
The inducible nature of the immediate-early genes (IEGs) c-fos and zif268 allows their products to be used as activity markers in the brain. The utility of such markers in general is restricted because they can resolve only neurons activated by a single stimulus. To overcome this limitation, we have developed a double-label technique that exploits the dissimilar time course of zif268 mRNA and protein induction, allowing them to be separately induced by two different stimuli and independently stained to provide a visual display of neurons that are responsive to each stimulus. Two powerful features of this new imaging technique—the possibility of staining separate populations of activated neurons and the ability to visualize them at the cellular level—should extend IEG applications in biological activity mapping.  相似文献   
49.
Infectious intracavernous carotid artery aneurysms usually present with ophthalmoplegia and/or signs of cavernous sinus thrombosis. We report an unusual case in which a patient with AIDS presented with intractable epistaxis secondary to rupture of a giant infectious intra-cavernous carotid artery aneurysm. Culture of the aneurysm grew mycobacterium avium intracellulare (MAI). The patient was treated successfully by excision of the aneurysm and reconstruction of the internal carotid artery with a saphenous vein interposition graft.  相似文献   
50.
BACKGROUND AND OBJECTIVES: The aim of this study was to compare in a prospective nonrandomized study, the efficacy of 2 methods of administering methotrexate (MTX) in the treatment of ectopic pregnancy (EP): transvaginal injection under sonographic control or intramuscular injection (IM). METHODS: Patients with EP who met specific inclusion criteria for medical treatment were treated with MTX: 63 patients (group 1) were treated by IM and 47 patients (group 2) by transvaginal local injection. In group 1, 50 mg/m2 of MTX was injected intramuscularly; in group 2, transvaginal injection of 1 mg/kg of MTX was injected into the ectopic sac under sonographic control. When an additional dose of MTX was required, it was administrated IM at the dosage of 50 mg/m2 in both groups. RESULTS: The overall success rate, defined by a posttreatment normal hCG level (< 10 mUI/mL) was 71.4% in group 1 versus 91.5% in group 2 (P < 0.01); for patients with hCG levels < 2000 mUI/mL, 83% and 96%, respectively (not significant); for patients with hCG > or = 2000 mUI/mL, 37.5% and 86.4%, respectively (P < 0.01). CONCLUSION: In the medical treatment of EP, the efficacy of MTX is greater when administered by local transvaginal injection than by IM injection. We propose local treatment every time EP can be punctured, especially when hCG levels are > or = 2000 mUI/mL.  相似文献   
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