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101.
Considering the proximity of the major endopelvic and exopelvic vascular structures to the hip joint, we find that reported vascular complications of total hip replacement are relatively rare. We encountered 1 case of vascular injury after primary, and 2 cases after revision, total hip arthroplasty. This stimulated us to send a postal survey to the members of the British Hip Society inquiring about such vascular complications, with a view to evaluating their incidence, management, and final outcome. We received 42 valid replies of 82 questionnaires sent. A conservative estimate from this study is 1 vascular injury in 14 consultant life years of practice. A total of 26 vascular injuries were studied in detail, which included 3 of our index cases. There were 14 cases encountered in revision hip replacement, while the rest occurred in primary hip replacement surgery. Three patterns of presentation of vascular injuries were recognized--immediate, early, and late, all of which require prompt recognition and appropriate treatment. The potential of vascular injury seems to be underestimated in primary total hip replacements, leading to late recognition and poor outcome.  相似文献   
102.
BACKGROUND: Patients with squamous carcinoma of the oral tongue in clinical stages TIN0M0 and T2N0M0 with a tumor thickness < or = 3 mm usually do not have lymph node (LN) metastasis. However, factors that are useful in predicting LN metastasis in thicker tumors (> 3 mm thick) need to be identified. The authors investigated the clinical relevance of the apoptotic index (AI), the proliferation index, and tumor grade in relation to LN metastasis in patients with early stage squamous carcinoma of the oral tongue. METHODS: Twenty-three patients with squamous carcinoma of the anterior two-thirds of the tongue measuring < 2 cm in height and > 3 mm in thickness were evaluated for tumor grade, AI (by using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling technique), and proliferation index (by proliferating cell nuclear antigen [PCNA] expression). RESULTS: The mean AI value was significantly higher in LN positive patients compared with LN negative patients (P = 0.012). The LN positive and LN negative subgroups did not differ in the mean PCNA index, and there was no significant difference in the distributions of tumor grade between LN positive and LN negative subsets. Four of 12 tumors with an AI < or = 5% and 10 of 11 tumors with an AI > 5% had LN metastasis (P = 0.009; risk ratio, 20). The AI maintained its significance with respect to LN metastasis in the multivariate analysis (P = 0.003). The 4-year recurrence free survival was significantly better in patients with tumors that had an AI value < or = 5% compared with patients with tumors that had an AI > 5% (92% vs. 32%) (P = 0.033). However, the AI lost its impact on recurrence free survival within a Cox proportional hazards model (P = 0.068). CONCLUSIONS: A higher AI value is a predictor of LN metastasis and may serve as a prognostic factor in patients with early stage squamous carcinoma of the oral tongue. The authors present a hypothesis to explain this rather surprising finding.  相似文献   
103.
Accidents with foreign bodies (FBs) are most common within the first two years of life. The airway FBs present a diagnostic dilemma as both the history and the investigations can be misleading. The persistent hypoxia presents a threat to life as does extraction. Moreover, the chemical pneumonitis induced by vegetative FB makes the situation even more worse. The FB of digestive tract are comparatively benign unless long standing. It is neither necessary for the airway FB to present with respiratory symptoms and signs nor for the FB of digestive tract to complain of dysphagia/throat pain. Oesophagoscopy may have to be done if an esophageal FB is causing only recurrent respiratory infections without dysphagia. The situation in dealing with FB varies from site to site in the aerodigestive tract. This article stresses the various dubious factors including the history, examination and investigation which can lead to misdiagnosis and also those problems which are encountered during planned extraction as well as post-operatively.  相似文献   
104.
Anaplastic thyroid carcinoma (ATC) is the most aggressive and lethal form of thyroid malignancy which is difficult to treat. At the time of diagnosis, majority of patients have distant metastases most commonly in lung, bone, and liver. However nasal tip metastasis is not reported in literature. Implantation of malignant cells on nasal tip is also unknown. We hereby report an interesting and unusual mechanism for nasal tip metastasis in a patient with ATC.  相似文献   
105.
PURPOSE: To examine the ability of contact lenses coated with fimbrolides, inhibitors of bacterial quorum sensing, to prevent microbial adhesion and their safety during short-term clinical assessment. METHODS: A fimbrolide was covalently attached to commercially available high Dk contact lenses. Subsequently Pseudomonas aeruginosa, Staphylococcus aureus, Serratia marcescens, or Acanthamoeba sp. were added to the lenses and control uncoated contact lenses. Lenses plus microbes were incubated for 24 h, then washed thoroughly to remove non-adherent microbes. Lenses were macerated and resulting slurry plated onto agar plates. After appropriate incubation, the numbers of colony forming units of bacteria (or numbers of Acanthamoeba trophozoites measured using a hemocytometer) from fimbrolide-coated and uncoated lenses were examined. A Guinea Pig model of lens wear was used to assess the safety of lenses worn on a continuous basis for 1 month. In a separate study, 10 subjects wore fimbrolide-coated lenses for 24 h. The responses of the Guinea Pigs and human volunteers to the lenses were assessed by slit lamp examination. RESULTS: The fimbrolides-coated lenses reduced the adhesion of all bacterial strains tested, with reductions occurring of between 67 and 92%. For Acanthamoeba a reduction of 70% was seen. There were no significant differences in ocular responses to fimbrolide-coated lenses compared with controls in either the 1 month animal model or overnight human trial. CONCLUSIONS: Fimbrolide-coated lenses show promise as an antibacterial and anti-acanthamoebal coating on contact lenses and appear to be safe when worn on the eye in an animal model.  相似文献   
106.
First described as a pleural neoplasm, the solitary fibrous tumor (fibrous mesothelioma) has been reported in a number of extrapulmonary sites, including the Head-Neck region. In the Head-Neck region, it has been described in the sinonasal tract, epiglottis, parapharyngeal, retropharyngeal spaces, parotid and infratemporal fossa. We present the second case of solitary fibrous tumor of infratemporal fossa described in world literature. A complete excision was achieved by transmaxillary approach.  相似文献   
107.
Fas and Fas ligand expression were investigated in twenty two cases of classical Hodgkin's disease (HD) by immunohistochemistry. While Reed-Sternberg (RS) cells in 7/22 (32%) cases expressed Fas ligand, reactive lymphoid cells expressed Fas ligand in only 2 (9%) cases. In 20/22 (91%) cases, the RS cells expressed Fas. A higher proportion of RS cells in the nodular sclerosis subtype expressed Fas as compared to the mixed cellularity subtype. In 18/22 (82%) cases, Fas expression was also noted in the reactive lymphoid cells. In eight cases, the reactive lymphoid cells were also analyzed by flow cytometry and a majority of them were CD4+CD45RO+. Most of these activated T-cells expressed Fas but were negative for Fas Ligand. To investigate the co-expression of Fas and Fas Ligand in the RS cells, six cases were subjected to Fas and Fas ligand immunostaining on consecutive sections. The co-expression was documented in the RS cells in four of six cases. These six cases with expression of both Fas and Fas ligand were investigated for the incidence of apoptosis. There was no statistically significant relationship between expression of Fas on reactive cells, expression of FasL on RS cells and the proportion of apoptotic reactive cells. In all these cases apoptosis was not observed in the RS cells. Thus Fas - FasL interactions may not lead to apoptosis of the RS cells.  相似文献   
108.
OBJECTIVE: Large-volume paracentesis is a safe and effective means of treating patients with refractory ascites. However, there is limited information regarding the need for ascitic fluid studies in asymptomatic outpatients presenting for therapeutic paracentesis. The aim of this prospective study was to define the incidence and natural history of peritoneal fluid infection in asymptomatic outpatients undergoing therapeutic paracentesis. METHODS: Over a 13-month period, 118 therapeutic paracenteses were performed in 29 outpatients with decompensated cirrhosis (Child-Pugh class B = 38%, C = 62%). After a brief medical history and physical examination, ascitic fluid cell count with differential and culture were obtained from all participating subjects. Seven (24%) of the subjects were receiving norfloxacin prophylaxis, accounting for antibiotic coverage during 40% of the procedures performed. The clinical course and outcome of study subjects during a mean follow-up of 137 days was reviewed. RESULTS: All 118 (100%) of the ascitic fluid samples demonstrated absolute neutrophil counts of <250/mm3 (mean = 6.5 +/- 22.5 pmn/mm3). Asymptomatic bacterascites was identified from three of the 118 (2.5%) fluid samples, but all of these subjects spontaneously recovered without treatment or sequelae. During follow-up, six episodes of symptomatic or hospital-associated peritoneal fluid infection were identified in study participants, emphasizing the importance of fluid studies in other clinical settings. CONCLUSIONS: Although further studies are needed, the routine culture of ascitic fluid in asymptomatic outpatients with refractory ascites requiring therapeutic paracentesis may not be necessary when there is a low index of suspicion for occult infection. In circumstances of clinical uncertainty, however, obtaining ascitic fluid cell counts with differential is recommended to insure patient safety.  相似文献   
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