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991.
Thromboembolism constitutes one of the most dangerous complications during the immediate postoperative period of prosthetic surgery. Pharmacological prophylaxis and mechanical vascular compression are not always sufficient to protect from this surgical complication. In patients at greatest risk for thromboembolism, often with a positive history for pulmonary embolism, temporary vena cava filters may be used to reduce the incidence of vascular and pulmonary complications. However useful, these filters cannot be routinely used in orthopedic surgery. We present our results with the use of Filcard RFO2 vena cava filters in an open, randomized study of 30 patients. Received: 5 November 2001/Accepted: 30 November 2001  相似文献   
992.

Background

This study was undertaken to evaluate the accuracy of touch preparation (touch prep) in the evaluation of sentinel lymph nodes (SLNs).

Methods

We performed a retrospective review of 402 breast cancer patients who underwent SLN biopsy.

Results

A SLN was identified in 381 patients. Of 61 patients with a true positive result, 59 underwent axillary node dissection, and in 22 the SLN was the only node with metastases. Thirty-six (9.44%) had at least 1 false negative result. Twenty-five with a false negative results were due to macrometastases, with 17 (2.4%) false negatives occurring in patients with invasive ductal and 6 (5.5%) in those with invasive lobular histology, P = .04. Touch prep had an overall sensitivity of 62.89% and specificity of 98.94%.

Conclusions

Touch prep for the evaluation of SLNs in breast cancer compares favorably to reported results for frozen section. False negative findings are more likely with micrometastases and invasive lobular histology.  相似文献   
993.
The aim of this study was to investigate the microleakage in class V cavities restored with four conventionally setting glass ionomers (CGIs) and one resin-modified glass ionomer (RMGI) following erbium:yttrium–aluminium–garnet (Er:YAG) laser or conventional preparation. Four hundred class V cavities were assigned to four groups: A and B were prepared by an Er:YAG laser; C and D were conventionally prepared. In groups B and D, the surface was additionally conditioned with Ketac conditioner. Each group was divided into five subgroups according to the glass ionomer cement (GIC) used: groups 1 (Ketac Fil), 2 (Ketac Molar), 3 (Ionofil Molar), 4 (Ionofil Molar Quick) and 5 (Photac Fil Quick). After thermocycling, a 2% methylene blue solution was used as dye. Scanning electron microscope (SEM) photographs were taken to show the conditioner’s effect. Complete marginal sealing could not be reached. PhotacFil showed less microleakage than the conventionally setting glass ionomer cements (CGICs) investigated. Conditioning laser-prepared cavities did not negatively influence microleakage results except for Ionofil Molar Quick.  相似文献   
994.
The incidence of gastrointestinal complications in renal transplant recipients is relatively high while about 10% is related to acute abdomen. Data concerning gastrointestinal (GI) complications were reported in literature mainly from referral center studies. A multicenter retrospectively survey was performed in Lazio, Italy, in order to evaluate the incidence of acute abdomen in renal transplant recipients observed to the emergency departments of not referral transplantation centers. Clinical and demographic findings regarding 14 patients who experienced acute abdomen between February 2005 and Dicember 2008 have been collected. The following data was investigated: etiology, diagnostic workup, duration of symptoms, elapsed time between admission and emergency operation if performed, morbility and mortality. The severity of disease at presentation was assessed by mean of the Acute Physiology and Chronic Health Evaluation score (APACHE II). Acute abdomen was due to pancreatitis in three patients (23.1%); to cholecystitis in three (23.1%); to acute diverticolitis with colon perforation in two patients (15.4%); to acute appendicitis in two (15.4%) and to intestinal obstruction in 2 patients (15.4%). Small bowel perforation was observed in two patients (15.4%) which one case, upon pathological examination, showed malignant lymphoma. The mean APACHE II score was 14.0 ± 5.9. Ten patients (71.4%) were submitted to surgery. Overall mortality and morbidity were 35% and 42% respectively. Statistical analysis showed admission APACHE II score (p<0.01), duration of symptoms (p<0.05), and total time elapsed between the onset of symptoms and treatment (p<0.04) as factors significantly related to mortality.  相似文献   
995.
We examined the distribution of quantitative heel ultrasound (QUS) parameters in population samples of European men and looked at the influence of lifestyle factors on the occurrence of these parameters. Men aged between 40 and 79 years were recruited from eight European centers and invited to attend for an interviewer-assisted questionnaire, assessment of physical performance, and quantitative ultrasound (QUS) of the calcaneus (Hologic; Sahara). The relationships between QUS parameters and lifestyle variables were assessed using linear regression with adjustments for age, center, and weight. Three thousand two hundred fifty-eight men, mean age 60.0 years, were included in the analysis. A higher PASE score (upper vs. lower tertile) was associated with a higher BUA (β coefficient = 2.44 dB/Mhz), SOS (β = 6.83 m/s), and QUI (β = 3.87). Compared to those who were inactive, those who walked or cycled more than an hour per day had a higher BUA (β = 3.71 dB/Mhz), SOS (β = 6.97 m/s), and QUI (β = 4.50). A longer time to walk 50 ft was linked with a lower BUA (β = ?0.62 dB/Mhz), SOS (β = ?1.06 m/s), and QUI (β = ?0.69). Smoking was associated with a reduction in BUA, SOS, and QUI. There was a U-shaped association with frequency of alcohol consumption. Modification of lifestyle, including increasing physical activity and stopping smoking, may help optimize bone strength and reduce the risk of fracture in middle-aged and elderly European men.  相似文献   
996.

Background

After a brain biopsy, the genetic analysis can fail because of insufficient material, extensive tumor necrosis, and formalin fixation under conditions that adversely affected the quality of the DNA or because the assay result was indeterminant. The freezing of fresh tumor tissue at surgery could greatly improve the success of DNA extraction and methyl guanine methyl transferase (MGMT) promoter methylation testing. The concentration of the DNA samples can also be improved from a withdrawal in an area with a high probability of neoplastic cells.

Methods

The present study reports the results of ten frameless image-guided intracranial needle biopsies from April 2008 until February 2009, among a total of 28 frameless neuronavigation brain biopsy performed from May 2007 to February 2009. The protocol sampling provided withdrawal specimens correlated with neuroimaging characteristics of the lesions. The molecular determination of MGMT promoter was assessed with the nested methylation-specific polymerase chain reaction on fresh or cryopreserved needle bioptic tissue.

Results

The genetic characterization was feasible in all the bioptic samples. The MGMT promoter was methylated in six patients, including a brain infection. The image-guided trajectory of the biopsy and the intraoperative frozen section increased the diagnostic yield.

Conclusions

To the best of the authors' knowledge, this is the first report with the MGMT promoter status analysis on needle bioptic fresh tissue. In the future, the availability of the molecular genetic characterization of a brain tumor before open surgery will provide important information for the optimal treatment.  相似文献   
997.
Sacroiliitis on conventional radiography, a key diagnostic feature of axial spondyloarthritis (SpA), often appears only late in the disease course. With the introduction of potent biologic agents that may also be effective in early disease, diagnostic techniques that can identify SpA early in the disease course would be highly beneficial to patients. MRI has been proposed as a novel diagnostic tool for early axial SpA based on the visualization of active inflammatory lesions in established axial SpA, as well as in pre-radiographic axial SpA. Accordingly, MRI is already widely used in clinical practice and has been included in new classification criteria. However, the specificity and predictive value of MRI lesions for the development of axial SpA remain to be fully defined and validated. Most data come from cross-sectional analyses and have not been validated in prospective studies, and the few available prospective studies were performed in highly selected patient populations and have assessed the value of MRI for the prediction of sacroiliitis rather than axial SpA. Also, some studies have indicated considerable diversity in the pattern and extent of MRI lesions, and suggest that many lesions are not specific for SpA. Prospective, longitudinal studies are needed to validate the utility of this new imaging modality for the diagnosis of axial SpA.  相似文献   
998.
We evaluated the results of the arthroscopic Outerbridge-Kashiwaghi procedure in a retrospective review of 20 elbows in 19 patients with a mean followup of 2 years (range : 6 months - 4 years). Range of motion improved from 94 degrees (range: 15 degrees-140 degrees) to 123 degrees (range: 110 degrees-140 degrees). Visual analogue scales for pain improved from 5.8 (range: 2 -8) to 1.8 (range: 0-8). The Mayo Performance Index increased from 54 (range: 15-85) to 88 (range: 45-100). The results were good to excellent in 16 elbows, fair in two and poor in two. Seventeen patients were better (85%), 3patients remained unchanged (15%). In elbows with severe arthritis, pain relief was minimal. The arthroscopic Outerbridge-Kashiwaghi procedure appeared in this study as a good surgical option in mild to moderate elbow arthritis, with significant pain relief and increased elbow mobility and function.  相似文献   
999.
After kidney transplantation, thrombotic microangiopathy (TMA) can occur de novo or as recurrent disease. Risk factors for de novo posttransplant TMA include ischemia-reperfusion injury, immunosuppressive drugs, viral infections, acute humoral rejection, and complement gene abnormalities. Cytomegalovirus infection as a trigger for posttransplant TMA in kidney transplant recipients has only been reported in 7 cases, all of them between 4 weeks and 8 years after transplantation. We describe a new case of de novo TMA in association with cytomegalovirus infection 25 years after kidney transplantation.  相似文献   
1000.
In this paper, we used repetitive transcranial magnetic stimulation (rTMS) in 18 normal subjects to investigate whether the ventral posterior parietal cortex (PPC) plays a causal role on visuospatial attention and primary consciousness and whether these 2 functions are linearly correlated with each other. Two distinct experimental conditions involved a similar visual stimuli recognition paradigm. In "Consciousness" experiment, number of consciously perceived visual stimuli was lower by about 10% after rTMS (300 ms, 20 Hz, motor threshold intensity) on left or right PPC than after sham (pseudo) rTMS. In "Attentional" Posner's experiment, these stimuli were always consciously perceived. Compared with sham condition, parietal rTMS slowed of about 25 ms reaction time to go stimuli, thus disclosing effects on endogenous covert spatial attention. No linear correlation was observed between the rTMS-induced impairment on attention and conscious perception. Results suggest that PPC plays a slight but significant causal role in both visuospatial attention and primary consciousness. Furthermore, these high-level cognitive functions, as modulated by parietal rTMS, do not seem to share either linear or simple relationships.  相似文献   
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