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41.
An 82-year-old man with hypothyroidism presented with an ulcerated nodule on the dorsum of his left hand (Figure 1). The lesion had been present for about 3 months. Similar lesions were present along the lymphatic distribution of the dorsum of his left forearm, proximal to the first lesion, as well as the dorsum of his right forearm. Laboratory findings were normal. Immune complexes, complement 3, and complement 4 were negative. A biopsy from an ulcerated nodule was taken for both histologic examination and culture. Hematoxylin and eosin sections showed a nonspecific chronic granulomatous reaction. No fungi were detected by periodic acid-Schiff stain and methenamine silver stain. Culture of tissue obtained from a skin biopsy of 1 lesion placed directly on Sabouraud agar produced colonies of Sporothrix schenckii (Figure 2). The diagnosis of lymphocutaneous sporotrichosis was confirmed.  相似文献   
42.
To investigate a possible antinociceptive role of serotonin receptor subtype 3 (5-HT(3)), we evaluated the effects of a coadministration of ondansetron, a 5-HT(3) selective antagonist, and tramadol, a central analgesic dependent on enhanced serotonergic transmission. Fifty-nine patients undergoing ear, throat, and nose surgery, using tramadol for 24-h postoperative patient-controlled analgesia (bolus = 30 mg; lockout interval = 10 min) were randomly allocated either to a group receiving ondansetron continuous infusion (1 mg. mL(-1). h(-1)) for postoperative nausea and vomiting (Group O) or to a control group receiving saline (Group T). Pain and vomiting scores and tramadol consumption were evaluated at 4, 8, 12, and 24 h. Pain scores were never >4, according to a 0-10 numerical rating scale, in both groups. Group O required significantly larger doses of tramadol at 4 h (213 versus 71 mg, P < 0.001), 8 h (285 versus 128 mg, P < 0.002), and 12 h (406 versus 190 mg, P < 0.002). Vomiting scores were higher in Group O at 4 h (P < 0.05) and 8 h (P = 0.05). We conclude that ondansetron reduced the overall analgesic effect of tramadol, probably blocking spinal 5-HT(3) receptors. IMPLICATIONS: Serotonin is an important neurotransmitter of the descending pathways that down-modulate spinal nociception. In postoperative pain, ondansetron, a selective 5-HT(3) receptor antagonist, increased the analgesic dose of tramadol. We suggest that, when antagonized for antiemetic purpose, 5-HT(3) receptors foster nociception, because of their site-dependent action.  相似文献   
43.
BACKGROUND: Despite its common acceptance in clinical practice, the effective benefits of normothermic systemic perfusion during coronary artery bypass operations are far from established. METHODS: A total of 113 patients undergoing primary isolated coronary artery bypass were randomly assigned to normothermic (37 degrees C) or hypothermic (26 degrees C) systemic perfusion. The clinical course of the patients was prospectively recorded, and several inflammatory and fibrinolytic markers (C-reactive protein, fibrinogen, interleukin 6, plasminogen activator inhibitor 1, prothrombin time, activated partial thromboplastin time, platelets, and white blood cell counts) were determined before surgical intervention; 24, 48, and 72 hours thereafter; and at hospital discharge. RESULTS: Postoperatively, 2 in-hospital deaths occurred in the normothermic series and none in the hypothermic series. Four patients had a myocardial infarction, 1 had respiratory insufficiency, 1 had to be reoperated on for graft malfunction, and none had renal insufficiency in the hypothermic group versus 1 patient with each of these complications in the normothermic series. Mean blood loss in the first 24 hours was 766 +/- 223 mL in the normothermic group and 740 +/- 220 mL in the hypothermic group. None of these differences was statistically significant. Similarly, no significant difference in the postoperative level of any of the measured variables at any time point was evident between the patients in the normothermic and hypothermic groups. CONCLUSION: Normothermic systemic perfusion does not influence the clinical course or the extent of inflammatory and hemostatic activation in patients undergoing primary isolated coronary artery bypass.  相似文献   
44.
BACKGROUND: Cold preservation produces hepatic injury that is difficult to assess during early reperfusion. The value of reperfusion plasma choline phospholipid in predicting subsequent organ function is documented in these studies. MATERIALS AND METHODS: Livers of female Yorkshire pigs were prepared for transplantation. After 2 h of cold ischemia the reperfusion plasma was evaluated for choline phospholipid and cholesterol. These values were correlated with bile secretion, hepatic hemodynamics, oxygen uptake, and plasma sorbitol dehydrogenase levels. RESULTS: The isolated porcine liver demonstrates a rapid efflux of choline phospholipids into plasma during early reperfusion after cold preservation. After this initial efflux no subsequent plasma increment occurred. These choline-phospholipid increments were isolated in plasma higher density (d > 1.063) lipoproteins and were not accompanied by equivalent increases in cholesterol. Neither biliary reflux nor lecithin cholesterol acyl transferase abnormalities contributed appreciably to the phospholipid increments in reperfusion plasma. Livers with the largest efflux of choline phospholipids had the most impaired circulatory and bile secretory function at 4 h of reperfusion. CONCLUSION: The immediate increase of choline phospholipids, particularly lysophosphatidylcholine, in reperfusion plasma after cold ischemia provides an index of the injury occurring during this interval and correlates with early organ function.  相似文献   
45.
Minimally invasive video-assisted thyroidectomy: multiinstitutional experience   总被引:29,自引:3,他引:29  
Minimally invasive video-assisted thyroidectomy (MIVAT) was described in 1998. In this study we collected the experience of four third-level referral centers that adopted this technique. A total of 336 patients (279 females, 57 males) were selected for MIVAT. Selection criteria were thyroid volume <15 ml, nodules not exceeding 3.5 cm of diameter, and an absence of thyroiditis, previous neck surgery, or previous irradiation. The procedure, totally gasless, is carried out through a 15 mm central incision above the sternal notch. Dissection is performed under endoscopic vision using conventional and endoscopic instruments. The mean operating time was 69.4 ± 30.6 minutes for lobectomy (range 20–150 minutes) and 87.4 ± 43.5 minutes for total thyroidectomy (range 30–220 minutes). The mean postoperative stay was 1.9 ± 0.8 days. Postoperative complications were 7 transient and 1 definitive recurrent nerve palsies and 11 cases of hypoparathyroidism (9 transient, 2 definitive). Conversion to open surgery was necessary in 15 patients (4.5%). This study confirms in a large number of cases the safety and feasibility of MIVAT, even in different surgical settings where similar results were achieved. The complication rate was not different from that of standard thyroidectomy. Although the operating time appears longer than with conventional procedures, the learning curve demonstrates a sharp decrease with increasing experience and the introduction of new technologies. The number of patients eligible for this approach remains low, thereby limiting its use, but it should be considered a valid option in selected surgical centers, offering some advantages to patients in terms of cosmetic results and postoperative distress.  相似文献   
46.
Total thyroidectomy is not frequently performed in cases of benign disease because of the associated risk of postoperative hypoparathyroidism and recurrent laryngeal nerve (RLN) damage. We chose a series of patients who had undergone total thyroidectomy (TT) for benign thyroid tumors to evaluate the safety of this approach and its role in the treatment of nonmalignant lesions of the thyroid. We considered only patients with a minimum follow-up of 24 months. Records of 526 patients who underwent TT were carefully reviewed, assessing for perioperative complications and late sequelae. The mean age was 44 +/- 15.7 years; 109 patients (20.7%) were male and 417 (79.3%) were female. Altogether, 65 patients (12.3%) were operated on for toxic goiter, 429 (81.6%) for bilateral nodular goiter, and 32 (6.1%) for thyroiditis. Postoperative hemorrhage requiring reoperation occurred in 8 cases (1.5%). The incidences of permanent RLN palsy (considered as a percentage of the nerves at risk) and permanent hypocalcemia were 0.4% and 3.4%, respectively. A trend toward a decrease in the complication rate was observed during the last 5 years. There were no disease recurrences during a mean follow-up of 44 months. The results of our series show that TT can be performed safely in patients, with a low incidence of lifetime disabilities. TT has the advantage of reducing/avoiding the risk of disease recurrence and reoperation and should therefore be considered a valuable option for treating benign thyroid diseases.  相似文献   
47.
We measured bone density (BD) changes to assess adaptive bone remodelling five years after uncemented total hip arthroplasty with taper-design femoral component using quantitative computed-tomography-assisted osteodensitometry (qCT). Nineteen consecutive patients (21 hips) with degenerative joint disease were enrolled in the study. A press-fit cup and a tapered uncemented stem ceramic−ceramic pairing were used in all patients. Serial clinical, radiological and qCT osteodensitometry assessments were performed after the index operation and at the one, two and five year follow-ups. At the latest follow-up, the clinical outcome was rated satisfactory in all hips. The radiological assessment showed signs of osteointegration with stable fixation of all cups and stems. Overall, there was evidence of a BD loss at year five (p = 0.004). We estimate that BD loss was between 2.2% and 12.1% in comparison with baseline postoperative values. Progressive loss of BD in the metaphyseal region was observed in all hips. We found unremarkable BD changes of diaphyseal cortical BD throughout the five year follow-up period. qCT osteodensitometry technology allows differentiation of cortical and cancellous BD changes over time. Periprosthetic BD changes at the five year follow-up are suggestive of stable stem osteointegration with proximal femoral diaphysis load transfer and metaphyseal stress shielding.  相似文献   
48.

Background

Multiple studies have reported favorable short-term outcomes using tantalum cones to reconstruct massive bone defects during revision TKA. However, longer-term followup is needed to determine the durability of these reconstructions.

Questions/purposes

We wished to determine the mid-term (1) reoperation rates for septic and aseptic causes, (2) radiologic findings of osseointegration, and (3) clinical outcomes based on the Knee Society score in patients who underwent revision knee arthroplasty with tantalum cones for severe bone loss.

Methods

We retrospectively evaluated records of 18 patients (18 knees) who underwent revision knee arthroplasty with use of tantalum cones between 2005 and 2008; the primary indications for use of this approach were to reconstruct massive bone defects classified as Anderson Orthopaedic Research Institute Types 2B and 3. During this period, all defects of this type were treated with this approach and no cones were used for more-minor defects. A total of 26 cones (13 tibial and 13 femoral) were implanted. There were 12 female and six male patients with a mean age of 73 years (range, 55–84 years) at the time of revision. The indication for the revision included aseptic loosening (five patients) and second-stage reimplantation for deep infection (13 patients). Patients were followed for a mean of 6 years (range, 5–8 years). No patient was lost to followup. Clinical and radiographic outcomes were assessed with the Knee Society clinical rating system and radiographic evaluation system.

Results

There have been two reoperations for recurrent infection; at surgery, the two cones showed osseointegration. No evidence of loosening or migration of any implant was noted on the most recent radiographs. Knee Society knee scores improved from a mean of 31 points before surgery to 77 points at latest followup (p < 0.001), and function scores improved from a mean of 22 points to 65 points (p < 0.001).

Conclusions

Tantalum cones for reconstruction of massive bone defects in revision knee arthroplasty provided secure fixation with excellent results at average followup of 6 years, although this series included relatively few patients. These devices are a viable option for surgeons to use in situations with severe bone loss. Further studies with longer followups are needed to confirm the durability of these reconstructions.

Level of Evidence

Level IV, therapeutic study.  相似文献   
49.
50.
Expression of carbonic anhydrase 9 at the invasion front of gastric cancers   总被引:5,自引:0,他引:5  
BACKGROUND: Carbonic anhydrase IX (MN/Ca9) catalyses the reversible metabolism of carbon dioxide to carbonic acid and has also been linked to malignant transformation and hypoxia in various cancers. AIMS: To assess the expression and biological role of Ca9 in gastric cancer. METHODS: Using gastric cancer cell lines and tissues, we studied expression of Ca9 by western blot analysis, immunohistochemistry, and polymerase chain reaction. Biological changes after Ca9 transfection and after treatment with 5'-azadeoxycytidine were also analysed in cancer cell lines. RESULTS: Non-cancerous tissues strongly expressed Ca9 with membranous localisation. In contrast, Ca9 expression was frequently lost in gastric cancers (p<0.001). However, gastric cancers that retained Ca9 expression in cancer cells exhibited a shorter postoperative survival (p = 0.028). In vitro analysis revealed that loss of Ca9 expression in gastric cancer cell lines was restored after treatment with 5'-azadeoxycytidine and was associated with increased invasion (p<0.01). Moreover, AGS cells transfected with Ca9 exhibited significantly increased cell proliferation (p<0.05). CONCLUSIONS: A subgroup of gastric cancers retain Ca9 expression in cancer cells at the invasion front. While loss of Ca9 expression is regulated in part by methylation, re-expression of Ca9 is associated with increased invasion, supporting the hypothesis that increased Ca9 expression may contribute to invasion and thus advanced disease and tumour progression in a subset of gastric cancers.  相似文献   
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