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971.
Osteoid osteoma of the cervical spine depicted as dumbbell tumor by MRI   总被引:2,自引:0,他引:2  
We report a case of 14-year-old male patient with osteoid osteoma of the cervical spine. Magnetic resonance imaging (MRI) revealed a large dumbbell-shaped paravertebral tumor in the region of the exiting left C6 nerve. A computed tomographic (CT) scan after myelography showed a much smaller bony defect in the medial aspect of the left C6 pedicle with central calcification and extensive bone sclerosis around the defect, typical of osteoid osteoma. The diagnosis was confirmed postoperatively. The resected specimen exhibited extensive vascularization of the osteoid tissue. The case is presented because MRI did not allow a specific diagnosis of osteoid osteoma, and suggested the tumor was larger than in reality it was, by also depicting the reactive inflammation around the tumor as if it were part of the tumor. Received: 12 October 1999/Revised: 7 February 2000/Accepted: 23 February 2000  相似文献   
972.

Study Objective

To investigate the effect of intravenous (IV) landiolol, a novel β1-adrenergic blocker, on the minimum alveolar concentration (MAC) of sevoflurane in adult women.

Design

Prospective, randomized study.

Setting

University hospital.

Patients

42 ASA physical status 1 and 2 women, aged 24-57 years, who were scheduled to undergo elective abdominal surgery.

Interventions

Anesthesia was induced in all patients by vital capacity rapid inhalation induction of sevoflurane. In the landiolol group, administration of landiolol began when patients took a vital-capacity breath: 0.125 mg/kg/min for one minute and then 0.04 mg/kg/min. Normal saline was administered in the control group.

Measurements

MAC was determined by a technique adapted from the conventional up-down method.

Main Results

The MAC of sevoflurane was 2.2% ± 0.2% in the control group and 1.7% ± 0.2% in the landiolol group, a statistically significant difference (P = 0.0005).

Conclusions

IV landiolol reduces the MAC of sevoflurane in women by approximately 20%.  相似文献   
973.
We previously reported that a toll‐like receptor 4 signaling contributes to the development of osteonecrosis of the femoral head. Also, oxidative stress is suggested to be one of the possible pathogenesis of osteonecrosis of the femoral head. A recent study showed that toll‐like receptor 4 signaling leads to oxidative stress. The aim of the present study was to evaluate whether toll‐like receptor 4 stimulation and subsequent corticosteroid treatment lead to the development of osteonecrosis of the femoral head in rat, and oxidative stress is associated with it. Male Wistar rats were randomly divided into four treatment groups: Saline + Saline, Saline + Methylprednisolone, Lipopolysaccharide + Saline, Lipopolysaccharide + Methylprednisolone. Osteonecrosis of the femoral head at 14 days after the treatment was observed in 1 of 10 Lipopolysaccharide + Saline, and 5 of 10 Lipopolysaccharide + Methylprednisolone treated rats. However, it was not observed at all in the Saline + Saline and Saline + Methylprednisolone treated groups. Glutathione peroxidase activity in the liver at 1 day after the treatment was significantly increased when treated with lipopolysaccharide. However, methylprednisolone treatment reduced the activity. On the other hand, glutathione peroxidase activity in the femur did not change in any intergroup. In conclusion, the present study showed that toll‐like receptor 4 stimulation by lipopolysaccharide administration strengthen incidence of corticosteroid‐induced osteonecrosis of the femoral head, however, concomitant oxidative stress via toll‐like receptor 4 signaling may not contribute to the development of osteonecrosis of the femoral head in rats. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:342–345, 2016.  相似文献   
974.

Purpose

The purpose of this study was to investigate the relationship between the blood levels of interleukin (IL)-18 measured in the early stage of acute respiratory failure and the prognosis for patient survival.

Methods

The study subjects were 38 patients with acute respiratory failure treated at our institution during the 4-year period from April 2004 to March 2008. The underlying clinical condition was defined as acute respiratory distress syndrome (ARDS; n?=?12) or acute lung injury (ALI; n?=?26). The serum levels of interleukin (IL)-18, IL-12, and tumor necrosis factor (TNF)-α were measured by enzyme-linked immunosorbent assays.

Results

The ARDS group showed significantly higher serum levels of IL-18, IL-12, and TNF-α even at an early stage after disease onset compared with the ALI group. A negative correlation was noted between the PaO2/FIO2 ratio (P/F ratio) and serum IL-18 level. Analysis of all 38 patients with ALI/ARDS revealed a 30-day mortality rate of 7.9?%, 60-day mortality rate of 15.8?%, and 90-day mortality rate of 18.4?%. The early-stage serum levels of IL-18, IL-12, and TNF-α were significantly higher in the non-survivors at 60 and 90?days, but not at 30?days, than in the corresponding survivors.

Conclusion

The present data demonstrate an inverse correlation between serum IL-18 level and the P/F ratio, suggesting the possible involvement of IL-18 in the pathogenesis of respiratory failure in patients with ALI/ARDS. Early-stage serum IL-18, IL-12, and TNF-α levels appear to reflect the >60-day prognosis in patients with ALI/ARDS.  相似文献   
975.
Pneumoperitoneum (PP) is usually the result of perforation of the gastrointestinal (GI) tract with associated peritonitis. However, other rare causes, including spontaneous PP incidental to intrathoracic, intra-abdominal, gynecologic, and miscellaneous other origins not associated with a perforated GI tract have been described in the literature. Six cases of PP without any perforated GI tract are reported. Three patients with generalized peritonitis underwent exploratory laparotomy or laparoscopy when clinical examinations suggested an acute abdomen. At surgical procedure, perforated pyometra, perforated liver abscess and a ruptured necrotic lesion of a liver metastasis were documented in these patients, respectively. We also saw 3 PP patients not associated with peritonitis. Two patients with PP caused by pneumatosis cystoides intestinalis were encountered, 1 was managed conservatively and the other received diagnostic laparoscopy. A patient in whom pneumomediastinum and pneumoretroperitoneum were accompanied by PP caused by an alveolar rupture based on decreased pulmonary compliance due to malnutrition was managed conservatively. The history of the patient and knowledge of the less frequent causes of PP can possibly contribute towards refraining from exploratory laparotomy in the absence of peritonitis.  相似文献   
976.
Liposarcoma is a one of the common soft tissue sarcomas, and is estimated to represent 16–18% of sarcomas in adults. According to the World Health Organization, this tumor is mainly classified into five subtypes: well-differentiated, dedifferentiated, myxoid/round, pleomorphic and mixed-type. Previous papers have reported that radiological information for liposarcoma is correlated with the radiological and histopathological findings. In liposarcoma, when biphasic patterns composed of a lipogenic tumor with a sarcomatous appearance are found on radiological examination of computed tomography and/or magnetic resonance imaging, dedifferentiated liposarcoma, defined as a “malignant adipocytic neoplasm showing transition from atypical lipomatous tumor/well-differentiated liposarcoma to non-lipogenic sarcoma of variable histological grade”, is usually considered.  相似文献   
977.
AIM: We investigated the extent of apoptosis in crypt cells and Peyer's patches (PPs) during small bowel allograft rejection in rats to examine the effect of FTY720 during rejection. METHODS: Orthotopic small bowel transplantations (SBTs) were performed from BN to LEW rats. Isografted animals served as controls. Three groups of SBT animals were studied on days 3, 5, and 7 after operation: isograft, untreated allograft, allograft with FTY720. FTY720 was orally administered by gavage (1 mg/kg/d) to allograft recipients on 7 consecutive days. Cryostat sections were prepared from grafts, including PPs. An in situ end-labeling (ISEL) technique was used to detect apoptotic cells. Indirect immunoperoxidase staining was also performed using monoclonal antibodies against rat Fas/Fas-L. RESULTS: Graft survival was prolonged in the FTY720-treated group. The number of ISEL-positive enterocytes in the allografts increased significantly on days 3, 5, and 7 compared with the isograft group. In the FTY720-treated group, the number of ISEL-positive enterocytes in the allografts was down-regulated significantly on days 3, 5, and 7 compared with untreated allograft group. In the PPs, the number of ISEL-positive mononuclear cells increased significantly in the allografts compared with the isograft group. In the FTY720-treated groups, the number of ISEL-positive mononuclear cells were down-regulated significantly in the allografts compared with the untreated allograft group. The number of Fas/FasL-positive enterocytes were increased significantly in allografts compared with isograft group. In FTY720-treated groups, the number of Fas/FasL-positive enterocytes were down-regulated significantly on day 7 compared with the untreated allograft group. In the PPs, Fas/FasL-positive mononuclear cells also increased significantly on day 7 in the allografts compared with isografts. In the FTY720-treated groups, Fas/FasL-positive mononuclear cells were down-regulated significantly in the allografts compared with the untreated allograft group. CONCLUSIONS: The number of apoptotic enterocytes, lymphocytes, and Fas/FasL-positive lymphocytes increased during small bowel graft rejection. FTY720 prevented up-regulation of the number of apoptotic enterocytes, lymphocytes, and Fas/FasL-positive lymphocytes while also prolonging small bowel allograft survival.  相似文献   
978.

Purpose

The treatment guidelines for isolated superior mesenteric artery (SMA) dissection have not been established. We assessed 14 cases of SMA dissection and reviewed the literature on this entity.

Methods

The subjects were 11 men and 3 women (average age 64 years), with SMA dissection diagnosed by computed tomography (CT) scan or digital subtraction angiography, between 2001 and 2009, at our institution. Eight patients presented with symptoms such as abdominal pain, but SMA dissection was diagnosed incidentally during investigations of another illness in six patients. Thirteen patients were treated conservatively with anticoagulation and/or antiplatelet drugs, but one underwent exploratory laparotomy. The median follow-up period was 22 months.

Result

The symptoms did not worsen, and ultimately resolved in the eight patients who had symptoms. Isolated dissection improved dramatically in two of the six patients with obstruction of the false lumen and was not seen on computed tomography (CT) scans 1 and 3 months after its onset.

Conclusion

We recommend conservative treatment as the first choice for isolated SMA dissection, even if the patient has abdominal pain and tenderness, given that there are no signs of peritonitis.  相似文献   
979.
980.
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