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61.
Yeh SY 《Synapse (New York, N.Y.)》1999,31(3):169-177
The present study examined the effect of N-tert-butyl-alpha-phenylnitrone (PBN) on 3,4-methylenedioxmathamphetamine (MDMA)-induced depletion of serotonin in the CNS. Rats were treated with two concurrent injections of MDMA (20 mg/kg, s.c.), PBN (50-400 mg/kg dissolved in ethanol, 50 mg/ml of 25% ethanol, i.p.), saline or 25% ethanol, alone or in combination, 6 h apart, and sacrificed 5 days later. Rectal temperature was measured prior to and hourly following the drug injection for 5 h. Monoamine levels in the tissue were measured by HPLC. Density of the 5-HT transporters was assayed by [3H]paroxetine binding. Rectal temperature of rats increased after MDMA, decreased after PBN, ethanol, PBN plus ethanol, and MDMA plus ethanol, and was not significantly altered after MDMA plus PBN. Levels of 5-HT and 5-HIAA in the frontal cortex, hippocampus, striatum, and brain stem of rats decreased significantly after MDMA or MDMA plus ethanol, but not after MDMA plus PBN, PBN plus ethanol (PBN dissolved in ethanol), or ethanol as compared to the saline controls. Levels of 5-HT and 5-HIAA in the brain tissues of rats treated with MDMA plus PBN were elevated as compared to those treated with MDMA plus saline. Similar results were observed in the density of 5-HT transporters in the frontal cortex and hippocampus. These results indicate that scavenging of free radicals of MDMA metabolites or reactive oxygen species by PBN and with lowering of body temperature protected against MDMA-induced depletion of serotonin transmitter. 相似文献
62.
Liver resection for hepatocellular carcinoma in octogenarians 总被引:4,自引:0,他引:4
BACKGROUND: Liver resection is risky in patients aged > or = 80 years. Because of short life expectancies and improved nonoperative modalities, the role of liver resection in octogenarians with hepatocellular carcinoma (HCC) is unclear. METHODS: A retrospective review of the operative results of 260 patients with HCC between 1991 and 1997 was performed. According to the age at the time of operation, these patients were divided into 2 groups. Group 1 comprised 21 patients aged > or = 80 years, and group 2 comprised the other 239 younger patients. The backgrounds, pathologic features of the tumor, and operative results of the patients were compared. RESULTS: Octogenarians had a higher incidence of associated medical diseases, a higher incidence of negative serum hepatitis B surface antigen, a lower alpha-fetoprotein level, and a higher indocyanine green retention rate. Although octogenarians had a longer postoperative hospital stay, there were no significant differences between the 2 groups regarding operative morbidity and mortality. The 5-year disease-free and actuarial survival rates for octogenarians and younger patients were 50.6% and 35.3% (P = .15) and 40.9% and 59.3% (P = .46), respectively. CONCLUSION: Under meticulous preoperative assessments and postoperative care, liver resection for HCC is justified in selected octogenarians, with short- and long-term results comparable to those of younger patients. 相似文献
63.
Knee dislocation: treatment of high-velocity knee dislocation 总被引:9,自引:0,他引:9
BACKGROUND: We report the outcomes of patients treated with a new arthroscopic treatment modality for knee dislocation after high-velocity trauma. METHODS: Twenty-three patients (12 men, 11 women; 25 knees) with traumatic knee dislocation were treated with this technique. Under arthroscopy with gravity inflow irrigation, the ruptured posterior cruciate ligament was reconstructed with a patellar bone-tendon-bone graft, and the anterior cruciate ligament was debrided subacutely. The collateral ligament, meniscus, and capsules were repaired through additional incisions. RESULTS: The average interval between injury and surgery was 11.1+/-5 days (range, 5 to 25 days). After a mean follow-up period of 27.2+/-7.86 months, the mean extension was 1+/-2 degrees and the average flexion was 129.6+/-4.91 degrees. The mean Lysholm score was 84. There were no major complications. CONCLUSION: Arthroscopic posterior cruciate ligament reconstruction seems to be an effective treatment for traumatic knee dislocation. 相似文献
64.
Acute liver failure includes a constellation of clinical conditions resulting from rapid loss of hepatocyte function. The anesthesiologist may often be asked to anesthetize a patient with acute liver failure before the etiological entity of disease can be completely clarified. Most of the previous reports were concentrated in obstetric or hepatological periodicals. Reports about anesthesia for such patients are scanty. We present a case about a near term pregnant woman with a complication diagnosed as impending acute liver failure, who received total intravenous anesthesia for emergent cesarean section. Pros and cons of different anesthetic techniques for this condition are discussed. 相似文献
65.
Interleukin 3 enhances cytotoxic T lymphocyte development and class I major histocompatibility complex "re-presentation" of exogenous antigen by tumor-infiltrating antigen-presenting cells.
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B A Pulaski K Y Yeh N Shastri K M Maltby D P Penney E M Lord J G Frelinger 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(8):3669-3674
We show that interleukin 3 (IL-3) enhances the generation of tumor-specific cytotoxic T lymphocytes (CTLs) through the stimulation of host antigen-presenting cells (APCs). The BALB/c (H-2d) spontaneous lung carcinoma line 1 was modified by gene transfection to express ovalbumin as a nominal "tumor antigen" and to secrete IL-3, a cytokine enhancing myeloid development. IL-3-transfected tumor cells are less tumorigenic than the parental cell line, and tumor-infiltrating lymphocytes isolated from these tumors contain increased numbers of tumor-specific CTLs. By using B3Z86/90.14 (B3Z), a unique T-cell hybridoma system restricted to ovalbumin/H-2b and implanting the tumors in (BALB/c x C57BL/6)F1 (H-2d/b) mice, we demonstrate that the IL-3-transfected tumors contain an increased number of a rare population of host cells that can process and "re-present" tumor antigen to CTLs. Electron microscopy allowed direct visualization of these host APCs, and these studies, along with surface marker phenotyping, indicate that these APCs are macrophage-like. The identification of these cells and their enhancement by IL-3 offers a new opportunity for tumor immunotherapy. 相似文献
66.
A 22-year-old man with malignant immunoblastic lymphoma had "locked-in" syndrome within 48 hours of receiving a single (100 mg) dose of intrathecal cytosine arabinoside (ara-C) in conjunction with intravenous ara-C, cisplatin, and doxorubicin. Eight hours after therapy, the patient had central hypoventilation and blurred vision that progressed to blindness within 3 hours. During the next 10 hours, he became completely quadriplegic but remained intermittently alert and was able to respond to commands by eye or head movements. Radiographic studies showed necrosis of the medulla and swelling of the entire spinal cord. The patient persisted in a locked-in state until his death 3 weeks later, after removal of life support systems. Autopsy confirmed extensive necrosis of the lower medulla, optic chiasm, cranial nerves I and IV, and spinal cord. This case was unusual for its severity. The temporal relationship to ara-C instillation favors a toxic idiosyncratic response to chemotherapy. The authors advocate caution when bolus intrathecal and intravenous ara-C are administered to a patient within a short time of each other. 相似文献
67.
The so-called hypertrophic column of Bertin is a normal variation and simply represents unresorbed polar parenchyma of one or both of the two subkidneys that fuse to form a normal kidney. It contains renal cortex, pyramids, and columns (septa) of Bertin. (Since all elements of the tissue are normal, that is, neither hypertrophic nor a displaced or embryonic rest, it is referred to as "junctional parenchyma.") When a masslike lesion is suspected at sonography or excretory urography, diagnosis of junctional parenchyma can be made with a high degree of certainty when sonography shows that the structure (a) is located between the overlapping portion of two renal sinus systems, (b) is bordered by a junctional parenchymal line and defect, (c) contains renal cortex, pyramids, and columns of Bertin, and (d) contains renal cortex that is continuous with the adjacent renal cortex of the same subkidney. 相似文献
68.
Hypotension is an uncommon complication of procedures involving extracorporeal circulation, including plasmapheresis. From November 1993 to March 1999, we treated 139 patients who underwent a total of 1,137 sessions of double filtration plasmapheresis (DFP). Hypotension was defined as a systolic blood pressure (BP) < 80 mm Hg or any decrease of systolic BP with systemic reactions. A total of 17 (1.5%) episodes of hypotension were documented in 15 patients during the study period. Hypotensive episodes occurred in 2.3% of patients with inflammatory neuropathy, 1.2% of patients with myasthenia gravis, and 1.2% of patients with all other medical diseases. Involvement of the autonomic nerve system (ANS) and a low baseline BP were associated with the occurrence of hypotension. Eight (47%) of 17 episodes were symptomatic and 2 were complicated with seizure. Patients with symptomatic hypotension had a higher level of systolic BP prior to DFP and a larger drop of systolic BP and pulse rate during hypotensive attacks compared to asymptomatic patients. Most hypotensive episodes were resolved briefly after intravenous infusion of saline within 30 min. Eight (47%) of the hypotensive episodes occurred during the first session of DFP treatment. Twelve (71%) of 17 episodes occurred during the last half period of treatment; 6 of them were noted during the terminating stage of DFP. In conclusion, in this series plasmapheresis-related hypotension occurred in 1.5% of DFP sessions and had a higher prevalence in patients with ANS instability and low BP. Extra caution in monitoring BP during DFP therapy is warranted in these vulnerable patients, especially during the termination phase of the first DFP session. 相似文献
69.
70.
Jun-Jun Yeh Wu-Huei Hsu We-Tao Huang Jhi-Joung Wang Shung-Tai Ho Albert Kao 《Tumour biology》2003,24(3):151-155
The multidrug resistance gene 1 encoding human P-glycoprotein (Pgp) is thought to play an important role in the multidrug resistance of lung cancer. The purpose of this study was to predict chemotherapy response by technetium-99m tetrofosmin (Tc-99m TF) lung single photon emission computed tomography (SPECT) and compare Pgp expression in patients with untreated small cell lung cancer (SCLC). Forty patients with untreated SCLC received Tc-99m TF lung SPECT prior to chemotherapy. The chemotherapy response was evaluated in the 3rd month after completion of treatment. Immunohistochemical staining of Pgp expression was performed on multiple nonconsecutive sections of biopsy specimens. By quantitative analyses, tumor to background ratios were 1.86 +/- 0.27 and 1.17 +/- 0.26 for patients with a good and poor response, respectively (p < 0.05). All of the 20 patients with a good chemotherapy response also had a positive Tc-99m TF lung SPECT and negative Pgp expression. In contrast, only 4 of the 20 patients with a poor chemotherapy response had a positive Tc-99m TF lung SPECT. Moreover, 10 of the 20 patients with a poor chemotherapy response also had negative Pgp expression (p < 0.05). Therefore, we concluded that Tc-99m TF lung SPECT can accurately predict the chemotherapy response, and Tc-99m TF lung SPECT findings can be partially compatible with Pgp expression in patients with untreated SCLC. 相似文献