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101.
杀菌性通透性增强蛋白对失血性休克的保护作用及其机理 总被引:2,自引:0,他引:2
分别在失血和复苏开始即刻iv杀菌性/通透性增强蛋白(BPI)1.5和3.5mgkg-1,观察BPI对大鼠失血性休克转归的影响.结果显示,BPI治疗能明显改善失血性休克大鼠肝肾功能,提高休克动物存活率(BPI组81%vs休克对照组44%,P<0.05),BPI组大鼠复苏后与休克前的血浆内毒素(0.20±0.04vs0.24±0.05kUL-1)水平无明显变化,血浆肿瘤坏死因子α和白介素6水平较休克前明显升高,但均显著低于休克对照组.提示BPI对失血性休克大鼠具有一定的保护作用,其机理可能与BPI拮抗休克时内源性内毒素活性,抑制细胞因子反应有关. 相似文献
102.
Carol A. Sawka Kathleen I. Pritchard Wendy Shelley Gerrit DeBoer Alexander H.G. Paterson J. William Meakin Donald J.A. Sutherland 《Breast cancer research and treatment》1997,43(3):211-215
Background: The outcome of breast cancer is usuallydetermined by multiple factors. Serum tumor necrosis factoralpha concentration has been found to be increasedin the circulation of patients with malignancy. Thisstudy was designed with the aim to investigateany correlation between the serum tumor necrosis factoralpha and the clinicopathological fetures and furthermore evaluatethe prognostic significance of serum tumor necrosis factoralpha concentration in breast cancer. Methods: Forty consecutivepatients with invasive breast cancer undergoing modified radicalmastectomy were prospectively included and evaluated. Venous bloodsamples were collected before the surgery. Sera wereobtained by centrifugation, and stored at – 70°C until assayed. The control group consisted 30healthy, age-matched subjects. Serum concentrations of tumor necrosisfactor alpha were measured by the quantitative sandwichenzyme immunoassay technique. The data on tumor size,age, estrogen receptor status, lymph node status andTNM staging were reviewed and recorded.Results: The mean value of serum tumor necrosis factor alphain patients with invasive breast cancer was 1.47± 0.58 pg/ml and that of the controlgroup was 0.98 ± 0.37 pg/ml, and thedifference was significant (P < 0.01). With univariableanalysis, patients with maximum tumor size of 5cm or larger (P=0.03), more advancedTNM staging (P < 0.01); and more advancedlymph node status (P < 0.01) were shownto have significantly higher serum concentrations of tumornecrosis factor alpha. However, with multivariable analysis, TNMstaging appeared as the only independent factor (P< 0.01) predicting the significant, higher serum concentrationsof tumor necrosis factor alpha. Conclusion: Preoperative evaluationof serum tumor necrosis factor alpha concentrations maybe a valuable parameter for reflecting the severityof staging for invasive breast cancer. 相似文献
103.
Splanchnic ischaemia and its role in multiple organ failure 总被引:3,自引:0,他引:3
Multiple organ failure remains the leading cause of death in the intensive care unit. Increasing numbers of investigators have focused their attention on the role of gastrointestinal tract in the pathogenesis of this syndrome. Their data indicate that inadequate gut perfusion leads to a measurable imbalance between oxygen delivery and the needs of the tissues, i.e., ischaemia. Gut ischaemia of sufficient duration impairs gastrointestinal tract barrier function, facilitating the passage of enteric bacterial endotoxin into the circulation. It has been hypothesized that production of tumor necrosis factor α, and other biologic mediators by endotoxin–stimulated macrophages, triggers a generalized and uncontrolled inflammatory response that ultimately leads to multiple organ failure.
Preliminary evidence suggests that survival can be improved significantly if gut ischaemia is promptly identifed and aggressively treated by administration of fluids and inotropic drugs, using gastric intramucosal pH as the therapeutic endpoint. Future studies are needed to determine whether additional treatment modalities can improve outcome once the inflammatory response has fully developed. 相似文献
Preliminary evidence suggests that survival can be improved significantly if gut ischaemia is promptly identifed and aggressively treated by administration of fluids and inotropic drugs, using gastric intramucosal pH as the therapeutic endpoint. Future studies are needed to determine whether additional treatment modalities can improve outcome once the inflammatory response has fully developed. 相似文献
104.
105.
B. Pfausler G. Grubwieser S. Bsch H. Vollert M. Herald E. Schmutzhard 《European journal of neurology》1995,2(6):570-572
A 37 year old male was admitted with the diagnosis of bacterial meningitis. Pneumococci were seen in the Gram stain of the cerebrospinal fluid. The clinical condition did not suggest severely raised intracranial pressure, there were no localizing signs and symptoms. CSF was turpid, with 20.100/3/mm3, mainly polymorphonuclear cells. Tumor necrosis factor alpha in CSp was greatly increased with 813 pg/ml. Parallel to the application of intravenous Penicillin G a CSF filtration was carried out. Within 214 h 225 ml CSF were filtrated through a Pall-filter, using a bidirectional pump. Cell count dropped to 720/3 cells/mm3, TNF-alpha to 39 pg/ml. The clinical course was uneventful, on day 12 the patient could be discharged without sequelae. CSF filtration may be a highly effective method to reduce from the CSF pathogenetically important cytokines, such as TNF-alpha, being responsible for intrathecal/meningeal inflammatory processes and triggered by cell-wall components of bacteria, e.g. pneumococci. 相似文献
106.
A.V. Chistyakov J.F. Soustiel H. Hafner M. Elron M. Feinsod 《Acta neurochirurgica》1998,140(5):467-462
Summary
This study attempts to find out whether the motor evoked potential (MEP) elicited by single pulse and slow-rate (1 Hz) repetitive
transcranial magnetic stimulation (TMS) can disclose concealed subclinical impairments in the cerebral motor system of patients
with minor head injury.
The motor response to single pulse TMS (STMS) of the patient groups was characterized by significantly higher threshold compared
with that of the control group. The central motor conduction time, as well as the peripheral conduction time were normal in
all patients pointing to cortical impairment.
Two main patterns of MEP changes in response to repetitive TMS (RTMS) were observed in the patient group. A. – progressive
decrease of the MEP amplitude throughout the stimulation session to a near complete abolition. B. – irregularity of the amplitude
and the waveform of the MEP in a chaotic form. The MEP latency remained stable during the whole stimulation session. The MEP
abnormalities recovered gradually over the period of a few months.
The higher threshold of the motor response to STMS and the abnormal patterns of the MEP to RTMS seem to reflect transient
impairment of cortical excitability or “cortical fatigue” in patients who sustained minor head injures. Further study is needed
to evaluated the extent and the pathophysiological mechanisms of the central nervous system fatigue phenomenon following head
injury. 相似文献
107.
Enhanced in vivo cytotoxicity of recombinant human tumor necrosis factor with etoposide in human renal cell carcinoma 总被引:1,自引:0,他引:1
Summary The combination of tumor necrosis factor (TNF) and etoposide (ETP) was evaluated for potential cytotoxic efficacy against a human renal cell carcinoma xenograft using an in vivo assay employing an athymic mouse host with tumor implanted a the subrenal capsule site. Both antitumor efficacy (relative survival or RTS) and toxicity (weight loss) of TNF and ETP alone and in combination were evaluated. While TNF and ETP alone were mildly inhibitory (RTS 90% and 71%, respectively), the combination caused marked tumor inhibition (45% of controls). Host toxicity encountered with the combination did not exceed the toxicity associated with ETP alone, suggesting that the therapeutic index may have been augmented. It is concluded that enhanced antitumor activity without substantial augmentation of toxicity is observed with this combination, providing a rationale for further evaluation of tumor necrosis factor-based regimens for the treatment of advanced renal carcinoma.Supported by a Merit Review grant, VA Medical Research Service, Durham, NC 27710, USA 相似文献
108.
非创伤性股骨头坏死患者的血液学改变 总被引:7,自引:0,他引:7
目的测定非创伤性股骨头坏死(nontraumaticosteonecrosisoffemoralhead,NONFH)患者的血液学指标变化,筛选敏感分子标记物用于早期诊断和筛选高危人群。方法研究对象共分三组:(1)NONFH早期组(塌陷前期)30例,(2)NONFH晚期组(塌陷后期)30例,(3)正常对照组30例。各组对象均抽取空腹肘静脉血。应用酶联免疫吸附法(ELISA)测定血小板α-颗粒膜蛋白(GMP-140)、血浆蛋白C(PC)、D-二聚体(D-Dimer)含量;发色底物法测定血浆纤溶酶原激活剂抑制剂(PAI)活性。结果(1)NONFH早、晚期组血小板GMP-140含量均高于正常对照组,血浆PC含量均低于正常对照组,D-Dimer含量均高于正常对照组,PAI活性均高于正常对照组(P均<0.05)。骨坏死情况越严重,各项指标上升或降低的趋势越明显,而且各项指标早、晚期组间比较差异均有显著性(P均<0.05)。(2)经判别分析,筛选出PAI、D-Dimer、PC三个指标,建立NONFH早期、晚期和正常对照三类判别函数式。NONFH早期:Y1=?26.3966 41.4916X10 0.0512X4 4.1390X1;NONFH晚期:Y2=?66.7566 82.1315X10 0.1082X4 2.7233X1;正常对照组:Y3=?26.7049 20.5695X10 0.0327X4 6.1900X1。回代判对率97.78%。结论(1)NONFH患者各期均存在高凝和低纤溶状态。(2)PAI、D-Dimer、PC为NONFH患者的血液学敏感指标。 相似文献
109.
目的 观察空心加压螺纹钉联合高压氧治疗青年股骨颈骨折的疗效.方法 56例青年股骨颈骨折患者,35例给予空心加压螺纹钉手术后联合高压氧治疗(高压氧组),21例仅用空心加压螺钉内固定手术,不进行高压氧治疗(手术组),对2组近、中、远期疗效和并发症进行比较.结果 2组近期疗效、并发症差异无统计学意义(P>0.05),高压氧组中、远期疗效及减少术后并发症方面优于手术组,2组差异有统计学意义(P<0.05).结论 闭合复位、小切口空心加压螺钉内固定联合高压氧治疗青年股骨颈骨折在中、远期疗效,减少股骨头坏死及髋关节疼痛等并发症方面有很好的疗效. 相似文献
110.
Toshikazu Tanaka Peter C Amadio Chunfeng Zhao Mark E Zobitz Kai-Nan An 《Journal of orthopaedic research》2006,24(4):757-762
While attrition from sharp bony surfaces is the most common cause of extensor digiti minimi (EDM) tendon rupture, the etiology of other cases of spontaneous EDM tendon rupture is still unknown. Friction within the compartment may play a role, especially with ulna dislocation. The purpose of this study was to compare gliding resistance of the EDM tendon with that of a tendon which rarely ruptures spontaneously, the extensor digitorum communis of the middle finger (EDC III) tendon, under various wrist and ulna head positions. Eight fresh frozen cadavers were used. Gliding resistance between the tendon and its sheath in each compartment was measured in five different wrist positions and three different ulna head positions. Gliding resistance of the EDM tendon (0.13 +/- 0.03 N) was significantly greater than the EDC III tendon (0.09 +/- 0.03 N) (p < 0.05). For the EDM tendon, the gliding resistance in ulnar deviation or pronation was higher than the gliding resistance in neutral, radial deviation, or supination (p < 0.05), and the gliding resistance with ulnar lengthening (over 6 mm) or dorsal ulnar dislocation (over 9 mm) was higher than in neutral ulnar head positioning. For the EDC III tendon, the gliding resistance in ulnar deviation was significantly higher than the gliding resistance in neutral, radial deviation, or supination, or dorsal dislocation with ulnar lengthening (p < 0.05). Wrist ulnar deviation, ulnar dorsal dislocation (over 9 mm), and ulnar lengthening (over 6 mm) increased the gliding resistance of the EDM tendon. In patients at risk for EDM rupture, such as those with rheumatoid arthritis or distal radioulnar joint osteoarthritis, avoiding such positions may be advantageous. 相似文献