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71.
蛋白激酶C在远程预处理诱导脊髓缺血耐受中的作用   总被引:2,自引:0,他引:2  
目的:探讨蛋白激酶C在下肢缺血预处理诱导脊髓缺血耐受效应中的作用.方法:实验于2004-07/12在解放军兰州军区乌鲁木齐总医院临床实验室进行.取28只雄性新西兰大白兔,随机分成4组(n=7):①对照组:阻断肾下腹主动脉20min,制作兔脊髓缺血模型.②预处理组:用充气式压力止血带阻断双下肢腘窝上1/3,压力200mmHg(1 mmHg=0.133 kPa),循环两次,每次10 min,间隔10 min,最后一次处理后30 min同前造摸.③拮抗剂组:静脉给予蛋白激酶C拮抗剂chelerythrine 5mg/kg,1 h后造模.④预处理加拮抗剂组:预处理前30 min静脉注射chelerythrine 5 mg/kg,余同预处理组.再灌注后4,8,12,24和48h分别对动物后肢运动功能评分(Tarlov标准,0~4级,共5级,0级为后肢完全瘫痪,4级为运动功能正常).再灌注48 h,处死动物取脊髓(L5~7),计算脊髓前角正常神经元数.结果:经补充后28只动物进入结果分析.①脊髓前角正常神经元数:预处理组显著高于对照组、拮抗剂组和预处理加拮抗剂组(69,12,12,8个,P<0.01).②神经功能评分:预处理组在再灌注8 h后各时间点均明显高于对照组(P<0.01),预处理加拮抗剂组和拮抗剂组与对照组比较差异无显著性(P>0.05).③神经功能评分与脊髓前角正常运动神经细胞数之间有显著相关性(r=0.872,P<0.01).结论:蛋白激酶C拮抗剂chelerythrine能完全阻断下肢预处理对随后脊髓缺血的保护效应,提示蛋白激酶C参与了远程预处理诱导脊髓缺血耐受的形成机制.  相似文献   
72.
OBJECTIVE: To compare the risk of ovarian failure and the fertility of women treated with intravenous cyclophosphamide (IVCY) according to the underlying inflammatory disease. METHODS: Review of the data of 84 consecutive women: 56 with systemic lupus erythematosus (SLE), 28 with other diseases, mainly Wegener's granulomatosis and systemic vasculitides. RESULTS: The mean age at IVCY initiation was 29 +/- 10 years (range 13-53). The mean dosage was 0.9 +/- 0.14 g per pulse (range 0.5-1), and the mean number of pulses 13 +/- 6.5 (range 3-42). With a mean followup of 5.1 +/- 3.7 years, 23 women developed amenorrhea, with a mean duration of 4 +/- 3.6 months between IVCY initiation and amenorrhea. Amenorrhea was sustained in 19 women (13 with SLE and 6 with other diseases, NS). The mean age at ovarian failure onset was 40 +/- 7.6 years. The risk of ovarian failure correlated with the age at IVCY institution (p < 0.0001), and was independent of underlying inflammatory disease. Eighteen women (13 with SLE and 5 with other diseases) became pregnant during or after CY therapy, with a total of 22 pregnancies. The mean age at IVCY initiation, and the mean number of IVCY (maximum 40 pulses) before pregnancy were similar in women with SLE and those with other diseases. Six pregnancies occurred during IVCY therapy, which ended in induced abortion (n = 3), spontaneous abortion (n = 1), and normal pregnancy after IVCY withdrawal (n = 2) in women who wished to keep their pregnancy despite the risk of teratogenicity. Sixteen pregnancies occurred 2.9 +/- 2.1 years (range 1-9) after IVCY withdrawal. They ended in: 3 induced abortions indicated for severe morphological anomalies (n = 2) and for SLE relapse (n = 1), 3 spontaneous miscarriages, and 10 deliveries of healthy newborns. CONCLUSION: The risk of ovarian failure depends essentially on the age at IVCY initiation. Pregnancy may occur during IVCY therapy, and an efficient contraception is mandatory. After IVCY withdrawal, pregnancy is possible with a favorable outcome in two-thirds of the cases.  相似文献   
73.
SETTING: Reported tuberculosis (TB) cure rates are high in Vietnam with the 8-month short-course chemotherapy regimen. However, long-term treatment outcomes are unknown. OBJECTIVE: To assess survival and relapse rates among patients successfully treated for new smear-positive pulmonary tuberculosis (PTB). METHODS: A cohort of patients treated in 32 randomly selected districts in northern Vietnam were followed up 12-24 months after reported cure or treatment success for survival and bacteriologically confirmed relapse. Measurements included sputum smear examination, culture and interview for recent treatment history. RESULTS: Of 304 patients included in the study, no information was available for 31 (10%) and 19 (6%) had died. Bacteriology results were available for 244 (80%). The median interval between treatment completion and follow-up was 19 months. Relapse was recorded in 21/244 (8.6%, 95%CI 5.4-13), including 9 (4%) with positive sputum smears, 3 (1%) with negative smears but positive culture and 9 (4%) who had started TB retreatment. Four of 12 culture-positive relapse cases (33%) had multidrug-resistant strains. If the definition of relapse was extended to include death, reportedly due to TB, the relapse proportion was 26/263 (9.9%, 95%CI 6.6-14). CONCLUSION: A substantial proportion of patients (15%) had died or relapsed after being successfully treated for TB in northern Vietnam.  相似文献   
74.
Improvement in the prognosis of SLE prognosis has led to considering infertility therapy. The earliest reports displayed complications such as SLE revealed by ovulation induction or thrombophlebitis. Fertility is known to be normal in women with SLE, excepting amenorrhea accompanying severe flare-ups, renal insufficiency-related hypofertility and ovarian failure secondary to cyclophosphamide therapy. Anti-phospholipid antibodies are suspected to cause defective nidation and placental ischemia. An exponential rise of serum estradiol is observed irrespective of the ovulation induction protocol used, leading to SLE flare-up and thrombosis. We have experience with 114 cycles in 21 women with SLE and/or APS. A complication (fetal loss, SLE flare-up, thrombophlebitis) revealed the underlying disease in 8 women. Eighteen pregnancies led to 9 live-births, 4 fetal deaths and 5 embryonic losses. Pregnancy rate was higher after ovulation induction using gonadotropins (25% per cycle), than clomiphene (4%). Pregnancy rate was similar after IVFETE, whether the protocol was planned or not. However, three-quarters of the pregnancies after unplanned IVFETE led to abortions. On the contrary, 6 out of 7 pregnancies after planned IVFETE led to live-births. Two women developed thrombophlebitis after gonadotropins therapy. A SLE flare-up appeared after 13 out of 62 cycles, with a flare-up rate higher after gonadotropins (27% per cycle) than clomiphene therapy (6%), and after an unplanned (30%) than a planned procedure (10%). In conclusion, ovulation induction therapy can reveal SLE or APS. Clomiphene complications are uncommon. When gonadotropin therapy is considered, a preventive anti-inflammatory therapy should be discussed in SLE patients, in conjunction with heparin and/or anti-aggregate therapy for those with asymptomatic anti-phospholipid antibodies or prior thrombotic events.  相似文献   
75.
OBJECTIVE: Viruses might be one of the elements that trigger systemic lupus erythematosus (SLE). Steroid therapy may influence the natural history of virus infections. The most frequent extrahepatic manifestations of hepatitis C virus (HCV) including arthralgia, myalgia, sicca syndrome, and antinuclear antibodies, may mimic a connective tissue disease, particularly SLE. Reports on the association between SLE and HCV infection are scarce. We investigated the association of HCV infection and SLE. METHODS: Retrospective case-control monocentric study of 19 patients with SLE and anti-HCV antibodies versus 42 randomized SLE patients without anti-HCV antibodies, matched for age and sex, coming from our cohort of 700 patients with SLE. SLE and HCV-infection features were reviewed. RESULTS: Mode of infection was blood product transfusion, drug addiction, or unknown. Prevalence of lupus clinical manifestations, antinuclear, anti-dsDNA, anti-extractable nuclear antigen antibodies, and complement levels was not different between HCV positive and negative SLE patients. Prevalence of cryoglobulin was higher in SLE patients with anti-HCV antibodies (p < 0.04), but none had a mixed cryoglobulinemia syndrome. ALT activity was increased in 11 HCV positive patients and 13 had detectable HCV RNA. Liver biopsy showed cirrhosis in 2 and mild fibrosis and activity in 5. One patient treated with interferon-alpha had a sustained virological response without SLE flare. Steroid therapy did not seem to alter HCV course. CONCLUSION: SLE in HCV positive patients shows higher prevalence of cryoglobulin without mixed cryoglobulinemia syndrome. HCV infection has moderate signs of biochemical and liver pathological severity. SLE by itself or treated with steroids does not seem to worsen HCV infection.  相似文献   
76.
Volume replacement was studied prospectively in 208 infants with dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). The mean volume of intravenous fluid used was 110.4 mL/kg administered over a mean period of 25.8 hours. The mean volumes of intravenous fluid replacement in infants with DSS was significantly higher than in those with non-shock DHF (129.8 mL/kg versus 102.1 mL/kg; P = 0.001). Patients with DSS had significantly higher proportional requirements for dextran and blood transfusions than non-shock infants. Recurrent shock, prolonged shock, and acute respiratory failure were recorded in 8, 6, and 13 patients, respectively. Four patients with DSS died of severe complications. Intravenous fluid replacement with special care to avoid fluid overload requires careful attention to established indications for use of colloidal solutions and blood transfusions. To improve case fatality rates, special efforts need to be directed to infants with DHF/DSS accompanied by severe complications.  相似文献   
77.
SETTING: Six provinces in Vietnam where the DOTS strategy was introduced in 1989. OBJECTIVE: To assess the impact of improved tuberculosis (TB) control on TB epidemiology in Vietnam. METHODS: Data from the surveillance system in the period 1990-2003 were analysed to assess trends of notification rates and the mean ages of notified cases. Data from repeated tuberculin surveys in the period 1986-2002 were estimated to assess the prevalence of TB infection, the annual risk of infection and its trend using various cut-off points in those with and without bacille Calmette-Guérin (BCG) scar. RESULTS: Age-standardised notification rates in the period 1996-2003 declined significantly, by 2.6% to 5.9% per year, in five provinces. However, in four provinces notification rates in the age group 15-24 years increased significantly, by 4.5% to 13.6% per year, during this period. The mean age of newly diagnosed patients with smear-positive TB increased up to 1995 but decreased thereafter. The annual risk of TB infection showed a significant annual decrease (4.9% per year) in one province in surveys performed between 1986 and 1997, and in two provinces (6.6% and 4.7%) in surveys conducted between 1993 and 2002. CONCLUSION: These data suggest limited impact to date of the DOTS strategy in Vietnam.  相似文献   
78.

Background

As impairment of diffusing capacity for carbon monoxide (DLCO) likely reflects underlying pulmonary vasculopathy in limited systemic sclerosis (lSSc), we examined whether DLCO could help to distinguish secondary from idiopathic Raynaud's phenomenon (iRP).

Methods

We compared pulmonary function test (PFT) results in 145 lSSc patients and 24 age- and sex-matched iRP patients. RP duration at time of PFT was similar in the two groups.

Results

DLCO values were low (< 80% of predicted) in 106 (73%) of the 145 lSSc patients, and in 69 (71%) of the 97 patients with early lSSc. Interstitial lung disease (ILD) was found in 10% of lSSc patients. DLCO was significantly lower in lSSc than in iRP (72 ± 15% versus 89 ± 9%, p < 0.0001). When evaluated, alveolar capillary membrane conductance (Dm) was markedly lower in lSSc patients without ILD than in iRP patients (45 ± 12% versus 71 ± 2.5%, p = 0.003), although capillary blood volume was not different. DLCO was low in 3 iRP patients (12.5%). The sensitivity and specificity of low DLCO values for early lSSc diagnosis in patients with Raynaud's phenomenon were 71% and 87.5%, respectively. Sensitivity was similar to that of anti-centromere-antibodies (75%) and nailfold capillary abnormalities (81%). A DLCO cutoff of < 70% had a sensitivity and specificity of 41% and 100%, respectively.In multivariable analysis, age and low DLCO were the only independent predictors of death; the hazard ratio for DLCO ≤ 50% was 7.9 (95% CI 2.3-26, p = 0.0007).

Conclusion

Isolated DLCO impairment is significantly more frequent in patients with lSSc than in patients with idiopathic iRP. DLCO measurement could be a useful diagnostic tool for lSSc.  相似文献   
79.
In this paper, we address the issues of shortage and maldistribution of health personnel in southeast Asia in the context of the international trade in health services. Although there is no shortage of health workers in the region overall, when analysed separately, five low-income countries have some deficit. All countries in southeast Asia face problems of maldistribution of health workers, and rural areas are often understaffed. Despite a high capacity for medical and nursing training in both public and private facilities, there is weak coordination between production of health workers and capacity for employment. Regional experiences and policy responses to address these challenges can be used to inform future policy in the region and elsewhere. A distinctive feature of southeast Asia is its engagement in international trade in health services. Singapore and Malaysia import health workers to meet domestic demand and to provide services to international patients. Thailand attracts many foreign patients for health services. This situation has resulted in the so-called brain drain of highly specialised staff from public medical schools to the private hospitals. The Philippines and Indonesia are the main exporters of doctors and nurses in the region. Agreements about mutual recognition of professional qualifications for three groups of health workers under the Association of Southeast Asian Nations Framework Agreement on Services could result in increased movement within the region in the future. To ensure that vital human resources for health are available to meet the needs of the populations that they serve, migration management and retention strategies need to be integrated into ongoing efforts to strengthen health systems in southeast Asia. There is also a need for improved dialogue between the health and trade sectors on how to balance economic opportunities associated with trade in health services with domestic health needs and equity issues.  相似文献   
80.
INTRODUCTION: The cytomegalovirus (CMV) infection is most often asymptomatic. The grave forms concern the immunocompromised patients. We report a new case pf acute CMV hepatitis complicated with portal thrombosis in an immunocompetent patient. EXEGESIS: A 29 year old man has presented a CMV hepatitis proved by the presence of pp65 protein and the viral DNA in serum. This infection was complicated by a portal thrombosis and the evolution was rapidly favourable under anticoagulant treatment. Eleven cases of major thrombosis complicating acute CMV infection in immunocompetent patients were previously reported in the English and French literature. The absence of local and general cause, the remission without anticoagulation, the elevated risk of thrombosis in both HIV and CMV seropositive patients, and in CMV seropositive renal transplant patients suggest a causal relation. Various pathogenic hypotheses were raised: presence of antiphospholipid antibodies, absent in our case, procoagulant phenotype induction of infected endothelial cells, proliferation induction of smooth cells. CONCLUSION: The acute CMV infection can be considered such as a possible cause of major thrombosis.  相似文献   
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