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1.
A 14 year old girl with double outlet right ventricle, left isomerism, and complicated atrial anatomy had undergone corrective surgery with intra-atrial rerouting at 5 years of age. Cardiac catheterisation eight years after the surgery showed that she had two systemic venous baffle stenoses: between the hepatic vein and caval vein, and the caval vein and right atrium. Two Palmaz stents were successfully implanted percutaneously through a long sheath and a balloon catheter. The stenoses were relieved immediately and her symptoms quickly disappeared.  相似文献   
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Adenovirus-mediated gene transfer into the brain is associated with significant inflammation and activation of anti-vector and anti-transgene immune responses that curtail the gene delivery of adenoviruses and therapeutic efficacy. Elucidating the molecular mediators of inflammatory and immune responses to adenoviruses injected into the brain should allow us to inhibit their inflammatory actions, thereby reducing vector clearance and enhance adenoviral-mediated gene transfer into the CNS. Cytokines are primary mediators of the immune response and are released during inflammation. Here we report for the first time that injection of replication-deficient adenovirus vectors into the cerebral ventricles of rats causes a rapid increase in body temperature. This fever response precedes any vector-encoded transgene expression and occurs with vectors encoding no transgene, as well as with vectors encoding a therapeutic transgene i.e., HSV1-thymidine kinase. No fever is detected after infection of the striatum, an important brain target in studies on neurodegeneration. After infection of the brain ventricles, CSF levels of immunoreactive tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta increase significantly (up to 300-fold). In the hypothalamus, the locus of thermoregulation in the brain, only IL-1beta and IL-6 are significantly elevated. A neutralizing TNF-alpha antibody has no effect on adenovirus-induced fever. However, pretreatment with either the IL-1 receptor antagonist or the cyclooxygenase inhibitor flurbiprofen completely abolishes adenovirus-induced fever, suggesting that IL-1 and prostaglandins are direct mediators of this response. These results are the first to demonstrate that IL-1, but not TNF-alpha, is the main mediator of a very early inflammatory response to adenovirus in the brain.  相似文献   
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(GN Nettest)  一、GPRS简介  通用分组无线服务 ( GPRS)系统扩展了当前世界上最流行的第二代移动系统一基于语音的 GSM的应用 ,使其能够收发基于分组的数据 ;同时保留了无线接口的基本内容 ,如时分多路复用和频率分配方案 ,以使 GPRS和 GSM能够共存于同一网络上。   1 .特性  传统的 GSM拨号数据接入为用户提供了最大960 0波特的速率。GPRS能够结合多个 GSM时隙 ,在上行链路和下行链路上 ,最多可以使用八个 GSM时隙 ,提供最高 1 70 kbit/sec的带宽。此外 ,GPRS采用全新的 IP网络“一直在线”接入模式 :移动用户开…  相似文献   
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One of the main problems in the culture of Chinese Hamster Ovary (CHO) cells continues to be the inability to maintain the viability of the cultures over an extended period of time. The rapid decline in viability at the end of the culture is exacerbated by the absence of serum. In trying to reduce the extent of death in these cultures, we first tried to determine the mode of death. We found that more than 80% of the cells in a standard serum-free batch culture of CHO cells in suspension died via apoptosis--as evidenced by condensed chromatin and the appearance of a characteristic DNA ladder. Furthermore, when protein synthesis was inhibited using cycloheximide, the cells underwent rapid apoptosis indicating that death proteins were present in greater abundance than survival proteins in our CHO cells. Cell lysate from CHO cells showed evidence of cysteine protease (caspase) activity. Caspases of the Interleukin-1-beta-Converting Enzyme (ICE) family, e.g., CPP32, Mch-1, etc., have been implicated in the apoptotic process. Surprisingly, a caspase peptide inhibitor, N-benzyloxycarbonyl-Val-Ala-Asp-fluoro-methyl-ketone (z-VAD.fmk), was unable to substantially extend the life of a serum-free batch culture of CHO cells. In addition, z-VAD.fmk was only marginally able to extend viability in response to withdrawal of growth and survival factors, insulin and transferrin. In both these instances, z-VAD.fmk was able to prevent cleavage of caspase substrates, but not protect cells from death. However, we found that bcl-2 expression was able to significantly extend viabilities in CHO batch culture. Bcl-2 expression also substantially extended the viability of cultures in response to insulin and transferrin withdrawal. These results provide interesting insights into the pathways of death in a CHO cell.  相似文献   
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Central hemodynamics was studied by thermodilution in 16 patients with acquired mitral defect during surgery under conditions of hypothermia without perfusion. Cooling and surgical correction were carried out under superficial ether anesthesia with morphine and droperidol. A 28% decrease of the minute circulation volume is observed as early as under general anesthesia and at the very beginning of cooling (10.8% more); this decrease is caused by rarer heart contractions and increase of the total peripheral vascular resistance as a result of body response to cool exposure. An almost 10 degrees C drop of body temperature (to 27.2 +/- 0.2 degrees C) involves a just 13% decrease of the cardiac index in comparison with the value at the beginning of cooling. Injection of droperidol before cooling blocks the increase of the total peripheral resistance in a dose-dependent mode (about 0.13 mg/kg of droperidol is needed for sufficiently complete prevention of the increase of total peripheral resistance), and thus maintains the stroke and cardiac indexes at a sufficiently high level. Morphine (in doses of up to 2.3 mg/kg) did not bring about such an effect.  相似文献   
10.
Doxorubicin containing combination chemotherapy regimens are widely used for treatment of breast and other cancers. However, these regimens are associated with significant toxicities including myocardial dysfunction and alopecia. Analogues of doxorubicin are being developed to reduce these side effects. We conducted a Phase II trial of an anthracycline analogue, pirarubicin, administered in combination with 5-fluorouracil and cyclophosphamide every 3 weeks, as front-line chemotherapy in women with metastatic breast cancer. Patients who had received prior anthracycline therapy were excluded. The chemotherapy doses were as follows: 5-fluorouracil (500 mg/m2 on days 1 and 8), pirarubicin (50 mg/m2 on day 1), and cyclophosphamide (500 mg/m2 on day 1). Among 40 evaluable patients treated on this protocol, a major response (partial or complete remission) was observed in 26 patients (response rate, 62%; 95% confidence interval, 46-77). The median response duration was 8 months, and median survival was 16 months. Grade III/IV myelosuppression occurred in 81% of the courses. The median cumulative pirarubicin dose was 410 (range, 90-870) mg/m2. A significant decrease in left ventricular ejection fraction occurred in 12 patients (at a median cumulative pirarubicin dose of 460 mg/m2) and led to congestive heart failure in 4 of these patients (cumulative pirarubicin doses of 500, 520, 590, and 730 mg/m2, respectively). Eleven patients underwent endomyocardial biopsy, either because they experienced a drop in left ventricular ejection fraction or because they had received a cumulative pirarubicin dose of 600 mg/m2 and were still responding to the treatment. Of these, only one biopsy was found to be more than grade 1.0 (in an individual who had received a cumulative dose of 705 mg/m2). Severe alopecia occurred in two-thirds of the patients. Pharmacokinetic studies revealed a triphasic elimination of pirarubicin with alpha, beta and gamma half-lives of 0.12, 1.44, and 33.9 h, respectively. Total clearance of drug was 4.2 liters.1 h/kg while the cumulative 24-h urinary excretion was less than 10% of the administered dose. The activity of the combination appears to be similar to doxorubicin-containing regimens, while the incidence of alopecia appears to be lower than the historical experience with doxorubicin. However, cardiotoxicity remains a significant problem.  相似文献   
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