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51.
1 引言 弹簧圈栓塞最初被设计并经美国食品药品监督管理局批准用于治疗显微外科手术夹闭风险高的脑动脉瘤,但目前该方法越来越被认为是颅内动脉瘤的一线治疗方法.动脉瘤血管内治疗技术已有长足进步,新器材的研发使得以前因血管解剖结构复杂而无法填塞的动脉瘤也得以治疗,从而扩大了血管内治疗的适应证.而且,血管内弹簧圈栓塞已成为当前动脉瘤血管内治疗的主流方法;医学文献证明,在特定患者人群中,弹簧圈栓塞的转归优于外科手术夹闭[1-3].最近的一份美国心脏协会(American Heart Association,AHA)科学声明指出,对于适合治疗的脑动脉瘤,不论是血管内栓塞还是显微外科手术夹闭,均为破裂动脉瘤Ⅰ级推荐治疗方法和未破裂动脉瘤的Ⅱa级推荐治疗方法[4].在这两组患者中,治疗利大于弊.一个在血管显微神经外科、神经重症监护和介入神经外科方面有着丰富经验的多学科团队最有利于对颅内动脉瘤的处理实施最佳的技术.神经血管联合写作组此前已发表过一份联合声明,提出了有关脑血管介入治疗的培训和认证的推荐意见[5].  相似文献   
52.
目的:建立社交性应激反应问卷(RSQ-SSV)中文版,并分析其信、效度。方法:按量表翻译程序将RSQ—SSV翻译成中文,整群分层选取409名大学生进行RSQ—SSV中文版的测量。随机抽取90名学生于初评后一个月进行重测,并与美国样本进行比较。结果:RSQ-SSV中文版整个问卷的Cronbach α系数为0.88,各因子仅系数在0.73~0.81之间;重测信度为0.70;全量表的条目间平均相关系数为0.11,5因子的条目间平均相关系数在0.19~0.29之间,因子间相关系数在0.12~0.76之间;条目对因子负荷系数在0.38—0.86之间,复相关系数在0.14—0.74之间;验证性因子分析的指标:IFI为0.93,CFI为0.93,TLI为0.92,RMSEA为0.06。中国大学生样本的不随意的逃避反应因子得分高于美国大学生样本[(0.97±0.41)vs.(0.91±0.48),P=0.002],而初级亲近控制应对反应、次级亲近控制应对反应、不随意的亲近反应得分均低于美国大学生样本[(1.75±0.49)vs.(2.12±0.50)、(1.51±0.43)vs.(1.80±0.48)、(1.17±0.44)vs.(1.36±0.56),均P〈0.001]。结论:RSQ-SSV中文版具有良好的信、效度,可以试用于我国大学生社交性应激反应的测评。  相似文献   
53.
High-dose intravenous gammaglobulin (IVIgG) was given to 12 children and adults with chronic idiopathic thrombocytopenic purpura (ITP) to avoid splenectomy or because they either failed to respond to or required maintenance with high doses of steroids and/or immunosuppressives. The average platelet count increase to initial therapy was 239,500/microliters (range 23,000-790,000). A concomitant IgG Fc receptor blockade, measured by IgG-sensitized 51Cr-labeled autologous erythrocytes, was seen in 11 of 11 patients tested, both splenectomized and not splenectomized, lasting 3-4 wk. Six or more months after treatment, 2 children are in remission, 2 children and 2 adults are stable requiring no therapy with platelet counts of approximately 50,000 and 30,000, respectively, 3 children require maintenance IVIgG therapy at 2-10-wk intervals, and 1 child and 2 adults have become refractory to further IVIgG. Splenectomy was not performed in 4 children. Two adults were able to discontinue daily prednisone. The 3 patients who became unresponsive to Swiss Red Cross gamma-globulin (IgSRK) therapy did so in conjunction with a markedly elevated platelet-associated IgG and IgM. Serum IgM increased an average of 103 mg/dl after the IVIgG infusions. No significant side effects were seen.  相似文献   
54.
55.

Background

A major change has occurred in the last few years in the therapeutic approach to patients presenting with all forms of acute coronary syndromes. Whether or not these patients present initially to tertiary cardiac care centers, they are now routinely referred for early coronary angiography and increasingly undergo percutaneous revascularization. This practice is driven primarily by the angiographic image and technical feasibility. Concomitantly, there has been a decline in expectant or ischemia-guided medical management based on specific clinical presentation, response to initial treatment, and results of noninvasive stratification. This 'tertiarization' of acute coronary care has been fuelled by the increasing sophistication of the cardiac armamentarium, the peer-reviewed publication of clinical studies purporting to show the superiority of invasive cardiac interventions, and predominantly supporting (non-peer-reviewed) editorials, newsletters, and opinion pieces.

Discussion

This review presents another perspective, based on a critical reexamination of the evidence. The topics addressed are: reperfusion treatment of ST-elevation myocardial infarction; the indications for invasive intervention following thrombolysis; the role of invasive management in non-ST-elevation myocardial infarction and unstable angina; and cost-effectiveness and real world considerations. A few cases encountered in recent practice in community and tertiary hospitals are presented for illustrative purposes The numerous and far-reaching scientific, economic, and philosophical implications that are a consequence of this marked change in clinical practice as well as healthcare, decisional and conflict of interest issues are explored.

Summary

The weight of evidence does not support the contemporary unfocused broad use of invasive interventional procedures across the spectrum of acute coronary clinical presentations. Excessive and unselective recourse to these procedures has deleterious implications for the organization of cardiac health care and undesirable economic, scientific and intellectual consequences. It is suggested that there is need for a new equilibrium based on more refined clinical risk stratification in the treatment of patients who present with acute coronary syndromes.  相似文献   
56.
Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare recessive disorder resulting from mutations in the autoimmune regulator ( AIRE ) gene. There is no information on AIRE mutations in Indians. In a cross-sectional study, nine patients (eight families), from four referral hospitals in India, were studied for AIRE mutations by direct sequencing. We screened for new mutations in 150 controls by allele-specific PCR. The patients had 1–7 known components of APECED. Three patients had unusual manifestations: presentation with type 1 diabetes; chronic sinusitis and otitis media; and facial dysmorphism. All patients carried homozygous, probably recessive, AIRE mutations. Two unrelated patients from a small in-bred community (Vanika Vaisya) in south India carried an unreported missense mutation, p.V80G, in the N-terminal caspase recruitment domain. Another unique mutation, p.C302X, resulting in a truncated protein with deletion of both zinc-finger domains, was detected in a patient from Gujarat. Neither mutation was detected in controls. Other mutations, previously described in Caucasians, were: 13 base pair deletion (p.C322fsX372) in 4 (38%), and Finn-major (p.R257X) and p.R139X (Sardinian) mutation in one subject each. In conclusion, in this first series of APECED in Indians, we detected AIRE mutations previously reported in Caucasians, as well as unique mutations. Of these, p.V80G is possibly an ancestral mutation in an in-bred community.  相似文献   
57.
Marva  E; Hebbel  RP 《Blood》1994,83(1):242-249
It is hypothesized that abnormal interaction between sickle hemoglobin (HbS) and erythrocyte membrane lipid might promote deposition of denatured hemoglobin (hemichrome) on the membrane. We compared the interaction of HbS and normal HbA with large unilamellar phosphatidylserine (PS) liposomes under low salt/pH conditions. Admixture of oxyHb and dioleoyl-PS resulted in loss of absorbance at 412 nm, the apparent first order rate constant for which was .25 +/- 0.02 hour-1 for HbA and .85 +/- 0.18 hour-1 for HbS. This was ascribable largely to formation of metHb and hemichromes and was accompanied by some actual transfer of heme from hemoglobin to lipid phase. By comparison, admixture of oxyHb with liposomes made from bovine brain PS having unsaturated acyl chains promoted even faster absorbance loss if the starting liposomal material contained detectable peroxidation by-product. In such cases, actual heme destruction developed with accompanying liberation of free iron and promotion of lipidperoxidation. Fluorescence quenching experiments indicate that hemoglobin/lipid interaction is characterized by very rapid initial electrostatic interaction, followed by development of irreversible changes. Similar changes still occur under conditions of physiologic salt/pH, but they develop much more slowly. The 3.4-fold faster oxidation of HbS versus HbA on lipid observed here represents an additional augmentation of the disparity in oxidation rates for hemoglobins in solution (1.7-fold faster for HbS than for HbA) observed previously. The accelerated promotion of Hb denaturation resulting from lipid contact may help explain deposits of hemichrome on sickle red blood cell membranes, particularly because these cells are in double jeopardy by virtue of having both the mutant HbS and abnormal amounts of peroxidized membrane lipid.  相似文献   
58.
Butturini  A; Gale  RP 《Blood》1994,83(2):336-339
Fanconi anemia is an autosomal recessive disease characterized by a high risk of developing bone marrow (BM) failure and acute myelogenous leukemia. We studied growth of hematopoietic progenitor cells in long- term BM culture (LTBMC) in 8 persons with Fanconi anemia and BM failure. Although LTBMC were initiated with very few BM cells, an adherent layer formed in cultures from 7 persons. In these cultures, the number of nonadherent cells increased for 10 to 15 days. Cell growth continued until cultures were terminated at day 35 to 40. During the first 2 weeks of culture, most nonadherent cells were differentiated myeloid cells. By days 35 to 40, the adherent layer contained cells able to initiate secondary LTBMCs. These data indicate that hematopoietic precursors cells able to proliferate and differentiate in vitro are present in the BM of persons with Fanconi anemia and BM failure. They suggest that mechanisms other than absent precursor cells are responsible for BM failure in Fanconi anemia.  相似文献   
59.
One mechanism proposed to play a role in T-cell depletion in human immunodeficiency virus (HIV) infection is apoptosis (activation-induced cell death). We assessed whether apoptosis is related to activation of T cells in vivo and its possible triggers. DNA was extracted from peripheral blood mononuclear cells (PBMC) taken from 16 vertically HIV- infected children and 9 HIV-negative children born to HIV-positive mothers (controls) and tested by agarose gel electrophoresis for the presence of DNA fragments specific for apoptosis. Signs of apoptosis were found on in vitro culture of PBMC from 12 of 16 HIV-infected children, but not in PBMC from the nine controls. Eleven of the 12 HIV- infected children with apoptosis showed an elevated (> 15%) proportion of CD3+/HLA-DR+ cells. This was due to an increased proportion of CD8+/HLA-DR+ cells, as shown in 7 of 7 further tested patients. In none of the probands an increased (> 5%) proportion of IL-2 receptor expressing CD3+ cells was found. T cells undergoing apoptosis were preferentially of the CD8+ phenotype. Expansion of circulating CD8+/interleukin-2 receptor (IL-2R)-/HLA-DR+ T cells is known to occur during active infection with herpes viruses. To investigate the possible role of herpes viral coinfections for apoptosis in HIV infection, we focused on Epstein-Barr virus (EBV) as an example for a herpes virus usually acquired during childhood. In 10 of 12 patients with apoptosis, we found increased levels of EBV genome in PBMC and/or tissues, indicating active EBV replication. By contrast, no increased burden of EBV was found in the four HIV-infected patients without apoptosis or in the controls. Our data indicate that in children the occurrence of apoptosis in HIV infection is closely related to activation of CD8+ T cells. Furthermore, primoinfection with or reactivation of herpes viruses, such as EBV, may substantially contribute to such T-cell activation and the ensuing apoptosis. Additional studies are warranted to evaluate the contribution of herpes virus-triggered apoptosis to the T-cell loss leading to the acquired immunodeficiency syndrome.  相似文献   
60.
Delgado  M; Garrido  E; Martinez  C; Leceta  J; Gomariz  RP 《Blood》1996,87(12):5152-5161
In the present study, the effects of vasoactive intestinal peptide (VIP) and the pituitary adenylate cyclase-activating polypeptides, PACAP27 and PACAP38, in a concentration range from 10(-13) to 10(-6) mol/L were studied in vitro on the spontaneous and dexamethasone (DEX)- induced apoptosis in rat thymocytes. The results show that VIP and both PACAPs inhibit significantly and in a similar way the DNA fragmentation characteristic of glucocorticoid-induced apoptosis and increase the cell survival of thymocytes, with a maximal effect observed at 10(-8) to 10(-9) mol/L. This study showed the ability of the VIP-receptor (VIP- R) antagonist [N-Ac-Tyr1,D-Phe2]-GRF(1-29) amide to partially reverse the inhibitory effect of VIP and both PACAPs on DEX-induced apoptosis, providing evidence for a specific VIP1-R-mediated response and supporting the involvement of a single receptor for the three neuropeptides. Phenotypic analysis showed that VIP, PACAP27, and PACAP38 protect predominantly CD4+CD8+ thymocytes from glucocorticoid- induced apoptosis. These findings suggest that these neuropeptides could be involved in intrathymic T-cell maturation.  相似文献   
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