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61.
Phuc Nguyen 《Child & youth care forum》1992,21(2):91-104
A Vietnamese social work and youth studies student describes her experiences and her feelings as a volunteer intern in an urban shelter program for children and youth in the United States. 相似文献
62.
Elevated NMDA receptors in parkinsonian striatum. 总被引:3,自引:0,他引:3
Dopamine-glutamate interactions contribute to normal striatal function and have been implicated in neurotoxicity at nigrostriatal dopamine (DA) terminals. The present study examined the striata of idiopathic Parkinson's disease (PD) patients and age-matched controls for regional differences in the DA transporter and binding to N-methyl-D-aspartate (NMDA) receptors. [3H]Mazindol labeling of the DA transporter was reduced by 70-80% in the caudate and putamen of PD patients, with reductions being more extensive dorsally than ventrally. In contrast, L-[3H]glutamate binding to NDMA-sensitive receptors was 20-40% higher in PD cases than in controls. These findings raise the possibility that modifications occur within corticostriatal glutamate synapses of PD patients, possibly as a consequence of reduced nigrostriatal DA activity. 相似文献
63.
Intra-operative quick insulin assay to confirm complete resection of insulinomas guided by selective arterial calcium injection (SACI) 总被引:1,自引:0,他引:1
Oliver Gimm Evelyn König Phuong Nguyen Thanh Michael Brauckhoff Wolfram Karges Henning Dralle 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):679-684
Background and aims Insulinomas are rare endocrine disorders. Pre-operatively, conventional imaging techniques often fail to localise the tumor.
In addition, due to the lack of quick insulin assays, intra-operative confirmation of complete resection was impossible until
recently.
Materials and methods Six patients with biochemical evidence of an insulinoma underwent pre-operative localisation studies and selective arterial
calcium injection (SACI). In addition, insulin was measured before surgery and every 10–15 min after resection of the tumor
using a quick insulin assay.
Results Pre-operative localisation studies identified the tumor correctly as follows: endosonography: three of four, magnetic resonance
imaging: two of four and SACI: six of six. Tumors in the head and body were enucleated while those in the tail were resected
(n = 2, each). Those three patients, in whom magnetic resonance imaging and/or endosonography could localise the tumors pre-operatively,
underwent laparoscopic surgery while the remaining three patients underwent open surgery. Intra-operatively, insulin dropped
to normal levels within 20 min in all cases. After a follow-up of 0.8–3 years, all patients remained biochemically cured.
Conclusions Pre-operatively, SACI appears to be a very sensitive localisation technique and may be most helpful in guiding the surgeon
if conventional imaging techniques fail to localise the tumor. Complete removal of an insulinoma can be reliably predicted
using a quick insulin assay.
This paper was presented at the 2nd Biennial Meeting of the European Society of Endocrine Surgeons (ESES), May 18–20, 2006,
Krakow, Poland. 相似文献
64.
凋亡抑制蛋白XIAP与肿瘤多药耐药 总被引:1,自引:0,他引:1
XIAP(X-linked inhibitor of apoptosis protein)是凋亡抑制蛋白(inhibitors of apoptosis protein,IAP)家族中最有效的内源性凋亡抑制因子,可以通过直接抑制caspases或者参与信号转导途径抑制细胞凋亡。研究发现,XIAP与肿瘤多药耐药有密切关系,并且有可能成为逆转肿瘤多药耐药提高化疗效果的治疗新靶点。 相似文献
65.
Background
Cancer cells recurrently develop into acquired resistance to the administered drugs. The iatrogenic mechanisms of induced chemotherapy-resistance remain elusive and the degree of drug resistance did not exclusively correlate with reductions of drug accumulation, suggesting that drug resistance may involve additional mechanisms. Our aim is to define the potential targets, that makes drug-sensitive MCF-7 breast cancer cells turn to drug-resistant, for the anti-cancer drug development against drug resistant breast cancer cells. 相似文献66.
Hemorrhagic disseminated intravascular coagulation (DIC) associated with the presence of underlying advanced or metastatic tumors are often difficult to control by conventional methods. We report the use of recombinant activated factor VII (rFVIIa) in patients with cancer and bleeding secondary to DIC. A total of 18 patients with cancer met pre-defined criteria for DIC. All patients had failed to respond to transfusion with blood products and treatment of the underlying malignancy prior to the introduction of rFVIIa. The median laboratory data at the time of treatment with rFVIIa were as follows: hemoglobin, 7.7 g/dl; platelets, 54 x 10(9)/l; prothrombin time, 21 s; activated partial thromboplastin time, 41 s fibrinogen, 83 mg/dl; D-dimer, 17 microg/ml; and antithrombin, 32%. The dose of rFVIIa was 90 microg/kg and the median number of doses administered was 5 (range, 3-10). Serial measurements of coagulation parameters were obtained at frequent intervals during treatment with rFVIIa. Of the 18 patients, 15 responded with cessation of bleeding and improvement in coagulation data. The prothrombin time and activated partial thromboplastin time normalized in all responding patients within 24 h of treatment. The median fibrinogen was 214 mg/dl while the median D-dimer was 6 microg/dl at 48 h following the administration of rFVIIa. No thromboembolic complications were observed following rFVIIa. Our data provide evidence that rFVIIa can be used successfully to control the hemorrhagic episodes associated with DIC. Although this type of treatment appears to be safe, close monitoring of the patients is warranted. 相似文献
67.
Tom C Nguyen Allen Cheng Frederick A Tibayan David Liang George T Daughters Neil B Ingels David Craig Miller 《European journal of cardio-thoracic surgery》2007,31(3):423-429
OBJECTIVE: Septal-lateral annular cinching ('SLAC') corrects both acute and chronic ischemic mitral regurgitation in animal experiments, which has led to the development of therapeutic surgical and interventional strategies incorporating this concept (e.g., Edwards GeoForm ring, Myocor Coapsys, Ample Medical PS3). Changes in left ventricular (LV) transmural cardiac and fiber-sheet strains after SLAC, however, remain unknown. METHODS: Eight normal sheep hearts had two triads of transmural radiopaque bead columns inserted adjacent to (anterobasal) and remote from (midlateral equatorial) the mitral annulus. Under acute, open chest conditions, 4D bead coordinates were obtained using videofluoroscopy before and after SLAC. Transmural systolic strains were calculated from bead displacements relative to local circumferential, longitudinal, and radial cardiac axes. Transmural cardiac strains were transformed into fiber-sheet coordinates (X(f), X(s), X(n)) oriented along the fiber (f), sheet (s), and sheet-normal (n) axes using fiber (alpha) and sheet (beta) angle measurements. Results: SLAC markedly reduced (approximately 60%) septal-lateral annular diameter at both end-diastole (ED) (2.5+/-0.3 to 1.0+/-0.3 cm, p=0.001) and end-systole (ES) (2.4+/-0.4 to 1.0+/-0.3 cm, p=0.001). In the LV wall remote from the mitral annulus, transmural systolic strains did not change. In the anterobasal region adjacent to the mitral annulus, ED wall thickness increased (p=0.01) and systolic wall thickening was less in the epicardial (0.28+/-0.12 vs 0.20+/-0.06, p=0.05) and midwall (0.36+/-0.24 vs 0.19+/-0.11, p=0.04) LV layers. This impaired wall thickening was due to decreased systolic sheet thickening (0.20+/-0.8 to 0.12+/-0.07, p=0.01) and sheet shear (-0.15+/-0.07 to -0.11+/-0.04, p=0.02) in the epicardium and sheet extension (0.21+/-0.11 to 0.10+/-0.04, p=0.03) in the midwall. Transmural systolic and remodeling strains in the lateral midwall (remote from the annulus) were unaffected. CONCLUSIONS: Although SLAC is an alluring concept to correct ischemic mitral regurgitation, these data suggest that extreme SLAC adversely effects systolic wall thickening adjacent to the mitral annulus by inhibiting systolic sheet thickening, sheet shear, and sheet extension. Such alterations in LV strains could result in unanticipated deleterious remodeling and warrant further investigation. 相似文献
68.
汉语成语结尾字事件相关电位N400的研究 总被引:10,自引:2,他引:8
目的 通过记录汉语成语结尾字匹配与不匹配事件相关电位N400的变化,探讨视觉词语认知模式及汉字认知加工特征。方法发采用南方医院研制的事件相关电位仪,对15例21—36岁健康人右利手受试者中,进行汉语成语正常结尾字(匹配字)与歧义字(不匹配字)N400的研究。结果 受试者对结尾词匹配与不匹配组的N400成分在潜伏期及波幅差异有显著性(P≤0.01),不匹配组的N400波幅高,潜伏期长。N400广泛分布于各区,左侧比右侧波幅偏高。结论 汉语成语结尾字匹配与不匹配的N400与字词认知中的语义密切相关,有一定的临床价值,可用于临床多种伴有语言障碍疾病的评估。 相似文献
69.
70.