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31.
High-frequency deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves the motor symptoms of Parkinson's disease (PD). Opposite changes in mood, such as mania or depression, have been reported after surgery, but it is not known whether these side effects are specifically related to STN DBS. To learn whether STN DBS also influences the limbic loop, we investigated acute subjective psychotropic effects related to levodopa or bilateral STN DBS. After a median postoperative follow-up of 12 months, 50 PD patients completed the Addiction Research Center Inventory (ARCI), assessing subjective psychotropic effects in four conditions: off-drug/on-stimulation; off-drug/off-stimulation; on-drug/off-stimulation; and on-drug/on-stimulation. Both levodopa and STN DBS improved all the ARCI subscales, indicating subjective feelings of well being, euphoria, increase in motivation, and decrease in fatigue, anxiety, and tension. A suprathreshold dose of levodopa was significantly more effective than STN DBS, using the same electrical parameters as for chronic stimulation, on four of the five ARCI subscales. We concluded that 1) both STN DBS and levodopa have synergistic acute beneficial psychotropic effects in PD, 2) the psychotropic effects of both treatments need to be considered in the long-term management of chronic STN DBS, and 3) the results indicate an involvement of the limbic STN in mood disorders of PD.  相似文献   
32.
A modified exeimer laser energy delivery system was used to irradiate 100 segments of normal and fibrous aorta in vitro. The laser beam was scanned into 8 fiber bundles consisting of 50 fibers each resulting in a reduction of the applied pulse energy. The total repetition rate was increased to 150 Hz in order to keep the repetition rate per fiber bundle close to 20 Hz and to minimize thermal injury. The results demonstrate that effective ablation (etch rate per 8 pulses > 2.0 μm) occurred at an energy fluency of 50 mJ/mm2 in both normal and fibrous aorta. Tissue damage (carbonization, tissue separation, fissures, cracks, and vacuolization) was in a range of 100 ± 28 to 152 ± 30 μm for normal aorta and in a range of 57 ± 35 to 110 ± 39 μm for fibrous aorta. We conclude that effective ablation of normal and fibrous human aorta can be achieved by the application of smooth excimer laser coronary angioplasty. This improvement of excimer laser technology may result in a reduction of shock wave- and cavitation-induced damage leading to a reduction of tissue injury. However, this awaits further in vitro and in vivo confirmation. © 1993 Wiley-Liss, Inc.  相似文献   
33.
Radiologic and pathologic mani;estations of 30 peripheral pulmonary masses around l.5-3 cm in dia- meter were compared to the pathologic basis of va- cuole sign and small node sign on tomogram. Stati stics of 100 conventional X-ray tomograms of peri- pheral pulmonary masses about l-3 cm in diameter suggested that the vacuole sign and small node sign, more common in early peripheral lung cancer than in tuberculoma, are valuable for differentiating early peripheral lung cancer from tuberculoma.  相似文献   
34.
We describe the first case of orofacial abnormal movements induced by adrafinil, a vigilance promoting agent of the same pharmacological class as modafinil. The dyskinesias did not spontaneously recover despite adrafinil withdrawal for a 4-month period. They were secondly dramatically improved by tetrabenazine, a presynaptic dopaminergic depleting drug which was introduced after the 4-month adrafinil-free period.  相似文献   
35.
目的进一步认识婴幼儿患者实施外科手术的危险性及规范手术配合程序的重要性,提高配合质量,提出手术配合要点。方法回顾近几年168例婴幼儿患者外科手术护理配合,同时结合自己的临床实际经验和手术配合中的体会,提炼出婴幼儿患者手术的护理配合要点。结果婴幼儿患者手术的配合要做好术前评估,掌握患者心肺主要脏器的功能情况,做好充分准备,手术室感染控制,术中的各项检测,监测输液量、速度及体温维持情况。结论掌握婴幼儿患者手术的护理配合要点,可提高手术配合质量和手术成功率。  相似文献   
36.
CT guided percutaneous fine needle aspiration cytodiagnosis of liver masses   总被引:1,自引:0,他引:1  
  相似文献   
37.
Osteoblasts exhibit enhanced differentiation and altered gene profiles when cultured on hydroxyapatite (HA) compared to plastic surfaces. To begin determining mechanisms for this response, we used proteomics to identify proteins predominantly found in osteoblasts on HA but not plastic surfaces. Two-dimensional gel electrophoresis and Western analyses indicate that fetuin is abundant in extracts from HA, but not plastic surfaces. Incubation of HA and plastic surfaces with cell culture medium (containing 10% serum) under cell-free conditions shows that fetuin is predominantly derived from the culture medium serum and readily adsorbs to the HA surface. However, we did detect low levels of fetuin B mRNA in osteoblasts. Serum albumin, actin-beta, apolipoprotein-AI, and vimentin also adsorbed to HA. To determine the role of fetuin in the HA-induced osteoblast phenotype changes, osteoblasts were seeded onto fetuin-coated or uncoated HA under serum-free conditions. Osteoblast morphology was similar on both HA surfaces, suggesting that HA alone (without adsorbed serum proteins) is sufficient for cell attachment and spreading. Similarly, genes previously reported to be modulated by HA (glvr-1, DMP-1, osteoglycin, and proliferin 3) were modulated even in the absence of fetuin or other serum proteins. These data show that HA surface can be enriched selectively with fetuin from serum; however, neither fetuin or other serum proteins are required to mediate HA-induced osteoblast attachment, spreading, or changes in expression of genes examined. This finding suggests that factors intrinsic to HA are required for the response.  相似文献   
38.
合成了一系列分子量较低的聚乙二醇.聚己内酯-聚乙二醇(Poly(ethylene glycol)-Polycaprolactone-Poly(ethylene glycol),PEG-PCL—PEG)三嵌段共聚物。分别采用FTIR和1H—NMR对其结构进行了表征。所合成的PEG-PCL-PEG共聚物具有良好的水溶性,当水溶液浓度高于临界凝胶浓度(Critical gel concentration,CGC)时,随着温度的变化聚合物水溶液会呈现特有的凝胶-溶胶转变。研究了共聚物亲水疏水链段的比例和长度,以及热历史等对凝胶-溶胶转变行为的影响。通过调节上述条件,可以在一定程度上拓宽凝胶-溶胶转变温度范围,有助于PEG—PCL-PEG水凝胶在可注射药物控制释放系统等方面的应用。  相似文献   
39.
Effect of aging on neuroglobin expression in rodent brain   总被引:5,自引:0,他引:5  
Neuroglobin (Ngb), a recently discovered O2-binding heme protein related to hemoglobin and myoglobin, protects neurons from hypoxic-ischemic injury in vitro and in vivo. In immunostained mouse brain sections, we found widespread expression of Ngb protein in neurons, but not astrocytes, of several brain regions that are prominently involved in age-related neurodegenerative disorders. Western blots from young adult (3 month), middle-aged (12 month), and aged (24 month) rats showed an age-related decline in Ngb expression in cerebral neocortex, hippocampus, caudate-putamen, and cerebellum. Loss of this neuroprotective protein may have a role in increasing susceptibility to age-related neurological disorders.  相似文献   
40.
 Using the whole-cell patch clamp technique, the role of actin microfilament in hyposmotic increase of voltage-operated calcium channel current (I Ba) was studied in guinea-pig gastric myocytes. Hyposmotic superfusate (212 mOsm) increased peak I Ba amplitude by 32.7 ± 6.5%; when cytochalasin-D (Cyt-D, 20 μM), an actin cytoskeleton disruptor, was used, an increase of only 9.7 ± 3.1% was seen. I Baresponse to osmotic stress was potentiated (45.1 ± 4.1% increase) by 20 μM phalloidin, an actin microfilament stabilizer. However, colchicine (100 μM), an microtubule cytoskeleton disruptor, had no effect on either I Ba or its response to hyposmotic solution. Phalloidin also induced a rightward shift of the I/V relationship of I Ba, while Cyt-D itself had no effect. These results suggest that actin cytoskeleton may mediate hyposmotic stretch-induced I Ba increase in gastric smooth muscle. Received: 26 March 1997 / Received after revision: 28 May 1997 / Accepted: 3 June 1997  相似文献   
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