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101.
102.
Background  Atypical meningioma accounts for about 4.7% to 7.2% of all kinds of meningiomas, which is invasive with a relatively high recurrence and mortality. The objective of this study was to investigate the clinical manifestations and therapeutic strategies of atypical meningioma.
Methods  A total of 74 patients who underwent surgical treatment and pathologically confirmed for atypical meningioma in Neurosurgery Department of Beijing Tiantan Hospital from January 2003 to December 2008 were enrolled in this study. The characteristics of the tumors as well as therapeutic regimens and follow-up data were reviewed. After surgery, 56 patients underwent radiotherapy. Patients were followed up for about 3.5 years (range, 0.5–6.0 years), and 58 patients completed follow-up.
Results  Of the 58 patients who completed follow-up, good recovery was found in 30, neurological dysfunction in 15, and death in 13. Of the 58 patients, 21 had recurrent meningioma and 18 underwent a second surgery.
Conclusions  Atypical meningioma is difficult to manage, with a high recurrence rate and poor survival. The extent of tumor resection and histological grade are the key determinants of outcome. Radiation therapy can be used as an adjunctive treatment after total or partial resection.
  相似文献   
103.
Xing GG  Liu FY  Qu XX  Han JS  Wan Y 《Experimental neurology》2007,208(2):323-332
Our previous study has reported that electroacupuncture (EA) at low frequency of 2 Hz had greater and more prolonged analgesic effects on mechanical allodynia and thermal hyperalgesia than that EA at high frequency of 100 Hz in rats with neuropathic pain. However, how EA at different frequencies produces distinct analgesic effects on neuropathic pain is unclear. Neuronal plastic changes in spinal cord might contribute to the development and maintenance of neuropathic pain. In the present study, we investigated changes of spinal synaptic plasticity in the development of neuropathic pain and its modulation by EA in rats with neuropathic pain. Field potentials of spinal dorsal horn neurons were recorded extracellularly in sham-operated rats and in rats with spinal nerve ligation (SNL). We found for the first time that the threshold for inducing long-term potentiation (LTP) of C-fiber-evoked potentials in dorsal horn was significantly lower in SNL rats than that in sham-operated rats. The threshold for evoking the C-fiber-evoked field potentials was also significantly lower, and the amplitude of the field potentials was higher in SNL rats as compared with those in the control rats. EA at low frequency of 2 Hz applied on acupoints ST 36 and SP 6, which was effective in treatment of neuropathic pain, induced long-term depression (LTD) of the C-fiber-evoked potentials in SNL rats. This effect could be blocked by N-methyl-d-aspartic acid (NMDA) receptor antagonist MK-801 and by opioid receptor antagonist naloxone. In contrast, EA at high frequency of 100 Hz, which was not effective in treatment of neuropathic pain, induced LTP in SNL rats but LTD in sham-operated rats. Unlike the 2 Hz EA-induced LTD in SNL rats, the 100 Hz EA-induced LTD in sham-operated rats was dependent on the endogenous GABAergic and serotonergic inhibitory system. Results from our present study suggest that (1) hyperexcitability in the spinal nociceptive synaptic transmission may occur after nerve injury, which may contribute to the development of neuropathic pain; (2) EA at low or high frequency has a different effect on modulating spinal synaptic plasticities in rats with neuropathic pain. The different modulation on spinal LTD or LTP by low- or high-frequency EA may be a potential mechanism of different analgesic effects of EA on neuropathic pain. LTD of synaptic strength in the spinal dorsal horn in SNL rats may contribute to the long-lasting analgesic effects of EA at 2 Hz.  相似文献   
104.
Disrupted-in-Schizophrenia-1 (DISC1) has first been identified as a candidate gene for schizophrenia through study of a Scottish family with a balanced (1; 11) (q42.1; q14.3) translocation. Lots of linkage and association studies supported DISC1 as a risk factor for schizophrenia. In this study, we genotyped three SNPs in DISC1 using a set of Han Chinese samples of 560 schizophrenics and 576 controls. No positive association was detected in the whole samples but analysis of allele frequencies in female samples showed weak association between SNP rs2295959 and the disease (chi(2)=6.188, P=0.0135, OR=0.728, 95% CI=0.567-0.935). Our results provide further evidence for sex difference for the effect of the gene on the aetiology of schizophrenia. Our findings also would encourage further studies, particularly family-based association studies with larger samples, to analyze the association between DISC1 and schizophrenia.  相似文献   
105.
Electroacupuncture (EA) has been clinically applied for treating different medical conditions, such as pain, strain, and immune diseases. Low- and high-frequency EAs have distinct therapeutic effects in clinical practice and experimental studies. However, the molecular mechanism of this difference remains obscure. The arcuate nucleus (Arc) is a critical region of the hypothalamus and is responsible for the effect of EA stimulation to remote acupoints. Gene expression profiling provides a powerful tool with which to explore the basis of physiopathological responses to external stimulus. In this study, using cDNA microarray, we investigated gene expressions in the rat Arc region induced by low-frequency (2-Hz) and high-frequency (100-Hz) EAs to two remote acupoints, zusanli (ST36) and sanyinjiao (SP6). We have found that more genes were differentially regulated by 2-Hz EA than 100-Hz EA (154 vs. 66 regulated genes/ESTs) in Arc, especially those related to neurogenesis, which was confirmed by qRT-PCR. These results demonstrate that the expression level of genes in the Arc region could be effectively regulated by low-frequency EA, compared with high-frequency EA, helping to uncover the mechanisms of the therapeutic effects of the low-frequency EA. Our results also indicate different-frequency EAs are spatially specific.  相似文献   
106.
107.
Background:Contrast-enhanced ultrasound is a dynamic and continuous modality providing real-time view of vascularization and flow distribution patterns of different organs and tumors.In order to evalua...  相似文献   
108.
通过免疫沉淀法检测c-fos蛋白,研究辛卡利特和和阿片肽对大鼠脑和脊髓c-fos表达的影响。结果表明,辛卡利特和NDAP可刺激脑和脊髓c-fos的表达(P均<0.01),羟甲芬太尼也有诱导作用(P<0.01)。而辛卡利特和NDAP对脊髓c-fos的表达有协同作用(P<0.01),相反,羟甲芬太尼则拮抗辛卡利特对脑和脊髓c-fos的表达(P<0.05)。结果提示在c-fos水平辛卡利特与不同的阿片肽起不同作用。  相似文献   
109.
Objectives are to investigate the effects of benzo[a]pyrene (B[a]P) on the autonomic nervous system of coke oven workers. One hundred eighty-four coke oven workers were divided into 3 groups according to their working sites (coke oven bottom group, coke oven side group and coke oven top group), and 93 referents were recruited. B[a]P monitored by air sampling pumps as well as urinary 1-hydroxypyrene (1-OH-Py) was determined by high performance liquid chromatograph with a fluorescence detector (HPLC-FD). The autonomic nervous system (ANS) function was determined by 4 tests: Valsalva Manoeuvre heart rate variation (HR-V), variation of heart rate when breathing deeply (HR-DB), variation of heart rate when instantly standing up (HR-IS, including RR30:15 and RRmax:min) and variation of blood pressure when instantly standing up (BP-IS). The B[a]P mean concentrations in coke oven bottom, coke oven side and coke oven top were 19, 185 and 1,623 ng/m(3), respectively. The levels of urinary 1-OH-Py were markedly higher in the 3 exposed groups than that in the referent group (p<0.01). No significant difference was found in each group between smokers and non-smokers (p>0.05). Compared with referents, HR-V decreased significantly in coke oven workers (p<0.01), representing modulation of parasympathetic nervous function. However, no statistical differences were found in HR-DB, RR30:15, RRmax:min and BP-IS between the exposed groups and the control group (p>0.05). HR-V decreased with the increment of 1-OH-Py (p<0.05), and results of multiple linear stepwise regression demonstrated that external exposure level and duration of education entered the HR-V model; age was a significant factor of HR-DB and RRmax:min, but no variable was involved in RR30:15 and BP-IS regression. Benzo[a]pyrene affects the autonomic nervous function of coke oven workers mainly by down-regulating the parasympathetic nervous function.  相似文献   
110.
纳米技术在肿瘤诊断与治疗中的应用   总被引:5,自引:0,他引:5  
Chen RF  Chen JS 《癌症》2004,23(12):1714-1716
利用纳米技术进行恶性肿瘤早期诊断和治疗是目前生物技术领域中最前沿的研究课题,迄今实验室细胞模型研究和临床前动物模型研究已取得了重大进展,纳米生物技术将成为继放疗、化疗和手术治疗后治疗肿瘤的更有效的方法。本文综述了纳米技术在肿瘤诊断和治疗中最新进展。  相似文献   
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