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91.
Demonstration of a second rapidly conducting cortico-diaphragmatic pathway in humans 总被引:5,自引:1,他引:5
Tarek Sharshar Nicholas S. Hopkinson Sophie Jonville Hélène Prigent Robert Carlier Mark J. Dayer Elisabeth B. Swallow Frédéric Lofaso John Moxham Michael I. Polkey 《The Journal of physiology》2004,560(3):897-908
Functional imaging studies in normal humans have shown that the supplementary motor area (SMA) and the primary motor cortex (PMC) are coactivated during various breathing tasks. It is not known whether a direct pathway from the SMA to the diaphragm exists, and if so what properties it has. Using transcranial magnetic stimulation (TMS) a site at the vertex, representing the diaphragm primary motor cortex, has been identified. TMS mapping revealed a second area 3 cm anterior to the vertex overlying the SMA, which had a rapidly conducting pathway to the diaphragm (mean latency 16.7 ± 2.4 ms). In comparison to the vertex, the anterior position was characterized by a higher diaphragm motor threshold, a greater proportional increase in motor-evoked potential (MEP) amplitude with voluntary facilitation and a shorter silent period. Stimulus–response curves did not differ significantly between the vertex and anterior positions. Using paired TMS, we also compared intracortical inhibition/facilitation (ICI/ICF) curves. In comparison to the vertex, the MEP elicited from the anterior position was not inhibited at short interstimulus intervals (1–5 ms) and was more facilitated at long interstimulus intervals (9–20 ms). The patterns of response were identical for the costal and crural diaphragms. We conclude that the two coil positions represent discrete areas that are likely to be the PMC and SMA, with the latter wielding a more excitatory effect on the diaphragm. 相似文献
92.
Nocardia ignorata, a new agent of human nocardiosis isolated from respiratory specimens in Europe and soil samples from Kuwait
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Rodríguez-Nava V Couble A Khan ZU Pérouse de Montclos M Brasme L Villuendas C Molinard C Boiron P Laurent F 《Journal of clinical microbiology》2005,43(12):6167-6170
Nocardia ignorata is a recently described species identified on the basis of a single isolate of unknown origin. Here we describe the epidemiological, phenotypic, and phylogenetic characteristics of this new species, based on five new clinical and soil isolates. 相似文献
93.
P53 overexpression as an indicator of overall survival and response to treatment in osteosarcomas 总被引:5,自引:0,他引:5
Pápai Z Féja CN Hanna EN Sztán M Oláh E Szendrôi M 《Pathology oncology research : POR》1997,3(1):15-19
The p53 gene located at chromosome 17pl3 is found to be altered (allelic loss or other mutation) in multiple human cancers,
including osteosarcomas. The mutated gene produces a protein with a prolonged half-life thus rendering it detectable by conventional
immunohistochemistry. We examined the correlation between p53 expression and clinical prognosis as well as response to therapy.
Twentyone patients with previously untreated and histologically verified highly malignant osteosarcoma were used for this
study. Biopsy material taken both prior to the start of COSS 91 protocol and at the time of surgery (ten weeks later) was
examined for alterations in p53 protein expression and drug resistance. Two patients who had strong (+++) p53 protein expression
and three others who became positive during the chemotherapy had significantly worse prognosis (all of them died within one
year) than those who showed no p53 expression both at biopsy and after chemotherapy (all 11 patients are alive, average follow-up
time: 3.5 years). All patients who showed any kind of positive p53 protein expression on initial biopsy were non-respon-ders
to chemotherapy. In contrast, 69% (9 out of 13) of those who exhibited no p53 expression on initial biopsy were responders
or intermediate responders to chemotherapy. We concluded that p53 expression may be a useful prognostic factor in osteosarcomas.
The direct correlation between p53 positive expression and resistance to therapy can help in identifying patients who are
in need of a more vigorous or different chemotherapeutical protocol. 相似文献
94.
A trace element preparation (Béres Drops Plus, BDP) produced immunomodulatory effects in previous in vitro and in vivo experiments.
Here, C57B1/6 inbred mice were transplanted with either Lewis lung tumor or with B16 melanoma. BDP was given intraperitoneally
a. before transplantation; b. after transplantation or c. after the removal of the primary tumor. As a result, BDP pretreatment
could slow down the tumor progression by decreasing the number and the volume of metastases as well as the proportion of mice
with metastases without influencing the growth of the primary tumors. Furthermore, BDP treatment improved the immunological
activity of the tumor-bearing host, too. These preliminary data suggest that the parenteral administration of the practically
non-toxic BDP could help to control tumor progression in experimental models. 相似文献
95.
96.
B. S. Él'tsefon L. N. Efremova A. R. Rudman E. M. Kopylova V. N. Mel'nikova V. T. Pleshakov Z. P. Belyaeva 《Pharmaceutical Chemistry Journal》1991,25(10):744-749
Translated from Khimiko-Farmatsevticheskii Zhurnal, No. 10, pp. 68–71, September–October, 1991. 相似文献
97.
The Prader-Willi syndrome shortens the life of patients due to the morbid obesity which it entails. The compulsive hyperphagia
associated with it makes a dietetic treatment or a gastroplasty difficult. This study presents the case-histories of three
patients suffering from the Prader-Willi syndrome who were operated on by means of a Scopinaro's bilio-pancreatic diversion.
Following a marked reduction the first year, the weight loss stabilized and then tended to diminish. The observation of three
cases which continued for two and a half to six years did not reveal any considerable metabolic problems. The deficiency of
iron, vitamins D and B12 as well as folic acid had to be made up by supplementation. These results are comparable with the
most favorable ones in the literature. Even if the effect on the weight loss is not spectacular, the operation manages to
hold off the development of the obesity, inexorable for those with the Prader-Willi syndrome, and prevents lethal complications,
without having notable side effects. Lifting coercive dietary measures improves the quality of life. 相似文献
98.
Coleman WP Benzel D Cahill DW Ducker T Geisler F Green B Gropper MR Goffin J Madsen PW Maiman DJ Ondra SL Rosner M Sasso RC Trost GR Zeidman S 《Journal of spinal disorders》2000,13(3):185-199
From the beginning, the reporting of the results of National Acute Spinal Cord Injury Studies (NASCIS) II and III has been incomplete, leaving clinicians in the spinal cord injury (SCI) community to use or avoid using methylprednisolone in acute SCI on the basis of faith rather than a publicly developed scientific consensus. NASCIS II was initially reported by National Institutes of Health announcements, National Institutes of Health facsimiles to emergency room physicians, and the news media. The subsequent report in the New England Journal of Medicine implied that there was a positive result in the primary efficacy analysis for the entire 487 patient sample. However, this analysis was in fact negative, and the positive result was found only in a secondary analysis of the subgroup of patients who received treatment within 8 hours. In addition, that subgroup apparently had only 62 patients taking methylprednisolone and 67 receiving placebo. The NASCIS II and III reports embody specific choices of statistical methods that have strongly shaped the reporting of results but have not been adequately challenged or or even explained. These studies show statistical artifacts that call their results into question. In NASCIS II, the placebo group treated before 8 hours did poorly, not only when compared with the methylprednisolone group treated before 8 hours but even when compared with the placebo group treated after 8 hours. Thus, the positive result may have been caused by a weakness in the control group rather than any strength of methylprednisolone. In NASCIS III, a randomization imbalance occurred that allocated a disproportionate number of patients with no motor deficit (and therefore no chance for recovery) to the lower dose control group. When this imbalance is controlled for, much of the superiority of the higher dose group seems to disappear. The NASCIS group's decision to admit persons with minor SCIs with minimal or no motor deficit not only enables statistical artifacts it complicates the interpretation of results from the population actually sampled. Perhaps one half of the NASCIS III sample may have had at most a minor deficit. Thus, we do not know whether the results of these studies reflect the severely injured population to which they have been applied. The numbers, tables, and figures in the published reports are scant and are inconsistently defined, making it impossible even for professional statisticians to duplicate the analyses, to guess the effect of changes in assumptions, or to supply the missing parts of the picture. Nonetheless, even 9 years after NASCIS II, the primary data have not been made public. The reporting of the NASCIS studies has fallen far short of the guidelines of the ICH/FDA and of the Evidence-based Medicine Group. Despite the lucrative "off label" markets for methylprednisolone in SCI, no Food and Drug Association indication has been obtained. There has been no public process of validation. These shortcomings have denied physicians the chance to use confidently a drug that many were enthusiastic about and has left them in an intolerably ambiguous position in their therapeutic choices, in their legal exposure, and in their ability to perform further research to help their patients. 相似文献
99.
C-Jun NH(2)-terminal kinase mediates proliferation and tumor growth of human prostate carcinoma. 总被引:1,自引:0,他引:1
Yong-Min Yang Frédéric Bost Wilfried Charbono Nicholas Dean Robert McKay Johng S Rhim Chantal Depatie Dan Mercola 《Clinical cancer research》2003,9(1):391-401
PURPOSE: C-Jun NH(2)-terminal kinase (JNK) has been implicated in numerous functions including stress responses, apoptosis,and transformation. The role in transformation is based largely on studies of isolated cell types with little indication of whether JNK plays a general role in a specific human tumor type or whether this occurs in vivo. EXPERIMENTAL DESIGN: We examined 9 human prostate carcinoma cell lines in vitro and a representative line in vivo. RESULTS: For all of the cell lines proliferation is highly correlated with serum-supported JNK activity (r(Pearson) = 0.91; P = 0.004), whereas no relationship was observed for 10 human breast cancer cell lines (r(Pearson) = -0.32). Treatment with characterized antisense oligonucleotides complementary to sequences common to either the JNK1 or JNK2 family of isoforms showed that, whereas antisense JNK1 inhibited growth by a maximum of 57%, antisense JNK2 inhibited proliferation up to 80%. Sense and scrambled control oligonucleotides had little effect (average 3.7 +/- 1.5%). Moreover, systemic treatment of mice bearing established xenografts of PC3 prostate carcinoma cells with antisense JNK1 and JNK2 led to inhibition tumor growth by 57% (P < 0.002) and 80% (P < 0.001), respectively. The difference is significant (P < 0.012). Combined antisense treatment led to a significant increase in frequency of tumor regression (P = 0.022). CONCLUSION: These results indicate that JNK is required for growth of prostate carcinoma cells in vitro and in vivo, and additionally indicate that JNK2 plays a dominant role. The JNK pathway is a novel target in the treatment of prostate carcinoma. 相似文献
100.
Gábor RÉPÁssy Csaba Forster-HorvÁth Attila JuhÁsz Róza ÁDÁny Anna TamÁssy József TÍmÁr 《Pathology oncology research : POR》1998,4(1):14-21
Twelve laryngeal squamous cell carcinoma cases (7 laryngeal and 5 hypopharyngeal cancer; 15 samples) were analysed by immunohistochemistry
for the expression of invasion markers CD44v6/v3, NM23 and matrix metalloproteinase, MMP2. The laryngeal epithelium showed
CD44v6+v3+NM23- /MMP2- phenotype. When tumors were grouped into TNM categories the phenotype of the T2 and T3 tumors was similar, characterised
by decreased CD44v3+ and lack of MMP2 expressions. Meanwhile the NM23 expression was more frequent in T3 tumors. In T4 stage the frequency of
NM23 and MMP2 positive cases increased (5/6 and 4/6, respectively) but there was no correlation with the appearence of lymph
node metastasis. Comparison of the phenotype of laryngeal and hypopharyngeal tumors, irrespective of the TNM stages, revealed
characteristic differences: T2 stage laryngeal tumors showed decreased CD44v3 and occasional NM23 and MMP2 positivity, while
in T3 stage these tumors were characterised by increased frequency of NM23 positivity. The phenotype of the hypopharyngeal
tumors was significantly different with a high frequency of MMP2 positive cases (5/6) and NM23+1ow CD44v3+ phenotype. The sharp differences in the phenotypes of laryngeal and hypopharyngeal carcinomas were connected to the differences
in their invasive capacity unlike to the size of the tumors, since the T4 stage hypopharyngeal tumors had a significantly
smaller size than laryngeal ones, even at lower stages.
This work was supported by the Hungarian Ministry of Welfare: ETT No: T-11-100/93 相似文献