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51.
F. Debiais Dr. L. -G. Durand Z. Guo R. Guardo 《Medical & biological engineering & computing》1997,35(5):480-485
The basic parameters of the spectrogram, the Choi-Williams, and the Bessel distributions are adjusted to provide the best
time-frequency representations (TFRs) of the simulated murmur signals of mitral stenosis, mitral regurgitation, aortic stenosis,
aortic regurgitation, and of two musical murmurs. The initial adjustment of the parameters of each TFR technique is performed
by computing and minimising the relative averaged absolute error between the frequency contours at −3dB and −10dB of each
TFR of the simulated murmurs and those of the theoretical distribution of the same signals. The results show that the spectrogram
generally provides very good to excellent performance in representing the TFRs of stenotic and regurgitant murmurs. Improvements
provided by the Choi-Williams and the Bessel distributions are minor but not systematic for the two signal-to-noise ratios
tested (0 and 30 dB) and for the two frequency contours estimated. The Bessel and the Choi-Williams distributions provide
the best performance for the musical murmurs. The study shows that although a single technique cannot be optimal for all six
murmurs, the spectrogram using a Hamming window of 30 ms is an acceptable compromise to detect the six simutated heart murmurs. 相似文献
52.
不能切除肿瘤的恶性梗阻性黄疸的外科姑息治疗方法繁多,本文介绍自1989年以来,采取开腹经不同途径的带支撑导管胆肠内引流的方法治疗30例,减黄确切,尚对7例高位胆管癌在解除胆道梗阻的基础上行术后(192)Ir和(60)Co联合放疗,提高了病人生存质量及延长了生命。 相似文献
53.
采用"对号入座法"管理病案号,先把姓名索引卡、病案封面、病案号索引簿预先印上号码.待病人入院,取出相应一式三份号码,做好各种索引.结果,派出的病案号被取出,乘下空白的是未使用.如果旧病友再次入院;就要在病案的姓名索引中或电脑中查找旧号,这样有效地控制重号、漏号. 相似文献
54.
本文报告了我科1978~1990年间收治的降突性皮纤维肉瘤23例,均经组织学证实.治疗以手术切除为主,术后局部复发率为65.2%.无一例发生转移.切除不彻底是复发的主要原因.作者指出广泛切除是防止复发的主要措施,手术前后的放疗有可能减少复发. 相似文献
55.
复方天棘胶囊对老龄鼠血气影响的研究 总被引:1,自引:0,他引:1
本研究选用昆明种老龄鼠50只,随机分为正常对照组、阳性对照组和复方天棘胶囊高、中、低剂量组;每组10只。观察灌服复方天棘胶囊溶液对实验性老龄鼠血气的影响。结果表明,老龄鼠灌服2.0、1.0和0.5g/kg体重复方天棘胶囊溶液及5.0g/kg体重红参水煎液10天后,复方天棘胶囊各剂量组均有不同程度的升高动脉血氧分压(PaO_2)和血氧饱和度(SaO_2)的作用;且随剂量的递增,PaO_2和SaO_2明显升高,其中高剂量组升高PaO_2和SaO_2的作用最为明显(P<0.01);红本组SaO_2也有明显升高(P<0.01)。提示复方天棘胶囊具有升高PaO_2和SaO_2的作用。 相似文献
56.
自1992年3月至1994年5月,对中原地区4个省20多个县(市)近200个单位33555名20~75岁的已婚妇女,进行妇科疾病发生情况与年龄、职业、文化、月经、孕产等五种因素关系的调查分析。在33555名妇女中,患病者22370人,总患病率为66.67%,查出妇科疾病42种,计76974例次。结果证明:以25~35岁年龄组发病率最高,其中以内生殖器炎症为主;职业以经商者发病率高,特别是性病患者高于其他职业者二倍以上;文化程度以小学、初中者发病率高,尤其宫颈炎更明显;月经情况:随着经前期紧张综合征的加重,更年期综合征发病率增高;孕产次数越多,患病率越高。本次调查未发现宫颈癌,进一步证明我国对妇女保健工作的关心和重视。 相似文献
57.
Antithrombotic effect of beta,beta''-monochloromethylene diadenosine 5'',5"''-P1,P4-tetraphosphate. 下载免费PDF全文
B K Kim P Zamecnik G Taylor M J Guo G M Blackburn 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(22):11056-11058
The feasibility of using beta,beta'-monochloromethylene diadenosine 5',5"'-P1,P4-tetraphosphate (AppCHCl-ppA) as an antithrombotic agent was studied in a rabbit intracarotid cannula thrombosis model previously shown to be sensitive to antiplatelet agents. This analogue, having a P-C-P bridge in place of a P-O-P internucleoside linkage, has been found resistant to phosphodiesterase activity. Rabbits were infused with the dinucleotide at a dose of 50 mg per kg over a 2-hr period, at a controlled rate by pump. A 1-cm length of polyethylene cannula (1 mm i.d.) was tied into the carotid artery. Animals were stable under general anesthesia during the entire period of the experiment. In the control group, 16 of 20 animals formed clots, an incidence of 80%, whereas in the test animals, 6 of the 20 formed clots (30% incidence, P < 0.05). After preincubation of whole blood with 50 microM AppCHClppA at 37 degrees C for up to 3 hr, a consistent suppression of ADP-induced platelet aggregation was observed. The present study suggests that AppCHClppA may be useful as an antithrombotic agent in certain clinical situations, such as hemodialysis, arteriovenous shunts, and introduction of artificial heart valves. It may also possibly prevent extension of recent clots. The toxicity and metabolism of AppCHClppA have, however, yet to be explored. 相似文献
58.
59.
Kallikrein 4 expression is up-regulated in epithelial ovarian carcinoma cells in effusions 总被引:1,自引:0,他引:1
Davidson B Xi Z Klokk TI Tropé CG Dørum A Scheistrøen M Saatcioglu F 《American journal of clinical pathology》2005,123(3):360-368
We immunohistochemically analyzed kallikrein 4 protein (hK4) expression in patients with epithelial ovarian carcinoma (181 malignant effusions and 103 solid carcinoma lesions). Expression of hK4 was also studied in 32 effusions using immunoblotting. Carcinoma cells expressed hK4 in 144 (79.6%) of 181 effusions and 85 (82.5%) of 103 solid tumors. Expression was seen in 51% or more of tumor cells in 70 effusions but often was limited to 5% or fewer cells in solid tumors (P = .009, primary tumors vs effusions; P = .002, metastases vs effusions). Immunoblotting showed hK4 expression in 31 of 32 specimens. Stromal cell hK4 expression, seen in 48 (46.6%) of 103 lesions, was significantly higher in primary tumors than metastases (26/43 vs 22/60, P = .019). hK4 expression in tumor cells was significantly lower in International Federation of Gynecology and Obstetrics stage IV than stage III tumors (P = .004, all lesions; P = .012, primary tumors). hK4 expression in carcinoma cells was associated with longer overall survival (not significant; P = .14, peritoneal effusions). hK4 is expressed widely in ovarian carcinoma; levels in carcinoma cells are highest in effusions, which might be related to loss of stromal contribution and/or altered microenvironment. hK4 expression in carcinoma cells of effusions or solid tumors does not predict survival. 相似文献
60.
Kazuhiko Yasuml Rong-Jun Guo Hiroyuki Hanai Hajime Arai Eizo Kaneko Hiroyuki Konno Selichi Takenoshita Koichi Hagiwara Haruhiko Sugimura 《Pathology international》1998,48(2):134-137
A new mutation in the serine-threonine klnase domain of the transforming growth factor β type II receptor (TGFpRII) was found in a case of diffuse, B cell non-Hodgkin's lymphoma of the stomach. A mfssense mutation (ACA to GCA, Thr to Ala) was detected In exon 5, and a wild type allele was also present. This Is the first naturally occurring mutation in the klnase domain of this gene identified in human primary lymphoma. The replication error at three loci was negative, and the poly A tract of exon 3, which is frequently a target of mismatch repair genes, was intact. Malignant lymphoma of B cell origin in the stomach Is an addition to an expanding catalogue of tumors with TGFβRII alterations, and the biological sequelae of the change in the functional domain and the clinical characteristics of the patient in this study are intriguing. 相似文献