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21.
本文应用核磁共振法(NMR)测定了几种混合体系的 HLB 值与混合体系中各组分的 HLB 值。实验结果表明,混合体系中各组分在核磁共振图谱中的积分曲线高度也具有加和性。混合体系的 HLB 值是体系中各组分 HLB 值的加权平均值。因此,对混合体系的 HLB 值可以应用 NMR 法直接测定,也可应用 NMR 法测定各组分的 HLB值,通过计算求得,计算值与实测值完全一致。  相似文献   
22.
本文报告39例临床上除外右房肥大的P波高电压,此种P波高电压主要见于冠心病及急性颅脑疾患,二者之和占76.9%。其形态64%与肺性P波相同。产生的机制可能与结间束传导阻滞、中枢调节机能受累、交感神经兴奋性增高等有关。  相似文献   
23.
We focus on the Fisher information matrix used for design evaluation and optimization in nonlinear mixed effects multiple response models. We evaluate the appropriateness of its expression computed by linearization as proposed for a single response model. Using a pharmacokinetic–pharmacodynamic (PKPD) example, we first compare the computation of the Fisher information matrix with approximation to one derived from the observed matrix on a large simulation using the stochastic approximation expectation–maximization algorithm (SAEM). The expression of the Fisher information matrix for multiple responses is also evaluated by comparison with the empirical information obtained through a replicated simulation study using the first‐order linearization estimation methods implemented in the NONMEM software (first‐order (FO), first‐order conditional estimate (FOCE)) and the SAEM algorithm in the MONOLIX software. The predicted errors given by the approximated information matrix are close to those given by the information matrix obtained without linearization using SAEM and to the empirical ones obtained with FOCE and SAEM. The simulation study also illustrates the accuracy of both FOCE and SAEM estimation algorithms when jointly modelling multiple responses and the major limitations of the FO method. This study highlights the appropriateness of the approximated Fisher information matrix for multiple responses, which is implemented in PFIM 3.0, an extension of the R function PFIM dedicated to design evaluation and optimization. It also emphasizes the use of this computing tool for designing population multiple response studies, as for instance in PKPD studies or in PK studies including the modelling of the PK of a drug and its active metabolite. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
24.
Medial epicondylitis is a chronic noninflammatory condition resulting from mechanical injury. Despite many treatment options, including rest, medications, physiotherapy and operative interventions, the results are too often poor; thus new treatment options are sought. We treated 4 men with chronic epicondylitis (5 affected joints) with extracorporeal shock wave therapy after failed attempts of other treatments. The patients’ complaints were graded with the Nirschl scoring system prior to and six months after therapy. The treatment consisted of three sessions, at 20-day intervals, of 3000 pulses of ultrasonic shock waves from a Piezolith 3000 unit (energy dosage was gradually increased to reach step 10 equaling 0.9 mJ/mm2). At the 6-month follow-up, no patient was pain free. Three cases had slightly lower Nirschl scores than prior to the procedure but the patients rated this difference as insignificant; two cases were unchanged. No complications were observed but all patients rated the procedure as very unpleasant. The well recognized biologic effects of ultrasonographic waves (heat generation, oscillations, cavitation, etc.) that result in functional and structural changes of cellular membranes with sonochemical reactions (acceleration of normal metabolism, oxygenation and reduction in water solutions, polymer degradation, etc.), even if present in our cases, did not result in a noticeable decrease of symptoms, even though we used high energy and more impulses per session. Significant variations in methodology make inconclusive the results of numerous reports on the use of extracorporeal shock waves in epicondylar degenerative problems, although ineffectiveness of such therapy is the conclusion of a review by Haake and colleagues.  相似文献   
25.
腮腺混合瘤(mixed tumor)是颌面部常见的良性肿瘤之一,但本例为高龄患者,且肿瘤重达4 600 g,国内外少见报道[1,2],现报告如下。患者女性,86岁,农民(住院号69133)。主因“左颌面部渐进性增大肿块40余年,”于1999年8月20日上午8时入院。入院体检,一般情况可,心、肺、腹部未见异常  相似文献   
26.
A case of an odontogenic tumor which invaded the intracranial space from the mandible is reported. Judging from the radiographic images it was similar to a malignant tumor. The patient died 17 years after the first visit. According to the final pathological diagnosis, it was malignant odontogenic mixed tumor of low grade which did not belong to any of the WHO classification.  相似文献   
27.
目的:比较二维超声心动图(2DE)和心电图(ECG)对心肌梗塞(MI)定位诊断的异同、优劣。方法:对59例 MI 患者进行了2DE 和 ECG 检查。在2DE 上将左室分为16个节段而分别确定与 ECG 各导联的对应关系,分别计数2DE 上室壁运动异常(WMA)节段数和 ECG 上有异常 Q 波导联所对应节段数,对比分析两种方法检查结果的一致性。结果:2DE 和 ECG 分别检出338和311个节段阳性,两种方法阳性一致率57.9%,两种方法阳性一致率在各壁的高低依次为下壁、前壁、后壁、前间隔、侧壁;两种方法检测结果的差别有显著性(P<0.05);两种方法检测结果的相关系数 r=0.595(P=0.0000)。结论:两种方法的检查结果有较好的一致性,2DE 优于 ECG。  相似文献   
28.
Abstract  Although respiration in trained canines is well investigated, the process of preparing dogs has not been described in any great detail. Moreover, their daytime patterns of sleep and wakefulness during 1 or 2 h of electroencephalogram (EEG) and electrocardiogram (ECG) recordings are not clear. Therefore, we describe the process of selecting and training dogs, in which we recorded EEG and ECG in the laboratory. First, 14 of 1242 dogs dealt with over a 1 year period were chosen. They were trained for 2 h to lie quietly and to sleep in the laboratory; this training procedure was repeated 152 times. Three dogs were then selected and a permanent tracheostomy was performed in one. Finally, EEG and ECG were recorded with the bipolar fine needle electrodes; respiration was recorded simultaneously through a tube inserted to a tracheostomy in one dog. Wakefulness, slow wave sleep (SWS) and rapid eye movement (REM) sleep (REMS) were identified according to the EEG pattern and on the basis of the behavioral criteria. Recordings were performed 12 or 13 times in each dog. Complete sleep cycles, including wakefulness, SWS and REMS in this sequence, were observed 3.9–4.1 times. The mean duration of SWS was 2.2–4.4 min and that of REMS was 3.5–4.6 min. The REMS latency was 33.9–41.8 min. Fluctuation of heart rate with respiration, termed respiratory sinus arrhythmia, was noted in the ECG. Heart beat increased with inspiration and decreased with expiration. The present study demonstrates how to select and train sleeping dogs and shows their undisturbed daytime sleep and wakefulness patterns.  相似文献   
29.
 Rhabdomyosarcoma (RMS) is occasionally found in the female genital tract, and mostly appears as one of the heterologous mesenchymal components in uterine carcinosarcoma designated as malignant mixed müllerian tumour (MMMT). We examined the biological properties of a pure rhabdomyosarcoma (RMS) cell line designated FU-MMT-3, which was newly established from a surgical specimen taken from a patient with uterine MMMT. We also evaluated c-myc and MYCN gene amplification in three RMS cell lines (including FU-MMT-3) derived from three MMMTs by Southern blot analysis. FU-MMT-3 cells were propagated continuously for 57 serial passages over a 2-year period in vitro. FU-MMT-3 was able to produce tumours demonstrating pure RMS in athymic nude mice. Cytogenetically, FU-MMT-3 showed a triploidy pattern, with complex karyotypic abnormalities including trisomy of chromosome 8. All three RMS cell lines, including FU-MMT-3, showed amplification of the c-myc gene (approximately fourfold to eightfold), while no cell lines demonstrated MYCN gene amplification. FU-MMT-3 is considered to provide a useful system for the study of the biological behaviour of RMS in MMMTs. Extra copies of chromosome 8 and c-myc gene amplification may be associated with the rhabdomyoblastic differentiation in MMMT. Received: 7 January 1997 / Accepted: 2 May 1997  相似文献   
30.
We report a patient with graft versus host disease (GVHD) with mixed chimerism (MC). The patient had chronic myelogenous leukemia and received bone marrow transplantation (BMT) from his elder sister. Eighty days after BMT, erythematous lesions appeared on his chest. Histological examination from the skin lesion revealed lymphocytic infiltration into the upper dermis. Eosinophilic necrotic keratinocytes were scattered through the epidermis. Liquefaction degeneration was also recognized. Sicca syndrome appeared from 110 days after BMT. Detection of host origin Y-chromosome-specific DNA by polymerase chain reaction (PCR) method in bone marrow and peripheral blood showed that all bone marrow samples obtained 6 months from BMT were positive for Y-specific DNA, while peripheral blood became positive in the 60th month after BMT. The host origin normal karyotype (46,XY) in the bone marrow samples was identified for the first time in the 60th month after BMT. These results indicate that host-origin hematopoietic cells survived after BMT.  相似文献   
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