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91.
We noticed that fetal heart rates (FHR) of immature fetuses intermittently showed unstable sudden and brief falls below baseline FHR that occur over a few or several heartbeats. The frightening falls do not occur in mature fetuses. In nonlinear dynamics, the degree of such abrupt falls in time series is quantified as intermittency. We aimed to investigate the nature and maturational changes of intermittency of the FHR in normal fetuses and to present the intermittency values of normal fetuses according to gestational weeks. FHR data of 450 normal fetuses between 23 and 40 wk of gestation were studied. We performed multifractal analysis and highlighted a very-short-term intermittency (C1alpha, 4 = scale < 16 heartbeats). The C1alpha values exhibited a strong negative linear correlation (r = -0.732, p = 0.0001) with the gestational weeks. At 27-28, 29-30, 33-34, and 37-38 gestational weeks, the C1alpha values were significantly lower than those of the previous 2 or 4 gestational weeks. The maturation of normal fetuses is related to decreasing the severity of the unstable sudden and brief falls in FHR that is measured by C1alpha, the very-short-term intermittency. The C1alpha values according to the gestational weeks that we presented can be used as credible normal milestone values when estimating the degree of maturity of certain FHR. Because the C1alpha captures the degree of the unstable fall in FHR, the C1alpha may also be used in identifying sick fetuses that are associated with hemodynamic instability and sudden bradycardia. 相似文献
92.
Yip YL Novotny J Edwards M Ward RL 《International journal of cancer. Journal international du cancer》2003,104(3):303-309
The extracellular part of ErbB-2 is formed by 4 domains, specifically, L1, L2 that adopt a beta-helical structure and S1, S2 that consist of several cysteine-rich, EGF-fold modules. These ectodomains mediate ErbB-2 dimerisation with itself or with other members of the epidermal growth factor receptor (EGFR) family, events essential to both ErbB-2 signaling and the development of certain malignancies. The anti-ErbB-2 monoclonal antibodies N12, N28 and L87 bind to the polypeptides C531-A586, T216-C235 and C220-C235 respectively. In this study, glycine walking and random mutagenesis were used to further delineate the critical residues involved in antibody binding. A molecular model of ErbB-2 ectodomains was then constructed based on the recently published coordinates of the EGFR (EGFR) model. This model rationalized successfully many features of our epitope mapping, including their location in modules within the S1 and S2 domains and the importance of Arg545, Gln548 and Leu561 for N12 binding. Further investigation of the functional effects of the anti-ErbB-2 monoclonal antibodies demonstrated that N28 strongly stimulated ErbB-2 phosphorylation and MAPK activation whereas N12 had no effect. As bivalency is required for the action of these antibodies we propose that at least 2 different kinds of ErbB-2 homodimers can be formed as relative rotational isomers and that the S1 and S2 domains are instrumental in determining the relative orientations of the ErbB-2 homodimers, such that different signaling effects are induced. 相似文献
93.
Kim HS Kim CS Yum MK 《Clinical and experimental hypertension (New York, N.Y. : 1993)》1999,21(8):1357-1372
To investigate change of cardiac autonomic activity and cardiac complexity during general anesthesia in hypertensive patients, we analyzed electrocardiographic (ECG) data using power spectral analysis and approximate entropy (ApEn). Anesthesia was performed by a mixture of enflurane and nitrous oxide. From 10 minutes before induction of anesthesia(resting state) until 20 minutes after induction, ECG data were obtained from newly diagnosed and untreated hypertensive (n = 18) and normotensive patients (n = 18). Period 1 was defined as the initial 10 minutes after induction and period 2 as the following 10 minutes. The low-, mid-, and high-frequency power and the values of ApEn of the two groups were calculated from ECG recording. At resting state, the powers in all frequency bands and the values of ApEn in hypertensive patients did not differ from those of normotensive patients. During periods 1 and 2, the powers of all frequency range significantly decreased in normotensive group (p<0.05), while they did not change in hypertensive group. The values of ApEn in normotensive patients decreased significantly only during period 2, while those in hypertensive patients decreased during periods 1 and 2 (p<0.05 and p<0.05, respectively). These results suggest that, in the hypertensive patients, persistent autonomic activity under the condition of suppressed cardiac complexity may contribute to the unstable hemodynamic insults from the outset of general anesthesia. 相似文献
94.
Excel97在药物分析中的应用 总被引:1,自引:0,他引:1
目的:在药物分析中,电子表格软件MicrosoftExce197for Windows。方法:利用Excel的数据处理功能,进行药物的图表绘制、数据计算和统计处理,回归分析,特别是计算分析,并可建立分析数据库。结果和结论:Excel操作简单,功能强大,数据分析工作直观。 相似文献
95.
目的:比较国产辛伐他汀与进口辛伐他汀治疗原发性高胆固醇血症的疗效及安全性。方法:采用开放区组随机对照、多中心的临床设计。150例高胆 固醇血症病人分为验证组(50例)、对照组(48例)和开放组(52例),剂量均为每晚顿服10mg,服药8周。结果:验证组与对照组服药前后比较,血清总胆 固醇(TC)分别降低26.36%和28.3%,低密度脂蛋白胆固醇(LDL-C)分别降低33.17%和35.51%;验 相似文献
96.
Diet and cancer prevention: the fiber first diet 总被引:3,自引:0,他引:3
Diet can play a major role in cancer prevention. The international
differences in cancer incidence are largely accounted for by lifestyle
practices that include nutrition, exercise, and alcohol and tobacco use.
About 50% of cancer incidence and 35% of cancer mortality in the U.S.,
represented by cancers of the breast, prostate, pancreas, ovary,
endometrium, and colon, are associated with Western dietary habits. Cancer
of the stomach, currently a major disease in the Far East, relates to
distinct, specific nutritional elements such as excessive salt intake. For
these cancers, information is available on possible initiating genotoxic
factors, promoting elements, and prophylactic agents. In general, the
typical diet in the United States contains low levels of the potent
carcinogenic agents, heterocyclic amines, formed during the cooking of
meats. It provides only about half the potent appropriate fiber intake and
is high in calories. About twice as many calories as would be desirable
come from fat, certain kinds of which enhance the development of cancers.
Other foods with functional properties, such as soy products and tea, can
be beneficial. To achieve reduction in risk of certain cancers, diet must
be optimized, primarily to reduce caloric intake and the fat component. The
latter should be 20% or less of total caloric intake and fiber should be
increased to 25- 35 g per day for adults. One approach to achieving these
goals is the Fiber First Diet, a diet designed around adequate fiber intake
from grains, especially cereals, vegetables, legumes, and fruits, which
thereby reduces both calorie and fat intake. Such dietary improvements will
not only reduce cancer and other chronic disease risks, but will contribute
to a healthy life to an advanced age. A corollary benefit is a lower cost
of medical care.
相似文献
97.
Hye-Young Jeon Seonock Woo Hyokyung Won Bora Kim Seungshic Yum 《Toxicology and Environmental Health Sciences》2010,2(4):231-237
Benzo[k]fluoranthene (B[k]F) is one of numerous polycyclic aromatic hydrocarbons (PAHs) which is a persistent environmental contaminant in air and water. Upon B[k]F exposure, differential gene expression profiling was conducted in marine medaka fish (Oryzias javanicus) using subtractive hybridization. As a result, forty two differentially expressed candidate genes were induced in B[k]F-exposed fish as compared to control group, and the genes were associated with general metabolism, signal transduction, cell cycle, immune response, cytoskeleton, development, nucleotide/protein binding and some were non-categorized. These identified gene candidates have great potential to be developed as biomarkers for the identification of effects of B[k]F exposure in the environment. The results obtained in this study will offer insight to the physiological change induced by B[k]F exposure and will help assess the molecular mechanisms of B[k]F toxicity. 相似文献
98.
In the Orient there is a high frequency of residual intrahepatic stones after biliary tract surgery. Percutaneous removal of residual intrahepatic stones was attempted in a group of 74 patients. Stones were exclusively intrahepatic in 57 patients, whereas 17 patients also had stones in the common bile duct. Biliary strictures were present in 60 cases (81%). A combination of techniques was used, including preshaped angulated catheters, irrigation-suction, balloon dilation of strictures, and crushing of large stones. In 36 cases all stones were removed and in 14 cases most stones were removed, for a success rate of 67.6%. Biliary stricture was the factor most often responsible for failure. 相似文献
99.
Activation and complexation of protein C and cleavage and decrease of protein S in plasma of patients with intravascular coagulation 总被引:2,自引:0,他引:2
Activated protein C (APC) is inhibited by two major plasma inhibitors (PCIs). To find evidence for in vivo complexation of APC, immunoblotting studies were performed on plasmas of 85 patients with suspected disseminated intravascular coagulation (DIC). Samples from 62 of these patients contained 5% to 35% of protein C antigen in APC:inhibitor complexes, indicating that protein C activation and inhibition had occurred. In 24 normal plasmas, no detectable APC:PCI complexes were observed (less than 5%). Patients with higher levels of complexes had more abnormal coagulation test data for DIC. The major band of APC complexes detected by anti-protein C antibodies did not react with antibodies to the heparin-dependent protein C inhibitor (PCI- 1) previously described. Rather, APC was complexed with another recently described plasma protein C inhibitor, PCI-2. Immunoblotting studies for protein S, the cofactor for APC, revealed that the majority of the DIC patient plasmas contained a higher than normal proportion of protein S in cleaved form, suggesting that protein S may have been proteolytically inactivated. Protein S total antigen levels were also found to be low in DIC patients, excluding those with malignancy. These studies support the hypothesis that the protein C pathway is activated during DIC. 相似文献
100.
Lipohemarthrosis of the knee: a review of recent experiences 总被引:4,自引:0,他引:4
The radiographs of 268 patients with knee trauma were retrospectively reviewed. In 15 patients with intraarticular fracture, the images demonstrated fat-fluid levels. In 28 other patients with intraarticular fracture, only joint effusion without a fat-fluid level was depicted. The presence of a fat-fluid level in the knee indicated fracture in all patients in whom it was seen. The absence of such a level, however, did not exclude intraarticular fracture. 相似文献