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21.
Constrained optimization recently has been implemented in the LISREL software package, allowing formulation of parent-offspring transmission models in a simple and efficient manner. A reverse path model of parental transmission is described within the LISREL framework for application to twin and/or adoptive family data. The model incorporates genetic and environmental parameter constraints arising from assortative mating and cultural transmission. An illustration of the LISREL model is given using measures obtained from twins and parents involving fear of social criticism. 相似文献
22.
B. Blad 《Medical & biological engineering & computing》1996,34(5):362-365
In vivo electrical impedance tomography images have been available for some years, and most of them show variation in impedance
amplitude between two different states, for example between inspiration and expiration of the lungs. A refinement of the tomography
technique has made it possible to show images of the complex impedance of the body. If several frequencies are used, more
information on the investigated tissues can be collected, and new areas made available for investigation. It has been shown
that tissues exhibit a characteristic frequency that can be derived from the maximum magnitude of the (negative) reactance.
The characteristic frequency-related images can be calculated from several imaginary part curves obtained using the back-projection
technique. The paper shows in vivo impedance spectra from different parts of the body, determines the characteristic frequency
of the different in vivo measurements and suggests different applications of characteristic frequency imaging. Several data
sets are collected to show the reproducibility of the measurements. 相似文献
23.
目的观察正常孕妇妊娠晚期和妊高征患者血小板参数的变化及临床意义。方法采用日本Sysmex KX-21型血液细胞分析仪分别对正常孕妇(118例)、妊高征患者(59例)及对照组(正常婚检妇女59例)的血液标本进行血小板(PLT)计数、平均血小板体积(MPV)、血小板分布宽度(PDW)的测定。结果妊高征组和正常孕妇组的MPV、PDW显著高于对照组(P〈0.01);妊高征组MPV、PDW明显高于正常孕妇组(P〈0.05);妊高征组的PLT显著低于对照组(P〈0.01)。结论妊高征患者由于血小板消耗和破坏增加,导致血小板减少,MPV、PDW明显增高,因此,检测血小板参数对预测妊高征的发生有一定的参考意义。 相似文献
24.
Summary A total of 19 physical parameters of the head, face, chest, and the fingers were examined in Japanese 50 male and 50 female newborns, measured 8 to 64 hr after birth. Exceptional values were excluded referring to the estimated mean and standard deviations. Normal values are presented as mean ±2 S.D. for each sex. As compared with Caucasian newborns, the Japanese newborns showed longer inner canthal and shorter outer canthal distances, shorter ear lengths, and longer palm and middle finger lengths. 相似文献
25.
为探讨性别、孕周、身长体重指数和日龄对早期新生儿血化学指标的影响,我们对241例早期新生儿六大类常用血化学指标进行了检测和分析,现报道如下。 相似文献
26.
Jochen Fahrenberg Fritz Foerster Hermann-Josef Schneider Wolfgang Müller Michael Myrtek 《Psychophysiology》1986,23(3):323-333
The predictability of individual differences in activation processes was investigated in a multi-method laboratory-field study. Male students of physical education (N=58) were examined under various emotionally activating and physically demanding conditions (mental arithmetic, reaction time, free speech, cold pressor test, bicycle ergometer). The assessment included multi-channel recordings of pre-start phases in an athletic stadium and performance on a 1000 m run. Basal heart rate was also recorded during sleep. This multi-situational assessment was repeated after three weeks, three months, and, for most (N=42) subjects, after one year. Significant relationships exist between scores from corresponding conditions of relaxation, anticipation, and performance of physical exercise. However, with the exception of heart rate, correlation coefficients are rather small and seem to be of questionable predictive validity. A generalizability study further supports the general conclusion: To increase the practical relevance in psychophysiological investigations of stress/strain phenomena, such studies should directly assess individual differences in the criterion situations themselves. 相似文献
27.
Vicari E 《Human reproduction (Oxford, England)》2000,15(12):2536-2544
To evaluate whether bacteriological cure, sperm outcome, spontaneous pregnancy rate and white blood cell (WBC)-related reactive oxygen species (ROS) production were related to the extent of the infection and to an intermittent and repetitive antimicrobial treatment, 122 patients with bacterial [>10(5) colony-forming units (CFU)/ml] male accessory gland infections (MAGI) were studied. According to ultrasound criteria, patients had prostatitis (PR, n = 52), prostatovesiculitis (PV, n = 32) or prostatovesiculoepididymitis (PVE, n = 38). Each group was further subdivided into two subsets: one subset (PR, n = 40; PV, n = 20; PVE, n = 25) was given ofloxacin or doxycycline for 14 consecutive days per month for 3 months; the other subset (PR, n = 12; PV, n = 12; PVE, n = 13) received no treatment. The female partners were also treated. All patients were evaluated before, during (1 and 3 months) and after (3 months) treatment. The bacteriological cure rate was the highest (92.5%) after the third antibiotic course in PR, followed by PV (70.4%), and the lowest in PVE (52.0%). At 3 months after therapy discontinuation, some sperm parameters, seminal WBC concentration and ROS generation (assessed in the 45% Percoll fraction) were ameliorated in PR and PV, whereas no improvement occurred in patients with PVE, except for the percentage of coiled tails. Antibiotic treatment in PR and PV patients led to positive effects on sperm output and spontaneous pregnancy rate (40%) by removing pro-oxidant noxae (microbial and/or WBC-related ROS production). The persistent infertility, dyspermia and sperm-derived ROS overproduction in PVE may relate to a significant percentage of antibiotic-independent re-infection and/or to low antioxidative epididymal properties, which persisted following antimicrobial treatment. 相似文献
28.
Summary A randomized, placebo-controlled, double-blind crossover investigation in 12 patients with non-asthmatic chronic obstructive lung disease and co-existing stable angina pectoris was done to compare two 1-selective adrenoceptor blocking agents, atenolol 100 mg and bisoprolol 20 mg. Systolic and diastolic blood pressures (SBP, DBP), heart rate (HR) as well as airway resistance (AWR, and less frequently forced expiratory volume in 1 s (FEV1) and intrathoracic gas volume (ITGV) were measured in the sitting position before and at various times up to 24 h after drug intake.During the first 4 h both beta-blockers produced a significant reduction in HR in comparison to placebo (p<0.01). Atenolol 100 mg significantly increased AWR relative to placebo and bisoprolol (p<0.05). After 24 h, a significant reduction in HR (p<0.01) could only be demonstrated after bisoprolol, whereas atenolol alone led to a significant elevation in AWR relative to placebo and bisoprolol (p<0.05) at that time.It is concluded that bisoprolol appears to have a high degree of beta1-selectivity, thus providing a wide split between beta1- and beta2-adrenoceptor blockade. Bisoprolol in its therapeutic dose range is expected to be relatively safe as regards bronchoconstriction in patients suffering both from hypertension and/or angina pectoris and chronic obstructive lung disease. 相似文献
29.
Summary The plasma protein binding of amitriptyline, imipramine, clomipramine, and their primary demethylated metabolites were studied by means of a method combining dialysis and gas chromatography. Equilibrium in dialysis of serum containing amitriptyline and its metabolite nortriptyline was attained in about 0.5 h with the drug dissolved in the serum compartment, and in about 2 h with the drug passing from the buffer to the serum compartment.The calculation of free fractions was influenced by variations with dialysis time in the volumes of serum and buffer. Increase of pH in serum increased the protein binding of the weakly basic drugs studied, and made the Donnan distribution effects more pronounced. At pH 7.4, the Donnan effect was negligible.Binding parameters for the 6 tricyclic antidepressant substances studied were estimated for the binding to 1-acid glycoprotein and for total binding in serum. For 1-acid glycoprotein, the k-values ranged from 1·105 to 8·105 M–1, and for pooled serum from 0.4·105 to 8·105 M–1. The determined number of binding sites on the 1-acid glycoprotein was, on average 0.87 for the 6 substances. In serum, the binding capacity was 2–14 times the concentration of 1-acid glycoprotein. 相似文献
30.
Clomiphene, a selective oestrogen receptor modulator, has been utilised in managing male sub-fertility since 1967. Numerous controlled and uncontrolled studies have been published regarding the efficacy of clomiphene citrate in male sub-fertility cohorts. Although the primary intention of treating men with clomiphene citrate is to improve sperm parameters and testosterone levels, some studies have reported paradoxical decline in semen parameters. The information available on decline in sperm parameters following treatment with clomiphene is sparse. We conducted a systemic review using PubMed, Embase, Cochrane Library and Scopus databases for original studies reporting adverse effects of clomiphene citrate therapy on sperm parameters. This systematic review includes 384 men from 11 different studies that reported adverse effects of clomiphene citrate therapy. Of the men included in these studies, 19%, 21%, 17% and 24% of clomiphene-treated men demonstrated a decrease in sperm count, concentration, motility and total motile sperm count respectively. In up to 17% of patients, deterioration of semen parameters did not recover following discontinuation of therapy. In the future, more studies should report on this aspect so the magnitude of this effect can be more clearly understood. 相似文献