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11.
The influence of the pre- and postweaning maternal environment on the offspring's phenotype was examined in 5-HT1A and 5-HT1B receptor knockout mice (KO1A and KO1B, respectively). We have previously shown that, when born to and raised by homozygous dams of the same genotype, adult KO1A are more anxious than wild-type (WT) mice, and adult KO1B are hyperactive and slightly less anxious than WT mice. We extend our studies here to the behavioral results of the offspring's own genotype, when the dam's genotype is constant, and the effects of the dam's genotype when the offspring's genotype is constant. In Experiments 1 and 2, KO1A-/- pups produced less ultrasonic vocalizations (USV) than controls in an isolation test on postnatal Day 7 when born to and reared by KO1A dams, either -/- or +/-. Heterozygous F1 pups reared by KO1A-/- dams produced more USV and were less anxious in the plus-maze at 2 to 3 months of age than F1 pups born to and reared by WT dams (Experiment 3). F1 pups reared by KO1B-/- dams produced less USV and were more anxious in the plus-maze than F1 pups reared by WT dams (Experiment 4). The results support a role for maternal effects that may comprise direct effects such as the dam's behavior and nutritional care of the pup, and possibly more complex indirect effects through the establishment of idiosyncratic dam-pup dyadic interactions. We recommend that breeding techniques that rely on same genotype (mutant-mutant or WT-WT) breeding pairs not be used to generate offspring when the focus of research is the study of gene function, but rather when familial effects need to be studied.  相似文献   
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The orders of three endocervical specimens of 3,561 women for Chlamydia trachomatis testing were randomized to determine whether test performance measures of two nucleic acid amplification tests and a DNA probe were affected by swab order. Specimen collection order did not appear to affect the diagnostic accuracy of these tests.  相似文献   
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Susceptibility testing of Eikenella corrodens is usually performed by a Mueller-Hinton sheep blood agar dilution (AD) method. However, this method is impractical for testing only a few strains. We compared AD with the broth microdilution method using Haemophilus test medium (HTM) in order to determine the susceptibility of 36 clinical isolates of E. corrodens to eight antimicrobial agents. MICs obtained by the HTM method yielded 95.5 and 84% agreement (within 2 and 1 log2 dilutions, respectively) with those obtained by AD. The HTM method with incubation in CO2 for 48 h was highly reproducible and constitutes an easy alternative for antimicrobial susceptibility testing of E. corrodens.  相似文献   
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Summary The growth and vascularization patterns of B16 melanoma colonies in the liver and lungs were measured and compared by histological techniques and dye diffusion patterns after injection of the fluorochrome Hoechst 33342. In the liver, the fluorescent pattern of dye diffusion revealed that uninodular tumours measuring up to 146 n in diameter were not functionally vascularized. However, when the nodules fused to give rise to multinodular tumours measuring between 256 and 366 n in diameter, a reticular dye diffusion pattern revealed functional tumour vascularization. In the lungs, subpleural, parenchymal and peritubular (i.e. surrounding blood vessels and airways) tumours were observed. The two former classes were vascularized down to thicknesses and diameters of 49 and 24 m respectively. In contrast, dye diffusion was never seen in peritubular tumour cuffs up to 609 m in thickness. The results indicate differences in vascularization patterns in B16 tumours in the liver and lungs, and differences between tumours growing in different sites within the lungs. If these results are applicable to metastases in these two organs, they indicate potential diffusion-mediated resistance to chemotherapy, and potential hypoxia-mediated resistance to radiotherapy of both metastases and micrometastases.  相似文献   
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OBJECTIVE: To evaluate the effect of prostaglandin E2 (PGE2) and interleukin-1beta (IL-1beta) on integrin expression. DESIGN Cultures of endometrial epithelial cells from normal endometrium. SETTING: All endometrial specimens were obtained from the Obstetrics and gynecology Department of the Catholic University, Rome, Italy. PATIENTS: Four patients were normal menstrual cycles undergoing operative laparoscopy for non-endometrial problems. INTERVENTION: Endometrial samples were collected by uterine courettings. MAIN OUTCOME MEASURE: Immunocytochemistry for beta1 and beta3 integrin subunits. RESULTS: PGE2 clearly enhances both beta1 and beta3 integrin subunit expression. IL-1beta seem to slightly increase only beta3 subunit expression. CONCLUSIONS: In light of the critical role played by eicosanoids in endometrial differentiation, we suggest that PGE2 is also involved in local paracrine regulation of integrin expression.  相似文献   
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During prenatal life, the ductus arteriosus connects the left pulmonary artery and the descending aorta. Morphometric features (length, external diameter, volume) of the ductus arteriosus in 131 human fetuses (65 males, 66 females) were studied by means of anatomical, digital and statistical methods. Regression analysis was used to investigate the growth of the ductus arteriosus during gestation. The values of the length of the ductus arteriosus ranged from 3.95 mm for the 15 week gestational group to 12.20 mm for the 34th week of gestation. The length of the ductus arteriosus related to fetal age (x) increased according to the linear function y = -3.0726 + 0.4381x. The mean values of the diameter of the ductus arteriosus ranged from 1.34 to 3.49mm for the 15 and 34 week gestational groups, respectively. The growth of the ductus arteriosus diameter followed in accordance with the linear function y = 0.2072 + 0.0935x. The mean values of the ductus arteriosus volume ranged from 5.08 mm3 for the 15 week group to 117.30 mm3 of the 34 week gestation group. The volume growth increased according to the function y = 0.0007x3.3782. Positive correlation coefficients between arterial parameters and fetal age were statistically significant (P < or = 0.01) and reached the following values: r1 = 0.98 for Length, r2 = 0.90 for diameter and r3 = 0.94 for volume. Despite the increase in absolute diameter, the relative diameter of the ductus arteriosus (ductus arteriosus-to-aortic bulb diameter ratio) decreased from 0.80 to 0.48.  相似文献   
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Heart rate reactivity to mental stress is substantially blunted early after heart transplantation, suggesting that the loss of neural modulation limits the cardiovascular response to mental stress. We tested whether reactivity to mental stress recovers during the first year after heart transplantation. Hemodynamic and respiratory responses to mental arithmetic challenge were studied in 20 heart transplant recipients 3, 6, and 12 months after surgery. A normal comparison group was studied at equivalent intervals. Heart rate reactivity to mental arithmetic was significantly reduced in the cardiac transplant group compared to the normal subjects. This effect persisted up to 1 year after transplantation. Heart period variability in the heart transplant recipients was minimal in all three-test sessions. The findings suggest that no functional reinnervation or other compensatory adaptation occurs up to 1 year after heart transplantation.  相似文献   
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