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991.
Abstract. A simple method is described for the removal of HBsAg from plasma to produce a paste that may be fractionated by standard techniques. 相似文献
992.
The obstetric aspects of 54 pregnancies in 20 women with pseudoxanthoma elasticum (PXE) have been reviewed. Forty live births were delivered vaginally, three of them were preterm. Twelve pregnancies miscarried at between 6 and 14 weeks gestation and two were terminated in the 8th week for psychiatric reasons. Fetal losses in two instances were attributed to cervical incompetence. One baby died at 4 days of age from a complex congenital cardiac anomaly. No abnormal maternal genital or gastrointestinal bleeding was recorded. Hypertension complicated seven pregnancies. Abdominal striae developed in all patients, the severity of which correlated with weight gain and the number of pregnancies. All the women had normal gynaecological histories, none had excessive menstrual bleeding or increased episodes of menorrhagia. The eye, blood vessels and other organ systems involved in PXE were unaffected by pregnancy. Apart from the increased risk of first trimester miscarriage and the cosmetic deterioration of the abdominal skin, there are few serious complications in pregnancy in patients with PXE. 相似文献
993.
994.
Harmful micro- and macroscopic effects of the environmental xenoestrogen p-nonylphenol (p-NP) on the male rat reproductive system have been previously reported. In our study, biochemical evidence of epididymal involvement was sought by determining epididymal marker values after exposure at levels below (5, 20 and 50 mg kg-1) and above (100, 250 and 400 mg kg-1) the "no observed adverse effect" level (NOAEL: 50 mg kg-1 day-1). Exposure to p-NL below the NOAEL did not affect biochemical marker values. At levels above the NOAEL, biochemical markers of epididymal function were affected by the exposure of adults, and by maternal exposure (gestational and lactational periods followed by oral exposure until sexual maturity). l-carnitine was unchanged at all levels of exposure. Exposure of adult males to levels above the NOAEL resulted in higher alpha-glucosidase, suggesting increased epididymal secretory activity. This could upset the balance between secretory and reabsorptive function, and could alter the biochemical composition of the epididymal luminal fluid surrounding spermatocytes during the maturation process. Maternal exposure at levels above the NOAEL resulted in higher tartrate-resistant acid phosphatase activity in the caput-corpus epididymidis, which could indicate an oestrogen-mimicking effect. 相似文献
995.
Hernández-Brooks LL Singha AK Watson KL 《Experimental and clinical psychopharmacology》2002,10(2):113-128
Morphine (0.01-10 mg/kg) promoted rapid autonomic learning of discriminative, Pavlovian conditioned heart rate decelerations to tone signals in male and female rabbits, and the higher doses (1-10 mg/kg) promoted decelerative heart rate orienting reflexes to novel tones. Morphine dose dependently reduced heart rate acceleration to signaled shock but had no effect on heart rate acceleration to unsignaled shock. Morphine did not impair retention of cardiac conditioned reflexes, and its U-shaped dose effect, increasing conditioned heart rate discrimination early in training, reappeared in extinction. The authors propose that morphine promotes autonomic learning of preparatory, compensatory reflexes to signaled stressors that reduce their stressful effects. This action may mimic the normal, adaptive function of an endogenous messenger released by the Pavlovian contingency. 相似文献
996.
The process of change, implemented by the School of Nursing at the University of the Orange Free State so that a paradigm shift in approaches to nursing education at undergraduate level could be achieved, is outlined. The necessity to change, the identification of external and internal variables that impact on change, the founding of a support system, the process of overcoming resistance to change, the evaluation of the process of change and options for the future, are discussed. The rationale for the implementation of a problem-based teaching strategy and the phasing in of a community-based approach to teaching as the heart of the process of change are discussed. 相似文献
997.
Amrita Haikerwal Michael D. Barrera Nishank Bhalla Weidong Zhou Niloufar Boghdeh Carol Anderson Farhang Alem Aarthi Narayanan 《Viruses》2022,14(8)
Acutely infectious new world alphaviruses such as Venezuelan Equine Encephalitis Virus (VEEV) pose important challenges to the human population due to a lack of effective therapeutic intervention strategies. Small interfering RNAs that can selectively target the viral genome (vsiRNAs) has been observed to offer survival advantages in several in vitro and in vivo models of acute virus infections, including alphaviruses such as Chikungunya virus and filoviruses such as Ebola virus. In this study, novel vsiRNAs that targeted conserved regions in the nonstructural and structural genes of the VEEV genome were designed and evaluated for antiviral activity in mammalian cells in the context of VEEV infection. The data demonstrate that vsiRNAs were able to effectively decrease the infectious virus titer at earlier time points post infection in the context of the attenuated TC-83 strain and the virulent Trinidad Donkey strain, while the inhibition was overcome at later time points. Depletion of Argonaute 2 protein (Ago2), the catalytic component of the RISC complex, negated the inhibitory effect of the vsiRNAs, underscoring the involvement of the siRNA pathway in the inhibition process. Depletion of the RNAi pathway proteins Dicer, MOV10, TRBP2 and Matrin 3 decreased viral load in infected cells, alluding to an impact of the RNAi pathway in the establishment of a productive infection. Additional studies focused on rational combinations of effective vsiRNAs and delivery strategies to confer better in vivo bioavailability and distribution to key target tissues such as the brain can provide effective solutions to treat encephalitic diseases resulting from alphavirus infections. 相似文献
998.
Cassia Wells Sheree Schwartz Nancy Phaswana-Mafuya Andrew Lambert Zamakayise Kose Mfezi Mcingana Harry Hausler Amrita Rao Clarence Yah Sosthenes Ketende Stefan Baral 《AIDS and behavior》2018,22(12):3924-3932
Female sex workers (FSW) in South Africa are disproportionately affected by HIV, yet little is known about their HIV-status disclosure with clients. Among 410 FSW participating in a cross-sectional study, 213 were HIV positive and aware of their status prior to enrollment. Among FSW aware of their HIV-status, 35% (74/213) reported disclosing their HIV-status to paying clients, whereas 75% (118/158) of those with regular, non-paying partners disclosed to them. In a multivariable analysis, disclosure to clients was associated with more years of education, disclosure to non-paying partners, and meeting clients at established sex work venues, whereas a history of sexual violence was associated with less disclosure. There was also evidence of mutual disclosure with clients, however disclosure was not associated with condom use with clients or being on antiretrovirals. Safer working environments may improve FSW HIV disclosure practices, however disclosure must also be linked with protective behaviors in this population. 相似文献
999.
Satish Nagula Kamron Pourmand Harry Aslanian Juan Carlos Bucobo Tamas A. Gonda Susana Gonzalez Adam Goodman Seth A. Gross Sammy Ho Christopher J. DiMaio Michelle K. Kim Shireen Pais John M. Poneros David H. Robbins Felice Schnoll-Sussman Amrita Sethi Jonathan M. Buscaglia 《Clinical gastroenterology and hepatology》2018,16(8):1307-1313.e1