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11.
Effective prevention of recurrent urinary tract infections (UTIs) and possible acute pyelonephritis is of major importance during pregnancy. During 39 pregnancies, 33 women with a history of recurrent UTIs (and, in some instances, pyelonephritis) received postcoital prophylaxis consisting of a single oral dose of either cephalexin (250 mg) or nitrofurantoin macrocrystals (50 mg). While 130 UTIs occurred during a mean observation period of 7 months before prophylaxis, only a single UTI occurred during pregnancy after prophylaxis; this difference was highly significant. Thus the use of one of these effective regimens is strongly recommended for any pregnant woman with a history of recurrent UTIs. The treatment's effectiveness can be explained by two features of the two antibacterial agents involved: both reach high bactericidal concentrations in the urinary tract and induce no (or minimal) resistance in the introital gram-negative bacterial flora. 相似文献
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The voltage-sensitive dye diO-C2-5 was used to produce an in vivo map of the membrane potential in two types of seizures. Mild limbic seizures were induced in rats with kainic acid; clonic convulsive seizures were induced with bicuculline. Kainic acid animals showed various levels of neural depolarization during their seizures in limbic, thalamic, cortical, and brainstem sites. The bicuculline animals showed uniformly greater levels of neural depolarization during their seizures. The magnitude of these changes relative to controls varied across seizure models and reflected the different underlying neural mechanisms for each model. The ability of the technique to capture local electrical events provides a new tool in which to explore brain activity. 相似文献
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D M Desiderio G H Fridland J T Francisco H Sacks J T Robertson R C Cezayirli J Killmar C Lahren 《Clinical chemistry》1988,34(6):1104-1107
The comprehensive metabolic profile of endogenous opioid peptides is established here for human pituitary for the first time. Sixteen human pituitaries, obtained postmortem, were analyzed individually by gradient reversed-phase high-performance liquid chromatography together with a radio-receptor assay with [3H]etorphine as ligand. This combination was used to detect opioid receptor activity. The 16 assay profiles were sufficiently consistent for a composite of them to serve as a comparative basis for other studies on the pathophysiology of the human pituitary. To demonstrate one selected comparison, we present data on a distinctively different profile of opioid receptor activity in the pituitary of one patient who died from a drug overdose. 相似文献
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Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
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Michael S. Sacks David B. Smith Erik D. Hiester 《Annals of biomedical engineering》1997,25(4):678-689
The planar fibrous connective tissues of the body are composed of a dense extracellular network of collagen and elastin fibers
embedded in a ground matrix, and thus can be thought of as biocomposites. Thus, the quantification of fiber architecture is
an important step in developing an understanding of the mechanics of planar tissues in health and disease. We have used small
angle light scattering (SALS) to map the gross fiber orientation of several soft membrane connective tissues. However, the
device and analysis methods used in these studies required extensive manual intervention and were unsuitable for largescale
fiber architectural mapping studies. We have developed an improved SALS device that allows for rapid data acquisition, automated
high spatial resolution specimen positioning, and new analysis methods suitable for large-scale mapping studies. Extensive
validation experiments revealed that the SALS device can accurately measure fiber orientation for up to a tissue thickness
of at least 500 μm to an angular resolution of∼1o and a spatial resolution of±254 μm. To demonstrate the new device’s capabilities, structural measurements from porcine aortic
valve leaflets are presented. Results indicate that the new SALS device provides an accurate method for rapid quantification
of the gross fiber structure of planar connective tissues. 相似文献