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71.
The immunoglobulin nature of Russell bodies 总被引:2,自引:0,他引:2
J B Matthews 《British journal of experimental pathology》1983,64(3):331-335
Although Russell bodies have been widely regarded as aggregates of immunoglobulin (Ig) their true nature remains controversial. This report reinvestigates the Ig reactivity of Russell bodies using an immunoperoxidase technique to detect IgG, IgA, IgM, kappa and lambda light chains and J chain on formalin fixed paraffin embedded tissue. Both intracellular and extracellular Russell bodies stained for Ig heavy and light chain determinants. Generally staining was most intense at the surface of these structures although many appeared to have detectable Ig determinants within the Russell body cores. The results suggest that Russell bodies, irrespective of size or site, are associated with intact Ig molecules. 相似文献
72.
The histology of gonadotropin-secreting bronchogenic carcinoma 总被引:1,自引:0,他引:1
J C Cottrell K L Becker M J Matthews C Moore 《American journal of clinical pathology》1969,52(6):720-725
73.
Preliminary observations on polar body extrusion and pronuclear formation in human oocytes using time-lapse video cinematography 总被引:10,自引:17,他引:10
Payne D; Flaherty SP; Barry MF; Matthews CD 《Human reproduction (Oxford, England)》1997,12(3):532-541
In this study, we have used time-lapse video cinematography to study
fertilization in 50 human oocytes that had undergone intracytoplasmic sperm
injection (ICSI). Time-lapse recording commenced shortly after ICSI and
proceeded for 17-20 h. Oocytes were cultured in an environmental chamber
which was maintained under standard culture conditions. Overall, 38 oocytes
(76%) were fertilized normally, and the fertilization rate and embryo
quality were not significantly different from 487 sibling oocytes cultured
in a conventional incubator. Normal fertilization followed a defined course
of events, although the timing of these events varied markedly between
oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular
waves of granulation within the ooplasm which had a periodicity of 20-53
min. The sperm head decondensed during this granulation phase. The second
polar body was then extruded, and this was followed by the central
formation of the male pronucleus. The female pronucleus formed in the
cytoplasm adjacent to the second polar body at the same time as, or
slightly after, the male pronucleus, and was subsequently drawn towards the
male pronucleus until the two abutted. Both pronuclei then increased in
size, the nucleoli moved around within the pronuclei and some nucleoli
coalesced. During pronuclear growth, the organelles contracted from the
cortex towards the centre of the oocyte, leaving a clear cortical zone. The
oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during
the course of the observation period. The female pronucleus was
significantly smaller in diameter than the male pronucleus (24.1 and 22.4
microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0
respectively, P < 0.0001). After time-lapse recording, oocytes were
cultured for 48 h prior to embryo transfer or cryopreservation. Embryo
quality was related to fertilization events and periodicity of the
cytoplasmic wave, and it was found that good quality embryos arose from
oocytes that had more uniform timing from injection to pronuclear abuttal
and tended to have a longer cytoplasmic wave. In conclusion, we have shown
that time-lapse video cinematography is an excellent tool for studying
fertilization and early embryo development, and have demonstrated that
human fertilization comprises numerous complex dynamic events.
相似文献
74.
75.
Nuclei of the medial septum/diagonal band region of the mammalian forebrain contain neurons that give rise to the septohippocampal pathway, which has separate cholinergic and GABAergic components. This pathway is known to influence hippocampal-dependent memory and learning processes, but the precise role of each component is unclear. In this study, we tested the hypothesis that fast-firing, non-bursting medial septum/diagonal band neurons are GABAergic. We used brain slice preparations from young adult guinea-pigs and rats, or from weanling rats, to perform current-clamp recordings from medial septum/diagonal band neurons. Recorded neurons were injected with biocytin for subsequent visualization with fluorescent avidin, and then hybridized with a 35S-labeled riboprobe for glutamate decarboxylase-67 messenger RNA. As a positive control, guinea-pig cerebellar Purkinje cells were labeled and hybridized with the riboprobe. As expected, labeled Purkinje cells were glutamate decarboxylase-67 messenger RNA positive. Slow-firing, cholinergic (choline acetyltransferase-positive) guinea-pig medial septum/diagonal band neurons were glutamate decarboxylase-67 messenger RNA negative. Contrary to our hypothesis, of the guinea-pig neurons, only three of 11 fast-firing neurons were glutamate decarboxylase-67 positive. Of the rat medial septum/diagonal band neurons, three of four were positive for glutamate decarboxylase-67 messenger RNA.These data suggest that fast-firing, non-bursting neurons of the medial septum/diagonal band, as sampled by sharp-electrode intracellular recordings in brain slices, may be a heterogeneous group of neurons, some of which are GABAergic. Together with recent data demonstrating the presence of another GABAergic marker, parvalbumin, in fast-firing septal neurons, we conclude that GABAergic septohippocampal neurons include a population of fast-firing, non-bursting neurons. The influence of these neurons on the hippocampus is likely to occur on a shorter time-scale and over a wider range of firing frequencies as compared to slowly firing cholinergic septohippocampal neurons. 相似文献
76.
Purified preparations of TYMV contain a number of minor nucleoprotein components distinguishable on the basis of their density in CsCl gradients (R. E. F. Matthews, Virology12, 521–539, 1960). When analysed by polyacrylamide-gel eletrophoresis, the RNA from each of these various components was found to consist of a characteristic set of molecular-weight species. Full-size RNA (2 × 106 daltons) was present only in nucleoproteins B1 and B2. Nucleoproteins B0, B00, and B000 contained RNAs ranging in size from approx 1.3 to 0.28 × 106 daltons. The 0.28 × 106-dalton RNA species was detectable in all nucleoprotein fractions, but was a significant proportion of the RNAs of B000 and B00. Translation of the RNA from each of the nucleoproteins in the wheat germ cell-free protein synthesizing system yielded essentially similar patterns of polypeptides which ranged in size from 5000 to 70,000 daltons. The major radioactive product migrated on SDS-polyacrylamide gels to the same position as TYMV coat protein. The data suggest that the 0.28 × 106-dalton RNA component is the cistron for coat protein, and that it and other RNAs associated with TYMV infection are encapsidated. 相似文献
77.
78.
79.
K A Matthews 《Psychosomatic medicine》1992,54(1):1-9
Menopause is a reproductive milestone in a woman's life around which many different myths have developed. We reviewed three sets of myths that middle-aged premenopausal women hold and evaluated those myths according to scientific data from our own work and that of others. First, middle-aged women expect to experience depression, irritability, and vasomotor symptoms during the menopause. It appears that the vast majority of postmenopausal women do not experience depression, but do experience vasomotor symptoms that are uncomfortable and may have secondary effects on psychological well being, especially during the perimenopause. Second, middle-aged women believe that holding negative expectations about the menopause affects the quality of the menopausal experience. Indeed, that appears to be the case, perhaps because myths can function as self-fulfilling prophecy. The third myth is that there are no important changes that occur during the menopause. That is incorrect. Estrogen deficiency during the menopause sets the stage for substantial changes in risk for CHD, which becomes clinically apparent later in life. We discussed how estrogen deficiency may influence both lipids and lipoprotein levels and the magnitude of neuroendocrine and cardiovascular respond to mental stress. That latter pathway is of particular interest because middle-aged women may be exposed more often to interpersonal stress and may respond more emotionally to it, relative to men, suggesting a potential interactive effect of the decline in reproductive hormones and co-occurring social and psychological changes during the menopausal period. This discussion of the myths and realities of the menopause has deliberately not been exhaustive.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
80.
The obstetric outcome of singleton pregnancies following in-vitro fertilization/gamete intra-Fallopian transfer 总被引:1,自引:11,他引:1
Wang Jim X.; Clark Anne M.; Kirby Christine A.; Philipson Gregory; Petrucco Oswald; Anderson Graham; Matthews Colin D. 《Human reproduction (Oxford, England)》1994,9(1):141-146
The present study compares 465 singleton live deliveries fromin-vitro fertilization/gamete intra-Fallopian transfer (IVF/GIFT)pregnancies with a large control population to evaluate theincidence of pre-term delivery and small for gestational age(SGA) or very small for gestation age (VSGA) babies resultingfrom IVF/GIFT pregnancies. Overall the incidence of SGA or VSGAfrom an IVF/GIFT pregnancy is higher than from the normal obstetricpopulation (SGA odds ratio 1.76, 95% confidence interval (CI):1.382.25 and VSGA odds ratio 1.61, 95% CI: 1.052.46)particularly among primiparous women (SGA odds ratio 1.99, 95%CI: 1.253.16 and VSGA odds ratio 1.97, 95% CI: 1.492.62).After stratifying by the cause of infertility, only women withunexplained infertility had a significantly higher proportionof SGA/VSGA babies. There was a significantly higher incidenceof pre-term deliveries among the young primiparae (odds ratio5.02, 95% CI: 3.098.13). Thus the excess risk of deliveringa SGA/VSGA baby and pre-term delivery from an IVF/GIFT pregnancyseems to be largely confined to women with unexplained infertilityand young primiparae. 相似文献