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1.
In primary visual cortex of hooded rats, pyramidal cells in layer V may be classified as long, medium, or short, on the basis of the layer in which the apical dendrite terminates. The present study determines which of these types of pyramidal cells project to the superior colliculus. Two different strategies were used to label corticotectal cells with horseradish peroxidase (HRP). In the first set of experiments, a large number of corticotectal cells were labeled by retrograde transport following injection of HRP into the superior colliculus. In the second set of experiments, single unit recording was used to identify corticotectal cells physiologically by antidromic activation from the superior colliculus. These cells were then impaled and labeled by intracellular iontophoresis of HRP. The results from both techniques suggest that only long pyramidal cells send an axon to the superior colliculus. These cells are distinguished by an apical dendrite that extends into layer I. We conclude that in hooded rats corticotectal cells in primary visual cortex are the long pyramids in layer V. 相似文献
2.
Chondrons were isolated from human and canine osteoarthritic cartilage using low-speed homogenization techniques. Changes in chondron morphology were evaluated using differential interference-contrast microscopy, phase-contrast microscopy, and histochemical and ultrastructural methods. Chondrocyte viability was assessed using fluorescein diacetate staining, and chondron metabolism was investigated using autoradiography. The results suggest that initial changes in the collagen and proteoglycan distribution within the chondron are followed by chondrocyte proliferation to form clusters. These techniques offer the potential to study cell matrix interactions in degenerative osteoarthritis. 相似文献
3.
This paper reports the results of a survey in which pregnant women in London and Edinburgh were asked about their knowledge and understanding of the recent recommendations of expert committees (James, 1983; DHSS, 1984). In general, Londoners had a better understanding, although in both regions manual groups were less knowledgeable, with the Edinburgh manual group the least well informed. 相似文献
4.
5.
Localisation of a pulmonary autoantigen in cryptogenic fibrosing alveolitis. 总被引:2,自引:1,他引:1 下载免费PDF全文
BACKGROUND--Cryptogenic fibrosing alveolitis (CFA) is believed to have an immunological pathogenesis with a persisting inflammatory reaction to an as yet unidentified pulmonary antigen(s). A high frequency of IgG autoantibodies has previously been found in the plasma of patients with CFA to an extractable 70-90 kDa lung antigen by Western blotting. Preliminary immunohistochemical studies with patient IgG had indicated that the target protein(s) might be associated with alveolar epithelial lining cells which have previously been suggested as the site of immunological attack in CFA. METHODS--In order to confirm this finding immunohistochemical analysis and Western blotting were performed on a human type II alveolar cell line (A549) using CFA patient plasma. In order to study further the distribution of the antigen, antibodies were raised in a rabbit to the partially purified 70-90 kDa CFA lung protein. RESULTS--The results showed that the human CFA autoantibody recognised a 70-90 kDa protein with a cytoplasmic distribution present in the A549 cells, confirming previous observations. The immune rabbit IgG recognised a protein of similar molecular weight by Western blotting of protein derived from lung biopsy samples of patients with CFA and A549 cells. In addition it immunoprecipitated protein(s) of this molecular weight from lung biopsy protein extracts from patients with CFA. The precipitated protein(s) were found to cross-react with the autoantibody found in the plasma of patients with CFA. Immunohistochemical analysis with immunised rabbit antibody revealed positive staining of type I and II alveolar epithelial lining cells in CFA. A similar pattern of epithelial staining was also observed with the rabbit IgG on biopsy specimens of lung from patients with sarcoidosis and control lung tissue, although this was more focal and less intense. No positive staining was seen on sections from a number of non-pulmonary tissues (colon, liver, kidney, tonsil, lymph node, skin, cervix). Cytoplasmic staining of the A549 cell line was also detected. CONCLUSIONS--The 70-90 kDa protein recognised by autoantibodies in patients with CFA is associated with pulmonary epithelial lining cells. The immune rabbit IgG produced appears to recognise antigen by Western blotting and immunohistochemical staining of lung tissue in a similar pattern to the patient autoantibodies. Immunohistochemical data obtained with this antibody suggest that the putative autoantigen against which patients with CFA mount a humoral immune response may be endogenous and specific to the lung. 相似文献
6.
The objective of this blinded, randomized, prospective study was to assess whether supplementation of normal diet with omega-3 polyunsaturated fatty acids can reduce angiographically defined restenosis following coronary angioplasty. The study included all patients undergoing coronary angioplasty in this institution between January 1988 and January 1989. One hundred and twenty patients enrolled, 60 in each treatment group. All were randomized to either supplementation of normal diet with 3 g of omega-3 polyunsaturated fatty acids per day started 1-2 days prior to angioplasty and continued for 6 months (treatment group), or to receive standard therapy only (control group). Quantitative angiographically defined restenosis was assessed at 6 months post angioplasty. Restenosis occurred in 27.8% (95% CI 18.0-37.7%) of lesions in the treatment group and in 28.3% (CI 16.9-39.7%) of lesions in the control group, but the difference was not statistically significant. The study showed that diet supplemented with 3 g of omega-3 polyunsaturated fatty acids started 1-2 days preceding angioplasty does not reduce angiographically defined restenosis rate. 相似文献
7.
1S,3R-ACPD stimulates and L-AP3 blocks Ca2+ mobilization in rat cerebellar neurons 总被引:10,自引:0,他引:10
A J Irving J G Schofield J C Watkins D C Sunter G L Collingridge 《European journal of pharmacology》1990,186(2-3):363-365
8.
J. Russel Geyer Deborah Schofield Mitchell Berger Jerrold Milstein 《Journal of neuro-oncology》1992,14(3):237-241
We describe a case of cerebellar neuroblastoma with histologic documentation of maturation into a ganglioglioma sixteen months later. Only chemotherapy was administered following the initial surgery and the child is well and disease-free three years following her final surgical procedure. The outcome of this patient supports previous hypotheses that the cerebellar neuroblastoma may be a less malignant tumor than its other primitive neuroectodermal posterior fossa counterparts. Furthermore, this case suggests a role for second-look surgery in the management of selected pediatric brain tumors. 相似文献
9.
N. G. Powell E. J. Threlfall H. Chart S. L. Schofield B. Rowe 《Epidemiology and infection》1995,114(3):403-411
Using pulsed-field gel electrophoresis (PFGE) and 16S rRNA (rrn) analysis (ribotyping), the in vivo derivation of strains of Salmonella enteritidis PTs 9a and 7 from a strain of S. enteritidis PT 4 has been demonstrated. All strains were isolated from a single patient over a 6-week period. Further studies have demonstrated that in terms of pulsed-field profile and ribotype, the genotypes of the patient-derived strains differed from those of the reference strains of the respective phage types. It is concluded that when used in combination, these methods can provide evidence of phylogenetic relationships in apparently unrelated S. enteritidis phage types isolated during pathogenesis of disease. 相似文献
10.
Helen Herrman Bruce Singh Hilary Schofield Robin Eastwood Philip Burgess Virginia Lewis Richard Scotton 《Australian and New Zealand journal of public health》1993,17(3):261-266
Abstract: Informal caregivers are the families and other unpaid caregivers in the home who support people of all ages with severe and chronic mental or physical disabilities. Home care of this sort has been increasing over the past 30 years because of the reduced number of beds in hospitals and nursing homes and increased outpatient and community care. Moreover, with an aging population and increasing rates of disability, the demand for family caregiving will continue to rise. This has important implications for the development of health, community service and social policy. At the same time, however, very little is known about the impact such changes are having on the caregivers of various ages and in various circumstances. The Victorian Health Promotion Foundation is funding a research and intervention program in Melbourne to promote wellbeing and prevent ill-health in caregivers. 相似文献