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61.
62.
M. J. Kelly R. L. Moss C. A. Dudley C. P. Fawcett 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1977,30(1):43-52
Summary The purpose of this study was to determine the specificity of the response of medial preoptic-septal neurons (mPOA-S) to microelectrophoresed 17-estradiol hemisuccinate (17E2S). In vitro studies were conducted initially to determine the release of the labeled 17E2S from multibarrel glass micropipettes. Subsequently, an isomer of 17E2S, 17-estradiol hemisuccinate (17E2S), was synthesized and purified. Thirty-six mPOA-S neurons from normal cycling female rats were tested with both 17E2S and 17E2S. Twelve of these units responded with inhibition to 17E2S, while none responded to 17E2S. Furthermore, fifty extrahypothalamic (cortical, hippocampal, thalamic) neurons were tested with 17E2S. The majority (N = 45) showed no response, three showed excitation and two inhibition to the microelectrophoresed steroid ester. These findings suggest that a specific receptor mechanism is responsible for the changes in mPOA-S unit activity, and that these effects may be important in the regulation of reproductive events.Supported by NIH Grant NS10434-END, awarded to R.L. MossPresently an NIH Postdoctoral Fellow at Max-Planck Institute for Biophysical Chemistry, Göttingen, West GermanyRecipient of an USPHS Career Development Award No. HD00146 相似文献
63.
Chronic Inflammatory Demyelinating Polyneuropathies (CIDP) are characterized by demyelination of peripheral nerves with mononuclear cell infiltrates, electrical conduction slowing or block and elevated cerebrospinal fluid protein with no cells. An immune mediated pathogenesis has been suggested. Immune suppressive therapy, as well as plasmapheresis and intravenous immunoglobulins have been used with variable success. Our objective was to review our results of plasma exchange in this disease in 20 patients with very different underlying diseases, none of them eligible for the Canadian CIDP plasmapheresis study, and define certain guidelines of predictability for the effectiveness of plasma exchange. Five patients had monoclonal gammopathies of unknown significance, two had lung cancer, one breast cancer, one hairy cell leukemia and later carcinoma of the pancreas; two had hepato-splenomegaly and hemolytic anemia; nine were idiopathic (two with autoimmune markers). Plasmapheresis varied from 4 to 31 plasma volumes and procedures with a median of 12, always with 5% albumin. Two excellent responses, one very good, two moderate transient and 12 had no change in clinical or conduction status. Best response occurred in paraproteinemias. Thus immune modulation with plasma exchange may be useful in CIDPs with paraproteinemias and autoimmune manifestations. 相似文献
64.
Guidelines for the conduct of clinical trials for spinal cord injury (SCI) as developed by the ICCP panel: clinical trial outcome measures 总被引:3,自引:0,他引:3
Steeves JD Lammertse D Curt A Fawcett JW Tuszynski MH Ditunno JF Ellaway PH Fehlings MG Guest JD Kleitman N Bartlett PF Blight AR Dietz V Dobkin BH Grossman R Short D Nakamura M Coleman WP Gaviria M Privat A;International Campaign for Cures of Spinal Cord Injury Paralysis 《Spinal cord》2007,45(3):206-221
An international panel reviewed the methodology for clinical trials of spinal cord injury (SCI), and provided recommendations for the valid conduct of future trials. This is the second of four papers. It examines clinical trial end points that have been used previously, reviews alternative outcome tools and identifies unmet needs for demonstrating the efficacy of an experimental intervention after SCI. The panel focused on outcome measures that are relevant to clinical trials of experimental cell-based and pharmaceutical drug treatments. Outcome measures are of three main classes: (1) those that provide an anatomical or neurological assessment for the connectivity of the spinal cord, (2) those that categorize a subject's functional ability to engage in activities of daily living, and (3) those that measure an individual's quality of life (QoL). The American Spinal Injury Association impairment scale forms the standard basis for measuring neurologic outcomes. Various electrophysiological measures and imaging tools are in development, which may provide more precise information on functional changes following treatment and/or the therapeutic action of experimental agents. When compared to appropriate controls, an improved functional outcome, in response to an experimental treatment, is the necessary goal of a clinical trial program. Several new functional outcome tools are being developed for measuring an individual's ability to engage in activities of daily living. Such clinical end points will need to be incorporated into Phase 2 and Phase 3 trials. QoL measures often do not correlate tightly with the above outcome tools, but may need to form part of Phase 3 trial measures. 相似文献
65.
Natural orifice transluminal endoscopic surgery (NOTES) is an emerging experimental alternative to conventional surgery. NOTES eliminates abdominal incisions and incision‐related complications by combining endoscopic and laparoscopic techniques to diagnose and treat abdominal pathology. Since the first NOTES was reported by Kalloo et al. in 2004, significant achievements in the laboratory have occurred. Clinical use in humans has been limited, but several cases and one small clinical trial were published recently. As a further technical revolution in minimally invasive surgery, NOTES has the promising potential to be safer, less invasive, provide better cosmesis and possibly be more cost‐effective. The purpose of the present article was to review the development and current status of NOTES and highlight important advances associated with this innovative approach. 相似文献
66.
Enhanced axonal regeneration following combined demyelination plus schwann cell transplantation therapy in the injured adult spinal cord. 总被引:9,自引:0,他引:9
We have treated spinal cord injured rats with demyelination plus Schwann cell transplantation and assessed neurite outgrowth in a quantifiable model of axonal regeneration. Axonal injuries of differing severity were induced in the dorsal funiculus of adult rats using a micromanipulator-controlled Scouten knife. Demyelinated regions were produced so as to overlap with the injury site by the injection of galactocerebroside antibodies plus complement one segment cranial to the axonal injury site. Schwann cells were isolated from the sciatic nerve, expanded in vitro, and transplanted into the injury site 1 day later. Animals were killed after an additional 7 days. Schwann cells were evenly distributed throughout the region of demyelination, which extended 6-7 mm cranial to the axonal injury site. The severity of axonal injury was quantified by counting degenerate axons in transverse resin sections. The degree of axonal regeneration was assessed by an electron microscopic analysis of growth cone frequency and distribution relative to the site of axonal injury. Quantification of growth cones at a distance from the site of axonal injury indicated a strong linear relationship (P < 0.001) between the number of growth cones and the number of severed axons; the ratio of growth cones to severed axons was increased by 26.5% in demyelinated plus transplanted animals compared to demyelinated animals without a transplant. Furthermore, only the demyelinated plus transplanted animals contained growth cones associated with myelin in white matter immediately outside of the region of complete demyelination. Growth cones were absent in transplanted-only animals at a distance from the site of axonal injury. These findings indicate that combined demyelination plus Schwann cell transplantation therapy enhances axonal regeneration following injury and suggests that growth cones are able to overcome myelin-associated inhibitors of neurite outgrowth in the presence of trophic support. 相似文献
67.
Background
Fractures of the intertrochanteric hip are common and the treatment of unstable fractures generally requires an operative approach. In elderly patients, osteoporosis makes internal fixation problematic and frequently contributes to failed fixation and poor clinical results. We have attempted to apply the Less Invasive Stabilization System (LISS) in reverse position for the repair of intertrochanteric hip fractures in elderly patients with osteoporotic bones. A retrospective review is presented of the cases of 28 elderly patients with stable and unstable fractures of the intertrochanteric hip treated using the reverse LISS. 相似文献68.
Bertha Nhlema Simwaka George Bello Hastings Banda Rhehab Chimzizi Bertel SB Squire Sally J Theobald 《International journal for equity in health》2007,6(1):24
Background
Until 2005, the Malawi National Tuberculosis Control Programme had been implemented as a vertical programme. Working within the Sector Wide Approach (SWAp) provides a new environment and new opportunities for monitoring the equity performance of the programme. This paper synthesizes what is known on equity and TB in Malawi and highlights areas for further action and advocacy. 相似文献69.
Mills GD Lindeman JA Fawcett JP Herbison GP Sears MR 《International journal of epidemiology》2000,29(2):280-284
BACKGROUND: The factors that cause the allergic sensitization and inflammation in asthma still remain to be clarified. A role for Chlamydia pneumoniae has been suggested although serological studies have produced conflicting findings. This study aims to clarify the relationship between asthmatic variables and C. pneumoniae serological status. METHODS: A case-control study was undertaken on an asthma-enriched subset from a longitudinal birth cohort. In all, 198 subjects (96 with self-reported asthma) had C. pneumoniae serology (microimmunofluorescence [MIF] IgG, IgA) undertaken at age 11 and age 21 and assessment made in relation to a number of asthma variables. RESULTS: The only statistically significant finding was in subjects self-reporting asthma at age 21 who had evidence of lower IgG titres (P = 0.046), a finding in the opposite direction to that expected from the hypothesis. Subjects with high IgG titres (> or =128) were less likely to have reported ever having asthma; odds ratio (OR) = 0.29, (95% CI: 0.10-0.87). No association existed between symptoms suggestive of asthma in the previous 12 months and either IgG (P = 0.127) or IgA (P = 0.189) antibody titres at age 21. Likewise, no association was found between symptoms suggestive of asthma in the previous two years and C. pneumoniae IgG antibody titre (P = 0.81) at age 11. There was no evidence of an association with any of the other variables examined at either age 11 or age 21. These included use of inhaled steroids, serum IgE levels, airway responsiveness, skin test evidence of atopy, or smoking status. CONCLUSION: The results of this study suggest that C. pneumoniae infection when diagnosed by MIF serology is not a major risk factor for the development of asthma in children and young adults. The study has not, however, addressed the role this organism may play in specific asthmatic subsets or asthma exacerbations. 相似文献
70.
D. C. Gotley J. Fawcett M. D. Walsh J. A. Reeder D. L. Simmons T. M. Antalis 《British journal of cancer》1996,74(3):342-351
Increased expression of alternatively spliced variants of the CD44 family of cell adhesion molecules has been associated with tumour metastasis. In the present study, expression of alternatively spliced variants of CD44 and their cellular distribution have been investigated in human colonic tumours and in the corresponding normal mucosa, in addition to benign adenomatous polyps. The expression of CD44 alternatively spliced variants has been correlated with tumour progression according to Dukes'' histological stage. CD44 variant expression was determined by immunohistochemisty using monoclonal antibodies directed against specific CD44 variant domains together with RT-PCR analysis of CD44 variant mRNA expression in the same tissue specimens. We demonstrate that as well as being expressed in colonic tumour cells, the full range of CD44 variants, CD44v2-v10, are widely expressed in normal colonic crypt epithelium, predominantly in the crypt base. CD44v6, the epitope which is most commonly associated with tumour progression and metastasis, was not only expressed by many benign colonic tumours, but was expressed as frequently in normal basal crypt epithelium as in malignant colonic tumour cells, and surprisingly, was even absent from some metastatic colorectal tumours. Expression of none of the CD44 variant epitopes was found to be positively correlated with tumour progression or with colorectal tumour metastasis to the liver, results which are inconsistent with a role for CD44 variants as indicators of colonic cancer progression. 相似文献