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101.
Synaptic actions of peripheral nerve impulses upon Deiters neurones via the mossy fibre afferents 下载免费PDF全文
1. The cerebellar integration of sensory inputs to Deiters neurones was investigated in decerebrate cats. In some preparations decerebration was combined with transection of the olivocerebellar fibres.2. In the latter preparations peripheral nerve impulses generally produced a response consisting of a sequence of the following post-synaptic potentials: (i) an initial e.p.s.p. (d(1)), (ii) early i.p.s.p. (h(1)), (iii) later i.p.s.p. (h(2)).3. The mean latencies of d(1), h(1) and h(2) were 5.7, 7.3 and 9.8 msec from the forelimb nerves, and 7.5, 9.0 and 13.4 msec from the hind limb nerves, respectively.4. The stimulus intensity-response relation indicates that the Group I muscle afferents as well as the low threshold cutaneous afferents contribute to the response.5. In the preparations with the intact inferior olive there were additional components of the post-synaptic potentials: a later e.p.s.p. (d(2)) and another later i.p.s.p. (h(3)), their mean latencies being 15.3 and 19.7 msec from the forelimb nerves, and 18.0 and 21.3 msec from the hind limb nerves, respectively.6. The d(1) and h(2) components were attributed to the mossy fibre afferents and d(2) and h(3) to the climbing fibres; d(1) and d(2) were due to excitation through the collaterals of the mossy and climbing fibres, and h(2) and h(3) to inhibition from Purkyne cells activated by the mossy and climbing fibres, respectively. h(1) was too early to be produced through the cerebellum, and was probably mediated by inhibitory neurones in the reticular formation. 相似文献
102.
Carlson DJ Stewart RD Li XA Jennings K Wang JZ Guerrero M 《Physics in medicine and biology》2004,49(19):4477-4491
Parallel in vitro and in vivo studies provide insight into the relationship between clinical response and intrinsic cellular radiosensitivity and may aid in the development of predictive assays. Compilations of radiosensitivity parameters from in vitro experiments can also be used to examine the potential effectiveness of alternative or new treatment plan designs until enough clinical data become available to directly estimate the requisite radiosensitivity parameters. In this work, survival data for six prostate cancer cell lines (ten datasets total) have been extracted from the literature and re-analysed using the linear-quadratic (LQ) survival model. The paired bootstrap technique for regression is used to compute 95% confidence intervals for the estimated radiosensitivity parameters. LQ radiosensitivity parameters derived from the in vitro data are then compared to radiosensitivity parameters derived from clinical data for prostate cancer. Estimates of alpha range from 0.09 to 0.35 Gy(-1) (all cell lines), and the alpha/beta ratio ranges from 1.09 to 6.29 Gy (all cell lines). Point estimates of the repair half-time (PPC-1, TSU-Pr1, PC-3 and DU-145 cell lines) range from 5.7 to 8.9 h (95% confidence interval from 0.26 h to 10.7 h). Differences in the radiosensitivity parameters determined from the data reported by different laboratories are as large as or larger than the differences in radiosensitivity parameters observed among the various prostate cell lines. The reported studies demonstrate that even seemingly small corrections for dose rate effects, such as those expected in high dose rate (HDR) experiments, can sometimes have a significant impact on estimates of alpha and alpha/beta. By neglecting dose rate effects in the analysis of HDR experiments, estimates of the alpha/beta, ratio may be too high by factors as large as 1.3 to 6.2. The half-time for repair derived from the in vitro experiments appears significantly larger (slower repair rate) than estimates derived from the clinical data. However, the prostate radiosensitivity parameters alpha and alpha/beta may be approximately the same in vitro and in vivo. Most of the in vitro data are consistent with an alpha/beta ratio for prostate cancer less than 3 or 4 Gy. 相似文献
103.
Elizabeth Allen Judy Zerzan Christine Choo David Shenson Somnath Saha 《Academic medicine》2005,80(2):125-128
The changing health care marketplace requires new graduates to be familiar with complex health systems. Since 1999 the Oregon Health & Science University internal medicine residency program has offered a seminar-based health systems curriculum, but residents lacked an opportunity to actively apply learned concepts. To achieve this goal, the authors developed a second curricular component, the Health Systems Independent Study Project (HSISP). The HSISP is a self-directed assessment of a health care system or delivery issue residents complete in their third year. The curriculum was implemented in 2001 with goals of gaining a focused understanding of a health systems concept and building related skills. Residents present their study projects to all curriculum participants. Topics addressed so far include adherence to coronary artery disease guidelines in a defined population, screening strategies for lung cancer, resident burnout, and many others. Residents have found that these projects enhance their systems knowledge, help them link systems-based-practice concepts to clinical practice, and foster opportunities for networking and early career development. 相似文献
104.
M.D. F.R.C.P. Bernard J. Fernandes M.D. M.Sc. F.R.C.P. H. Allen Gardner M.D. Ph.D. F.R.C.P. Yvan C. Bedard 《Human pathology》1980,11(6):683-685
The autopsy of an infant with the 4p- or Wolf-Hirschhorn syndrome revealed visceral abnormalities not previously described, i.e., agenesis of the gallbladder and spleen. The parent's chromosomes were normal. 相似文献
105.
Epidemiology of group C rotavirus infection in Western New York women of childbearing age. 总被引:1,自引:1,他引:1 下载免费PDF全文
M Riepenhoff-Talty K Morse C H Wang C Shapiro J Roberts M Welter M Allen M J Evans T D Flanagan 《Journal of clinical microbiology》1997,35(2):486-488
Umbilical cord serum samples (380), an average of 10 per month for 3 years (1990 to 1992), were tested by indirect immunofluorescence assay for group C rotavirus immunoglobulin G. Thirty percent were positive, suggesting that approximately one-third of women of childbearing age in western New York have experienced group C rotavirus infection. 相似文献
106.
Human Lyme arthritis and the immunoglobulin G antibody response to the 37-kilodalton arthritis-related protein of Borrelia burgdorferi 下载免费PDF全文
Salazar CA Rothemich M Drouin EE Glickstein L Steere AC 《Infection and immunity》2005,73(5):2951-2957
In Borrelia burgdorferi-infected C3H-scid mice, antiserum to a differentially expressed, 37-kDa spirochetal outer-surface protein, termed arthritis-related protein (Arp), has been shown to prevent or reduce the severity of arthritis. In this study, we determined the immunoglobulin G (IgG) antibody responses to this spirochetal protein in single serum samples from 124 antibiotic-treated human patients with early or late manifestations of Lyme disease and in serial serum samples from 20 historic, untreated patients who were followed longitudinally from early infection through the period of arthritis. These 20 patients were representative of the spectrum of the severity and duration of Lyme arthritis. Among the 124 antibiotic-treated patients, 53% with culture-proven erythema migrans (EM) had IgG responses to recombinant glutathione S-transferase (GST)-Arp, as did 59% of the patients with facial palsy and 68% of those with Lyme arthritis. In addition, 75 to 80% of the 20 past, untreated patients had reactivity with this protein when EM was present, during initial episodes of joint pain, or during the maximal period of arthritis. There was no association at any of these three time points between GST-Arp antibody levels and the severity of the maximal attack of arthritis or the total duration of arthritis. Thus, after the first several weeks of infection, 60 to 80% of patients had IgG antibody responses to GST-Arp, but this response did not correlate with the severity or duration of Lyme arthritis. 相似文献
107.
Comparison of Ashdown's medium, Burkholderia cepacia medium, and Burkholderia pseudomallei selective agar for clinical isolation of Burkholderia pseudomallei 下载免费PDF全文
Peacock SJ Chieng G Cheng AC Dance DA Amornchai P Wongsuvan G Teerawattanasook N Chierakul W Day NP Wuthiekanun V 《Journal of clinical microbiology》2005,43(10):5359-5361
Ashdown's medium, Burkholderia pseudomallei selective agar (BPSA), and a commercial Burkholderia cepacia medium were compared for their abilities to grow B. pseudomallei from 155 clinical specimens that proved positive for this organism. The sensitivity of each was equivalent; the selectivity of BPSA was lower than that of Ashdown's or B. cepacia medium. 相似文献
108.
Zonal distribution of glomerular collapse in renal allografts: possible role of vascular changes 总被引:5,自引:0,他引:5
Collapsing glomerulopathy (CG), an aggressive variant of focal segmental glomerular sclerosis, is a renal disease with severe proteinuria and rapidly progressive renal failure. The pathogenesis of CG is unknown. It strongly resembles human immunodeficiency virus (HIV)-associated nephropathy, but the patients are HIV negative. The characteristic glomerular lesion is capillary loop collapse with prominent podocytes filling Bowman's space. Interestingly, these glomerular changes are usually associated with severe tubulointerstitial injury, including tubular epithelial degenerative changes, microcystic dilation of several tubules, and interstitial inflammatory cell infiltrate. Recently, it became evident that the morphologic pattern of CG may appear not only in native kidneys, but also de novo in renal allografts, and that the pattern of CG in renal transplants is not always associated with severe proteinuria. Studies describing CG in renal allografts are all based on biopsies. We report 3 allograft nephrectomy specimens that showed a zonal distribution of the characteristic collapsing glomerular changes with associated tubulointerstitial injury. All 3 kidneys had obliterative vascular changes. One nephrectomy specimen had chronic obliterative transplant arteriopathy, 1 had acute vascular rejection, and 1 had thrombotic microangiopathy. None of the patients had severe proteinuria. Our cases suggest that the morphologic pattern of CG in renal allografts may not represent the same disease process as CG in native kidneys and provide further evidence that collapsing glomerular changes do not define the disease entity of CG, but rather represent a pattern of renal injury. Among other factors, hemodynamic disturbance may play a role in the development of the pattern of CG in renal allografts. 相似文献
109.
110.
Nakabayashi T Sakata KM Sakata A Kong L Lau CA Letterio JJ Vela-Roch N Talal N Dang H 《Inflammation》2001,25(2):69-73
The TGF-1(–/–) mouse is a murine model for systemic autoimmune disease. The aim of this study is to elucidate the immunological mechanism that leads to multifocal tissue inflammation and autoantibody production in TGF-1(–/–) mice. Heart, lung, liver, and salivary gland from TGF-1(–/–) were assessed for CD154 expression by RT-PCR and immunohistochemistry. Compared to wild-type littermates, CD154 expression was elevated in all tissues studied. Furthermore, IL-12 mRNA was expressed in the salivary gland and heart of TGF-1(–/–) mice and not in wild-type littermates. This suggests that the CD154 pathway is activated in these tissues. This shows that TGF-1 regulates CD154 expression leading to spontaneous IL-12 production and autoimmunity. 相似文献