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Double-labelling and electron microscopy were used to assess the distribution of GABAergic synapses made onto the neurites of spiking local interneurones in the locust. The aims were to determine the sites of inputs mediating inhibition of the spiking local interneurones and to ascertain the relative abundance of such inputs. This information should allow us to understand better the integrative properties of these spiking local interneurones and the role of inhibition in shaping their receptive field properties or in fine tuning their spike-mediated outputs. Spiking interneurones in a midline population were labelled by intracellular injection of horseradish peroxidase after physiological characterisation. Colloidal gold immunocytochemistry was then used on ultrathin sections of these neurones with a polyclonal antibody raised against GABA. Most GABAergic (inhibitory) input synapses onto the interneurones are made on their ventral neurites, which also receive afferent (excitatory) inputs. These inhibitory inputs to the ventral neurites constitute 43% of the identifiable synapses. Relatively few GABAergic inputs were found onto the dorsal neurites, which are predominantly the sites of output synapses from these interneurones. These results suggest that much synaptic integration takes place in the ventral field of branches and that GABA-mediated presynaptic inhibitory control of spike-mediated outputs from the dorsal neurites is unlikely to occur. © 1993 Wiley-Liss, Inc.  相似文献   
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Lasalocid, sinefungin, and dehydroepiandrosterone were tested for anticryptosporidial activity with an immunodeficient mouse model at doses that have been reported effective when tested with immunosuppressed rodent models. Small but significant reductions in oocyst excretion were only observed under some conditions with lasalocid and dehydroepiandrosterone, but sinefungin had no effect.  相似文献   
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Multimodality treatment of locally advanced breast carcinoma   总被引:1,自引:0,他引:1  
Forty patients with 41 locally advanced breast lesions at stages IIIA and IIIB and the inflammatory stage were treated with combined-modality therapy from July 1980 to August 1985. Treatment included induction chemotherapy consisting of three cycles of fluorouracil, doxorubicin hydrochloride, and cyclophosphamide, followed by mastectomy in those patients whose lesions were operable (n = 28), and resumption of chemotherapy. Nine patients received postoperative radiation therapy. The mean follow-up was 34 months. Greater than 50% reduction in tumor size was achieved in 72% of patients after three cycles of chemotherapy. Overall, local control was achieved in 85% of patients with 59% survival and 53% disease-free survival, while 10% of patients developed local recurrences. Excluding lymphedema of the upper extremity (n = 2) and inflammatory carcinomas (n = 4), local control was achieved in 96% of patients, with 75% survival and 68% disease-free survival, while 4% of patients developed local recurrences. The rate of disease-free survival was 71% in patients with partial response to chemotherapy, contrasted with 43% in patients who did not respond or only minimally responded to chemotherapy. Actuarial five-year survival, based on life-table analysis, was calculated to be 46% for the group overall, 58% for the group excluding lymphedema of the upper extremity and inflammatory carcinoma, and 56% for the 28 patients undergoing mastectomy.  相似文献   
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Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future.  相似文献   
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Tumor vascular signals in renal masses: detection with Doppler US   总被引:3,自引:0,他引:3  
Ramos  IM; Taylor  KJ; Kier  R; Burns  PN; Snower  DP; Carter  D 《Radiology》1988,168(3):633-637
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.  相似文献   
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