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71.
目的 探索LDH实验检测细胞活力的可行性。方法 原代培养骨髓细胞和软骨细胞,用LDH实验测定上述两组细胞的活力,并与镜下活体观察到细胞的生长状况相比较。与目前比较成熟的测定细胞活力的MTS实验的测得的值相比较。结果 LDH实验对上述两组细胞的活力的测定结果与镜下活体观察到的结果相符合。与MTS实验的测得的结果经统计学处理无显著差异。结论 LDH实验可用于细胞活力的直接测定,而对活细胞的生存、繁殖无影响。 相似文献
72.
73.
G E Leighton T Griesbacher R G Hill J Hughes 《European journal of pharmacology》1989,161(2-3):255-258
The reduction in food intake induced by i.p. injections of the cholecystokinin (CCK) analogue caerulein was antagonised by a low dose (0.25 mumol/kg s.c.) of the selective CCK antagonist L-364,718. To block the anorectic effect of centrally administered caerulein a dose of 25 mumol/kg of L-364,718 was required, demonstrating that central CCK receptors can be blocked effectively in the rat by choosing appropriate doses of L-364,718. 相似文献
74.
75.
To study the effects of electroconvulsive therapy (ECT) on hormone release, we measured circulating concentrations of adrenocorticotropic hormone (ACTH), prolactin (PRL), growth hormone (GH) and cortisol (CORT) immediately before and at 2 min, 5 min, 15 min, and 30 min following ECT. Compared to pre-ECT concentrations, there were significant increases in post-ECT plasma ACTH, PRL and CORT. GH did not change consistently. No significant difference between unilateral and bilateral ECT was observed. Compared to the first ECT, repeated treatments were associated with a significant decrease in the magnitude of hormone surge. These hormonal changes induced by ECT may reflect changes at the neurotransmitter level. 相似文献
76.
Permeability of human brain tumor to 99mTc-gluco-heptonate and 99mTc-albumin. Implications for monoclonal antibody therapy 总被引:1,自引:0,他引:1
The variable penetration of chemotherapeutic drugs into brain and tumor is more dependent upon lipid solubility than upon size. In contrast, the molecular weight of virus- and tumor-specific monoclonal antibodies appears to limit uptake. The authors have studied eight patients with malignant brain tumors in order to compare tumor uptake of an iodinated contrast agent evaluated by computerized tomography scanning with uptake of the low and high molecular weight imaging agents technetium-99m (99mTc)-glucoheptonate and 99mTc-albumin, respectively, measured by radionuclide brain scanning. The agent 99mTc-labeled albumin was chosen for evaluation because its molecular weight (68,000) is similar to that of the most clinically promising monoclonal antibody fragment, the immunoglobulin (Ig) G Fab monomeric fragment. The radionuclide brain scans in the eight patients showed highly variable permeability of brain tumor to these markers, with uptake of the high molecular weight marker in the tumor being much less than that of the low molecular weight radionuclide. A clinical implication of these studies is that the success of monoclonal antibody therapy in the treatment of malignant brain tumors may require techniques to increase permeability of the blood-brain barrier and blood-tumor barrier to protein. 相似文献
77.
Michael P Hill Erwan Bezard Steven G McGuire Alan R Crossman Jonathan M Brotchie Ann Michel Renee Grimée Henrik Klitgaard 《Movement disorders》2003,18(11):1301-1305
Long-term dopamine replacement therapy of Parkinson's disease leads to the occurrence of dyskinesias. Altered firing patterns of neurons of the internal globus pallidus, involving a pathological synchronization/desynchronization process, may contribute significantly to the genesis of dyskinesia. Levetiracetam, an antiepileptic drug that counteracts neuronal (hyper)synchronization in animal models of epilepsy, was assessed in the MPTP-lesioned marmoset model of Parkinson's disease, after coadministration with (1) levodopa (L-dopa) or (2) ropinirole/L-dopa combination. Oral administration of levetiracetam (13-60 mg/kg) in combination with either L-dopa (12 mg/kg) alone or L-dopa (8 mg/kg)/ropinirole (1.25 mg/kg) treatments was associated with significantly less dyskinesia, in comparison to L-dopa monotherapy during the first hour after administration. Thus, new nondopaminergic treatment strategies targeting normalization of abnormal firing patterns in basal ganglia structures may prove useful as an adjunct to reduce dyskinesia induced by dopamine replacement therapy without affecting its antiparkinsonian action. 相似文献
78.
OBJECTIVE: To determine the feasibility and effectiveness of laparoscopically assisted hysterectomy. DESIGN: A prospective study of the planned surgical procedure was carried out by two teams, each with two gynaecologists, who were experienced in operative laparoscopy. SETTING: The operations were carried out in a private hospital, where advanced operative laparoscopy equipment was available. PATIENTS: Seventeen patients were selected for the procedure, all of whom required hysterectomy for symptoms of pain or menorrhagia in association with uterine or other pelvic disease. Patients with carcinoma or uterine enlargement beyond 12 cm were excluded. PROCEDURE: Laparoscopically assisted hysterectomy was carried out by means of a video monitor, uterine manipulation by vaginal instrumentation, three or four abdominal punctures of less than 1 cm, and bipolar diathermy to secure vascular pedicles. The uterus was removed from the vagina by cutting vaginal skin and the cardinal ligaments. RESULTS: The operating time was 90-220 min, the blood loss was 30-200 mL, and the hospital stay lasted two to five days and convalescence two to four weeks. No serious complications occurred. CONCLUSIONS: Laparoscopically assisted hysterectomy may be valuable when adnexal or uterine abnormalities are present and vaginal hysterectomy is either contraindicated or more difficult. The procedure requires special equipment and may only be carried out by experienced gynaecological operative laparoscopists. Its acceptance will depend upon reducing the operating time to less than 90 min. It has the advantage of reducing the duration of hospital stay and the duration of convalescence when compared with abdominal hysterectomy. 相似文献
79.
80.
Helene Z. Hill Maimu Ohanian George J. Hill Richard Winne 《Journal of surgical oncology》1987,34(4):264-267
Intraoperative radiation therapy (IORT) research is limited by the lack of small-animal models. We have implanted B16 melanoma into mouse kidneys, which we subsequently operated upon and irradiated with beta rays from a 90Sr ophthalmic applicator. The IORT has effectively prolonged survival and produced some cures. The strategy should be applicable to other murine tumors and to other internal implantation sites. 相似文献