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71.
The effect of an Egyptian medicinal plant, Cleome droserifolia (Forssk.) Del. on nitric oxide (NO) production in bacillus Calmette-Guérin-induced mouse peritoneal macrophages activated by lipopolysaccharide was investigated in vitro. The methanol extract of C. droserifolia reduced the NO production, and two flavonoids were isolated as the active components. The new one was determined to be 5,4'-dihydroxy-6,7,8,3',5'-pentamethoxyflavone (1) and the other was identified as 5,4'-dihydroxy-6,7,8,3'-tetramethoxyflavone (8-methoxycirsilineol; 2). Compound 1 concentration-dependently suppressed the NO production and was effective at a non-toxic concentration (12.5 micrograms/ml). The suppressive activity of 2 was weaker than that of 1.  相似文献   
72.
Delayed single-photon emission tomograpic (SPET) images after an intravenous bolus injection of iodine-123 iomazenil have been used as a relative map of benzodiazepine receptor binding. We determined the optimal scan time for obtaining such a map and assessed the errors of the map. SPET and blood data from six healthy volunteers and five patients were used. A three-compartment kinetic model was employed in simulation studies and analyses of actual data. The simulation studies suggested that, in the normal brain, the scan time at which a single SPET image best represented the relative receptor binding was 3.0–3.5 h post-injection. This finding was supported by actual data from the volunteers. The simulation studies also suggested that the optimal scan time was not greatly changed by the variability of the input functions, and that the error in the SPET image contrast in the vicinity of the optimal scan time was not increased by changes in the tracer kinetics in the entire brain. The SPET image contrast in the patients at 3.0 h post-injection agreed well with the reference receptor binding estimated by kinetic analysis, with a mean error of 3.6%. These findings support the use of a single SPET image after bolus injection of [123I]iomazenil as a relative map of benzodiazepine receptor binding. For this purpose, a SPET scan time of 3.0-3.5 h post-injection is recommended.  相似文献   
73.
This review reassesses the role of hormonal therapy in breast cancer specifically the sequential or concurrent use of endocrine therapy and the combined use of chemotherapy with endocrine therapy. In advanced disease the sequential use of hormone therapies is generally recommended rather than the combined use of various hormonal agents, though combination hormonal therapy offers advantages in certain subsets of patients. The efficacy of combined chemo-endocrine therapy is questionable. Chemotherapy with estrogenic recruitment is an attractive but still experimental concept. However, in an adjuvant setting there is evidence that combined chemo-endocrine therapy causes a significant increase in disease-free and/or overall survival, particularly in postmenopausal patients with estrogen receptor (Expositive tumors. While hormonal treatment strategies have clearly benefitted from randomized studies, data regarding optimal endocrine therapy are still insufficient.  相似文献   
74.
75.
Kishi HS 《Neurosurgery》2000,47(2):441-5; discussion 445-6
This article recountsOFF (Shimada) Kishi's experience when he was appointed as chief of the First Investigation Committee that evaluated the damage caused by the atom bomb dropped on Hiroshima.  相似文献   
76.
Objective: To evaluate the effect of prednisolone plus low-dose aspirin (PSL/LDA) in women with autoimmune conditions who were enrolled in an IVF-ET program.

Design: A retrospective clinical study.

Setting: In vitro fertilization unit, Niigata University Hospital, Niigata, Japan.

Patient(s): Three hundred seven women who underwent IVF-ET between January 1996 and December 1997.

Intervention(s): Prednisolone (10 mg/d) and aspirin (81 mg/d) were administered to the women with autoantibodies who chose to participate.

Main Outcome Measure(s): Pregnancy and implantation rates with IVF-ET.

Result(s): Women undergoing IVF who had positive antinuclear antibodies, with or without antiphospholipid antibodies, had significantly lower pregnancy and implantation rates than did women without autoantibodies (14.8% versus 21.7% and 6.8% versus 10.4%, respectively). The administration of PSL/LDA to women with antinuclear antibodies significantly improved the outcome of IVF-ET (40.6% pregnancy rate and 20.3% implantation rate).

Conclusion(s): A high proportion of women who are undergoing IVF-ET have autoantibodies, which are associated with poor IVF outcomes. The administration of PSL/LDA to these women may improve their implantation rate.  相似文献   

77.
Thrombolysis with conventional thrombolytic agents prior to percutaneous coronary intervention (PCI) has had no impact on the treatment of acute myocardial infarction (AMI). However, the development of mutant tissue type plasminogen activators (mt-PA) has prompted us to reassess the combination of thrombolysis and PCI. Monteplase is a newly developed mt-PA that can be administered as a single intravenous bolus injection. The results of the COMA (COmbining Monteplase with Angioplasty) trial, suggest that monteplase administration prior to emergent PCI in AMI improves 6-month outcomes and possibly the long-term prognosis of myocardial infarction. Combining monteplase administration on presentation at a community hospital with prompt transfer to a tertiary center for PCI would be an ideal strategy for the treatment of AMI.  相似文献   
78.
Gene expression of antioxidant enzymes in experimental diabetic neuropathy   总被引:6,自引:0,他引:6  
Chronic hyperglycemia results in a large deficit in nerve blood flow. Both autoxidative- and ischemia-induced lipid peroxidation occurs, with resultant peripheral sensory neuropathy in streptozotocin-induced diabetes in the rat. Free radical defenses, especially involving antioxidant enzymes, have been suggested to be reduced, but scant information is available on chronic hyperglycemia. We evaluated the gene expression of glutathione peroxidase, catalase, and superoxide dismutase (cuprozinc and manganese separately) in L4,5 dorsal root ganglion (DRG) and superior cervical ganglion, as well as enzyme activity of glutathione peroxidase in DRG and sciatic nerve in experimental diabetic neuropathy of 3 months and 12 months durations. We also evaluated nerve electrophysiology of caudal, sciatic-tibial, and digital nerves. A nerve conduction deficit was seen in all nerves in experimental diabetic neuropathy at both 3 and 12 months. Gene expression of glutathione peroxidase, catalase, cuprozinc superoxide dismutase, and manganese superoxide dismutase were not reduced in experimental diabetic neuropathy at either 3 or 12 months. Catalase mRNA was significantly increased in experimental diabetic neuropathy at 12 months. Glutathione peroxidase enzyme activity was normal in sciatic nerve. We conclude that gene expression is not reduced in peripheral nerve tissues in very chronic experimental diabetic neuropathy. Changes in enzyme activity may be related to duration of diabetes or due to post-translational modifications.  相似文献   
79.
We investigated the effect of hypothermia on the vasodilatory response of pial arterioles to hemorrhagic hypotension. The cranial window technique was combined with microscopic video recording in an experiment involving 20 cats anesthetized with pentobarbital. The animals were randomly assigned to either a normothermic or a hypothermic group (32 degrees C). Mean arterial pressure (MAP) was reduced in stepwise increments of 10 mm Hg (from 100 to 50 mm Hg) by blood withdrawal. The diameter of small (50-100 microm) and large (100-200 microm) pial arterioles was measured. In the normothermic group (n = 9), small and large arterioles dilated at a MAP of 60 and 50 mm Hg, and at a MAP of 70, 60, and 50 mm Hg, respectively, compared with baseline values obtained at a MAP of 100 mm Hg. In contrast, in the hypothermic group (n = 11), vasodilation of either small or large arterioles was absent. The percentage diameter of small and large arterioles (percentage of control) was significantly lower at a MAP of 70, 60, and 50 mm Hg in the hypothermic group than the normothermic group. Our in vivo study demonstrates that hypothermia impairs autoregulatory vasodilation of pial arterioles in response to hemorrhagic hypotension. IMPLICATIONS: Deliberate mild hypothermia has been proposed as a means of providing cerebral protection during neurosurgical procedures. Our results suggest that cerebral blood flow autoregulation in response to hemorrhagic hypotension may be impaired during hypothermic conditions, indicating the importance of maintaining perfusion pressure during hypothermic therapy to prevent cerebral ischemia.  相似文献   
80.
PURPOSE: We present results of patients with hepatocellular carcinoma (HCC) treated with proton beam therapy. EXPERIMENTAL DESIGN: We reviewed 162 patients having 192 HCCs treated from November 1985 to July 1998 by proton beam therapy with or without transarterial embolization and percutaneous ethanol injection. The patients in the present series were considered unsuitable for surgery for various reasons, including hepatic dysfunction, multiple tumors, recurrence after surgical resection, and concomitant illnesses. The median total dose of proton irradiation was 72 Gy in 16 fractions over 29 days. RESULTS: The overall survival rate for all of the 162 patients was 23.5% at 5 years. The local control rate at 5 years was 86.9% for all 192 tumors among the 162 patients. The degree of impairment of hepatic functions attributable to coexisting liver cirrhosis and the number of tumors in the liver significantly affected patient survival. For 50 patients having least impaired hepatic functions and a solitary tumor, the survival rate at 5 years was 53.5%. The patients had very few acute reactions to treatments and a few late sequelae during and after the treatments. CONCLUSIONS: Proton beam therapy for patients with HCC is effective, safe, well tolerable, and repeatable. It is the useful treatment mode for either cure or palliation for patients with HCC irrespective of tumor size, tumor location in the liver, insufficient feeding of the tumor with arteries, presence of vascular invasion, impaired hepatic functions, and coexisting intercurrent diseases.  相似文献   
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