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21.
Hernández AF Gonzalvo MC Gil F Villanueva E Pla A 《Environmental toxicology and pharmacology》1997,3(1):83-86
The effects of three different enzyme-inducing agents (phenobarbital, 3-methylcholanthrene and rifampicin) on plasma and liver microsomal fraction paraoxonase and arylesterase were studied in rats. Although phenobarbital and 3-methylcholanthrene each increased the esterase activities in microsomal fraction, only 3-methylcholanthrene was capable to increase them in plasma. By contrast, the administration of rifampicin decreased both enzyme activities in liver and plasma. The results indicate that at least there exists two esterase activities in rat liver microsomes which hydrolyse both paraoxon and phenylacetate, but only one of them is released into the blood. 相似文献
22.
El-Harazi SM Feldman RM Villanueva G Carter-Dawson L Mietz H Chuang AZ 《Journal of glaucoma》1999,8(6):374-379
PURPOSE: Mitomycin C (MMC) is commonly administered during filtering surgery to enhance the success of the procedure. Unfortunately, the increased success rate is associated with complications, including late bleb leaks, endophthalmitis, and ciliary epithelial toxicity. The purpose of this study was to investigate a safe and effective dose regimen for MMC to reduce incidence of those complications. METHODS: Trabeculectomy was performed in 36 rabbits. MMC was applied only during surgery, only one day after surgery, or once daily after surgery for 3 days at lower concentrations. Balanced salt solution (BSS) was administered during surgery to one group as a placebo. The time to bleb failure was determined and the eyes were evaluated histopathologically. Success and toxicity were compared for the different treatment groups. RESULTS: The mean time until trabeculectomy failure was 2.83 days for the placebo group, 6.33 days with administration of MMC 0.5 mg/mL during surgery, 7.83 days with administration of MMC 0.5 mg/mL once after surgery, and 11, 9, and 4.83 days with administration of MMC 0.1 mg/mL, 0.05 mg/mL, or 0.025 mg/mL, respectively, once a day for 3 consecutive days. On electron microscopic examination of the ciliary epithelium, toxic effects were greatest with MMC concentrations of 0.5 mg/mL and were less with lower concentrations. CONCLUSION: The effect of MMC on trabeculectomy survival was dependent on both the concentration and the method of administration. Lower concentrations with multiple postoperative administrations were as effective as but caused less ciliary body toxicity than intraoperative administration of higher concentrations. 相似文献
23.
Carrigg SY Hillemeyer LE Villanueva EE 《The Journal of orthopaedic and sports physical therapy》1992,16(1):19-24
Several previous studies have shown that intervertebral discs compress under the forces of axial loading, but few thus far have examined the effect of disc compression on the mobility of the spine. The purpose of this study was to determine if decreases in disc height and the mobility of the vertebral column between T7 and S2 in young, healthy males occurred after running and if there was a positive correlation between these two variables. The population of interest consisted of 30 18- to 25-year-old healthy males who ran 10-70 miles per week, all of whom had no previous or current back pathology. Following an 8-minute warm-up on a Fitron bicycle, vertebral column height (from C7 to S2) and vertebral column lateral flexion to the left (from T7 to S2) were measured. Directly following measurement, each subject ran 7 miles on a predetermined flat, paved course at a comfortable pace. Immediately following the run, each subject was measured again for vertebral column height and lateral flexion to the left. Paired t-tests revealed significant decreases in both vertebral column height and left lateral flexion. Pearson's r revealed only a small correlation between the decreases in these two variables. Although the correlation was not significant, the decreases in both variables may have implications for physical therapy with respect to range of motion measurements, because range of motion may change with varied amounts of disc compression, and for exercise programs for patients with various back pathologies, because certain back pathologies may be influenced by the degree of disc compression. J Orthop Sports Phys Ther 1992;16(1):19-24. 相似文献
24.
目的观察小分割分次立体定向放射治疗(fractionated stereotatic radiation therapy,FSRT)脑转移瘤的近期疗效.方法15例病人单纯全脑外照射(WBRT组),中间平面剂量20~40Gy/10~20次/2~4周.17例病人接受FSRT(FSRT组),每次分次剂量为2.5~3.0Gy.其中11病人行单纯FSRT,中心总剂量为30~60Gy/1 0~20次/2~4周;6例病人先行WBRT,然后行FSRT,中心总剂量为46~60Gy/5~6周.结果KSP评分增加10分以上者,WBRT组为5 3.3%,FSRT组为82.4%.(P<0.05).WBRT组有效率(CR PR)为50.0%;FSRT组有效率(CR PR)为80.0%.中位生存率:WBRT组为3.5月,FSRT组为10.0月.结论FSRT能有效地控制脑转移瘤,减轻神经系统症状,提高生存质量,延长病人生存期,而没有增加副作用,值得临床推广应用. 相似文献
25.
de Diego Rodríguez E Roca Edreira A Martín García B Hernández Rodríguez R Portillo Martín JA Gutiérrez Baños JL Correas Gómez MA del Valle Schaan JI Villanueva Peña A Rado Velázquez MA Torío Sánchez B 《Actas urologicas espa?olas》2000,24(8):685-688
The schwannoma is a tumor resulting from the Schwann cells of neural shwath, being its retroperitoneal localization quite unusual. This tumor is clinically unspecified and in most of the cases it originates symptoms coming from the compression of the close structures when its localization is retroperitoneal. Its diagnosis is quite often fortuitous being confirmed by anatomopathological study afterwards. The treatment is surgical radical exeresis with subsequent followup. We report a new case of this uncommon retroperitoneal pathology in a female patient showing a nonspecific clinic. Two years after the surgery she remains asymptomatic without any radiological evidence of recidive. 相似文献
26.
de Diego Rodríguez E del Valle Schaan JI Gutiérrez Baños JL Martín García B Hernández Rodríguez R Portillo Martín JA Correas Gómez MA Roca Edreira A Villanueva Peña A Rado Velázquez MA Hernández Rodríguez A 《Actas urologicas espa?olas》2000,24(10):836-839
Prostatic carcinoma may be diagnosed by the clinic manifestations or by the symptoms for locoregional disemination and distance metastasis. The lymphatic system is the first metastatic station, which is affected in a high percentage of cases. Event it may simulate lymphoproliferatives process and it si uncommon the lymphatic macroaffectation at first. In theses cases, the histologic and immunohistochemical study by the determination of prostatic specific antigen in lymph nodes can provice the diagnosis. Treatment of these tumors is palliative with hormonotherapy. Prognosis is bad with a low survival at five years. 相似文献
27.
We compared the tumor-initiating activities toward mouse skin of two
structurally related polycyclic aromatic hydrocarbon diol epoxides: racemic
anti-1,2,3,4-tetrahydro-5,6-dimethylchrysene-1,2-diol-3,4- epoxide
(5,6-diMeCDE) and racemic anti-1,2,3,4-tetrahydro-5-
methylchrysene-1,2-diol-3,4-epoxide (5-MeCDE). Tumors induced by these diol
epoxides were analysed for mutations in the Ha-ras gene. 5,6- diMeCDE is
derived from the non-planar parent compound 5,6- dimethylchrysene, and
reacts to approximately equal extents with dA and dG in DNA, whereas
5-MeCDE is derived from a nearly planar parent compound, 5-methylchrysene,
and reacts mainly with dG in DNA. 5,6- diMeCDE, at initiating doses of 33,
100 or 400 nmol per mouse, induced 1.2, 2.2 and 6.2 skin tumors per mouse,
respectively. It was significantly less tumorigenic than 5-MeCDE which
induced 3.1, 7.5 and 9.1 skin tumors per mouse at the same doses. Tumors
induced by 5,6- diMeCDE had a large number of CAA-->CTA mutations in
codon 61 of the Ha- ras gene: 50, 55 and 75% of the tumors analysed had
this mutation at the 33, 100 and 400 nmol doses. No mutations were found in
codons 12 and 13 in the tumors induced by 5,6-diMeCDE. In contrast,
CAA-->CTA mutations in codon 61 were rarely seen in tumors induced by
5-MeCDE. At the highest dose of 5-MeCDE, 20% of the tumors analysed had
mutations at G of codons 12 and 13. The results of this comparative study
support the hypothesis that mutations in the Ha-ras gene in mouse skin
tumors induced by PAH diol epoxides occur as a result of their direct
reaction with the gene. However, pathways other than the commonly observed
Ha- ras codon 61 mutations are clearly important in mouse skin
tumorigenesis by these diol epoxides.
相似文献
28.
Denervation of the synergists of the medial gastrocnemius (MG) muscle in the cat hind leg results in a progressive increase in the magnitude of burst activity in the MG muscle during walking. The increase in burst magnitude is associated with an increase in the slope of the relationship between the magnitude of individual MG bursts and the amplitude of ankle flexion during stance. This finding is consistent with the hypothesis that the increase in MG burst magnitude is due to an increase in gain of reflex pathways reinforcing the activation of MG. The increase in slope is use-dependent since it was not observed when the leg was released from a cast that immobilized the leg for 6 days. 相似文献
29.