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101.
Chlorpyrifos-methyl (CPM), an organophosphate insecticide, widely used for grain storage and agriculture, has been suspected as endocrine disrupter by a few in vitro studies. This study was performed to investigate the (anti-) estrogenicity and (anti-) androgenicity of CPM in vivo using immature rat uterotrophic assay and rat Hershberger assay. CPM with or without 17beta-estradiol were administered to 20 days old female rats to investigate its (anti-) estrogenic activity. Uterine and vaginal weight, uterine epithelial cell height were not affected by the treatment of CPM (2, 10, 50, 250 mg/kg). CPM 250 mg/kg potentiated relative vagina weight in 17beta-estradiol treated immature female rats without any changing of uterine weight. Relative liver weight was increased with decrease of body weight by CPM 250 mg/kg treatment. Uterine cell proliferation tested with bromodeoxyuridine labeling index was not observed in CPM treated rats. CPM with or without testosterone propionate were administered to castrated rat of 51 days old for 10 days to investigate the (anti-)androgenic activity,. The weight of relative and absolute androgen-dependent accessory sex organs; seminal vesicle with coagulating glands (SV/CG), ventral prostate gland (VP), glans penis (GP), levator ani plus bulbocarvernosus muscle (LABC) and Cowper's gland (CG,) were unchanged by the treatment of CPM alone. While CPM induced the increase of relative adrenal gland weight, CPM 50mg/kg decreased the weights of CV/CG, VP, CG and LABC without change of GP without changing of GP when it was treated with TP. In conclusion, CPM dose not show estrogenic and anti-estrogenic activity in immature female rats, but it represents anti-androgenic activity by inhibition of the TP-stimulated increase of the weight of accessory sex organs. 相似文献
102.
Simultaneous determination of ginsenoside Rb(1) and Rg(1) in human plasma by liquid chromatography-mass spectrometry 总被引:1,自引:0,他引:1
Ji HY Lee HW Kim HK Kim HH Chang SG Sohn DH Kim J Lee HS 《Journal of pharmaceutical and biomedical analysis》2004,35(1):207-212
A liquid chromatographic-mass spectrometric (LC/MS) method for the simultaneous determination of ginsenoside Rb(1) and Rg(1) in human plasma was developed. The method involved the protein precipitation followed by analysis of ginsenoside Rb(1) and Rg(1) in an Atlantis C(18) column with the gradient elution of acetonitrile and ammonium formate (10mM, pH 3.0) at a flow rate of 0.2 ml/min. The analytes were determined using electrospray negative ionization mass spectrometry in the selected ion monitoring mode. The standard curves for ginsenoside Rb(1) and Rg(1) were linear over the concentration range of 10.0-1000 ng/ml. The lower limit of quantification was 10.0 ng/ml using 100 microl plasma sample. The coefficient of variation of intra- and inter-day assays for ginsenoside Rb(1) and Rg(1) at three quality control levels ranged from 1.0 to 6.8% and 5.4 to 9.8%, respectively. Ginsenoside Rb(1) and Rg(1) were stable in blank human plasma at room temperature for 24h and following three freeze-thaw cycles. 相似文献
103.
Choi SJ Choi BK Kim HJ Lee SH Choi SH Park SJ Goo HW Lee JS Yoon CH 《Pediatric radiology》2002,32(3):179-182
OBJECTIVE: To evaluate the effectiveness of lateral decubitus high-resolution CT (HRCT) in detecting air trapping in children. MATERIALS AND METHODS: HRCT scans of 21 children with heterogeneous lung attenuation caused by air trapping (n = 10) or with infiltrative lung disease (n = 11) were reviewed retrospectively. The air-trapping disease included bronchiolitis obliterans (n = 7), bronchial obstruction due to mediastinal lymphoma (n = 1), endobronchial haemangioma (n = 1) and foreign body aspiration (n = 1). HRCT was performed in both lateral decubitus positions as well as the supine position. The attenuation (Hounsfield units; HU) was measured in both the hypo- and adjacent hyper-attenuating areas of the heterogeneous lung portion, and the difference of attenuation between these two areas was calculated in the supine and both lateral decubitus scans, respectively. The attenuation differences of the three scans were compared in each group. RESULTS: The attenuation difference was larger in the ipsilateral decubitus (207.95 +/- 105.24 HU) scans than in the contralateral (121.25 +/- 90.05 HU) or supine (162 +/- 94.01 HU) scans in the air-trapping group (P < 0.05). There were no significant differences among the three scans in the infiltrative lung disease group (P > 0.05). CONCLUSIONS: Lateral decubitus HRCT is an effective adjunct to standard HRCT in the evaluation of air trapping as a cause of mosaic lung attenuation in uncooperative paediatric patients. 相似文献
104.
Rapid and irreversible cystic change of pulmonary tuberculosis in an immunocompetent adult 总被引:1,自引:0,他引:1
This case report illustrates rapid and irreversible cystic change associated with disseminated pulmonary tuberculosis in an immunocompetent adult. In this patient, cystic lesions persisted after successful treatment of Mycobacterium tuberculosis and resulted in spontaneous pneumothorax with persistent air leak. 相似文献
105.
Shin HY Yun YB Kim JY Moon G Shin TY Kim HS Kim HM 《Immunopharmacology and immunotoxicology》2002,24(4):583-594
Dodutang has been used for treatment of various allergic inflammation diseases in Korea. However, it is still unclear how Dodutang prevents these diseases in experimental animal models. Mast cells play an important roles in allergic and other inflammatory reactions by producing a spectrum of powerful mediators including preformed and de novo synthesized cytokines. In this study, we investigated the effect of Dodutang on mast cell-mediated allergic and inflammatory reactions. Dodutang (0.001-5 g/L) significantly inhibited the histamine release from rat peritoneal mast cells activated by compound 48/80. Dodutang (0.001-5 g/kg) dose-dependantly inhibited the passive cutaneous anaphylaxis reaction activated by anti-dinitrophenyl (DNP) IgE in a rat model, especially, by 78.96% at the concentration of 5 g/kg. In addition, Dodutang potently inhibited the secretion of tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta in phorbol 12-myristate 13-acetate plus calcium ionophore A23187-stimulated human mast cells. However, IL-6 secretion was enhanced at the same conditions. Dodutang also inhibited the main inflammatory cytokine TNF-alpha protein expression in human mast cells. These results provide evidences that Dodutang may be beneficial in the treatment of acute and chronic allergic diseases. 相似文献
106.
Seo JB Im JG Goo JM Chung MJ Moon WK Lee KH Kim IO 《Acta radiologica (Stockholm, Sweden : 1987)》2003,44(4):403-410
Purpose:
To compare contrast-enhanced CT angiography (CTA) and gadolinium-enhanced MR angiography (MRA) for the detection of subsegmental-sized pulmonary emboli in a pig model. Material and Methods:
In 5 anesthetized pigs, 3-mm diameter embolic materials made of Konjac, a semisolid food, were introduced through the internal jugular vein into pulmonary arteries. After embolization, CTA and MRA images were obtained. Respiration was suspended during CTA and MRA image acquisition. Two readers reviewed the CTA and MRA images to detect emboli. The pigs were sacrificed, and sliced specimens of inflated lung served as the gold standard. Results:
Thirty-six emboli were detected within peripheral arteries. The sensitivity (and 95% confidence intervals) of CTA for the two readers were 57% (39-74%) and 66% (48-81%), and 88% (69-98%) and 92% (74-94%) for MRA. The specificity of CTA was 95% (91-97%) and 98% (96-99%), and that of MRA was 85% (74-93%) and 90% (80-96%). Interobserver agreement was higher for MRA (kappa 0.898) than CTA (kappa 0.574). Conclusion:
For the detection of subsegmental pulmonary emboli, MRA was superior to CTA, with a higher sensitivity and interobserver agreement by demonstrating perfusion deficits. 相似文献
To compare contrast-enhanced CT angiography (CTA) and gadolinium-enhanced MR angiography (MRA) for the detection of subsegmental-sized pulmonary emboli in a pig model. Material and Methods:
In 5 anesthetized pigs, 3-mm diameter embolic materials made of Konjac, a semisolid food, were introduced through the internal jugular vein into pulmonary arteries. After embolization, CTA and MRA images were obtained. Respiration was suspended during CTA and MRA image acquisition. Two readers reviewed the CTA and MRA images to detect emboli. The pigs were sacrificed, and sliced specimens of inflated lung served as the gold standard. Results:
Thirty-six emboli were detected within peripheral arteries. The sensitivity (and 95% confidence intervals) of CTA for the two readers were 57% (39-74%) and 66% (48-81%), and 88% (69-98%) and 92% (74-94%) for MRA. The specificity of CTA was 95% (91-97%) and 98% (96-99%), and that of MRA was 85% (74-93%) and 90% (80-96%). Interobserver agreement was higher for MRA (kappa 0.898) than CTA (kappa 0.574). Conclusion:
For the detection of subsegmental pulmonary emboli, MRA was superior to CTA, with a higher sensitivity and interobserver agreement by demonstrating perfusion deficits. 相似文献
107.
The biological assessments of the flora and fauna in the near-shore ocean environment, specifically Barbers Point Harbor (BPH), demonstrate the usefulness of these biological analyses for evaluation of the changes occurring following man-made excavation for expansion of the harbor. The study included identification and enumeration of macroalgae and dinoflagellates and analyses of herbivores and carnivores in four areas within the perimeter of the harbor and the north and south entrances into the harbor. Numbers of macroalgae varied between 1994 and 1999 surveys, with significant decrease in numbers in stations C, D and E. Stations A and B were similar between 1994 and 1999 with a slight increase in 1999. The significant differences were shown with the appearance of Gambierdiscus toxicus (G toxicus) in 1999 among the algae in stations A and B. Assessment of herbivores and carnivores with the immunological membrane immunobead assay using monoclonal antibody to ciguatoxin and related polyethers demonstrated an increase in fish toxicity among the herbivore from 1994-1999 (22% increase) with a decrease (22%) in non-toxic fish. This was also demonstrated in the carnivores, but to a lesser degree. It is suggested that the biological analyses of the flora and the fauna of the near-shore ocean environment are appropriate to assess the changes that occur from natural and man-made alterations. 相似文献
108.
Sang Baek Ryu Jang Hee Ye Jong Seung Lee Yong Sook Goo Chi Hyun Kim Kyung Hwan Kim 《The Korean journal of physiology & pharmacology》2009,13(6):443-448
For successful visual perception by visual prosthesis using electrical stimulation, it is essential to develop an effective stimulation strategy based on understanding of retinal ganglion cell (RGC) responses to electrical stimulation. We studied RGC responses to repetitive electrical stimulation pulses to develop a stimulation strategy using stimulation pulse frequency modulation. Retinal patches of photoreceptor-degenerated retinas from rd1 mice were attached to a planar multi-electrode array (MEA) and RGC spike trains responding to electrical stimulation pulse trains with various pulse frequencies were observed. RGC responses were strongly dependent on inter-pulse interval when it was varied from 500 to 10 ms. Although the evoked spikes were suppressed with increasing pulse rate, the number of evoked spikes were >60% of the maximal responses when the inter-pulse intervals exceeded 100 ms. Based on this, we investigated the modulation of evoked RGC firing rates while increasing the pulse frequency from 1 to 10 pulses per second (or Hz) to deduce the optimal pulse frequency range for modulation of RGC response strength. RGC response strength monotonically and linearly increased within the stimulation frequency of 1~9 Hz. The results suggest that the evoked neural activities of RGCs in degenerated retina can be reliably controlled by pulse frequency modulation, and may be used as a stimulation strategy for visual neural prosthesis. 相似文献
109.
Jung-Sup Lee Yong-Sook Park Jeong-Taik Kwon Jong-Sik Suk 《Journal of Korean Neurosurgical Society》2010,47(5):395-398
The majority of cases of pneumocephalus are secondary to trauma or medical intervention. Spontaneous, non-traumatic pneumocephalus is an uncommon condition. Most cases of spontaneous pneumocephalus require surgery. However, if there is no evidence of infection or cerebrospinal fluid leak, bed rest and follow-up imaging is an alternative treatment. Herein, we report a 31-year-old man with spontaneous pneumocephalus associated with pneumosinus dilatans. 相似文献
110.
Jae Hyung Park M.D. Goo Lee Joon Koo Han Sang Joon Kim Myoung Mook Lee 《Cardiovascular and interventional radiology》1990,13(6):351-353
Inadvertent embolic obstruction of the distal abdominal aorta and left renal artery during a percutaneous mitral valvuloplasty
procedure in a patient with mitral stenosis is reported. The embolism was from a left atrial thrombus which was detected by
magnetic resonance imaging (MRI) but not by transesophageal echocardiography. 相似文献