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181.
T Kanno H Oka K Kim A Tamori K Ohtake H Sakaguchi N Kurioka T Kuroki Y Mizoguchi K Kobayashi 《Nihon Shokakibyo Gakkai zasshi》1992,89(1):55-60
To evaluate prognostic significance of echogenic lesion within small hepatocellular carcinoma (SHCC, less than or equal to 2 cm in diameter), clinical and pathological findings of 32 cases with SHCC containing echogenic lesion (echogenic SHCC) were compared with those of 55 cases with non-echogenic SHCC. Compared with the non-echogenic SHCC group, the frequency of clinical stage I was significantly higher, and there were significantly more cases with solitary tumor relative to cases with multiple tumors in the echogenic SHCC group. Histologically, the incidence of the HCC composed of well-differentiated tumor cells corresponding to Edmondson's grade I was significantly higher in the echogenic SHCC group than in the non-echogenic SHCC group. Although HCCs tended to become progressively less differentiated with increasing tumor sizes in the both groups, the process of cellular change appeared to proceed more slowly in the echogenic SHCC group. Survival rate after tumor detection was 73% at three years, 56% at five years and 48% at seven years and nine years in the echogenic SHCC group, while it was 46% at three years, 42% at five years and 0% at seven years in the non-echogenic SHCC group. The present results showed that the presence of echogenic lesion within SHCC could be useful prognostic indicator. 相似文献
182.
A 1.5-year-old male Belgian Malinosis Military Working Dog presented with a 1-month history of intermittent hematuria. Diagnostic ultrasound and contrast radiography demonstrated large blood clots in the urinary bladder and a filling defect in the right renal pelvis. At surgery, clotted blood was present in the right ureter and bladder. Following right nephrectomy, the dog returned to training. One month later, elevations in urea nitrogen and creatinine were noted. Hematuria recurred at 3 months and the dog was found dead in its kennel. Necropsy showed a blood-filled left renal pelvis and ureter. 相似文献
183.
E Jung H-S Won S-K Kim J-Y Shim P R Lee A Kim J K Kim 《Ultrasound in obstetrics & gynecology》2006,27(5):562-565
Fetal thrombosis of the dural sinus is an extremely rare congenital cerebrovascular condition that is potentially fatal. We report a case of dural sinus thrombosis diagnosed by prenatal ultrasonography and fetal magnetic resonance imaging (MRI) in the second trimester. The thrombosis showed partial resolution during pregnancy and resolved spontaneously after birth without neurological complications. This is the first report of spontaneous postnatal resolution, and may provide helpful information on the natural history and prenatal counseling of fetal thrombosis of the dural sinus. 相似文献
184.
Soo Jeong Lim Jin Chul Paeng Sung Jin Kim Sang Yoon Kim Heuiran Lee Dae Hyuk Moon 《Journal of nuclear medicine》2007,48(3):398-404
Increased expression of the sodium iodide symporter (NIS) is required for effective radioiodine treatment and reporter gene imaging of breast cancer. We investigated the effect of retinoic acid on adenovirus-mediated expression of the human NIS gene in the MCF-7 breast cancer cell line. METHODS: The MCF-7 cell line was infected with recombinant adenovirus carrying the human NIS gene (Rad-NIS). Levels of NIS messenger RNA (mRNA) and protein expression and radioiodine ((125)I) uptake were measured to evaluate adenovirus-mediated NIS gene expression in wild-type and Rad-NIS-infected MCF-7 cells after treatment with all-trans-retinoic acid (ATRA; 10(-8)-10(-6) mol/L). RESULTS: The transduction efficiency of adenovirus in MCF-7 cells at a multiplicity of infection (MOI) of 50 was >60%. After incubation with 10(-6) mol/L ATRA, the mRNA level in Rad-NIS-infected MCF-7 cells increased to 118.5 times that of wild-type MCF-7 cells, whereas the mRNA level in wild-type MCF-7 cells showed only a 2.1-fold increase. Western blot, immunocytochemical staining, and flow cytometry analyses showed that NIS protein expression in MCF-7 cells infected with Rad-NIS increased after ATRA treatment. With ATRA treatment, the amount of (125)I uptake increased in a dose-dependent manner (P < 0.001). The (125)I uptake in wild-type MCF-7 cells increased 3.1-, 5.5-, and 7.6-fold with treatment with 10(-8), 10(-7), and 10(-6) mol/L ATRA, respectively. Rad-NIS-infected cells showed a 4.0-fold increase in (125)I uptake. Treatment of Rad-NIS-infected cells with 10(-8), 10(-7), and 10(-6) mol/L ATRA increased (125)I uptake by 4.9-, 8.2-, and 27.6-fold, respectively, compared with wild-type MCF-7 cells. The level of NIS expression in Rad-NIS-infected MCF-7 cells treated with 10(-6) mol/L ATRA (245.0 +/- 13.7 pmol/10(6) cells) was much greater than the sum of the expression levels seen in ATRA-treated wild-type cells and Rad-NIS-infected wild-type cells. CONCLUSION: Retinoic acid increases adenovirus-mediated NIS expression in MCF-7 cells. Our results indicate that improved efficiency of NIS gene therapy or reporter imaging in breast cancer may be possible with retinoic acid treatment. 相似文献
185.
Jungsun Park MD PhD Naomi Hisanaga MD Yangho Kim MD MPH 《American journal of industrial medicine》2009,52(8):625-632
Many corporations move their manufacturing facilities or technologies from developed to developing countries. Stringent regulations have made it costly for industries to operate in developed, industrialized countries. In addition, labor costs are high in these countries, and there is increasing awareness among the general public of the health risks associated with industry. The relocation of hazardous industries to developing countries is driven by economic considerations: high unemployment, a cheaper labor force, lack of regulation, and poor enforcement of any existing regulations make certain countries attractive to business. The transfer of certain industries from Japan to Korea has also brought both documented occupational diseases and a new occupational disease caused by chemicals without established toxicities. Typical examples of documented occupational diseases are carbon disulfide poisoning in the rayon manufacturing industry, bladder cancer in the benzidine industry, and mesothelioma in the asbestos industry. A new occupational disease due to a chemical without established toxicities is 2‐bromopropane poisoning. These examples suggest that counter‐measures are needed to prevent the transfer of occupational health problems from a developed to a developing country. Corporate social responsibility should be emphasized, close inter‐governmental collaboration is necessary and cooperation among non‐governmental organizations is helpful. Am. J. Ind. Med. 52:625–632, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
186.
R. Parker Ward MD Mouaz H. Al-Mallah MD Gabriel B. Grossman MD PhD Christopher L. Hansen MD Robert C. Hendel MD Todd C. Kerwin MD Benjamin D. McCallister Jr MD Rupa Mehta MD Donna M. Polk MD MPH Peter L. Tilkemeier MD Aseem Vashist MD Kim Allan Williams MD David G. Wolinsky MD Edward P. Ficaro PhD 《Journal of nuclear cardiology》2007,14(6):911-e38
187.
188.
Jun-Seok Lee Byung-Hwan Yang Jang-Han Lee Jun-Ho Choi Ihn-Geun Choi Sae-Byul Kim 《Clinical neurophysiology》2007,118(11):2489-2496
OBJECTIVE: Recent findings have demonstrated that the EEG possesses long-range temporal (auto-) correlations (LRTC) in the dynamics of broad band oscillations. The analysis of LRTC provides a quantitative index of statistical dependencies in oscillations on different time scales. We analyzed LRTC in resting EEG signals in depressed outpatients and healthy controls. METHODS: The participants in this study were 11 non-depressed, age-matched controls, and 11 unmedicated unipolar depressed patients. EEG data were obtained from each participant during 5-min resting baseline periods with eyes closed and then analyzed with detrended fluctuation analysis (DFA), a scaling analysis method that quantifies a simple parameter to represent the correlation properties of a time series. The scaling exponent, the result of DFA, provides a quantitative measure of LRTC from the EEG. RESULTS: The present study demonstrates that all the scaling exponents in depressed patients and healthy controls were greater than 0.5 and less than 1.0, regardless of condition. Furthermore, the scaling exponents of depressed patients have relatively higher values in whole brain regions compared to healthy controls, with significant differences at F3, C3, T3, T4 and O1 channels (p<0.05). Finally, a significant linear correlation was observed between the severity of depression and the scaling exponent over most of the channels, except O2. CONCLUSIONS: These results suggest that the brain affected by a major depressive disorder shows slower decay of the LRTC, and that the persistence of the LRTC of EEG in depressed patients was associated with the severity of depression over most of the cortical areas. SIGNIFICANCE: The DFA method may broaden our understanding of the psychophysiological basis of depression. 相似文献
189.
Topical high-molecular-weight hyaluronan and a roofing barrier sheet equally inhibit postlaminectomy fibrosis. 总被引:9,自引:0,他引:9
Wayne H Akeson Jennifer B Massie Bill Huang Alexander Giurea Robert Sah Steven R Garfin Choll W Kim 《The spine journal》2005,5(2):180-190
BACKGROUND CONTEXT: The relevance of epidural fibrosis to failed back surgical outcomes remains controversial. Previous studies on the correlation between epidural fibrosis and clinical outcome after laminectomy are inconclusive, and clinical approaches applied to reduce postlaminectomy spinal canal scarring have produced mixed outcomes. PURPOSE: Improved preclinical models are required to address the fundamental question of the relationship between postlaminectomy fibrosis and chronic pain. This study is directed at establishing small animal postlaminectomy models characterized by significantly reduced scar within the spinal canal postoperatively. Such preclinical models are offered as a platform for future studies to explore the potential relationship between postlaminectomy epidural fibrosis and persistent neuropathy with its potential for altered spinal mechanisms for pain processing, so-called spinal facilitation. Such experiments could be constructed in these models for comparison of pain behavior and its underlying neurochemistry both in the presence and absence of extensive postlaminectomy epidural scar. STUDY DESIGN/SETTING: A modified rat laminectomy model was employed to assess epidural fibrosis using a quantitative biochemical collagen assessment approach along with correlative histology. This group served as the control for comparison with groups in which antifibrotic measures were employed. We compared antifibrotic efficacy of a bioabsorbable roofing barrier sheet placed over the laminectomy defect with topical high-molecular-weight hyaluronan (HMW HA) gel, each applied postoperatively to prevent proliferative epidural scarring. Routine biomechanical tensile strength testing was employed to assess wound-healing strength. METHODS: A bilateral laminectomy (L5 and L6) with associated unilateral disc injury (L5-L6) was performed in 98 male Harlan Sprague-Dawley rats. The laminectomy models described incorporated a unilateral disc injury at L5-L6 because herniated disc material has been shown to contribute proinflammatory cytokines in the postoperative wound. Five groups were employed for the study: 1) normal controls without surgery; 2) a laminectomy-disc injury group without treatment; 3) a laminectomy-disc injury group treated with topical HMW HA gel; 4) a laminectomy-disc injury group treated with 0.2-mm thick bioabsorbable roofing barrier sheet in which a protected space was maintained between overlying paraspinous muscles and the dura and 5) a 0.02-mm thin barrier sheet treatment group in which the sheet was placed directly on the dura. The animals were sacrificed at 3- and 8-week postoperative intervals for analysis. The dissected specimens were studied biochemically for hydroxyproline content to estimate total collagen within the canal and on the dura between L4 and L7. Additional specimens were prepared histologically and stained with Masson-Goldner Trichrome stain to confirm presence of proliferative collagen and to describe the presence or absence of wound-healing scar adherence to the dura. The surgical incisions were studied biomechanically by uniaxial tensile testing to determine ultimate force, strain and prefailure stiffness. Statistics were performed using analysis of variance. RESULTS: Gross appearance and histology studies showed that the untreated laminectomy group demonstrated postoperative scar formation that is adherent between the wound and the dorsum of the dura mater in both 3- and 8-week groups. Proliferative scar was substantially increased grossly between the 3- and 8-week intervals. By gross observation there was adherence of the L5 spinal nerve to the underlying disc and adjacent pedicle on the disc injury side. Gross observation of treatment groups, in contrast, disclosed that both the 0.2-mm thick roofing barrier sheet and topical HMW HA gel each prevented scar attachment to the dural sleeve at both the 3- and 8-week postoperative intervals. Furthermore, both the HMW HA gel and 0.2-mm thick roofing barrier sheet treatment groups had significant reduction of total collagen content in the laminectomy specimens measured biochemically at the two time periods compared with the untreated controls. Histologically, the HMW HA gel and the 0.2-mm thick barrier sheet findings were consistent with the gross observations concerning lack of adherence between scar of the overlying wound and the dura. Notably, both the 0.2- and the 0.02-mm barrier sheets became enveloped by a fibrotic envelope consistent with a foreign body reaction. In the group in which the 0.02-mm thin sheet was placed within the canal on top of the dura, there was an increase of fibrosis around the sheet within the canal leading to a space-occupying mass within the canal. Although the 0.2-mm thick roofing barrier placed external to the canal became enveloped by scar, it appeared to attract proliferative scar away from the epidural space, leaving the dura relatively free of scarring or adherence to overlying tissues. The mechanical properties of the incisional wound increased significantly between 3 and 8 weeks. The ultimate strength, stress, strain and stiffness of the several groups were similar at each time point. CONCLUSION: These results provide two preclinical rat laminectomy models of potential usefulness for the future study of the relevance of epidural fibrosis to behaviorally defined pain states, and for the study of the potential of an altered neurochemical signature in postlaminectomy pain conditions. Such preclinical models have become standard in studies of pain behavior and its neurochemistry in preclinical sciatic nerve and spinal nerve injury models, and should be of utility in the studies of postlaminectomy fibrosis. There was progressive scar proliferation and maturation in the untreated postlaminectomy group in the postoperative interval between 3 and 8 weeks. HMW HA gel applied topically and a 0.2-mm thick bioabsorbable Macropore sheet used as a roofing barrier each significantly reduced postlaminectomy proliferative scar without affecting the integrity of incisional wound healing. However, if the 0.02-mm thin barrier sheet used in this study is placed within the canal in contact with the dura and adjacent to the pedicles, the process of reabsorption results in a fibrotic mass within the canal. The preferred barrier sheet placement for this model is clearly in a roofing position bridging over the open epidural space. It must be placed in a manner to block off the paraspinous muscle healing response and still leave a gap between the sheet and the dura. 相似文献
190.
The embryonic gonads give rise to one of two morphologically and functionally different organs, a testis or an ovary. Sex determination is the embryonic process that determines the developmental fate of the gonad. In mammals, sex determination is regulated by a DNA binding protein encoded on the Y chromosome, Sry, and it's downstream mediator, Sox9, which trigger testis determination in the bipotential gonad. However, evidence suggests that the extracellular signals. Fgf9 and Wnt4, are also required to establish divergent organogenesis of the gonad. In this review, we discuss how these extracellular signals interface with cell-autonomous factors to determine the fate of the mammalian gonad, and we derive a model that could provide a molecular explanation for testis determination in vertebrates where Sry is absent. 相似文献