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131.
In search of natural extracts for hair growth, we found that the extract of dried root of Sophora flavescens has outstanding hair growth promoting effect. After topical application of Sophora flavescens extract onto the back of C57BL/6 mice, the earlier conversion of telogen-to-anagen was induced. The growth of dermal papilla cells cultured in vitro, however, was not affected by Sophora flavescens extract treatment. RT-PCR analysis showed that Sophora flavescens extract induced mRNA levels of growth factors such as IGF-1 and KGF in dermal papilla cells, suggesting that the effects of Sophora flavescens extract on hair growth may be mediated through the regulation of growth factors in dermal papilla cells. In addition, the Sophora flavescens extract revealed to possess potent inhibitory effect on the type II 5alpha-reductase activity. Taken together, these results suggest that Sophora flavescens extract has hair growth promoting potential and can be used for hair growing products.  相似文献   
132.
Significance of acute multiple brain infarction on diffusion-weighted imaging   总被引:39,自引:0,他引:39  
BACKGROUND AND PURPOSE: Diffusion-weighted imaging (DWI) is superior to conventional MRI in identification of small new ischemic lesions and discrimination of recent infarcts from old ones. Thus, this technique is useful in the detection of acute multiple brain infarcts (AMBI). We sought to determine the frequency and the topographical and etiologic patterns of AMBI detected on DWI. METHODS: We studied 329 consecutive ischemic stroke patients who underwent DWI and MRI/MR angiography within 4 days of stroke onset. AMBI was defined as noncontiguous high signal intensities on DWI in >1 vascular territory. Stroke mechanism was determined according to the criteria of the Trial of Org 10172 in Acute Stroke Treatment (TOAST). RESULTS: We detected AMBI in 95 patients (28.9%). AMBI in anterior circulation was found in 62 cases: in 1 hemisphere in 42 (group A) and in bilateral hemispheres in 20 (group B). Twenty-two patients had AMBI in the posterior circulation (group C) and 11 in both anterior and posterior circulations (group D). The most frequent cause of stroke was large-artery atherosclerosis in groups A (33/42), B (9/20), and C (15/22) (P=0.02) and cardioembolism in group D (6/11) (P=0.02). Elevated fibrinogen or hematocrit was significantly associated with group B (P=0.01). In 9 patients in groups B and D, anatomic variations of anterior or posterior cerebral arteries or patent posterior communicating artery contributed to AMBI. CONCLUSIONS: Different topographical patterns of AMBI are associated with different vascular pathologies and stroke mechanisms. Hemorheologic abnormality or vascular anatomic variations may be contributing factors in the pathogenesis of AMBI in bilateral cerebral hemispheres or in both anterior and posterior circulations.  相似文献   
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Background: This retrospective study was performed to assess the outcome among patients who underwent hepatic resection or tumor ablation after hepatic artery infusion (HAI) therapy downstaged previously unresectable hepatocellular carcinoma (HCC) or liver metastases from colorectal cancer (CRC).Methods: Between 1983 and 1998, 25 patients with HCC and 383 patients with hepatic CRC metastases were treated with HAI therapy for unresectable liver disease. We retrospectively reviewed the records of 26 (6%) of these patients who underwent subsequent surgical exploration for tumor resection or ablation.Results: At a median of 9 months (range 7–12 months) after HAI treatment, four patients (16%) with HCC underwent exploratory surgery; two underwent resection with negative margins, and the other two were given radiofrequency ablation (RFA) because of underlying cirrhosis. At a median postoperative follow-up of 16 months (range 6–48 months), all four patients were alive with no evidence of disease. At a median of 14.5 months (range 8–24 months) after HAI therapy, 22 patients with hepatic CRC metastases underwent exploratory surgery; 10 underwent resection, 6 underwent resection and RFA or cryotherapy, and 2 underwent RFA only. At a median follow-up of 17 months, 15 (83%) of the 18 patients with CRC who had received surgical treatment had developed recurrent disease; the other 3 died of other causes (1 of postoperative complications) within 7 months of the surgery. One patient in whom disease recurred underwent a second resection and was disease-free at 1 year follow-up.Conclusions: Hepatic resection or ablation after tumor downstaging with HAI therapy is a viable option for patients with unresectable HCC. However, given the high rate of recurrence of metastases from CRC, hepatic resection or ablation after downstaging with HAI should be used with caution.Presented at the 53rd Annual Meeting of the Society of Surgical Oncology, New Orleans, Louisiana, March 16–19, 2000.  相似文献   
135.
BACKGROUND: Restricted sensory deficits along the somatotopic topography of the medial lemniscus rarely develop in medial medullary infarction. We describe a patient with medial medullary infarction who presented with dermatomal sensory deficits caused by a medial lemniscal lesion. CASE DESCRIPTION: A 58-year-old man presented with sudden right-sided hemiparesis and paresthesia. He had noticed the paresthesia below the level of the right L5 dermatome, where his vibration and position senses were mildly diminished. His paresthesia was more severe over the right calf and foot. Magnetic resonance images of the brain showed an acute small infarct in the medial-ventral portion of the left rostral medulla oblongata. A nerve conduction study and electromyography showed no abnormalities. At follow-up, the patient's motor and sensory deficits had improved considerably. CONCLUSIONS: The patient showed lemniscal sensory deficits below the right L5 dermatome that were caused by the partial involvement of the medial lemniscus. These findings suggest that lemniscal sensory dermatomal representation is preserved at least up to the level of the medulla oblongata.  相似文献   
136.
A matched-control study comparing standard radiotherapy versus neoadjuvant chemotherapy and radiation was undertaken to clarify the effects of neoadjuvant systemic chemotherapy for locally advanced squamous cell carcinoma of the maxillary antrum. Thirty-four patients with inoperable maxillary cancer were treated with neoadjuvant chemotherapy and radiotherapy (Group II). Before starting radiotherapy, all patients in Group II received two or three cycles of neoadjuvant chemotherapy consisting of cisplatin and a 5-day continuous infusion of 5-fluorouracil with or without intravenous injection of vinblastine. Radiation doses ranged from 66 Gy to 75 Gy (median, 70 Gy). The response rate, patterns of failure, toxicity, and survival for Group II were compared with those for 34 stage-matched patients treated with radiation alone (Group I). Despite a higher response rate to neoadjuvant chemotherapy, the recurrence rate and patterns of treatment failure were not influenced by the addition of neoadjuvant chemotherapy. In most cases, neoadjuvant chemotherapy did not interfere with subsequent radiotherapy, and radiation-induced late complications occurred equally in both treatment groups. After a median follow-up of 48 months, there was no significant difference in 5-year actuarial survival or disease-free survival between the two treatment groups. Radiation alone for inoperable maxillary cancer was clearly suboptimal for improving local control and survival rate, but neoadjuvant chemotherapy in addition to standard radiotherapy failed to demonstrate any therapeutic advantage over radiation alone.  相似文献   
137.
Song JJ  Kim JH  Lee H  Kim E  Kim J  Park YS  Ahn J  Yoo NC  Roh JK  Kim BS 《Oncology reports》2000,7(1):119-124
Retroviral vectors have recently experienced limited use in cancer gene therapy mainly due to poor transduction efficiency. To overcome this drawback, we attempted to enhance the transduction efficiency by employing different retroviral packaging cell lines and chemical additives. The retrovirus from the PG13 packaging cell line gave mostly higher or similar transduction efficiencies in a variety of human cancer cell lines compared to the retrovirus from the PA317, Bing, or FLYRD18 packaging cell line. A cationic liposome, especially Lipofectamine, significantly enhanced the transduction efficiency of a retrovirus. However, the retrovirus derived from the PG13 cell line could not infect the murine cell line efficiently even after Lipofectamine treatment. Furthermore, chloroquine did not improve the transduction efficiency regardless of the presence of chemical additives. These results, therefore, suggested that the transduction efficiency of a retrovirus in human cancer cells can certainly be improved when a proper packaging cell line is chosen. In addition, this study implied that Lipofectamine is a superb additive to enhance the transduction efficiency of a retrovirus via a specific virus envelope protein-receptor interaction for virus entry, and that receptor-mediated endocytosis does not seem to be the leading route of virus delivery to liberate a virus genome.  相似文献   
138.
Many articles have been written on the correction of syndactyly, most of which refer to the fingers. The use of skin grafts appears necessary to obtain satisfactory correction in much of the literature. The authors present a case of desyndactyly without using a skin graft.  相似文献   
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