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991.
We performed an experimental study on slow releasing anticancer drug implantation treatment as a new therapy for hepatocellular carcinoma. Hydroxyapatite (HAP) was chosen for the carrier material and doxorubicin hydrochloride (DOX) for anticancer agent. DOX-HAP was produced by adsorbing DOX to porous HAP particles of 1375 +/- 125 microns diameter using the freeze drying method. In vitro experiments showed slow release of the drug resulting in the steady release of DOX from HAP for 1 month duration. In healthy white rabbits with DOX-HAP implantation in the liver, serum DOX was not detectable, and DOX release rate was stable at the implanted region after 7, 14, and 21 days. When DOX-HAP (DOX; 100 mg kg-1) was administered to mice with sarcoma 180, an improved survival rate was observed without acute toxicity. We also found that VX2 liver tumour growth on white rabbit was inhibited by implantation of DOX-HAP, without acute toxicity. We hope that DOX-HAP implantation therapy will open up new avenues for the treatment of hepatoma.  相似文献   
992.
We report a 50-year-old female with pulmonary metastases from breast cancer who responded to S-1. In September 2003, she underwent surgery for breast cancer. Four years 8 months after the operation, lung relapse was detected. After the treatment failure of FEC60 (5-FU 500 mg/m2, epirubicin 60 mg/m2, cyclophosphamide 500 mg/m2) and taxane antitumor drugs, oral administration of S-1 80 mg/body/day was initiated. At the end of three courses, thoracic CT revealed the disappearance of the lung metastasis. Advanced reactions during the administration period were mild. After 14 courses of S-1 therapy (during 11 months), a complete response was clinically maintained. S-1 showed a good antitumor effect and tolerance, and it might be useful for treating metastatic and recurrent breast cancers.  相似文献   
993.
994.
The antibacterial activity of compounds obtained from licorice was measured against upper airway respiratory tract bacteria such as Streptococcus pyogenes, Haemophilus influenzae and Moraxella catarrhalis. Among the tested compounds, licoricidin exhibited the highest activity against all tested microorganisms with an MIC of 12.5 microg/mL. Three coumarin derivatives, glycyrol, glycyrin and glycycoumarin also showed antibacterial activity.  相似文献   
995.
The C5a receptor (C5aR) expressed in various types of cancers is involved in C5a-induced cancer cell invasion. However, its role in gastric cancer has not yet been fully elucidated. Therefore, we studied the clinical significance of C5aR expression in gastric cancer. The association of C5aR expression in gastric cancer, determined by immunostaining using the anti-C5aR antibody, with clinicopathological parameters and outcomes was evaluated in 148 patients. Further, the association of C5aR expression in liver metastatic sites with clinicopathological parameters was investigated in a separate cohort of 58 patients who underwent hepatectomy. High tumoral C5aR expression (n = 45, 30.4 %) was significantly related to tumor location, cancer invasion depth, vascular and lymphatic invasion, and tumor stage. The 5-year recurrence-free and overall survival rates of patients with high tumoral C5aR expression were significantly lower than those of patients with low tumoral C5aR expression (50.9 vs. 84.2 %, P = 0.002 and 58.8 vs. 86.1 %, P = 0.007, respectively). The incidence of liver metastasis was significantly higher in patients with high tumoral C5aR expression (13.3 %) than in those with low tumoral C5aR expression (3.9 %; P = 0.04). C5aR expression at liver metastatic sites was associated with the C5aR expression status at the primary site (P = 0.0004), vascular invasion at the primary site (P = 0.04), and tumor size at the metastatic site (P = 0.01). C5aR expression in gastric cancer was associated with cancer progression, liver metastasis, and poor prognosis. Therefore, C5aR may represent a prognostic factor and therapeutic target in gastric cancer.  相似文献   
996.
Principal component analysis was applied to effectively optimize the operational conditions of a fluidized bed granulator for preparing granules with excellent compaction and tablet physical properties. The crucial variables that affect the properties of the granules, their compactability and the resulting tablet properties were determined through analysis of a series of granulation and tabletting experiments. Granulation was performed while the flow rate and concentration of the binder were changed as independent operational variables, according to a two-factor central composite design. Thirteen physicochemical properties of granules and tablets were examined: powder properties (particle size, size distribution width, Carr's index, Hausner ratio and aspect ratio), compactability properties (pressure transmission ratio, die wall force and ejection force) and tablet properties (tensile strength, friability, disintegration time, weight variation and drug content uniformity). Principal component analysis showed that the pressure transmission ratio, die wall force and Carr's index were the most important variables in granule preparation. Multiple regression analysis also confirmed these results. Furthermore, optimized operational conditions obtained from the multiple regression analysis enabled the production of granules with desirable properties for tabletting. This study presents the first use of principle component analysis for identifying and successfully predicting the most important variables in the process of granulation and tabletting.  相似文献   
997.

Objectives

To assess risk of lung cancer (LC) in patients with preinvasive bronchial lesions and to identify factors associated with higher risk.

Methods

124 patients with one or more preinvasive bronchial lesions and normal chest computed tomography (CT) (mean age 66.7 years, 121 males and 3 females), followed-up by white light and autofluorescence bronchoscopy (AFB) every 4-6 mo and chest CT every 6-12 mo, end points were development of carcinoma in situ (CIS) or LC.

Results

Among 124 patients with 240 preinvasive bronchial lesions, 20 CIS or LC lesions were detected during follow-up in 20 (16%) patients, 7 were detected as new endobronchial lesions, 10 as new peripheral lesions and 3 as local progression from severe dysplasia to CIS. Median time to progression from the same site or development of CIS/LC elsewhere was 24 months (range: 6-54 mo). The Cumulative risk of development of CIS/LC was 7% at one year, 20% at three years and 44% at 5 years. Among detected lung cancers, 80% were stage 0 or stage I and underwent treatment with curative intent. Diagnosis of new SD during follow-up (p = 0.0001), chronic obstructive pulmonary disease (COPD) (p = 0.001) or smoking index >52 pack-year (p = 0.042) was associated with higher risk. Even after controlling for other risk factors, COPD was associated with risk for lung cancer. Baseline lesion grade was not predictive of patient outcome (p = 0.146).

Conclusion

Patients with preinvasive bronchial lesions, especially those with new SD during follow-up, COPD or smoking >52 pack-year are at high risk of LC, AFB and CT follow-up facilitated early detection and treatment with curative intent.  相似文献   
998.
Summary The ability of the antiangiogenic agents TNP-470 and minocycline, singly or in combination, to potentiate the antitumor effects of several cytotoxic therapies was assessed in the murine EMT-6 mammary carcinoma as well as in two drug resistant sublines of that tumor designated EMT-6/CTX and EMT-6/CDDP.The antiangiogenic agents alone or in combination did not alter the growth of the tumors. However, their administration along with cyclophosphamide, CDDP, or thiotepa substantially increased the tumor growth delay produced by these cytotoxic therapies in tumors responsive to the drugs — the increase was about 2-fold for TNP-470 and minocycline together. In drug resistant tumors, treatment with the antiangiogenic agents did not reverse drug resistance but did increase the effect of the cytotoxic drugs.Treatment with TNP-470/minocycline also increased the oxygenation of each of the three tumors. Thus, TNP-470/minocycline administration increased the efficacy of fractionated radiation therapy, especially when used along with a perflubron emulsion oxygen delivery agent/carbogen.These results indicate that treatment regimens including therapies directed toward the proliferating normal cells within a tumor mass as well as therapies directed toward the malignant cells can produce improved outcomes.  相似文献   
999.
Despite recent improvements in multimodal therapies for osteosarcoma (OS) and Ewing's family of tumors (EFTs), the prognosis of relapsed cases remains very poor because of the resistance to chemotherapy. Histone deacetylase inhibitors (HDACIs), including members of the cyclic tetrapeptide family such as FK228 and apicidin, are novel antitumor agents that can induce cell cycle arrest and apoptosis in various cancer cells. HDACIs also exhibit potent antitumor effects on OS and EFTs. However, to date there have been no studies to our knowledge reporting the effects of HDACIs on drug-resistant OS and EFTs. Here, we demonstrated that FK228 and apicidin exhibited strong resistance in doxorubicin-resistant clones of OS and EFTs expressing P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP1) and that P-gp and MRP1 might play a crucial role in the resistance mechanism to FK228 and apicidin. A P-gp inhibitor (verapamil) and an MRP1 inhibitor (MK571) could independently reverse the resistance to FK228 and apicidin in the drug-resistant clones. Moreover, the combination of verapamil and MK571 could enhance HDACI-induced cell number reduction in drug-resistant clones to a similar extent as that in their parental clones. Although these findings suggest the difficulty in treating drug-resistant tumors expressing P-gp and/or MRP1 with these HDACIs, the combination of P-gp and MRP1 inhibitors might reverse the resistance to the HDACIs in the treatment of those tumors. Because HDACIs are potent and promising antitumor drugs and seem to be close to clinical use, it is necessary to pay attention to the resistance mechanisms against HDACIs.  相似文献   
1000.
From October 1999 to September 2000, we collected the specimen from 430 patients with lower respiratory tract infections in 17 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various antibacterial agents and antibiotics and patients' characteristics. Of 515 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 506 strains were investigated. The breakdown of the isolated bacteria were: Staphylococcus aureus 78, Streptococcus pneumoniae 101, Haemophilus influenzae 104, Pseudomonas aeruginosa (non-mucoid) 58, P. aeruginosa (mucoid) 11, Moraxella subgenus Branhamella catarrhalis 41, Klebsiella pneumoniae 18, etc. Of 78 S. aureus strains, those with 4 micrograms/ml or above of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) occupied 57.7%. Vancomycin and arbekacin showed the most potent activities against MRSA without detection of ABK-resistant strain (MIC: 64 micrograms/ml) and decrease of VCM-sensitive strains those were found in 1998. The frequency of S. pneumoniae exhibiting low sensitivity to penicillin (penicillin-intermediate S. pneumoniae: PISP + penicillin-resistant S. pneumoniae: PRSP) decreased to 34.7% from 46.0% in 1998. The frequency of PRSP was 3.0%, being the least number after 1991. Carbapenems showed strong activities against S. pneumoniae. Especially, panipenem inhibited the growth of all 101 strains with MIC of 0.063 microgram/ml. Generally, all drugs showed strong activities against H. influenzae with MIC80s of 4 micrograms/ml or below. MICs of ofloxacin ranged between 0.063 microgram/ml and 4 micrograms/ml in 1998, however, those were 0.125 microgram/ml or below in all H. influenzae in 1999 showing the strongest activity. Tobramycin and ciprofloxacin showed strong activities against P. aeruginosa (both mucoid and non-mucoid) with MIC80s of 1 microgram/ml. Number of isolated P. aeruginosa (mucoid) was little as 11, however, the susceptibilities to all drugs were better than P. aeruginosa (non-mucoid). K. pneumoniae showed good susceptibilities to all drugs except for ampicillin with decreasing of low-sensitive strains compared to those detected in 1998. Also, all drugs generally showed strong activities against M. (B.) catarrhalis. MIC80s of all drugs were 2 micrograms/ml or below. The drug which showed the strongest activity was imipenem inhibiting all 41 strains with MIC of 0.063 microgram/ml. On the patients' characteristics, the number of patients aged 80 years or older who had been increased was decreased in 1999 in the distribution by age. The percentage of the elderly patients aged 70 years or older was 47.0%, which occupied almost a half number of the total patients as in the last year. As for the incidence by disease, bacterial pneumonia and chronic bronchitis were the highest. They were noted in 37.9% and 30.5% of the patients, respectively. In 1999, bronchial asthma was frequently observed as compared in recent years. It was noted in about 10% of the patients which is the same % as in bronchiectasis. We examined the number of strains from these patients with infections before and after administration of antibiotics. In patients with bacterial pneumonia, the number of isolated strains was almost the same between those before and after administration. However, in patients with chronic bronchitis, the number of strains remarkably decreased to less than the half of the total after administration of antibiotics in the last year, but it decreased to 2/3 of the total in 1999. On the administration of antibiotics and isolated bacteria by the day of administration, the bacteria which were isolated more before administration were H. influenzae in 28.4%, S. pneumoniae in 25.7%, M. (B.) catarrhalis in 12.0% and S. aureus in 10.6%. The frequency of S. aureus after administration over 15 days was almost the same as that before administration, but the frequency of P. aeruginosa (both mucoid and non-mucoid) was 36.8% which was higher than that before administration. The frequency of isolated S. pneumoniae was decreased after administration and none of them was isolated after completion of administration. However, that of H. influenzae was decreased to 7.1% after administration within 3 days, and many H. influenzae were isolated after completion of administration as 21.4%.  相似文献   
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