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131.
Kasuya H Kikuchi K Imamura T Kawashima A Aihara Y Ochiai T Yamaguchi K Fukamachi K Hori T Shiseki M Tozuka K 《No shinkei geka. Neurological surgery》2000,28(5):429-434
We report here two cases of MRSA sepsis following craniotomy. In case 1, a petroclival meningioma was subtotally removed and lumbar drainage was inserted postoperatively to prevent cerebrospinal fluid leakage. Ventriculo-peritoneal shunt was performed after meningitis was treated with vancomycin and panipenem/betamipron. Two weeks after the procedure, the patient revealed continuous spiking fevers related to MRSA sepsis, which did not improve with vancomycin and arbekacin administration. The focus of infection was found by scintigraphy and CT by 67Ga to be spondylo-diskitis at the level of L2-L3. The lesion was removed and bone from the iliac crest grafted. In case 2, seven days after surgery for multiple meningioma, the patient exhibited spiking fevers and swelling in the left leg. The central venous catheter was removed from the left femoral vein and MRSA was found from blood culture. The patient was treated with arbekacin (200 mg/day). Venous thrombosis diagnosed by CT was treated with heparin. Symptoms related to the infection and laboratory data did not improve because the concentration of arbekacin in the blood did not reach an effective level. The symptoms markedly improved when the dose of arbekacin was doubled (400 mg/day). 相似文献
132.
Expression and functional analyses of breast cancer resistance protein in lung cancer. 总被引:12,自引:0,他引:12
133.
Ki-lantigen(CD3o)waslO5oOo/12oooOglycoproteindistinguishedbymonoclonalantibodyKi-lwhichwasmadefromHodgkin'sdisease(HD)cellsstrainL-428,'eXPressedonHDcellsandReed-Sternberg(R-S)cellsatfirstthoughtItwasfoundbySteinandothersinl985,whonamedKi-lstrongpositiveNHLasKi-llymphoma,thatKi-lantigenwasalsoexpressedonsomeNHL.2Theresearchesonthisspecialtypeoflymphomahavealreadyappearedabroad.WehavecollectedfivecasesofKi-lpositiveNHLandnowdiscusstheirclinicalhistopathologicalandimmunophenotypicfe… 相似文献
134.
Tumor recurrence rate (TRR) and mortality rate (MR) of invasive ductal carcinoma (IDC) of the breast in short-term follow-up are relatively low. Nevertheless, it is extremely important to identify patients at risk of early recurrence or death after surgery. The aim of this study was to establish a new histological prognostic classification scheme for IDC in order accurately to predict the short-term outcome. The following histological parameters were analyzed in 201 IDCs: 1) tumor size, 2) structural atypia, 3) nuclear atypia, 4) number of mitotic figures, 5) fibrotic focus (FF), 6) vascular invasion, 7) tumor necrosis, 8) skin invasion, 9) muscle invasion, 10) nodal status and 11) extramammary fat invasion. Multivariate analysis showed that nuclear atypia, presence of FF, and the invasive length of fat invasion (ILFI) were the most important histological parameters correlated with TRR or MR of IDCs. Accordingly, a new histological classification based on nuclear atypia, FF and ILFI (Nucleus-Fibrotic focus-Fat invasion, NFF) was devised. Comparative studies were performed with the following existing prognostic classifications: 1) histological grade, 2) modified Scarff-Bloom-Richardson histological grade, 3) prognostic index and 4) pathological TNM (pTNM) stage classifications. Patient grouping defined by NFF classification significantly correlated with tumor recurrence or death of IDCs in all cases, cases at stages I and II, those without lymph node metastasis and those who were estrogen receptor (ER)-positive after adjustment for the other four classifications, using multivariate analysis. NFF classification appeared superior to existing prognostic classifications for the accurate prediction of the short-term outcome for patients with IDCs in low risk groups. 相似文献
135.
Wei Yue Steven J. Santner Shigeru Masamura Ji-Ping Wang Laurence M. Demers Christopher Hamilton Richard J. Santen 《Breast cancer research and treatment》1998,49(1):S1-S7
Estradiol stimulates the growth of breast tumor cells in both pre- and post menopausal women. Following the menopause, the levels of estradiol in breast tumor tissues are similar to those from tumors obtained prior to cessation of ovarian function, even though plasma estrogen levels are 10–50 fold lower in post- than in premenopausal women. These observations suggested the possibility of enhanced estradiol uptake from plasma or in situ synthesis in post-menopausal women. We systematically studied these possibilities in a series of model systems. Initially we demonstrated a very high affinity estradiol binding site in tissues from castrated rats. Enhanced uptake occurred under conditions of low plasma estrogen levels when compared to animals with higher estradiol levels. In situ synthesis also occurred both through the sulfatase and aromatase pathways. In further studies, we compared uptake from plasma with in situ synthesis via aromatase in a nude mouse model. Under the conditions utilized, in situ synthesis resulted in much higher tissue estradiol levels and tumor growth rates than did uptake from plasma. During these studies we demonstrated that tumors deprived of estradiol developed mechanisms rendering them more sensitive to estrogen. This involved the ability of cells to adapt to estradiol deprivation to allow them to be responsive to four log lower amounts of estrogen than when studied under wild type conditions. In addition, cells adapted by increasing their level of aromatase and thus developing the capability to become more sensitive to estrogen precursors. Taken together, these studies demonstrate that breast cancer tissue is highly plastic and can adapt to conditions of estrogen deprivation via a variety of mechanisms. 相似文献
136.
Shigeru Imoto 《International journal of clinical oncology / Japan Society of Clinical Oncology》1998,3(2):88-92
Background To investigate whether tamoxifen therapy has a favorable effect on plasma lipids, serum cholesterol levels were measured in
228 Japanese women with breast cancer (116 premenopausal women and 112 postmenopausal women).
Methods These women were treated with tamoxifen or tamoxifen+chemotherapy (tamoxifen-treated group) or were given no therapy or chemotherapy
alone (control group).
Results There was no difference between cholesterol levels before treatment and after a 2-year follow-up period in these groups, except
for the postmenopausal tamoxifen-treated group. In this particular group, the mean levels of serum cholesterol after 1 and
2 years of follow-up (197 and 188 mg/dL, respectively) were 8% and 12% lower than those before treatment (215 mg/dL,P<0.0001). In addition, the mean level of serum cholesterol after a 2-year follow-up period was significantly higher in the
postmenopausal tamoxifen-treated group than in the postmenopausal control group (218 and 188 mg/dL, respectively,P=0.0066).
Conclusions In multiple regression models that included age, body mass index, and chemohormonal therapy, only tamoxifen treatment appeared
to predict the change between cholesterol levels before treatment and after 2-year follow-up in postmenopausal women. These
results suggest that tamoxifen has the potential benefit of reducing the serum cholesterol level, which may be closely related
to cardiovascular risk, in Japanese postmenopausal women. 相似文献
137.
Tomoko Ohtsu Hirofumi Fujii Hisashi Wakita Tadahiko Igarashi Kuniaki Itoh Shigeru Imoto Masahiro Kohagura Yasutsuna Sasaki 《Cancer chemotherapy and pharmacology》1998,42(1):1-8
The present study was conducted to compare the pharmacokinetics (PK) of low-dose versus high-dose medroxyprogesterone (MPA)
as a once-daily oral administration. Of 32 patients, all women, enrolled in this PK study, 18 received 600 mg MPA daily and
14 received 1200 mg daily. Detailed PK data were obtained on day 1 and after more than 4 weeks of MPA treatment. In addition,
multiple data for the minimum steady-state concentration (Css min) were analyzed. The MPA serum concentrations were measured
by high-performance liquid chromatography. Wide interpatient variability was found in the PK parameters obtained both on day
1 and after more than 4 weeks. There were no clear relationships between the oral dose and the MPA peak concentration (Cmax),
area under the time versus concentration curve (AUC), or mean Css min. Weight gains of 10% or more were demonstrated more
frequently in the high-dose group (P<0.01). Liver dysfunction (n=5) did not influence the PK of MPA. Five patients demonstrated extremely low AUC and Cmax (<10 ng/ml) values on day 1. Phenobarbital,
dexamethasone and betamethasone were being taken concomitantly with the MPA each by one patient. The serum MPA concentrations
were markedly increased after the discontinuation of phenobarbital in that patient, suggesting a drug interaction. At present
we cannot recommend the high dose of MPA, except in clinical studies, from a PK or a pharmacodynamic points of view.
Received: 2 May 1997 / Accepted: 13 October 1997 相似文献
138.
目的 研究细胞间信息传递机制之一假单胞菌喹诺酮信号(PQS)在铜绿假单胞菌发病机制中的作用.方法 基于基因融合分析在转录研究中的实用性,构建了两种PQS相关对照质粒和整合突变株.一种是酶切质粒pYHP441获得pqsA'-lacZ片段后,亚克隆入质粒miniCTX-1中,构建成pqsA'的阳性表达质粒,随后将构建的质粒,通过双亲交配过程整合入野生型铜绿假单胞菌株PAO-1染色体组中;另一种是通过点特异插入诱变策略,将四环素基因盒插入启动子pqsD和pqsE之间,构建的阴性质粒转化入大肠杆菌S17-1株后,和上述pqsA'阳性表达突变株进行双亲交配过程.结果 针对今后PQS的相关研究,构建得到稳定表达PQS的质粒和阳性突变株作为阳性对照.构建获得pqsA-E启动子敲除质粒和相应PQS表达受阻的整合突变株作为阴性对照.结论 两种质粒和整合突变株的构建成功,使得PQS的相关研究结论具有客观性、精确性和有效性. 相似文献
139.
Yoichi Kohno Shigeyuki Kitamura Seigo Sanoh Kazumi Sugihara Nariaki Fujimoto Shigeru Ohta 《Drug metabolism and disposition》2005,33(8):1115-1123
When chalcone and trans-4-phenyl-3-buten-2-one (PBO) were incubated with liver microsomes of untreated rats in the presence of NADPH, 4-hydroxychalcone and trans-4-(4-hydroxyphenyl)-3-buten-2-one (4-OH-PBO), respectively, were formed as major metabolites. Two minor metabolites of chalcone, 4'-hydroxychalcone and 2-hydroxychalcone, were also observed. The oxidase activity affording 4-hydroxychalcone was inhibited by SKF 525-A, disulfiram, ketoconazole, and alpha-naphthoflavone. The oxidase activities leading to 4-hydroxychalcone and 4'-hydroxychalcone were enhanced in liver microsomes of 3-methylcholanthrene- and phenobarbital-treated rats, respectively. The activity generating 2-hydroxychalcone was enhanced in liver microsomes of 3-methylcholanthrene- and dexamethasone-treated rats. The oxidation of PBO to 4-OH-PBO was inhibited by SKF 525-A, ketoconazole, disulfiram, and sulfaphenazole. This activity was enhanced in liver microsomes of 3-methylcholanthrene-, acetone- and phenobarbital-treated rats. 4-Hydroxylation, 4'-hydroxylation, and 2-hydroxylation of chalcone were catalyzed by rat recombinant cytochrome P450 1A1, 1A2, and 2C6; by 1A1 and 2C6; and by 1A1 and 3A1, respectively. PBO was oxidized by cytochrome P450 1A1, 1A2, 2C6, and 2E1. Chalcone and PBO were negative in an estrogen reporter assay using estrogen-responsive human breast cancer cell line MCF-7. However, 4-hydroxychalcone, 2-hydroxychalcone, 4'-hydroxychalcone, and 4-OH-PBO exhibited estrogenic activity. 相似文献
140.
Hand-assisted laparoscopic surgery for a large gastrointestinal stromal tumor of the stomach 总被引:6,自引:1,他引:6
Hiroshi Yano Yutaka Kimura Takashi Iwazawa Hirotoshi Takemoto Mitsunobu Imasato Takushi Monden Shigeru Okamoto 《Gastric cancer》2005,8(3):186-192
We report two cases of large gastrointestinal stromal tumor (GIST) of the stomach that were successfully treated by hand-assisted laparoscopic surgery (HALS). Two patients, a 56-year-old woman and a 60-year-old man, were admitted to our department for the treatment of a large submucosal tumor of the stomach. After gastrointestinal endoscopy, ultrasonography, computed tomography, and magnetic resonance imaging, we suspected that the masses, measuring 7.0 cm and 8.0 cm in diameter, respectively, were GISTs in the stomach. However, preoperatively, we could not rule out the possibility of malignant neoplasms, because they had been bleeding or gradually growing. Hand-assisted laparoscopic wedge resection was safely performed for the diagnosis and treatment of the submucosal tumor of the stomach. The immunohistochemical diagnosis in both patients was GIST of the stomach with intermediate-grade malignancy. HALS may be a good indication for large GISTs of the stomach that are difficult to diagnose preoperatively, whether they are malignant or benign, because it is safe and minimally invasive, promoting rapid recovery. 相似文献