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81.
Lymphokine-activated killer (LAK) cells were induced with low-dose recombinant interleukin 2 (rIL-2) and recombinant interferon- (IFN-) in 28 oral carcinoma patients. The patients received daily intravenous injections of rIL-2 (1.2×105 U/m2) and rIFN- (7.0×104 U/m2), and both natural killer (NK) and LAK activities were periodically examined. A significant increase in CD16+CD57+ and CD16+CD57 NK subsets was observed after the induction. An increase in the T-cell population was also found, with a significant increase in CD3+HLA-DR+, CD8+Leu8, and CD4+Leu8 cells. Significant increases in NK activity, from the original level of 32.0±13.7 to 49.9±15.2%, and LAK activity, from 4.8±3.5 to 11.0±6.1%, at Day 7 were observed. Both activities were maintained at high levels during the cytokine injections, but greater enhancement of the killing activities could not be obtained subsequently. When NK and LAK activities were investigated in each subpopulation of CD3 and CD16 cells, no remarkable cytotoxic activity could be observed before induction in any subset without NK activity in CD3 cells (31.1±14.3%). At Day 7, NK activity of CD16 cells increased up to 21.4±14.9%, accompanied by an increase in CD3-cell activity (54.5±20.6%). LAK activities of both subsets were also enhanced, with activity at Day 7 of 6.5±5.6 and 9.4±6.6% in CD16 and CD3 cells, respectively. These increased activities were maintained at the same level during the induction. Phorbol myristate acetate-induced polymorphonuclear leukocyte (PMNL) O 2 generation was significantly increased, from the original 81.1±28.1 to 95.6±34.9 pmol/min/104 cells, after 1 week of treatment. Protein kinase C activity in the cytosol decreased, and the activity in the membrane fraction conversely increased. No remarkable adverse effects except for mild fever were observed. Together with LAK induction ability and PMNL enhancement, with scarce toxicity, a combination of low-dose rIL-2 and rIFN- is thought to be useful in cancer treatments.  相似文献   
82.
Two clones, pCZTH5-8 and pCZTH12-8, were isolated from a female chicken genomic library by screening with sequences obtained from genomic libraries which had been constructed from a terminal region of a single Z chromosome of chicken utilizing laser microbeam irradiation and PCR amplification. Fluorescencein situ hybridization to the mitotic Z chromosome and the lampbrush ZW bivalent of chicken demonstrated that both the cloned sequences are located in the heterochromatic region of the Z chromosome at the end opposite to the pairing region with the W chromosome. The sequences pCZTH5-8 and pCZTH12-8 are distributed widely on both the telomeric bow-like loops (TBL) and the region I (short loops region) of the Z lampbrush chromosome. These clones, pCZTH12-8 particularly notably, hybridized also to the TBLs of lampbrush bivalents 1–4 of chicken. Both sequence are transcribed in the lampbrush stage oocytes on the Z chromosome and on other macrobivalents. The subfragment of pCZTH5-8 which hybridizes to the TBLs and the insert of pCZTH12-8 contain regions that are closely similar in sequence. The pCZTH5-8 sequence has no internal repeats and may be part of the 24-kb macrosatellite repeating unit that is evident afterNhel digestion of the genomic DNA. A cloned 24-kb unit, pFN-1, does not show significant DNA curvature, but cytosines of its CpG dinucleotides may be highly methylatedin vivo. This contrasts with the repeat sequences of the W heterochromatin which not only have highly methylated CpG but are also strongly curved. The 24-kb unit is repeated about 830 times in the diploid genome of a female chicken, suggesting that nearly the entire terminal heterochromatin on the Z chromosome consists of this macrosatellite family. Sequences of the greater part of the pCZTH5-8 are restricted to the genusGallus but the sequence of one subregion which hybridizes to TBLs is present in the genomes of the order Galliformes.accepted for publication by M. Schmid  相似文献   
83.
何剑  郑俐慧 《当代医学》2001,7(2):58-60
1 介绍 当前心脏检查中急需解决的问题是无创地用超声心动图客观地、定量地评价心功能。在常规的彩色多普勒成像(CDI)技术基础上发展起来的组织多普勒成像(TDI)技术,让这些成为可能。组织多普勒成像是通过测量心室壁的运动速度来定量评价心功能。它最初是被用来评价缺血性心脏病(心肌梗塞,心绞痛等)的,其主要目的是客观、精确地识别引起心功能减  相似文献   
84.
BackgroundCurved periacetabular osteotomy (CPO) is performed via an anterior approach without detachment of the hip abductor muscles. This study aimed to evaluate the abductor muscle status shortly after CPO on magnetic resonance imaging (MRI).MethodsWe prospectively evaluated 38 hips in 38 patients 1 week and 3 months after CPO between October 2017 and July 2019. The status of the abductor muscles was assessed on MRI using the following criteria: grade 0, normal; grade I, strain/edema; grade II, partial tear; and grade III, complete tear. We also evaluated associations between muscle status and patients’ characteristics.ResultsOne week after CPO, the gluteus maximus was classified as grade 0 in all patients. The gluteus medius was grade 0 in 84.2% of patients and grade I in 15.8%. The gluteus minimus was grade I in 55.3% of patients and grade II in 44.7%. Three months after CPO, both the gluteus maximus and gluteus medius were grade 0 in all patients, while the gluteus minimus was still grade I in 47.4%. There were no significant differences between patients with a grade 0 and grade I gluteus minimus at 3 months after CPO in patients’ characteristics (age and body mass index) or clinical scores (Harris Hip Score and Japanese Orthopedics Association score).ConclusionBoth the gluteus minimus and medius showed abnormal appearances on MRI 1 week after CPO, whereas only the gluteus minimus showed abnormalities 3 months after CPO. This abductor muscle status did not affect the postoperative Harris Hip Score or Japanese Orthopedics Association score.  相似文献   
85.
86.
Thirty-two patients with advanced breast cancer refractory to combination chemotherapy with cyclophosphamide (CPA), doxorubicin (ADR) and 5-fluorouracil (5-FU) (CAF) were treated with the combination of mitomycin C, etoposide, doxifluridine and medroxyprogesterone acetate as second line therapy. Observed responses included 6 patients (18.7%) with complete response (CR) and 7 (21.9%) with partial response (PR). Two (50%) out of 4 patients who had bone pain due to bone metastasis noted pain relief. CR or PR were obtained in 4 out of 12 patients who had not responded to the previous CAF therapy. While grade III myelosuppression was observed in 3 patients, other adverse effects were minimal. It is suggested that this combination therapy may be recommended for advanced breast cancer patients as a second therapy.  相似文献   
87.
Overexpression of P-glycoprotein (Pgp) in tumors is one of the major mechanisms which mediates the multidrug resistance (MDR) phenotype. To evaluate the prognostic significance of Pgp in breast cancer, Pgp expression was examined in paraffin-embedded tissue sections of 94 breast cancer specimens by immunohistochemistry. Tissue specimens were obtained by mastectomy without preoperative chemotherapy. UIC2 monoclonal antibody which recognizes an extracellular epitope of human Pgp was employed. Of the 94 breast cancer specimens, 35 (37.2%) were positive for Pgp expression. Pgp expression had no correlation with menopausal or hormone receptor status, axillary lymph node involvement or tumor size. However, a significant correlation was observed between Pgp expression and disease relapse (p = 0.0322). Pgp-positive patients showed a significantly shorter disease-free survival period than Pgp-negative patients by the Kaplan-Meier method (p = 0.0433). These results suggest that immunohistochemical detection of Pgp in breast cancer tissue may have prognostic value after radical operation.  相似文献   
88.
To elucidate the necessity of pyloroplasty for the gastric tube through the posterior mediastinum in esophageal surgery, gastric emptying and duodenogastric reflux (DGR) were evaluated in 16 cases undergoing an anterior pylorectomy (group P) and in 16 cases treated by the finger bougie method (group F). First, the obstruction and reflux symptoms were examined based on a patient questionnaire using a brief scoring system. The median value of the symptom score showed the patients in P to have more symptoms than those in F; however, the difference was not significant (8.0 vs 6.0). Secondly, the swallowed Tc O4 (85 MBq) was counted using a gamma camera at three sites on the sternal bone in the upright position based on a gastric transit scintigram. Both the descending time of the RI peak and the clearance rates were similar between the two groups. Thirdly, intragastric 24-h pH monitoring was carried out. Antimony pH sensors were anchored 5 and 15 cm below the esophagogastrostomy. We could not find any difference between the two groups in both the % time pH>4 and %time pH>7. These findings thus revealed no big difference between groups P and F. The finger bougie method to drain the vagotomized posterior mediastinal stomach was found to achieve results similar to conventional pyloroplasty, while it was also simpler and safer.  相似文献   
89.
90.
Background: Because calcium channel blockers reduce vascularresistance, they may have a clinical application in the treatment ofnormal-tension glaucoma (NTG). This study investigates changes inboth the optic disc blood flow and the hemodynamics of retrobulbarvessels in NTG patients after the systemic administration of a calcium channel blocker. Methods: Twelve eyes of 12 NTG patients (meanage 57 6 ± 15.3 years) were examined before and after a 4-weektreatment with 2 mg b.i.d. oral nilvadipine, an L-typc calcium channel blocker. By scanning laser-Doppler flowmetry (SLDF), we obtained the velocity, flow, and volume from within a 10 × 10 pixel windowplaced on the temporal rim region of the optic disc perfusion map. Byultrasound color Doppler imaging (CDI), we measured the peak systolicvelocity (PSV) and the end diastolic velocity (EDV) of the ophthalmicartery (OA), central retinal artery (CRA), nasal posterior ciliary artery (NPCA), and temporal posterior ciliary artery (TPCA). We then calculated a resistance index (RI) for each vessel. Results: After treatment, the flow and velocity of the optic disc blood flow significantly increased (P < 0.05).Nilvadipine also significantly reduced RIs of the CRA, NPCA, and TPCA(P <0 .05), and increased both the PSV of the NPCA and the EDVs of the CRA, NPCA, and TPCA. The percent change in velocity correlated significantly with the percent changes of the CRA RI and NPCA RI. Conclusions: Oral nilvadipine appears to reduce orbital vascular resistance, which consequentlyincreases the optic disc blood flow. Abbreviations.BP – blood pressure;CRA – central retinal artery;CDI – ultrasound color Doppler imaging;EDV – end diastolic velocity;NPCA – short posterior ciliary arteries located nasal to optic nerve;NTG – normal-tension glaucoma;OA – ophthalmic artery;PP – perfusion pressure;PSV – peak systolic velocity;RI – resistance index;SLDF scanning laser-Doppler flowmetry;TPCA – short posterior ciliary arteries locatedtemporal to optic nerve.  相似文献   
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