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91.
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
92.
Taiki Matsunaga Yuki Kamachi Koichi Kinoshita Tetsuya Sakamoto Takuaki Yamamoto 《The Journal of arthroplasty》2021,36(2):429-433
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
93.
94.
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
95.
Tsukamoto F Shiba E Taguchi T Sugimoto T Watanabe T Kim SJ Tanji Y Kimoto Y Izukura M Takai SI 《Breast cancer (Tokyo, Japan)》1997,4(4):259-263
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
96.
Finger bougie method compared with pyloroplasty in the gastric replacement of the esophagus 总被引:2,自引:0,他引:2
Yamashita Y Hirai T Mukaida H Yoshimoto A Kuwahara M Inoue H Toge T 《Surgery today》1999,29(2):107-110
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
97.
Changes in optic nerve head blood flow and retrobular hemodynamics following calcium-channel blocker treatment of normal-tension glaucoma 总被引:2,自引:0,他引:2
Tomita G Niwa Y Shinohara H Hayashi N Yamamoto T Kitazawa Y 《International ophthalmology》1999,23(1):3-10
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
98.
Hydroxyamino, nitroso and nitro derivatives of 3-amino-1-methyl-5H-pyrido[4,3-b]indole(Trp-P-2) and 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole(Glu-P-1), mutagens-carcinogens produced on pyrolysis of aminoacids, were synthesized from Trp-P-2 and Glu-P-1. 3-Hydroxyamino-1-methyl-5H-pyrido[4,3-b]indole(N-OH-Trp-P-2) and 2-hydroxyamino-6-methyldipyrido[l,2-a:3',2'-d]imidazole (N-OH-Glu-P-1) were obtained with good yieldsby controlled catalytic reduction of 3-nitro-l-methyl-5H-pyrido[4,3-b]indoleand 2-nitro-6-methyldipyrido[1,2-a:3',2'-d]imidazole. Subsequentoxidation of N-OH-Trp-P-2 and N-OH-Glu-P-1 with -manganese dioxideyielded 3-nitroso-1-methyl-5H-pyrido[4,3-b]indole and 2-nitroso-6-methyldipyrido[1,2-a:3',2'-d]imidazole.All six synthesized compounds were mutagenic to Salmonella typhimuriumTA98 without mammalian activation systems. The mutagenic activitiesof hydroxyamino and nitroso derivatives were identical for bothS. typhimurium TA98 and TA98NR, the nitroreductase deficientstrain. However, nitro derivatives were essentially mutageniconly towards S. typhimurium TA98. 相似文献
99.
Tetsuya Yamada Gaku Ichihara Hailan Wang Xiaozhong Yu Kei-ichiro Maeda Hiroko Tsukamura Michihiro Kamijima Tamie Nakajima Yasuhiro Takeuchi 《Toxicological sciences》2003,71(1):96-103
Although 1-bromopropane has been used in chemical and electronic industries as an alternative to ozone layer-depleting solvents, its toxicity on female reproductive organs has not been fully elucidated. The aim of this experiment was to determine the effect of 1-bromopropane on female reproductive function in rats. Forty female Wistar rats were divided into four equal groups. Each group was exposed daily to 0, 200, 400, or 800 ppm of 1-bromopropane for eight h a day. After exposure for 7 weeks, all rats in the 800-ppm group became seriously ill and were sacrificed during the 8th week. The other dose groups were exposed for 12 weeks. In the 800-ppm group, but not in the other two exposed groups, body weight was significantly less than the control at each time point from 2 to 7 weeks after the beginning of exposure. Tests of vaginal smears showed a significant increase in the number of irregular estrous cycles with extended diestrus in the 400- and 800-ppm groups. Histopathological examination of the ovary showed a significant dose-dependent reduction of the number of normal antral follicles and a decrease in the number of normal growing follicles in the 400-ppm group. No significant change was found in plasma concentrations of LH or FSH in any group when compared with the control. Our results indicate that 1-bromopropane can induce a dose-dependent ovarian dysfunction in nonpregnant female rats associated with disruption in follicular growth process. 相似文献