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31.
The effect of ibopamine (IBO) (SB 7505, SK&F 100168-A), a new drug for the treatment of congestive heart failure, and its active metabolite epinine (EPN) (N-methyldopamine), on the catecholamine content of hypothalamus and brainstem was studied in vitro after monoamine oxidase inhibition with pargyline. IBO and EPN increased levels of epinephrine (EPI) in a concentration- and time-dependent manner in both brain areas without significantly affecting the concentration of other catecholamines. Inhibition of either dopamine beta-hydroxylase, the neuronal EPI and norepinephrine uptake system, or esterase hydrolysis of IBO prevented the increase of EPI, whereas inhibition of phenylethanolamine N-methyltransferase, enzymatic dealkylation or the neuronal dopamine or serotonin uptake system had no influence on the increase of EPI levels. These results suggest that IBO after hydrolysis to EPN can be converted enzymatically to EPI by dopamine beta-hydroxylase in hypothalamus and brainstem. EPN seems to be accumulated into adrenergic and noradrenergic neurons by the high affinity uptake system. Changes in the EPI content of the central nervous system neurons might be responsible for some of the pharmacologic effects of IBO.  相似文献   
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33.
The immediate, short-term and long-term depressor effects, the immediate effects on cardiac functions in grade II and grade III vascular hypertension, and the effects on angiotensin II in grade III vascular hypertension by acupuncture at otoacupoint Heart were studied in 30 cases of vascular hypertensive patients. The immediate depressor effect of acupuncture at otoacupoint Stomach was also recorded for comparison. It was found that acupuncture at otoacupoint Heart produced marked immediate depressor effect, and the short-term effective rate was 100%, the long-term effective rate was 63.3%, as well as evident immediate effects on cardiac functional activities in grade II and grade III hypertension and marked effects on angiotensin II in grade III hypertension. Acupuncture at otoacupoint Stomach produced no depressor effect on vascular hypertension.  相似文献   
34.
51例应用Begg正畸技术矫治错畸形,各种类型的牙性及轻度骨性错畸形,均取得满意的效果。对牙轴唇倾并伴有深覆的安氏Ⅱ类错打开咬合、内收前牙的效果尤佳。  相似文献   
35.
超声引导下肿瘤内注射^90钇玻璃微球的肝癌综合治疗   总被引:12,自引:0,他引:12  
董宝玮  梁萍 《中华医学杂志》1994,74(8):471-473,T048
超声引导下对28例肝癌病人进行了肿瘤内注射^90钇玻璃微球(Y-90GT MS)为主的综合性治疗(部分病人配合肿块周边注射无水酒精及门静脉穿刺化疗)。随访2~16个月(平均7.9个月),病人全健在。肿瘤缩小率为91%,其中显著缩小达75%;肿块回声呈致密增强,少数呈混合型或等回声型;肿瘤内及周边血流信号显著减少;原甲胎蛋白升高者13例,11例显著下降,其中6例降至正常;病人症状减轻,全身情况改善。  相似文献   
36.
The over-representation of chromosome 12p sequences is crucial for the development of invasive testicular germ cell tumors. Testicular cancer patients may have metastatic tumors of diverse histologic types, including adenocarcinoma, undifferentiated carcinoma, sarcoma, or other malignancies that lack features of germ cell tumors. We sought to investigate the possible germ cell origin of such tumors using interphase fluorescence in situ hybridization. In all, 10 metastatic malignant somatic-type tumors from patients with histories of testicular cancer, as well as one malignant somatic-type tumor from a patient with primary mediastinal germ cell tumor were studied and included: adenocarcinoma (five cases), poorly differentiated carcinoma (one), sarcoma (four), and neuroendocrine carcinoma (one). The tumors were analyzed using fluorescence in situ hybridization using 12p spectrum green and 12 centromeric spectrum orange probes in paraffin sections. The patients ranged in age from 27 to 55 years (mean, 43). Colon and lung cancers from patients without germ cell tumors were used as controls. Adequate signals were observed in all tumors. Gain of chromosome 12p was seen in six tumors. None of the control tumors showed 12p amplification. Fluorescence in situ hybridization for 12p amplification in routinely processed surgical specimens is a useful adjuvant diagnostic tool in confirming the germ cell origin of metastatic tumors having the histologic appearance of somatic-type neoplasms.  相似文献   
37.
段金生  姚咏芳 《上海口腔医学》2004,13(2):146-146,149
复习46例延迟复位固定的颌骨骨折病例,对延迟复位固定的时间、原因、治疗和愈合情况等进行回顾分析:延迟时间最短2d,最长12d;延迟治疗的原因多种多样,所有病例均采用手术治疗。结果,延迟2~5d复位同定者6例,均一期愈合;延迟5-10d复位同定者31例,27例一期愈合;延迟10-12d复位固定者9例,均一期愈合。  相似文献   
38.
OBJECTIVE: Septal-lateral annular cinching ('SLAC') corrects both acute and chronic ischemic mitral regurgitation in animal experiments, which has led to the development of therapeutic surgical and interventional strategies incorporating this concept (e.g., Edwards GeoForm ring, Myocor Coapsys, Ample Medical PS3). Changes in left ventricular (LV) transmural cardiac and fiber-sheet strains after SLAC, however, remain unknown. METHODS: Eight normal sheep hearts had two triads of transmural radiopaque bead columns inserted adjacent to (anterobasal) and remote from (midlateral equatorial) the mitral annulus. Under acute, open chest conditions, 4D bead coordinates were obtained using videofluoroscopy before and after SLAC. Transmural systolic strains were calculated from bead displacements relative to local circumferential, longitudinal, and radial cardiac axes. Transmural cardiac strains were transformed into fiber-sheet coordinates (X(f), X(s), X(n)) oriented along the fiber (f), sheet (s), and sheet-normal (n) axes using fiber (alpha) and sheet (beta) angle measurements. Results: SLAC markedly reduced (approximately 60%) septal-lateral annular diameter at both end-diastole (ED) (2.5+/-0.3 to 1.0+/-0.3 cm, p=0.001) and end-systole (ES) (2.4+/-0.4 to 1.0+/-0.3 cm, p=0.001). In the LV wall remote from the mitral annulus, transmural systolic strains did not change. In the anterobasal region adjacent to the mitral annulus, ED wall thickness increased (p=0.01) and systolic wall thickening was less in the epicardial (0.28+/-0.12 vs 0.20+/-0.06, p=0.05) and midwall (0.36+/-0.24 vs 0.19+/-0.11, p=0.04) LV layers. This impaired wall thickening was due to decreased systolic sheet thickening (0.20+/-0.8 to 0.12+/-0.07, p=0.01) and sheet shear (-0.15+/-0.07 to -0.11+/-0.04, p=0.02) in the epicardium and sheet extension (0.21+/-0.11 to 0.10+/-0.04, p=0.03) in the midwall. Transmural systolic and remodeling strains in the lateral midwall (remote from the annulus) were unaffected. CONCLUSIONS: Although SLAC is an alluring concept to correct ischemic mitral regurgitation, these data suggest that extreme SLAC adversely effects systolic wall thickening adjacent to the mitral annulus by inhibiting systolic sheet thickening, sheet shear, and sheet extension. Such alterations in LV strains could result in unanticipated deleterious remodeling and warrant further investigation.  相似文献   
39.
BACKGROUND AND PURPOSE: The potential risk of prolongation of treatment time in cervical cancer has been reported for many low-dose rate (LDR) studies, with an estimated loss of local control ranging from 0.3 to 1.6% per day of treatment prolongation. Since the treatment schedule for fractionated high-dose rate intracavitary brachytherapy (HDRICB) is not directly comparable with that for low-dose rate studies, this report aims to evaluate the adverse effect of treatment prolongation specifically for cervical cancer treated with HDRICB. MATERIAL AND METHODS: From September 1992 to December 1997, 257 patients diagnosed with uterine cervical cancer (35 Ib, 26 IIa, 122 IIb, 10 IIIa, 57 IIIb, 7 IVa), who underwent external radiotherapy combined with between two and four courses of HDRICB and a minimum of 3 years of follow-up (median 57 months), were analyzed. Treatment consisted of irradiation of the whole pelvis with 44-45 Gy consisting of 22-25 fractions by 5 weeks, with the dose boosted to 54-58 Gy (with central shielding) for patients diagnosed as FIGO stage IIb-IVa bilateral parametrial disease. HDRICB was performed using an Ir-192 remote afterloading technique at 1-week intervals. The standard prescribed dose for each course of HDRICB was 7.2 Gy to point A for three insertions (before July 1995), or 6.0 Gy to point A for four insertions (after July 1995). Total prescribed point A doses (external beam radiotherapy+HDRICB) ranged from 58 to 71.6 Gy (median, 65.6 Gy) for stage IB-IIA, while analogous dosage for larger lesions (stage IIb-IVa) ranged from 59 to 75.6 Gy (median, 65.6 Gy). Kaplan-Meier and multivariate analyses were used to test the effect of treatment time on pelvic control rate (PCR) and cause-specific survival (CSS) at 5 years. RESULTS: Median treatment time was 63 days. For all stages of disease, the 5-year CSS and PCR were significantly different comparing treatment times of less than and greater than or equal to 63 days [83% and 65% (P=0.004], 93% and 83% (P=0.02), respectively]. These associations were also significant for stage Ib/IIa [97% and 79% (P=0.01), and 100% and 87% (P=0.02), respectively), but not for stage IIb [75% and 72% (P=0.79), and 93% and 87% (P=0.83), respectively] or stage III [66% and 49% (P=0.2), and 83% and 72% (P=0.21), respectively]. Multivariate analysis identified three prognostic factors for CSS, stage (P<0.001), tumor response to external RT (P=0.001), and overall treatment time (OTT; P=0.006). Prognostic factors for pelvic failure were stage (P<0.001), tumor response to external RT (P=0.001), and OTT (P=0.03). Prolongation of treatment time resulted in a daily decrease in pelvic control rate of 0.67% overall, and 0.43% for stage Ib-IIa, 0.57% for stage IIb, and 0.73% for stage III patients. CONCLUSION: Analysis of the data from the current study demonstrates that the adverse effect of treatment prolongation was observed later in the treatment course for the high-dose rate (HDR) series compared to the LDR analog, however, treatment-time prolongation still negatively influenced the cause-specific survival and pelvic control rate for both dosage groups.  相似文献   
40.
医源性桡神经损伤46例分析   总被引:1,自引:0,他引:1  
目的阐述医源性桡神经损伤的伤因、治疗和预防措施。方法分析1991年~2003年间收治的46例医源性桡神经损伤的病例。结果伤因分为上肢手术误伤,肱骨干和桡骨上端闭合性骨折复位手法不当,头静脉穿刺致桡神经浅支损伤。本组21例保守治疗,22例手术治疗,3例行肌腱转位功能重建。结论手术误伤是医源性桡神经损伤的首要原因;临床医生丰富的解剖知识和细致、轻柔的操作是预防医源性桡神经损伤的关键。  相似文献   
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