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51.
报道辐照氟银猪皮的制备、实验检测(弹性、创面粘附力和透水性测定,含银量测定)组织学检查细菌检测及抑菌试验研究,结果表明:辐照氟银猪皮除延伸度低于未辐照猪皮外,其撕裂强度、创面粘合力和透水性均与未辐照猪皮相似。组织学检查示:辐照氟银猪皮组织结构完整,表皮细胞部分空泡形成。组织细菌检测证明其无菌生长,达到无菌要求。抑菌试验证明对金黄色葡萄球菌、绿脓杆菌、大肠杆菌、变形杆菌、克雷伯氏菌均有极强的抑菌作用  相似文献   
52.
Fetal thrombosis of the dural sinus is an extremely rare congenital cerebrovascular condition that is potentially fatal. We report a case of dural sinus thrombosis diagnosed by prenatal ultrasonography and fetal magnetic resonance imaging (MRI) in the second trimester. The thrombosis showed partial resolution during pregnancy and resolved spontaneously after birth without neurological complications. This is the first report of spontaneous postnatal resolution, and may provide helpful information on the natural history and prenatal counseling of fetal thrombosis of the dural sinus.  相似文献   
53.
A pseudotumor, giant regenerative nodule, or macroregenerative nodule is an unusual benign hepatic lesion in biliary atresia (BA) patients. This tumor may mimic malignant transformation and may preclude liver transplantation (LT). The clinical and imaging surveillance of patients after the Kasai procedure is therefore an important aspect of management of BA patients. Our objective is to report our experience and describe the incidence, imaging, and pathologic features of pseudotumors in BA patients awaiting LT. From August 1990 to December 2006, 133 LTs for BA were performed. Five (3.8%; 4 female, 1 male) patients were diagnosed with pseudotumor. The patients' records were reviewed. The diagnostic imaging modalities used were abdominal ultrasound (US), computed tomography (CT) scan, and magnetic resonance imaging (MRI). Histologic confirmation of the lesions was obtained in all cases. All underwent the Kasai operation in early infancy. Six of 7 lesions in 4 of 5 patients were demonstrated by pretransplant imaging. Two of 7 tumors were detected by US. Five of 7 lesions were detected by CT, and 5 of 7 lesions were demonstrated by MRI. In 1 patient, the lesion was not seen in the US, CT, or MRI but was found during surgery and confirmed by histology. An additional tumor was found incidentally during histologic examination in a patient previously diagnosed to have 2 tumors by CT and MRI. In another patient diagnosed to have 2 tumors on imaging, pathology revealed only a single tumor. In conclusion, although unusual, pseudotumor should be included in the differential diagnosis of liver masses in BA children.  相似文献   
54.
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   
55.
Foreign bodies in the heart are a rare but serious form of cardiac injury. The objects usually are sharp pointed. Such as acupuncture needles,sewing needles, coat hangers, fragments of Kirschner wires, pins, etc. 1 We report a patient with a metallic pellet lodged in the heart, which was accurately diagnosed and successfully removed.  相似文献   
56.
The X‐linked McLeod neuroacanthocytosis syndrome strongly resembles Huntington's disease and has been reported in various countries world‐wide. Herein, we report two Chilean brothers with predominant psychiatric features at disease onset including schizophrenia‐like psychosis and obsessive compulsive disorder. Molecular genetic analysis revealed a small deletion in the XK gene (938‐942delCTCTA), which has been already described in a North American patient of Anglo‐Saxon descent and a Japanese family, presenting with seizures, muscle atrophy or chorea yet absence of psychiatric features. These findings argue against a founder effect and indicate a profound phenotypic variability associated with the 938‐942delCTCTA deletion. Our report supports the inclusion of McLeod syndrome in the differential diagnosis of Huntington's disease as well as acute psychosis in male subjects. © 2007 Movement Disorder Society  相似文献   
57.
目的:观察3种常用化疗药对正常大鼠血清胃泌素及D-木糖醇浓度的影响。方法:将动物随机分为4组,即对照组、ETX组、5-Fu组和THP组,检测胃泌素及D-木糖醇浓度等指标。结果:3组化疗组上述指标与对照组比较,差异有统计学意义(P〈0.05,P〈0.01)。结论:正常大鼠用ETX、5-Fu和THP,血清胃泌素及D-木糖醇浓度明显减低,从临床表现、胃肠功能方面提示3种常用化疗药可导致正常大鼠脾虚证的发生。  相似文献   
58.
OBJECTIVE: To evaluate the possibility and reliability of the hyoid-sternohyoid graft transfer in the correction of server subglottic laryngotracheal stenosis, and delineate the operation skills and clinical results. METHODS: Seven patients with severe subglottic stenosis underwent laryngotracheal reconstruction using the hyoid grafts with sternohyoid muscle flaps (HG-SHMF). Five of these patients had traumatic subglottic stenosis, one with scar tissue of unknown etiology arising in the subglottic region, another with tracheal narrowing caused by inhalation of hydrochloric acid. RESULTS: All seven patients were successfully decannulated with moderate good voice. The average time from reconstruction to decannulation was 15.4 months. The stent was endoscopically removed with a range of 3 to 22 months; the mean time required for stenting was 9.6 months. Two patients who received additional salvage reconstruction procedures because of graft or stent displacement were extubated with improved voices and satisfactory airway. CONCLUSIONS: The HG-SHMF transfer was a single-stage reconstruction, relatively simple procedure that can restore an adequate airway and a good voice. Patients undergoing laryngotracheal reconstruction with HG-SHMF must have regular, long-term follow-up since graft displacement and recurrent granulation tissue or scar reformation can cause restenosis after an initially successful surgery. This procedure should be used in a large number of patients to further test its reliability.  相似文献   
59.
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02 per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05) than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy.  相似文献   
60.
Poly(arylene-1,2,4-oxadiazole)s (PAOs) bearing flexible, linear side chains, 3a - c , were prepared by solution cyclodehydration of their precursors, poly(arylene acyloylamide oxime)s (PAAs), 2a - c , which were synthesized by solution polycondensation of 2,5-bis(n-alkoxymethyl)-terephthaldiamide oximes (DIS-TADO), 1a - c , with terephthaloyl dichloride (TPC). The length of the n-alkoxy group was varied from methoxy via butoxy to octyloxy. The reduction of the phase transition temperatures and the enhancement of the solubilities of 3a - c were greatly affected by the length of the side chains. PAOs with longer side chains, 3b and 3c , are nematic type liquid-crystalline polymers.  相似文献   
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