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11.
Purpose: To investigate the relationships between the axonal sprouting and target neurotization by central neurons after nerve heterocon-nection. Methods: Unilateral (right) vagal-hypoglossal nerve anastomosis (VHA) was performed in adult cats. Following 3-315 days postoperation (dpo), quantitative analyses and ultrastructural changes in the proximal portion of the vagal-hypoglossal heteroconnected nerve as well as the time course of neuronal regeneration were studied. Along with this, horseradish peroxidase (HRP) retrograde tracing technique was used to label the neurons of dorsal motor vagal nucleus (DMV) and nucleus ambiguus (NA) to ascertain if target neurotization was established. Results: The contralateral (left) intact vagus nerve proximal to the level of ansa cervicalis showed an average of 33 +/- 1 myelinated and 74 +/- 4 unmyelinated axons in 727 &mgr;m(2) sectional area of the nerve. In the heteroconnected nerve at the corresponding level just proximal to the anastomosis site, there was a marked increase in the number of small axons sprouting from the unmyelinated nerve fibers between 18 and 25 dpo. The number of these axonal sprouts appeared to decline at 32 dpo but its increase of 131 % was sustained until the late regeneration stage at 315 dpo when compared with the contralateral nerve serving as a control. The mean number of myelinated axons per area unit (727 &mgr;m(2)) was reduced to 18 at 3 dpo but was immediately restored to the normal range at 7 dpo. The retrograde labelling of neurons in both the DMV and NA was first detected at 22 dpo and was progressively increased peaking by about 67 dpo. Conclusions: We conclude that compared with the unmyelinated axons, the myelinated axons may acquire a superior interaction with the new target. Furthermore, the postoperative neurotization of tongue muscles may initiate and facilitate the retraction of the redundant axonal sprouts.  相似文献   
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抗CCT2单克隆抗体博来霉素A6偶联物可吸附胶体金颗粒(McAb-A6-Au)。电镜观察表明,在4℃,1h,表面有McAb-A6-Au颗粒的CEM细胞最高达78%;在37℃,4h,内化McAb-A6-Au颗粒的CEM细胞高达72%。而抗原性无关的U937细胞仅为14%。并且McAb-A6-Au颗粒能直接穿过细胞膜、核膜进入细胞浆和细胞核。37℃,1h已有10~18%的CEM细胞核内有McAb-A 6-Au颗粒。实验结果提示了单抗与博来霉素A6的偶联物与选择性地结合靶细胞,而且进入细胞速度快、穿透力强,有可能成为治疗白血病药物。  相似文献   
14.
This empirical study identifies the negative aspects of private health insurance (PHI) by analyzing the association between subjective health conditions, 2 weeks of outpatient care, chronic diseases, and hospitalizations for 1 year. We used frequency analysis, χ2 testing, an analysis of variance, and logistic and multiple logistic regression models to analyze the association between PHI and subjective health conditions, outpatient care, chronic disease status, and hospitalization. The PHI group had good subjective health but had more outpatient care for 2 weeks. There were few chronic diseases in the private insurance group, and there was no significant difference in hospitalizations for 1 year. Hospitalization may occur when essential medical care is required, regardless of health insurance type. This study confirmed that as the PHI lowers the burden of personal medical expenses, the PHI can lead to an increase in the medical resource expenditures on the outpatient medical service and higher public health costs. The government should work to redefine the role of private and national health insurance. Also, the effectiveness of PHI should be reevaluated so that it does not lead to indiscriminate use of medical services by minimizing the burden of private insurance.  相似文献   
15.
0引言创伤,特别是交通伤已成为人类一大公害,国外从本世纪40年代开始进行实验研究,早期实验研究无论是用自由落体式或摆锤式致伤撞击装置,不仅体积大且笨重,最大缺点是不能模拟高速致伤条件[‘·’j.随后有人用撞击枪制造动物创伤模型,显提高了撞击速度,机型较小,使用方便,但其速度和压缩幅度不易掌握.本世纪80年代初美国通用汽车公司首先设计制作出气动式撞击机,使撞击速度大大提高.1993年国内第三军医大学野战外科研究所报道在BIM-1型(自由落体式)生物撞击机基础上研制出一台BIM-I型(气动式)生物撞击机「‘’.我…  相似文献   
16.
We explored the physiological effects of inhaling basil essential oil (BEO) and/or linalool and identified odor-active aroma compounds in BEO using gas chromatography/mass spectrometry (GC–MS) and GC–olfactometry (GC–O). Linalool was identified as the major volatile compound in BEO. Three groups of rats were administered BEO and linalool via inhalation, while rats in the control group were not. Inhalation of BEO for 20 min only reduced the total weight gain (190.67 ± 2.52 g) and increased the forced swimming time (47.33 ± 14.84 s) compared with the control group (219.67 ± 2.08 g, 8.33 ± 5.13 s). Inhalation of BEO for 5 min (392 ± 21 beats/min) only reduced the pulse compared with the control group (420 ± 19 beats/min). Inhalation of linalool only reduced the weight of white adipose tissue (5.75 ± 0.61 g). The levels of stress-related hormones were not significantly different among the groups. The total cholesterol and triglyceride levels decreased after inhalation of BEO for 20 min (by more than −10% and −15%, respectively). Low-density lipoprotein cholesterol levels were lowered (by more than −10%) by the inhalation of BEO and linalool, regardless of the inhalation time. In particular, BEO inhalation for 20 min was associated with the lowest level of low-density lipoprotein cholesterol (53.94 ± 2.72 mg/dL). High-density lipoprotein cholesterol levels increased after inhalation of BEO (by more than +15%). The atherogenic index and cardiac risk factors were suppressed by BEO inhalation. Animals exposed to BEO and linalool had no significant differences in hepatotoxicity. These data suggest that the inhalation of BEO and linalool may ameliorate cardiovascular and lipid dysfunctions. These effects should be explored further for clinical applications.  相似文献   
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OBJECTIVE: To assess the diagnostic efficiency of positron emission tomography with 18-fluorine fluorodeoxyglucose in detecting breast cancer in augmented breasts. DESIGN: Retrospective study. SETTING: University hospital, Korea. SUBJECT: 9 cases or 8 patients with breasts augmented with paraffin or silicone. INTERVENTION: FDG-PET, mammography, and ultrasonography RESULTS: The mammogram detected the breast cancer in only 1 of 3 patients, and ultrasonography gave a false positive result in 1 patient with an augmented breast. In contrast, PET predicted all the cancers and 5/6 benign lesions. 2/3 breast cancers had axillary FDG uptake interpreted as showing metastatic involvement, and in 1 case with cancer with no axillary lymph node involvement there was no FDG uptake in the axilla, which correlated with the pathological finding. CONCLUSIONS: Although the high cost of PET makes its use as a screening test for all patients with augmented breasts unrealistic, it would be the best diagnostic choice if other methods failed.  相似文献   
19.

Background

The frequency of granular cell tumors (GCTs) identified in the gastrointestinal tract has recently increased with the increased use of routine endoscopy. Endoscopic treatment is increasingly used as an alternative to traditional surgical resection, but there are few reports on the efficacy, safety, and long-term prognosis of endoscopic treatment for GCTs. The aim of this study was to assess the efficacy, safety, and long-term prognosis of endoscopic resection for the gastrointestinal GCTs.

Methods

We examined a total of 27 GCTs in 25 patients who were treated by endoscopic resection from January 2007 to February 2011. For endoscopic resection, endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) was used.

Results

Twenty GCTs were located in the esophagus, 5 in the stomach, and 2 in the colon. The median size of the GCTs was 10 mm; the largest size, located in the ascending colon, measured 18 mm. EMR with a ligation device was performed in 20 cases, conventional EMR in 5 cases, and ESD in 2 cases. En bloc resection was performed in 25 cases (92.6 %), and endoscopic complete resection piecemeal resection was achieved in 25 cases (92.6 %). Pathologic complete resection was achieved in 22 lesions (81.5 %). Intraprocedural bleeding was noted in three patients, with no occurrence of perforation or postprocedure stricture. No recurrence was observed during the mean follow-up period of 15 months (range 9–31 months).

Conclusions

Endoscopic resection appears to be a safe and effective treatment for GCTs in the gastrointestinal tract.  相似文献   
20.

Objective

To evaluate the radiographic and MR appearance of idiopathic synovial osteochondromatosis of the hip.

Materials and Methods

Radiographs and MR images of 15 patients with idiopathic synovial osteochondromatosis of the hip were assessed. The former were analysed in terms of the presence of 1) juxta-articular calcified and/ or ossified bodies, 2) osteophytes, 3) bone erosion, 4) juxta-articular osteopenia, and 5) joint space narrowing, while for the latter, analysis focused on 1) the configuration of intra-articular bodies, 2) bone erosion, 3) synovial thickening, 4) conglomeration of intra-articular bodies, and 5) extra-articular extension.

Results

At hip radiography, juxta-articular calcified and/ or ossified bodies were seen in 12 of the 15 patients (80%), bone erosion in eight (53%), osteophytes in seven (47%), juxta-articular osteopenia in five (33%) and joint space narrowing in five (33%). In eight patients (53%), MR imaging depicted intra-articular bodies of focal low signal intensity at all pulse sequences, and areas of iso-intensity at T1WI and hyperintensity at T2WI. In three (20%), intra-articular bodies of focal low signal intensity and areas of hyperintensity at all pulse sequences were observed, with areas of iso-intensity at T1WI and hyperintensity at T2WI, while in four (27%), intra-articular bodies of only focal low signal intensity at all pulse sequences were apparent. Synovial thickening was present in 13 patients (87%), bone erosion in 11 (73%), conglomeration of the intra-articular bodies in 11 (73%), and an extra-articular herniation sac in six (40%).

Conclusion

The most common radiographic finding of synovial osteochondromatosis of the hip was the presence of juxta-articular calcified and/ or ossified bodies. MR imaging depicted intra-articular bodies of focal low signal intensity at all pulse sequences, with areas of iso-intensity at T1WI and hyperintensity at T2WI. In addition, the presence of an extra-articular herniation sac was not uncommon.  相似文献   
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