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991.
Annals of Nuclear Medicine - The objective of the present study was to develop a fully automated blood sampling system for kinetic analysis in mice positron emission tomography (PET) studies....  相似文献   
992.
Total body irradiation (TBI) using helical tomotherapy (HT) has advantages over the standard linear accelerator-based approach to the conditioning regimen for hematopoietic cell transplantation. However, the radiation field has to be divided into two independent irradiation plans to deliver a homogeneous dose to the whole body. A clinical target volume near the skin increases the skin surface dose; therefore, high- or low-dose regions arise depending on the set-up position accuracy because the two radiation fields are somewhat overlapped or separated. We aimed to determine an adequate treatment planning method robust to the set-up accuracy for the field joint dose distribution using HT-TBI. We calculated treatment plans reducing target volumes at the interface between the upper and lower body irradiations and evaluated these joint dose distributions via simulation and experimental studies. Target volumes used for the optimization calculation were reduced by 0, 0.5, 1.0, 2.0, 2.5, and 3.0 cm from the boundary surface on the upper and lower sides. Combined dose distributions with set-up error simulated by modifying coordinate positions were investigated to find the optimal planning method. In the ideal set-up position, the target volume without a gap area caused field junctional doses of up to approximately 200%; therefore, target volumes reduced by 2.0–3.0 cm could suppress the maximum dose to within 150%. However, with set-up error, high-dose areas exceeding 150% and low-dose areas below 100% were found with 2.0 and 3.0 cm target volume reduction. Using the dynamic jaw (DJ) system, dose deviations caused by set-up error reached approximately 20%, which is not suitable for HT-TBI. Moreover, these dose distributions can be easily adjusted when combined with the intensity modulation technique for field boundary regions. The results of a simulation and experimental study using a film dosimetry were almost identical, which indicated that reducing the target volume at the field boundary surface by 2.5 cm produces the most appropriate target definition.  相似文献   
993.
Clinical and Experimental Nephrology - Identifying predictive factors for coronavirus disease 2019 (COVID-19) is crucial for risk stratification and intervention. Kidney dysfunction contributes to...  相似文献   
994.
995.
Clinical and Experimental Nephrology - The number of patients aged ≥ 75 years and who need renal replacement therapy is steadily increasing. The study aimed to determine...  相似文献   
996.
Clinical and Experimental Nephrology - The management of congenital nephrotic syndrome of the Finnish type (CNF) is challenging. It is difficult to withdraw intravenous albumin infusions, resulting...  相似文献   
997.
BACKGROUND: Although no formal detailed definitions exist, a standard echocardiogram should easily be differentiated from a limited examination by its comprehensive nature and time requirement. OBJECTIVE: We evaluated the time required to perform each specific component of a comprehensive echocardiography examination and applied these data to compare the time required to complete 3 limited imaging protocols. METHODS: In all, 7 experienced sonographers were timed in their performance of a comprehensive echocardiographic examination on a healthy patient. A total of 3 limited imaging protocols were then constructed to evaluate for pericardial effusion, wall motion, and left ventricle size. The time necessary to complete each protocol was calculated by adding the average time required to perform all of its components and was compared with the comprehensive examination. RESULTS: The imaging time required to complete a standard study was 26 +/- 5.4 minutes (range: 20-32). The percentage of total study time spent on 2-dimensional imaging, M-mode, color Doppler, and spectral components was 31 +/- 2.9%, 11 +/- 3.6%, 17 +/- 2.9%, and 39 +/- 5.0%, respectively. The calculated time needed to perform a limited protocol was less than 5 minutes, resulting in a greater than 80% reduction in time compared with the standard examination. CONCLUSION: Time analysis of components of the standard echocardiography examination can be used to construct appropriate, time-efficient, limited, cardiac ultrasound imaging examinations and differentiate limited from comprehensive studies.  相似文献   
998.

Purpose

Our aim was to investigate whether exercise would ameliorate the impaired diaphragm muscle function and the inflammation induced by cigarette smoke solution (CSS) and endotoxin in rat lungs.

Methods

We induced inflammation using intratracheal injections of CSS plus endotoxin in rats. After 2 weeks (day 15), half of these rats (CSS-Run group) began daily treadmill exercise (CSS-Run group) and the other half remained sedentary (CSS group). A third group received intratracheal saline injections and remained sedentary (sham group). Injections continued for 28 days during the study period. To investigate inflammation in the lungs, respiratory function was evaluated and leukocytes were measured. Muscle tension was measured in diaphragm and skeletal muscles, and muscle morphology was histochemically assessed.

Results

Compared with the sham group, the inspiratory to expiratory ratios were significantly higher in the CSS group but not in the CSS-Run group. Treadmill exercise increased the percentage of circulating neutrophils. Histology of lungs from the CSS group and the CSS-Run group showed proliferating macrophages; however, aggregation and cell numbers were more remarkable in the CSS group. The peak diaphragm muscle twitch force was significantly higher in the CSS-Run group than in the sham group; additionally, the relative area of fast-twitch glycolytic fibers was more extensive (P < 0.01).

Conclusions

We demonstrated that 2 weeks of treadmill exercise improved airway resistance and diaphragm muscle contractile force in rats exposed to repetitive CSS plus endotoxin. We propose that local inflammation was attenuated by aerobic exercise, which increased diaphragm muscle contractility.
  相似文献   
999.

Purpose

The long-term outcomes of whole-breast and boost irradiation after breast-conserving surgery (BCS) for patients with breast cancer were retrospectively analyzed.

Materials and methods

Patients who received whole-breast and boost irradiation after BCS from 1990 to 2002 were included. Boost irradiation was administered to each tumor bed, regardless of the surgical margin status. The median doses of whole-breast and boost irradiation were 45 Gy in 25 fractions (range 36–45 Gy), and 14 Gy in 7 fractions (range 0–14 Gy), respectively.

Results

Data for 306 patients were analyzed. With a median follow-up time of 144 months, the 10-year overall survival, disease-free survival, ipsilateral breast tumor recurrence (IBTR), and metachronous contralateral breast cancer (MCBC) occurrence rates were 93.0, 84.1, 2.1, and 4.1 %, respectively. In the multivariate analysis, pT2 was a significant risk factor for IBTR (p = 0.041), while age ≤ 50 years and pT2 were significant risk factors for MCBC occurrence (p = 0.003 and 0.043, respectively). One patient (0.3 %) developed angiosarcoma in the irradiated region 120 months after the completion of radiation therapy.

Conclusion

The 12-year outcome of breast-conserving therapy using whole-breast and boost irradiation with doses of 45 and 14 Gy, respectively, was favorable.
  相似文献   
1000.

Objective

I-gel is a noncuff type of laryngeal airway mask. No horizontal line has yet been determined as an ideal position for pediatric sizes because of the variability in length of the oropharyngeal–laryngeal arch in children. We investigated whether there is a correlation between insertion length and patient body weight or height for the pediatric I-gel sizes from 1.5 to 2.5.

Methods

With parental informed consent, we planned to maintain the airway of 130 children aged from 7 months to 13 years by using the I-gel device under general anesthesia. The following two parameters were evaluated: (1) distance between the teeth and the connector wing; (2) insertion length (distance from the distal end of the gastric tube to the teeth). Size selection was determined on the basis of patients’ body weight. We identified the relationship between each parameter and height or weight.

Results

Average insertion length became gradually longer with increasing height and weight. Spearman’s R between insertion length and height or weight was 0.8. There was more correlation with height than with weight in pediatric size 2.5.

Conclusion

Results suggested that it is possible to draw an ideal line on the I-gel with sizes 1.5 and 2 only.
  相似文献   
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