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91.
To obtain baseline data for cervical cancer prevention in Japan, we analyzed human papillomavirus (HPV) data from 5045 Japanese women aged less than 40 years and diagnosed with cervical abnormalities at 21 hospitals during 2012‐2017. These included cervical intraepithelial neoplasia grade 1 (CIN1, n = 573), CIN2‐3 (n = 3219), adenocarcinoma in situ (AIS, n = 123), and invasive cervical cancer (ICC, n = 1130). The Roche Linear Array was used for HPV genotyping. The HPV type‐specific relative contributions (RCs) were estimated by adding multiple infections to single types in accordance with proportional weighting attributions. Based on the comparison of type‐specific RCs between CIN1 and CIN2‐3/AIS/ICC (CIN2+), RC ratios were calculated to estimate type‐specific risks for progression to CIN2+. Human papillomavirus DNA was detected in 85.5% of CIN1, 95.7% of CIN2‐3/AIS, and 91.2% of ICC. Multiple infections decreased with disease severity: 42.9% in CIN1, 40.4% in CIN2‐3/AIS, and 23.7% in ICC (P < .0001). The relative risk for progression to CIN2+ was highest for HPV16 (RC ratio 3.78, 95% confidence interval [CI] 3.01‐4.98), followed by HPV31 (2.51, 1.54‐5.24), HPV18 (2.43, 1.59‐4.32), HPV35 (1.56, 0.43‐8.36), HPV33 (1.01, 0.49‐3.31), HPV52 (0.99, 0.76‐1.33), and HPV58 (0.97, 0.75‐1.32). The relative risk of disease progression was 1.87 (95% CI, 1.71‐2.05) for HPV16/18/31/33/35/45/52/58, but only 0.17 (95% CI, 0.14‐0.22) for HPV39/51/56/59/66/68. Human papillomavirus 16/18/31/33/45/52/58/6/11 included in a 9‐valent vaccine contributed to 89.7% (95% CI, 88.7‐90.7) of CIN2‐3/AIS and 93.8% (95% CI, 92.4‐95.3) of ICC. In conclusion, our data support the Japanese guidelines that recommend discriminating HPV16/18/31/33/35/45/52/58 genotypes for CIN management. The 9‐valent vaccine is estimated to provide over 90% protection against ICC in young Japanese women.  相似文献   
92.
Neoadjuvant chemotherapy (NAC) is a standard regimen in treatment of breast cancer patients, but some are resistant to NAC. We hypothesized that breast cancer cells overexpressing epithelial cell adhesion molecule (EpCAM) could be resistant to NAC, contributing to a poor prognosis. Seventy patients with breast cancer were treated with NAC. Core needle biopsy (CNB) specimens and resected tumors before and after NAC, respectively, were examined for expression of EpCAM. In resected tumors, high EpCAM expression correlated with lymphovascular invasion status and nuclear grade (P = 0.01 and 0.008, respectively), and was associated with poor pathological and clinical responses (P < 0.001). High tumoral EpCAM expression in resected tumor was independently related to a poor pathological response. Patients with high EpCAM expression before and after NAC (high‐to‐high group) showed worse pathological and clinical responses (P = 0.008 and <0.001, respectively) than the patients with high and low EpCAM expression before and after NAC, respectively (high‐to‐low group). The overall survival rate of the high‐to‐high group appeared shorter compared with the high‐to low‐group (P = 0.049). Our findings imply that higher levels of EpCAM in breast cancer may be associated with poor response to NAC via a potential chemoresistant effect.  相似文献   
93.
OBJECTIVE: To evaluate the performance of 40-detector row computed tomography (CT) in the detection of in-stent stenosis of coronary stents. METHODS: Seven patent vascular models, 7 stenotic models, and 7 obstructed models were scanned with a 40-detector CT. We made the vascular models using 3 types of stent (Bx-Velocity, Express2, Driver) with an inner diameter of about 2.5, 3.0, or 3.5 mm. We measured the stent lumen diameter and evaluated the in-stent stenosis visually for the 21 vascular models. We evaluated attenuation values of the stent lumen of the 9 patent models of 2.5-mm diameter. RESULTS: The inner diameters of the vascular models were underestimated by CT with mean measurement errors of -1.19 to -1.49 mm. The absolute mean overall measurement error decreased as the inner diameter increased. The direct visualization of in-stent stenosis was possible for the 3.0- and 3.5-mm diameter models, but impossible for the 2.5-mm diameter models. For patent vascular models of 2.5-mm diameter, the CT attenuation inside the stent was significantly higher than that of the unstented portion (P < 0.0001). For obstructed vascular models of 2.5-mm diameter, the CT attenuation inside the stent was significantly lower than that of the unstented portion (P < 0.0001). Also for stenotic vascular models of 2.5-mm diameter, the CT attenuation inside the stent was lower than that of the unstented portion. CONCLUSIONS: Visualization of stent lumen on CT is affected by the stent diameter. Measurement of stent lumen is useful for detection of in-stent stenosis, when the direct visualization of in-stent stenosis is impossible.  相似文献   
94.

Introduction

Breast cancer incidence increases from the age of 30 years. As this age range coincides with that in which women usually pursue pregnancy, undergoing medical examinations for conditions such as breast cancer is a concern, especially when pregnancy is uncertain during the first eight weeks. Moreover, in this age range, breast often exhibits a high density, thus compromising diagnosis. For such density, digital breast tomosynthesis (DBT) provides a more accurate diagnosis than 2D mammography given its higher sensitivity and specificity. However, radiation exposure increases during DBT, and it should be determined.

Methods

We determined the entrance surface dose, scattered radiation dose, and average glandular dose (AGD), which can be mutually compared following an international protocol. Using our proposed method, the distribution of scattered radiation can be easily and quickly obtained with a minor load to the equipment. Then, we can determine the indoor scattered radiation and surface dose on patients during DBT.

Results

We obtained a maximum AGD of 2.32 mGy. The scattered radiation was distributed over both sides with maximum of approximately 40 μGy, whereas the maximum dose around the eye was approximately 10 μGy.

Conclusion

By measuring doses using the proposed method, a correct dose information can be provided for patients to mitigate their concerns about radiation exposure. Although the obtained doses were low, their proper management is still required. Overall, the results from this study can help to enhance dose management for patients and safety management regarding indoor radiation.  相似文献   
95.
BACKGROUND: DISC1 has been suggested as a causative gene for psychoses in a large Scottish family. We recently identified FEZ1 as an interacting partner for DISC1. To investigate the role of FEZ1 in schizophrenia and bipolar disorder, case-control association analyses were conducted in Japanese cohorts. METHODS: We performed a mutation screen of the FEZ1 gene and detected 15 polymorphisms. Additional data on informative polymorphisms were obtained from public databases. Eight single nucleotide polymorphisms (SNPs) were analyzed in 119 bipolar disorder and 360 schizophrenic patients and age- and gender-matched control subjects. All genotypes were determined with the TaqMan assay, and selected samples were confirmed by sequencing. RESULTS: The two adjacent polymorphisms displayed a nominally significant association with schizophrenia (IVS2+ 1587G>A, p = .014; 396T相似文献   
96.
BACKGROUND: The neurobiological basis for autism remains poorly understood. Given the role of growth factors in brain development, we hypothesized that epidermal growth factor (EGF) may play a role in the pathophysiology of autism. In this study, we examined whether serum levels of EGF are altered in adult subjects with high-functioning autism. METHODS: We measured serum levels of EGF in the 17 male subjects with high-functioning autism and 18 age-matched healthy male subjects. RESULTS: The serum levels of EGF in the subjects with high-functioning autism (72.4 +/- 102.8 pg/mL [mean +/- SD]) were significantly lower (Mann-Whitney U = 22.0, p < .001) than those of normal control subjects (322.3 +/- 122.0 pg/mL [mean +/- SD]). However, there were no correlations between serum EGF levels and clinical variables in the subjects with autism. CONCLUSIONS: This study suggests that decreased levels of EGF might be implicated in the pathophysiology of high-functioning autism.  相似文献   
97.
We developed a novel method for enhancing light-microscopic visualization of pancreatic zymogen granules in a selective manner on hematoxylin and eosin-stained sections. By using an absorption filter that transmits light with wavelength from 510 to 550 nm, corresponding to the narrow absorption spectrum of eosin, only eosinophilic tissue and cellular components were remarkably highlighted as distinct shadows against lighter background consisting of basophilic components. Using a pair of mirror sections of the pancreas, immunocytochemistry with anti-amylase antibody confirmed that the shadows observed through the filter represented zymogen granules. Immersion in formalin for 36 h at room temperature was the optimal fixation condition. Here we designate the procedure as the “eosin-shadow method” and propose that this technique is convenient and useful to help investigators identify zymogen granules more easily in routine pathological examination and histological studies.  相似文献   
98.
99.
BACKGROUND: Hepatic stellate cells have been reported to play important roles in the regulation of hepatic microcirculation via cell contraction. Increase in intracellular calcium concentration is required to induce cell contraction. We have already reported the existence of L-type voltage-operated Ca2+ channels (VOCC), such as smooth muscle cells. On the other hand, alcohol has been known to disturb hepatic microcirculation. In this study, we evaluated the effect of acute and chronic treatment of alcohol on VOCC in rat hepatic stellate cells. METHODS: Stellate cells isolated from rats were cultured with or without 100 mM ethanol for up to 14 days. VOCC were detected by the patch clamp technique. Cells cultured for 14 days without ethanol were exposed to ethanol to investigate calcium current during membrane depolarization. alpha-Smooth muscle actin (alpha-SMA) was stained by indirect immunofluorescence. RESULTS: In the control model, VOCC were recognized in cells cultured for more than 7 days. Detection of VOCC increased from 9% on day 7 to 55% on day 14. On the other hand, VOCC in cells treated chronically with 100 mM ethanol appeared earlier than in the control and the incidences were significantly higher than those of the control accompanied with an early activation of cells. In contrast, simultaneous exposure to ethanol during the membrane depolarization inhibited Ca2+ current. CONCLUSIONS: The expression of Ca2+ channels in stellate cells were up-regulated by the chronic treatment of alcohol accompanied with the transformation to myofibroblast-like phenotype. However, alcohol itself inhibited Ca2+ current.  相似文献   
100.
Sentinel lymph node biopsy (SLNB) is standard care for patients with early-stage breast cancer, and axillary lymph node dissection (ALND) is considered unnecessary when sentinel lymph nodes (SLNs) are tumor-free. Additional non-SLN metastasis in patients with positive SLNs can be estimated using several risk factors such as primary tumor size, metastatic tumor size in SLNs, lymphatic vessel invasion, and so on. All patients with positive SLNs may be treated with further ALND based on their own risk for non-SLN metastasis. Recent randomized clinical trials have already proved less surgical morbidity and better QOL for SLNB alone compared with ALND. However, trials concerning the efficacy of ALND in positive SLNB patients in preventing local regional recurrence and improving overall survival compared with no ALND, and also, concerning the effectiveness of ALND compared with axillary radiation therapy (RT), have not yielded clear results. The prognostic significance of micrometastasis in SLNs or bone marrow also remains to be determined. So far SLNB is not acceptable for patients with positive nodes in the axilla at initial diagnosis even if their axillary metastases are down-staged to negative by neoadjuvant chemotherapy. Although basically SLNB does not need to be performed for patients with pure ductal carcinoma in situ (DCIS), it is recommended for patients with an initial diagnosis of DCIS which is large, palpable, high grade, or found in younger patients. Because these types of DCIS have higher incidences of accompanying invasive lesions. In addition if patients will undergo mastectomy, SLNB is recommended because of the inability to perform SLNB after mastectomy. SLNB may be acceptable for patients with T3 or T4b tumors, even though SLN identification is lower yet SLN involvement is higher compared with T1 or T2 tumors, and systemic adjuvant therapy is more important for patients with T3 or T4b tumors. SLNB is a bridge to further axillary treatment such as ALND or axillary RT, and which strategy, including no further treatment, is best considered individually based on recurrence risk, treatment responsiveness and use or non-use of systemic therapy.  相似文献   
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