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961.
Comparative study of 1‐year clinical and radiological outcomes using robot‐assisted pedicle screw fixation and freehand technique in posterior lumbar interbody fusion: A prospective,randomized controlled trial 下载免费PDF全文
962.
在海蛰深加工中,采用热杀菌,当温度达到50℃以上时,海蛰就会变曲;采用紫外线杀菌,在高湿(60%以上)的环境中,杀菌效果急剧下降;采用化学药剂杀菌,又易引起药剂残留.通过对海蛰丝加工过程中采用臭氧水杀菌工艺的研究,克服了杀菌工艺的缺点和不足,为海蛰产品深加工提供了新的杀菌方法. 相似文献
963.
964.
Gastrin-releasing peptide-induced down-regulation of tumor suppressor protein PTEN (phosphatase and tensin homolog deleted on chromosome ten) in neuroblastomas 下载免费PDF全文
OBJECTIVES: To evaluate whether aggressive, undifferentiated neuroblastomas express tumor suppressor protein PTEN (phosphatase and tensin homolog deleted on chromosome ten) and to examine the effects of gastrin-releasing peptide (GRP) on PTEN gene and protein expression. SUMMARY BACKGROUND DATA: We have previously shown that neuroblastomas secrete GRP, which binds to its cell surface receptor (GRP-R) to stimulate cell growth in an autocrine fashion. However, the effects of GRP on expression of the tumor suppressor gene PTEN have not been elucidated in neuroblastomas. METHODS: Paraffin-embedded sections from human neuroblastomas were analyzed for PTEN and phospho-Akt protein expression by immunohistochemistry. Human neuroblastoma cell lines (SK-N-SH and SH-SY5Y) were stably transfected with the plasmid pEGFP-GRP-R to establish GRP-R overexpression cell lines, and the effects of GRP on PTEN gene and protein expression were determined. RESULTS: A decrease in the ratio of PTEN to phospho-Akt protein expression was identified in poorly differentiated neuroblastomas. An increase in GRP binding capacity was confirmed in GRP-R overexpressing cells, which demonstrated an accelerated constitutive cell growth rate. PTEN gene and protein expression was significantly decreased in GRP-R overexpressing cells when compared with controls. CONCLUSIONS: Our findings demonstrate decreased expression of the tumor suppressor protein PTEN in more aggressive undifferentiated neuroblastomas. An increase in GRP binding capacity, as a result of GRP-R overexpression, down-regulates PTEN expression. These findings suggest that an inhibition of the tumor suppressor gene PTEN may be an important regulatory mechanism involved in GRP-induced cell proliferation in neuroblastomas. 相似文献
965.
Kang Hee Shim Ji Eun Kwon Sung Gon Park Seol Ho Choo Se Joong Kim Sun Il Kim 《Urologic oncology》2021,39(5):298.e13-298.e20
BackgroundProgrammed death ligand-1 (PD-L1) expression in cancer is often associated with cancer aggressiveness and responsiveness to treatment with PD-1 pathway inhibitors. We conducted a systematic study on the expression of membranous PD-L1 (mPD-L1) and nuclear PD-1-L1 (nPD-L1) in prostate needle biopsy specimens of prostate cancer patients who underwent primary radiotherapy and analyzed the association between PD-L1 expression and clinicopathological characteristics and prognosis of patients.MethodA total of 971 cancer-containing prostate needle biopsy cores from 172 patients were immunohistochemically stained with anti-PD-L1 antibody. The association of PD-L1 expression with Gleason score and tumor volume percentage was evaluated for each biopsy core. Total of 171 patients were divided according to mPD-L1 or nPD-L1 expression, and clinicopathological characteristics were compared between the positive and negative groups. The prognostic significance of mPD-L1, nPD-L1 and common prognostic factors were analyzed in terms of biochemical recurrence.ResultTotal of 15% and 46% of biopsy cores were stained positive for mPD-L1 and nPD-L1, respectively. There was a positive correlation between Gleason score and mPD-L1 and a negative correlation between Gleason score and nPD-L1. Between mPD-L1 and nPD-L1, there was no significant correlation. There was intraindividual heterogeneity in PD-L1 expression among different Gleason scores. For mPD-L1, only pretreatment PSA was significantly higher in the positive group than in the negative, but not Gleason score and T stage. For nPD-L1, Gleason score and T stage were significantly higher in the positive group than in the negative. Both mPD-L1 and nPD-L1 expression were not predictive of BCR-free survival in univariate and multivariate analyses.ConclusionsOur results suggest that PD-1 pathway inhibitor may be a potential therapeutic option in high risk prostate cancer patients as early as neoadjuvant setting. The novel discovery of PD-L1 expression in the nucleus of PC should be subjected to further research. 相似文献
966.
目的 探讨再次手术切除与经皮射频消融在老年复发性小肝癌患者中的临床疗效。方法 回顾性分析2008 年1 月至2014 年1 月淮安第一医院收治的56 例肝癌术后以小肝癌形式复发的老年患者。其中再次手术切除治疗34例(手术切除组),经皮射频消融治疗22例(射频消融组)。比较两组的一般情况、术后生化指标、并发症发生情况以及生存状况,使用SPSS 20.0 统计学软件进行分析。结果 射频消融组患者治疗后TBIL、ALT、AST、ALB指标优于手术切除组(P<0.05);手术切除组患者并发症发生数(31例次)明显高于射频消融组(8 例次)( P<0.05)。射频消融组术后1、3、5 年无瘤生存率(86.4%、54.5%、45.5%)均明显好于手术切除组(61.8%、26.5%、14.7%),差异均有统计学意义(P<0.05)。结论 经皮射频消融对老年复发性小肝癌患者的远期治疗效果优于手术再切除,而且射频消融具有创伤小、肝功能影响小、术后并发症低等优点。 相似文献
967.
Son BH Kwak BS Kim JK Kim HJ Hong SJ Lee JS Hwang UK Yoon HS Ahn SH 《Archives of surgery (Chicago, Ill. : 1960)》2006,141(2):155-160
HYPOTHESIS: Breast cancer has become the most common cancer in Korean women in recent years, with continuously increased incidence rates attributed to westernized lifestyles. DESIGN: Retrospective case series evaluating the changing patterns of clinical characteristics in breast cancer during the last 15 years. SETTING: Hospitalized patients with breast cancer in a university medical center. PATIENTS: A total of 5001 breast cancer patients who underwent surgery between July 1989 and March 2004 at the Asan Medical Center. MAIN OUTCOME MEASURE: Clinicopathologic data were collected using the online Korea Breast Cancer Registration Program, including factors such as age, symptoms, stage, surgery, reconstruction, risk factors, and survival. RESULTS: The median age of patients slightly increased from 44 years in 1991 to 46 years in 2003. The most frequent age group was the fifth decade (41.7%) and premenopausal women younger than 50 years (64.9%). The proportion of asymptomatic patients detected by screening mammography increased from 3.8% in 1991 to 21.0% in 2003 (P<.001). The proportion of early breast cancer (stages 0 and I) increased from 34.2% in 1991 to 48.8% in 2003 (P=.013). Breast-conserving surgery has increased continuously from 5.1% in 1991 to 39.1% in 2003 (P<.001). Twelve percent of all patients who underwent mastectomies had immediate reconstruction, and the proportion showed an increasing trend, especially in skin-sparing mastectomy and transverse rectus abdominis myocutaneous flap reconstruction. Five-year observed survival rates were 84.1%. Five-year survival rates according to stages were as follows: (1) 98.5%, stage 0; (2) 95.3%, stage I; (3) 86.0%, stage II; (4) 65.0%, stage III; and (5) 29.3%, stage IV. The number of patients with specific risk factors, such as early menarche and late first delivery, significantly increased. Of 263 high-risk patients examined for the BRCA mutation, mutations were found in 20 patients (7.6%), with 13 cases with BRCA1 and 7 cases with BRCA2. CONCLUSIONS: The present study showed a continuous increase in the number of patients with breast cancer; the proportion of young patients, asymptomatic patients, early breast cancer, breast-conserving surgery, and immediate reconstruction after mastectomy; and the number of patients with risk factors. These results suggest that the clinical characteristics of Korean breast cancer patients reflect the patterns of Western countries. 相似文献
968.
Cho Rok Lee Haiyoung Son Sohee Lee Sang-Wook Kang Jong Ju Jeong Kee-Hyun Nam Woong Youn Chung Cheong Soo Park 《World journal of surgery》2014,38(4):872-877
Background
The present study was designed to investigate the necessity of completion thyroidectomy for patients who underwent thyroid lobectomy for low-risk papillary thyroid microcarcinoma (PTMC) that was later pathologically diagnosed as central lymph node (CLN) metastasis.Methods
Between 1986 and 2001, we assessed 551 patients who underwent thyroidectomy with prophylactic ipsilateral central compartment neck dissection, and 409 patients were followed-up completely. Thyroid lobectomy were performed in 281 and 128 patients, respectively. The patients were divided into two groups according to CLN metastasis. Clinicopathological profiles and follow-up details were investigated by retrospective chart review.Results
The CLN-positive and -negative groups were comprised of 43 (15.2 %) and 238 patients (84.8 %), respectively. The mean ages of the two groups were not significantly different (p > 0.05). The mean tumor size of the CLN-positive group (6.8 mm) was significantly larger than that of the CLN-negative group (5.6 mm; p < 0.05). Microscopic capsular invasion was significantly higher in the CLN-positive group (51.2 vs. 23.9 %; p < 0.05). Overall, 21 patients (7.4 %, 21/281) experienced recurrence. Among these, 2 (4.7 %, 2/43) and 19 (8.0 %, 19/238) were in the CLN-positive and -negative groups, respectively. There was no significant correlation between CLN metastasis and tumor recurrence.Conclusions
Postoperative recurrence was lower in the CLN-positive group, and there was no significant correlation between CLN metastasis and tumor recurrence. Our results suggest that it is not necessary to perform completion thyroidectomy for PTMC patients who have undergone thyroid lobectomy and who have been pathologically diagnosed with CLN metastasis. 相似文献969.
Hyoung Jin Kang Keon Hee Yoo Ji Won Lee Hyery Kim Soo Hyun Lee Ki Woong Sung Kyung Duk Park Hong Hoe Koo Hee Young Shin Hyo Seop Ahn 《Annals of hematology》2010,89(10):1035-1044
Umbilical cord blood transplantation (UCBT) with two units has been conducted with promising results in adults to overcome
the limitation of low cell numbers. In an attempt to improve the outcomes, double UCBT was performed in children and adolescents.
Sixty-one patients, including 44 acute leukemia, and 17 other hematologic diseases, received double UCBT. Donor-type engraftment
achieved in 82% of patients. Except one patient with persistent mixed chimerism of two units, other 49 patients showed dominancy
of one unit and only the CFU-GM was significant factor influencing dominancy. The event-free survival (EFS) of leukemia and
other hematologic disease were 59% and 53%, respectively, and the EFS of acute leukemia patients who received transplant in
first or second CR (68.6%) was significantly better than in those with advanced disease (22.2%) (P = 0.007). Among the factors influencing outcomes, low cell dose difference between two units (TNC difference/TNC of large
unit <15%) were associated with higher TRM, relapse, and lower EFS. Double UCBT was a promising modality of transplant in
children and adolescence. However, engraftment and other results were not so satisfactory yet. To improve the outcomes, development
of new selection guideline, probably including cell dose difference between two units and technology to enhance engraftment
and reduce transplantation-related mortality are warranted. 相似文献
970.