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991.
992.
Maddox M Pareek G Al Ekish S Thavaseelan S Mehta A Mangray S Haleblian G 《Journal of endourology / Endourological Society》2012,26(10):1367-1371
Abstract Background and Purpose: While the power needed to initiate bipolar vaporization is higher than conventional monopolar resection, the energy needed to maintain bipolar vaporization is significantly lower and may result in less thermal tissue injury. This may have implications for hemostasis, scarring, and perioperative morbidity. The objective of this study is to assess histopathologic changes in prostatic tissue after bipolar transurethral vaporization of the prostate. Patients and Methods: Male patients older than 40 years with a diagnosis of benign prostatic hyperplasia (BPH) who elected to undergo bipolar transurethral vaporization of the prostate were included in this study. Patients were excluded if they had a previous transurethral resection of the prostate (TURP) or prostate radiation therapy. An Olympus button vaporization electrode was used to vaporize prostate tissue. A loop electrode was then used to obtain a deep resection specimen. The vaporized and loop resection surfaces were inked and sent for pathologic analysis to determine the presence of gross histologic changes and the depth of penetration of the bipolar vaporization current. Results: A total of 12 men underwent bipolar TURP at standard settings of 290?W cutting and 145?W coagulation current. Mean patient age was 70±10.2 years (range 56-88 years). Mean surgical time was 48.7±20.2 minutes (range 30-89?min). Mean depth of thermal injury was 2.4±0.84?mm (range 0.3-3.5?mm). Histopathologic evaluation demonstrated thermal injury in all specimens, but no gross char was encountered. Conclusions: In bipolar systems, resection takes place at much lower peak voltages and temperatures compared with monopolar systems. Theoretically, this leads to less collateral thermal damage and tissue char. Our tissue study illustrates that the button vaporization electrode achieves a much larger depth of penetration than previous studies of bipolar TURP. This may be because thermal injury represents a gradual continuum of histologic changes. 相似文献
993.
Shadi Beshai Jennifer L. Prentice Keith S. Dobson Katarzyna Nicpon 《Cognitive therapy and research》2014,38(6):621-633
The modified selective attention hypothesis proposes that individuals showing signs of depression will fail to disengage from negative stimuli in the environment. Some research suggests that depressive symptoms decrease once this bias is “corrected”. Thus, attention may play a causal and/or sustaining role in depression. The present study examined whether (a) attention can be modified in a student sample to induce a negative attentional bias; and (b) this trained attentional bias will be associated with negative shifts in mood and cognitions. A sample of undergraduates (N = 112) were recruited and asked to complete questionnaires designed to measure depressive symptoms, mood, and negative thoughts toward the self. Participants were then randomly assigned to either an attend-negative (n = 60) or a no-training control condition (n = 52), and asked to complete a computer task. In the attend-negative condition, the computer task (dot probe) was designed to elicit a transient attentional bias toward negative stimuli. After the completion of this task, participants completed the questionnaires a second time. Participants in the experimental condition evidenced higher negative attentional bias scores in comparison to control participants. Further, females demonstrated more negative attention at the end of the training relative to males. Repeated measures analysis of variances further found that following the completion of the computer task, both groups evidenced a negative shift in mood. These results must be interpreted with caution given that baseline attentional biases were not measured in this study. Replication and extension of the findings of this study is necessary. 相似文献
994.
S. Gehrmann M. Barakat M. Hakimi Dr. Jan Grassmann A. Schädle J. Windolf 《Obere Extremit?t》2012,7(4):189-193
Distal radius fractures can cause wrist motion deficits. The purpose of this study was a motion analysis of the wrists in patients after complete fracture union and rehabilitation. A total of 28 patients with healed unilateral intra-articular distal radius fractures performed multiple circumferential motions of the wrist. Global wrist motion was captured by motion analysis based on electrogoniometry. All participants exhibited a low DASH score (16.7). The maximum motion boundaries of the wrists were reconstructed with a custom-made MatLab program. Maximum flexion-extension (FE), radial-ulnar deviation (RUD) and the area were calculated from the circumduction of the motion envelope. Differences between the fractured wrist and the unimpaired side were compared and analyzed with Student?s t-test. The circumduction boundaries of the wrists showed the typical kidney-shaped configuration with an oblique axis from radial/extension to ulnar/flexion. Compared to the uninjured side, a significant motion deficit was found for the orthogonal directions (FE, RUD) and the areas of the motion envelope (p?<?0.01). The results demonstrate that motion deficits can persist after complete union and rehabilitation of fractured wrists which can remain unidentified by manual methods of goniometry. 相似文献
995.
Patterson CA Barakat LP Henderson PK Nall F Westin A Dampier CD Hsu LL 《Journal of pediatric hematology/oncology》2011,33(1):4-9
Communicating risk is an important activity in medical decision-making; yet, numeracy is not a universal skill among the American public. We examined the hypothesis that numerical risk information about the use of hydroxyurea for children with sickle cell disease would elicit different risk assessment responses when visual depictions were used instead of abstract numbers and depending on the disease severity. Parents of 81 children with sickle cell disease participated in a survey in which hydroxyurea was first described as carrying a certain chance of risk for both birth defects and cancer. Then, the parents indicated the highest risk at which they would hypothetically consent to the treatment to help their child. Risk presentations were repeated with abstract numerical, pie graph, and 1000 people histogram formats. The χ analyses comparing high-risk to low-risk assessment across presentation formats showed high consistency between visual depictions but low consistency of abstract numerical with visual depictions. The parents of children with SC and other less severe types of SCD were less willing to accept higher risk than those with SS when the data were presented numerically. Given earlier concerns about poor "numeracy" in the US population, visual depictions of risk could be an effective tool for routine communication in health education and medical decision-making. 相似文献
996.
997.
Shih KK Garg K Levine DA Kauff ND Abu-Rustum NR Soslow RA Barakat RR 《Gynecologic oncology》2011,123(1):88-94
Background
The hereditary basis of endometrial cancer is apparent in young women with endometrial cancer. The objective of this study was to examine risk factors and outcomes in patients 40 years of age and younger with endometrial cancer.Methods
We performed a retrospective cohort study of patients aged 40 years or less who were diagnosed with endometrial carcinoma between 1/93 and 5/08. Clinical and pathologic data were extracted from medical records. Paraffin-embedded slides from hysterectomy specimens were obtained and DNA mismatch repair (MMR) immunohistochemistry was performed. Cases were analyzed according to the presence of DNA MMR protein defects. Standard two-sided statistical tests were performed.Results
Of the 56 identified patients, the median age was 36 years (range, 24–40). The majority of the endometrial carcinomas were of endometrioid histology (91%), stage I (71%), and FIGO grade 1 (59%). Abnormal DNA MMR was found in 9 cases (16%). Cases with abnormal DNA MMR had lower body mass index (BMI) (P = 0.05), and had a family history suggestive of Lynch syndrome (P = 0.001). Tumors were more likely to have advanced stage disease (P < 0.001), be high grade (P < 0.001), have deep myometrial invasion (P < 0.001), and have lymphovascular invasion (P = 0.002). Cases with abnormal DNA MMR had significantly worse overall survival (P = 0.028) and progression-free survival (P = 0.042).Conclusions
Endometrial cancer is rare in women aged 40 years or less. In this group of patients, loss of DNA MMR was associated with lower BMI, worse clinicopathologic factors, and worse outcome. These results may have implications when young women diagnosed with endometrial cancer are counseled regarding prognosis. 相似文献998.
Shih KK Zhou Q Huh J Morgan JC Iasonos A Aghajanian C Chi DS Barakat RR Abu-Rustum NR 《Gynecologic oncology》2011,120(3):480-484
Objective
The objective of this study was to identify clinicopathologic features that are associated with an increased risk of recurrence for borderline ovarian tumors (BOT).Methods
We performed a retrospective review of all patients treated for BOT at our institution from 1979 to 2008. Progression-free survival (PFS) was defined as the time of diagnosis to time of recurrence/death or last follow-up. The Kaplan-Meier method was used to calculate the PFS rate and the Wilcoxon-Gehan test was performed to identify prognostic factors.Results
A total of 266 patients were identified. The median age was 43 years (range, 15-94 years). The majority of patients (68.4%) had FIGO stage I disease and serous histology (73.7%). Only 23 (8.6%) patients developed recurrent disease. The median PFS was 19 years and the median follow-up was 4 years. Abnormal baseline CA-125 (> 35 U/ml), advanced stage, age at diagnosis, and invasive implants were associated with decreased PFS. Of the 196 patients with serous BOT, those with a micropapillary pattern had a 3-year PFS of 75.9% (95%CI, 55.6-87.8) compared with 94.3% (95% CI, 88.4-97.3) for patients without micropapillary pattern (P < 0.001).Conclusion
Age at diagnosis, an elevated preoperative CA-125, invasive implants, and micropapillary histology were clinical factors associated with increased risk of recurrence in women with BOT. Including these clinicopathologic features will likely identify patients at higher risk for recurrence, for whom development of new treatment strategies would be appropriate. 相似文献999.
Objective
The objective of this study was to determine the incidence of invasive cancer in ovarian masses diagnosed as borderline tumor (BT) at the time of frozen section.Methods
We performed a retrospective review of all patients diagnosed with ovarian BT on frozen section (FS) at our institution between 2000 and 2010. Clinical and pathologic data were extracted. Univariate and multivariate analyses were performed using standard two-sided statistical tests.Results
A total of 120 patients were identified, of which 104 (86.7%) had BT on frozen section that was confirmed on final pathology. In 15 (12.5%) patients, BT was diagnosed on FS but was reclassified as invasive cancer on final pathology. One patient (0.8%) had BT on FS but benign pathology on final diagnosis. Histologies included serous in 79 (65.8%), seromucinous in 13 (10.8%), mucinous in 21 (17.5), endometrioid in 5 (4.2%), and clear cell in 2 (1.7%) patients. Reclassification of pathologic diagnosis was related to histologic subtype, but only for endometrioid and clear cell tumors (P < 0.001). The rate of invasive cancer for serous micropapillary tumors on frozen section was 42.8% compared with 2.8% for serous non-micropapillary tumors (P < 0.001). Tumor size > 8 cm was associated with a 22.4% incidence of invasive cancer on final pathology compared to 3.2% in tumors ≤ 8 cm (P = 0.004).Conclusion
Comprehensive surgical staging can be considered in BT > 8 cm in diameter, as well as those with micropapillary serous, endometrioid, and clear cell histology diagnosed at the time of frozen section analysis. 相似文献1000.