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32.
Suzanne M. Jacques Faisal Qureshi Barbara J. Doss Adnan Munkarah 《Pediatric and developmental pathology》1998,1(5):380-387
Choriocarcinoma arising in the placenta, or intraplacental choriocarcinoma, has seldom been reported, particularly in the
absence of maternal metastases. Reluctance to diagnose choriocarcinoma in the presence of chorionic villi can delay diagnosis;
however, timely diagnosis of choriocarcinoma is prognostically important, both for the mother and infant. We report the clinicopathologic
findings in five mothers and infants in whom choriocarcinoma was identified in the placenta. None of the mothers had a history
of gestational trophoblastic disease in previous pregnancies. Three placentas were similar with a single small lesion grossly
suggesting a small infarct; microscopically these consisted of infarcted areas surrounded by choriocarcinoma. These three
mothers were unusual in that none had metastatic choriocarcinoma; two were treated with chemotherapy and remained disease-free;
the third was lost to follow-up shortly following delivery. The remaining two mothers had known pulmonary metastases at time
of delivery. One of these latter two placentas contained a large marginal lesion microscopically identified as choriocarcinoma.
The fifth placenta had rare microscopic foci of choriocarcinoma, and sheets of necrotic choriocarcinoma were identified in
“blood clot” submitted with the placenta. In four of the five cases the choriocarcinoma appeared to be arising from otherwise
normal chorionic villi, and in no case was there invasion of the villous stroma. All of the infants survived, and none had
evidence of choriocarcinoma. These cases support the concept that choriocarcinoma associated with otherwise normal pregnancy
arises in the placenta and may be more common than reported.
Received August 11, 1997; accepted December 8, 1997. 相似文献
33.
Cheong KL Roohi S Jarmin R Sagap I Tong SH Qureshi A 《The Medical journal of Malaysia》2000,55(4):464-466
Colonoscopy is an integral part of the clinician armamentarium in the diagnosis of colorectal cancer and its precursor, the adenoma. Polypoid lesions when identified can be excised at colonoscopy and in turn reduce the risk of colorectal cancer. We prospectively evaluated the yield of colorectal cancer and adenomatous polyps by indication for colonoscopy over a one-year period. A total of 375 colonoscopies were carried out. The more common indications of colonoscopy were rectal bleeding, abdominal pain, surveillance of colorectal cancer and altered bowel habit. The highest yield for cancer was for rectal bleeding with 12.5% while surveillance of patients with a history of polyps yielded the highest percentage of new polyps. We conclude that rectal bleeding as an indication for colonoscopy yielded the highest number of cancers. 相似文献
34.
Neural network analysis of clinicopathological and molecular markers in bladder cancer 总被引:2,自引:0,他引:2
PURPOSE: To evaluate retrospectively the ability of an artificial neural network (ANN) to predict bladder cancer recurrence within 6 months of diagnosis and stage progression in patients with Ta/T1 bladder cancer, and 12-month cancer-specific survival in patients with T2-T4 bladder cancer. MATERIALS AND METHODS: Data were analyzed using a NeuralWorks Professional II/Plus software package. The input neural data consisted of clinicopathological and molecular characteristics. Distinct patient groups were used for the prediction of stage progression and tumor recurrence in Ta/T1 bladder cancers, and 12-month cancer-specific survival for patients with T2-T4 tumors. ANN predictions were compared with those of four consultant urologists. RESULTS: The accuracy of the neural network in predicting stage progression and recurrence within 6 months for Ta/T1 tumors and 12-month cancer-specific survival for T2-T4 cancers was 80%, 75% and 82% respectively; with corresponding figures for clinicians being 74%, 79% and 65%. On restricting the validation subset to patients with T1G3 tumors in relation to stage progression, the sensitivity of the ANN analysis increased to 100% with a specificity of 78% and an overall accuracy of 82%. The performance of the ANN in predicting stage progression in T1G3 tumors was significantly higher than that of clinicians (p = 0.25 for the ANN and p = 0.008 for clinicians, McNemar test). CONCLUSIONS: Data analysis using an ANN has been shown to be a useful adjunct in predicting outcomes in patients with bladder cancer and out-performs clinicians' predictions of stage progression in the high risk group of patients with T1G3 disease. 相似文献
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IntroductionThe majority of dental procedures need local anesthesia for pain control, and lidocaine/ lignocaine is the most commonly used anesthetic agent in dentistry. Although effective and safest, the anesthetic agent still has some complications. To overcome these many alternatives have been used. Tramadol has been shown to have some local anesthetic (LA) effects when used for infiltration anesthesia in dentistry.MethodsIn the present study, the local anesthetic efficacy of tramadol was compared with 2% lignocaine containing 1: 100,000 adrenaline for the extraction of maxillary fully erupted 3rd molar teeth. The parameters recorded included the onset of action, duration of action, intraoperative pain, post-operative analgesic effect, and incidence of an allergic reaction. A total of 200 patients were randomly divided into two groups. In group A -Each patient received 0.6 ml of 5% tramadol (Tramataj- 50 mg prepared by Taj pharma company) 0.4 ml buccally and 0.2 ml palatally for extraction of maxillary 3rd molar as local infiltration following strict aseptic precaution. In Group B- patients received 0.6 ml of 2% lignocaine containing 1: 100,000 adrenaline buccally and 0.2 ml palatally as infiltrations.ResultsIt was found that 5% tramadol has a local anesthetic efficacy similar to 2% lignocaine with adrenaline but was found to be a comparatively weaker agent.Conclusiontramadol is a valid alternative for performing extractions in normal patients or patients allergic to lidocaine. 相似文献
38.
Rahat Ullah Yuan Qiang Jawad Ahmad Nikolai Ivanovich Vatin Mohammed A. El-Shorbagy 《Materials》2022,15(12)
The interest of researchers in UHPC has increased over the past decade. It is crucial to understand the structural behavior of reinforced UHPC (R/UHPC) components under various loading conditions before they can be used as a replacement for conventional concrete. Although several studies on ultra-high-performance concrete (UHPC) have been conducted, the knowledge is scattered, and no one can easily judge the performance and methodology of UPHC. Therefore, the purpose of this study was to review the research studies already carried out on UHPC. The review focuses on the materials’ physical and chemical composition, mechanical and durability characteristics, fire resistance, and environmental benefits of UHPC. Design considerations for effectively utilizing UHPC in structural elements are also presented. The best UHPFRC mixture is obtainable with a steel fiber content of 2–3% and a water-to-cement ratio of 0.2–0.3. The review also discusses the essentials recommendation for future research on UHPC. 相似文献
39.
Rena C. Moon Vincent Kirkpatrick Lori Gaskins Andre F. Teixeira Muhammad A. Jawad 《Surgery for obesity and related diseases》2019,15(2):245-252
Background
Biliopancreatic diversion with duodenal switch (DS) is known to be superior in weight loss to other bariatric procedures, but with the disadvantage of increased complication rates. Single-anastomosis duodenal-ileal bypass (SADI-S) is reported to have similar weight loss with lower complication rates compared with traditional DS.Objectives
The aim of this study was to compare weight loss and complication rate between SADI-S and double-anastomosis DS at a single institution.Setting
Academic hospital, United States.Methods
A retrospective chart review was performed on 185 patients who underwent laparoscopic or robot-assisted laparoscopic DS between March 1, 2015 and December 10, 2017. A total of 111 patients had SADI-S, and 74 patients underwent double-anastomosis DS.Results
Baseline patient characteristics were comparable between the 2 groups. The mean preoperative body mass index was 56.3 kg/m2 and 54.4 kg/m2 in SADI-S and double-anastomosis DS patients, respectively. Thirteen (11.7%) and 4 (5.4%) patients were readmitted within 30 days after SADI-S and double-anastomosis DS, respectively (P?=?.16). Percentage of total weight loss was 22.0%, 38.5%, and 44.2% in the SADI-S group and 20.2%, 38.0%, and 48.4% in the double-anastomosis DS group at 6, 12, and 24 months, respectively. The majority of patients had vitamin A and E levels in the normal range. However, 40% to 60% of the patients had low levels of vitamin D after the procedure.Conclusions
SADI-S and double-anastomosis DS are comparable in terms of weight loss and complication rate. However, close nutritional follow-up is warranted for both procedures. 相似文献40.
Jawad H. Butt Nikolaj Ihlemann Ole De Backer Lars Søndergaard Eva Havers-Borgersen Gunnar H. Gislason Christian Torp-Pedersen Lars Køber Emil L. Fosbøl 《Journal of the American College of Cardiology》2019,73(13):1646-1655