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91.
EV Loftus Jr BA Olivares-Pakzad KP Batts MC Adkins DH Stephens MG Sarr EP DiMagno 《Gastroenterology》1996,110(6):1909-1918
BACKGROUND & AIMS: Intraductal papillary-mucinous tumor (IPMT) of the pancreatic ducts is increasingly recognized. This study investigated if clinical, imaging, or, histological features predicated outcome, formulated a treatment algorithm, and clarified relationships among IPMT, mucinous cystic neoplasms of the pancreas (MCN), and chronic pancreatitis. METHODS: The medical records, radiographs, and pathological specimens of 15 patients with IPMT (dilated main pancreatic duct or branch ducts with mucin overproduction) who were evaluated between October 1983 and January 1994 were reviewed. RESULTS: One patient had hepatic metastases. Fourteen underwent an operation (6 distal pancreatectomy, 4 total pancreatectomy, and 4 pancreaticoduodenectomy); all had dysplastic intraductal epithelium and chronic pancreatitis, whereas 3 had invasive adenocarcinoma. After a median of 25 months, 10 patients were alive; 3 of 4 with malignant and 2 of 11 with benign IPMT died (P < 0.05). Patients with or without carcinoma had similar clinical and radiographic features. A clinical diagnosis of chronic pancreatitis had been made in 9 patients with benign IMPT and in none with malignant IPMT (P < 0.05). CONCLUSIONS: IPMT is a dysplastic and likely precancerous lesion that is frequently diagnosed as chronic pancreatitis and is separate from MCN. Because it is not possible to distinguish noninvasive from invasive IPMT preoperatively, complete surgical excision of the dysplastic process is our treatment of choice whenever appropriate. (Gastroenterology 1996 Jun;110(6):1909-18) 相似文献
92.
Human platelet lysates contained potent mitogenic activities for MCF-7 human breast-cancer cells in serum-free-defined media. Because these activities were not replaced by known platelet mitogens, such as platelet-derived growth factor or transforming growth factor beta, we sought to identify the breast cancer cell mitogens by purification and N alpha amino-acid sequencing. Acetic acid extracts of outdated human platelets were concentrated by ammonium sulfate precipitation and fractionated on Sephadex G-50 and Bio-Gel P-10 columns in 0.5 mol/L acetic acid. Two major activities were resolved by molecular sieve methods and fractionated further by reverse-phase high-performance liquid chromatography (HPLC). Purifications (70,000 to 870,000-fold) were accomplished yielding mol wt 7,400 products that were homogeneous as determined by iodination, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and autoradiography. The factors were identified as insulinlike growth factor I (IGF-I) and II (IGF-II) and truncated IGF-I by N alpha amino acid microsequencing. In dose-response experiments, platelet-derived IGF-I and IGF-II promoted multiple divisions of the MCF-7 cells with ED50 values of 12 and 100 pg/mL, respectively. The specific activities and other bioassay characteristics of platelet-derived IGF-I and IGF-II were similar to those of recombinant-produced human growth factors. This is the first report of the purification of insulinlike growth factors from human platelet lysates. 相似文献
93.
Hydroxyurea (HU), an inhibitor of DNA synthesis, has been shown to increase fetal hemoglobin (HbF) levels in patients with sickle cell anemia and in some patients with beta-thalassemia. However, until now there have not been good in vitro model systems that simulate this effect for study of the molecular and cellular mechanism(s) involved in perturbing the normal ontogeny of the globin genes. We analyzed the cellular effects of HU using a two-phase liquid culture procedure (Fibach et al: Blood 73:100, 1989) in which human peripheral blood- derived progenitor cells undergo proliferation and differentiation. HU was found to have multiple effects on these cultured cells: (1) an increase in the proportion of HbF produced; (2) a decrease in cell number due to inhibition of cell proliferation; (3) an increase in hemoglobin content per cell (mean corpuscular hemoglobin [MCH]); and (4) an increase in cell size (mean corpuscular volume). The extent of these effects was related to the HU dose and time of addition. When added to cell cultures from normal individuals, 4 days following their exposure to erythropoietin (EPO), 100 mumol/L HU caused a 1.3- to 3.5- fold increase in the proportion of HbF, from 0.4% to 5.2% (mean 1.6) in untreated to 1.5% to 8.2% (mean 3.1) in HU-treated cultures and a 45% +/- 10% increase in MCH but only a 25% +/- 7% decrease in cell number on day 13. Cultures of cells derived from five patients with sickle cell anemia have shown a twofold to fivefold increase in the percentage of Hb F following addition of HU while four patients with beta- thalassemia showed a 1.3- to 6.2-fold increase. We believe that this primary cell culture procedure should prove useful in studying the cellular and molecular mechanisms of pharmacologic induction of HbF and might provide a valuable predictive assay system for evaluation of the response of individual patients with hemoglobinopathies to HU and similar agents. 相似文献
94.
Ayesha Karim Ahmad Sebastiana Atzori James Maurice Simon D Taylor-Robinson Adrian KP Lim 《World journal of hepatology》2020,12(11):1055-1066
BACKGROUNDPortal hypertension is a major complication of cirrhosis that is associated with significant morbidity and mortality. The present gold-standard method to risk stratify and observe cirrhosis patients with portal hypertension is hepatic venous pressure gradient measurement or esophagogastroduodenoscopy. However, these methods are invasive, carry a risk of complications and are associated with significant patient discomfort. Therefore, non-invasive splenic parameters are of clinical interest as potential useful markers in determining the presence of portal hypertension. However, diagnostic accuracy and reproducibility remains unvalidated.AIMTo assess the diagnostic accuracy of spleen stiffness, area and diameter in predicting the presence of portal hypertension.METHODSOf 50 patients with varying liver disease pathologies were prospectively recruited from the St. Mary’s Hospital Liver Unit in London; 25 with evidence of portal hypertension and 25 with no evidence of portal hypertension. Liver stiffness, spleen stiffness, spleen diameter and spleen area were measured using the Philips Affiniti 70 elastography point quantification point shear wave elastography system. The aspartate aminotransferase-to-platelet-ratio-index (APRI) score was also calculated. Performance measures, univariate and multivariate logistic regression were used to evaluate demographic, clinical and elastography variables. Interclass correlation coefficient was used to determine the reproducibility of splenic area and diameter.RESULTSOn univariate and individual performance, platelet count [area under the receiver operating characteristic (AUROC) 0.846, P value < 0.001], spleen area (AUROC 0.828, P value = 0.002) and APRI score (AUROC 0.827, P value < 0.001) were the most accurate variables in identifying the presence of portal hypertension. On multivariate logistic regression models constructed, the combination of spleen area greater than 57.90 cm2 and platelet count less than 126 × 109 had 63.2% sensitivity and 100% specificity, 100% positive predictive value and 100% negative predictive value. An alternative combination of spleen stiffness greater than 29.99 kPa and platelet count less than 126 × 109 had 88% sensitivity, 75% specificity, 78.6% positive predictive value and 85.7% negative predictive value. An interclass correlation coefficient value of 0.98 (95%CI: 0.94-0.99, P value < 0.001) and 0.96 (95%CI: 0.91-0.99, P value < 0.001) were determined for inter-operator variability for spleen area and diameter respectively.CONCLUSIONSpleen area, spleen stiffness and platelet count may be useful markers to assess the presence of portal hypertension in patients of various etiologies. 相似文献
95.
We undertook this study to assess the analgesic and anti-inflammatory properties of ibuprofen when administered through two drug delivery systems after mandibular third molar surgery. The study was conducted on 100 patients who required the surgical removal of impacted mandibular third molars under local anaesthesia. The study subjects were divided into two groups of 50 patients each. Patients in the study group were given ibuprofen-incorporated chitosan-based microspheres, which were packed into the third molar sockets after removal of impacted teeth. Patients in the control group were prescribed with ibuprofen 400mg tablets that were to be administered orally after the removal of impacted mandibular third molars. All patients were assessed for pain, swelling, and trismus on the second, fourth, and seventh postoperative days, and wound healing was assessed on the seventh postoperative day. Patients in the study group had significantly less pain and comparatively better mouth opening on the second, fourth, and seventh postoperative days, which showed clinically and statistically significant results of p<0.05, respectively, while the assessment of swelling for the study group did not show statistically significant results on any of the three postoperative days. Among 50 patients in the study group, two had wound gaping, and among 50 patients in the control group, four presented with wound gaping and three patients developed dry socket. Ibuprofen-incorporated chitosan-based microspheres (study group) had comparatively better analgesic and anti-inflammatory properties with drastic reduction of pain, swelling, trismus, and also had a reliable wound healing property when compared with the orally-administered ibuprofen (control group) after mandibular third molar surgery. 相似文献
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Breast cancer malpractice litigation in New York State 总被引:1,自引:0,他引:1