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1.
《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
2.
目的从三列凹顶藻Laurenciatristicha中寻找具有多样性结构的倍半萜化学成分,供药理活性筛选。方法采用凝胶柱色谱、硅胶柱色谱、重结晶和高效液相色谱等方法进行分离;借助包括一维和二维NMR等波谱方法和X-单晶衍射鉴定化合物的结构;用MTT法对得到的化合物进行细胞毒活性评价。结果分离得到5个倍半萜类化合物,分别鉴定为海兔阿普里素(aplysin,)、海兔阿普里醇(aplysinol,)、去溴海兔阿普里醇(debro-moaplysinol,)、凹顶藻联苯(laurebiphenyl,)、约翰斯顿醇(johnstonol,);在人肿瘤细胞株HCT-8、Bel-7402、BGc-823、A549和HeLa模型上,化合物对所有细胞株均显示毒性,化合物对HeLa细胞显示中等强度的细胞毒活性,其他化合物对所有细胞株均无明显毒性,IC50均大于10.0μg/mL。结论化合物~均为首次从三列凹顶藻中得到,化合物对HeLa细胞具有中等强度的选择性细胞毒活性,化合物对所有细胞株均显示毒性。 相似文献
3.
经穹隆结膜入路埋线法重睑成形术应用探讨 总被引:1,自引:0,他引:1
目的:通过分析重睑形成原理,综合比较多种重睑成形的方法,讨论埋线法重睑成形术的优点和可行性。方法:对387例患者行经穹隆结膜入路间断缝合埋线法重睑术。其中88例为其他方法埋线后重睑线消失的患者。结果:手术方法可靠,术后所形成的重睑外形良好,重睑维持时间长。最长随访时间38个月。结论:此方法因符合重睑形成原理,可以充分的将较多的上睑提肌腱膜与上睑皮肤结扎固定、故术后所形成的重睑牢固。且在直视下经穹隆结膜入路,降低了对眼球组织损伤的危险性。是埋线法重睑成形术一种可靠的手术方法。 相似文献
4.
We describe a simple direct extraction method for the gas-liquid chromatography determination of serum valproic acid. The working range for the assay is 2-180 mg/L and our within-run precision was 5.8 and 4.3% at the 40 and 90 mg/L concentrations respectively. Hemolyzed and lipemic sera as well as samples from patients with hyperbilirubinemia and from patients with decreased renal function were put through the assay and no interfering peaks were noted. Interference occurred when teflon-lined screw caps were used during the extraction step. The method was proven to be accurate by linear regression analysis of samples containing weighed-in amounts of valproic acid. The above assay was compared to an enzyme immunoassay technique (EMIT). The working range for the latter is 10-150 mg/L and the with-run precision was 10.8 and 5.9% and 90 mg/L concentration respectively. Samples were run by both the gas-liquid chromatograph and enzyme immunoassay methods and gave very similar results over the range 16-139 mg/L. 相似文献
5.
目的 探讨中央楔形切除及非对称性Z形切口小阴唇缩小术的临床应用效果.方法 在借鉴Giraldo术式基础上,提出了数值化的切口设计和组织切除;改变Z形切口为不对称的矩形瓣加斜行切口;小阴唇内外侧面反向设计.整形后的小阴唇近游离缘为两个矩形瓣相嵌合,其再与近小阴唇基底部的一斜行切口线相接.小阴唇内外两侧面的切口分别为反向设计.使之两侧面的切口相互错开,没有明显重叠.结果 应用治疗11例小阴唇肥大患者,小阴唇游离缘弧度自然、切口两侧无明显色差.结论 本术式定点准确,设计规则,掌握容易,适应证广,对不同程度的小阴唇肥大均适用. 相似文献
6.
Stenosis of the tracheostome is an occasional complication following laryngectomy. Having tried a number of procedures recommended for correction of such stenoses with limited results, we developed a new technique. This technique which is based on multiple Y-V plasties has been applied to 20 patients. Measurements of the stomal area following surgery in 18 patients showed an average increase in stomal size by a factor of 3.8. One patient apparently had no increase of the stoma. In 2, no post-operative measurements were available. Post-operative infection resulted in recurrence of the stenosis in one patient. He was successfully reoperated using the same technique. Follow-up revealed that none of the patients had complaints related to their stoma. 相似文献
7.
改进的内眦赘皮矫治术联合重睑成形术Ⅰ期成形 总被引:7,自引:2,他引:5
目的 探讨改进的内眦赘皮矫治术联合切开法重睑成形术的方法及临床效果。方法 根据内眦赘皮的轻重程度及方向,采用改良的“Z”成形术,切除或切断内眦部形成赘皮的异位眼轮匝肌及皮下筋膜组织,联合切开法重睑成形术行Ⅰ期成形。结果 本组68例患者,术后赘皮消失,泪阜显露适中,内眦间距缩短,重睑外形美观自然。其中,36例随访3个月至3年,术后皮肤切口无可见瘢痕,形态稳定,内眦赘皮无复发,效果满意。结论 该手术方法能够充分矫正内眦赘皮的异常结构,而与重睑成形术同期施术效果稳定,具有一定的临床应用价值。 相似文献
8.
A useful function of any complementary medicine is to supplement some of the benefits from other treatment modalities. In rats, extracts from Indian celery seed and the NZ green-lipped mussel are powerful nutraceuticals that (i) amplify the potency of salicylates and prednisone for treating pre-established chronic inflammation (arthritis, fibrosis) and (ii) reduce the steroid's gastrotoxic and lymphopenic side effects. Such combinations might also be useful for treating inflammatory components of (a) osteoarthritis caused by microcrystalline hydroxyapatite (BCP) and (b) pseudo-gout, associated with calcium pyrophosphate crystals; that are usually refractory to monotherapy. 相似文献
9.
A hybrid procedure combining the inverted scarf and crescentic osteotomies is presented. This procedure may serve as a viable modification of the inverted scarf bunionectomy for those surgeons desiring true rotational correction of high intermetatarsal angles. 相似文献
10.
Y. Misawa T. Saito H. Konishi S. Oki Y. Kaminishi K. Aizawa H. Takahashi O. Kamisawa M. Kato K. Fuse 《Journal of artificial organs》2002,5(3):0184-0187
We discuss the usefulness of the Cosgrove-Edwards ring from our early clinical results from 25 rings in 24 patients who underwent
mitral annuloplasty (MAP) or tricuspid annuloplasty (TAP) between June 1999 and December 2000. In the MAP group, the posterior
mitral annulus between the anterior and posterior fibrous trigones was reinforced with the prosthetic ring. In the TAP group,
the annuli of the anterior and posterior leaflets were splinted with the ring. The prosthetic ring was attached by pledgeted
U-sutures. Cardiologists performed echocardiography pre- and postoperatively. Thirteen of the 14 in the MAP group showed mitral
valve regurgitation of grade 0 or I. Six of the 11 in the TAP group showed tricuspid regurgitation of grade 0 or I, and 5
patients with regurgitation equal to or greater than grade II who remained in atrial fibrillation postoperatively recovered
without further clinical symptoms. No patient has required reoperation during a follow-up period of up to 2 years. Cosgrove-Edwards
ring-related complications, such as valve stenosis, ring detachment, and arrhythmia, have been not recognized in these patients.
In conclusion, for mitral and tricuspid annuloplasty, the Cosgrove-Edwards prosthetic ring showed excellent early clinical
results, particularly in patients maintained in sinus rhythm.
Received: November 5, 2001 / Accepted: May 30, 2002
Correspondence to:Y. Misawa 相似文献