Bile duct obstruction: radiologic evaluation of level, cause, and tumor resectability

In a prospective study of 65 patients with bile duct obstruction, various radiologic modalities were compared for their capability to demonstrate the level and cause of obstruction and to indicate accurately tumor resectability. Ultrasound (US) was performed in 65 patients, computed tomography (CT) in 51, direct cholangiography (DC) in 57, and angiography in 35. The level of obstruction was correctly indicated by US in 95% of patients and by CT in 90%, and the cause was correctly indicated by US in 88%, by CT in 63%, and by DC in 89%. In predicting tumor resectability, US was correct in 71% of patients, compared with 42% for CT, 58% for DC, and 25% for angiography. US therefore appears to be the single most useful modality in the evaluation bile duct obstruction.     

肝细胞生长因子基因转染骨髓间充质干细胞对脂肪颗粒移植存活率的影响

目的研究携带人肝细胞生长因子基因的重组腺病毒（Ad—HGF）修饰骨髓间充质干细胞（MSCs）对大鼠脂肪颗粒移植存活率的影响。方法用携带绿色荧光蛋白的重组腺病毒（Ad-GFP）、Ad—HGF转染雄性Wistar大鼠MSCs,测定转染效率与感染上清中肝细胞生长因子（HGF）的表达。用雌性Wistar大鼠150只,随机分为5组：空白对照组（A组）、Ad—HGF组（B组）、MSCs组（C组）、Ad—GFP感染MSCs组（D组）和Ad—HGF感染MSCs组（E组）,每组30只。各组均匀振动5分钟,将颗粒脂肪移植于自体背部皮下;移植后3、5、7、14、28、60d,每组各取5只大鼠脱颈处死,取出移植物;测体积、HE、Masson染色观察病理改变,免疫组织化学法测定组织中HGF表达和血管生成。结果积分吸光度＝100时,Ad—GFP转染MSCs效率可达89．6％;移植后3、5、7、14d,E组移植物中HGF的表达高于其他各组（P〈0．05）;移植后5、7、14、28、60d,E组血管数量也多于其他各组（P〈0．05）;28d和60d时,E组脂肪颗粒体积保持率明显好于其他4组（P〈0．05）。结论携带HGF基因的MSCs在移植物中能够持续表达HGF,有效地减少脂肪颗粒移植后的吸收,从而提高移植颗粒脂肪的存活率。     

RNase H confers specificity in the dnaA-dependent initiation of replication at the unique origin of the Escherichia coli chromosome in vivo and in vitro.

Escherichia coli rnh mutants defective in RNase H activity display the features of previously described sdrA (stable DNA replication) and dasF (dnaA suppressor) mutants: (i) sustained DNA replication in the absence of protein synthesis, (ii) lack of requirement for dnaA protein and the origin of replication (oriC), and (iii) sensitivity of growth to a rich medium. Both the sdrA mutants (selected for continued DNA replication in the absence of protein synthesis) and the dasF mutants (selected as dnaA suppressors) are defective in RNase H activity, measured in vitro. Furthermore, a 760-base-pair fragment containing the rnh+ structural gene complements the phenotype of each of the rnh, sdrA, and dasF mutants, indicative of a single gene. One function of RNase H in vivo is in the initiation of a cycle of DNA replication at oriC dependent on dnaA+. In keeping with these results, RNase H contributes to the specificity of dnaA protein-dependent replication initiated at oriC in a partially purified enzyme system.     

The effect of the radial function on I-125 seeds used for permanent prostate implantation.

The purpose of this study was to evaluate the integrity of eight commercially-available low-activity Iodine-125 (125I) seeds for their radial function g(r) and its effect on the dose delivered to the adjacent critical structures when used in permanent prostate implants (PPI). Ten previously treated patients were retrospectively used in this comparison. The Amersham Health Oncura seed was used to peripherally design an isodose distribution with urethral and anterior rectal wall sparing. Plan criteria included minimum coverage of 144 Gy to the planning target volume (PTV), < or = 70% dose to 150% of the PTV volume (V150-PTV), and the quantity of needles < or = 70% of the size of the PTV, in cc. Upon completion of the Oncura plan, the seed type was changed and the activity was adjusted until the V100-PTV for each of the other 7 seed types matched the V100-PTV defined by the Oncura seed. Computed tomography (CT)-based postimplant dosimetry was used to determine the dose to 40% (D40) of the bulb of the penis (in Gy). Dose-volume histograms (DVH) were used to evaluate the differences to V100 (in %) and D40 (in Gy) of the anterior rectal wall and bulb of the penis, and V100 (in %) of the urethra. The data was tabulated. Radioactive 125I sources included in this study were 125I Source 2301 (Best); I-Plant (MedTech), IoGold (Mentor), Oncura (Amersham Health), ProstaSeed (UroCor), SelectSeed (Nucletron), SourceTech (Bard), and Symmetra (UroMed). The sizes of the PTV for the 10 patients ranged from 18.82 cc to 48.99 cc. The Oncura seed was used as the reference seed and all other seed types were normalized to it for data comparison. It was determined that the dose rate constant (Delta) and anisotropy factor (phi) contribute to the activity needed to achieve comparable V100-PTV doses, but a strong dependence on the radial function g(r) was found to effect the doses to the critical structures studied. Values of g(r) at 4 cm were calculated and the IoGold and SourceTech seeds were determined to have the highest g(r) values, with ProstaSeed and SelectSeed having the lowest values. 125I Source 2301 and IoGold required less activity per seed to achieve the same dose to the V100-PTV due to the higher dose rate and anisotrophy constants (Delta.phi). The seed types with silver were less penetrating and resulted in the production of characteristic x-rays that modified the energy spectrum and influenced the radial function. The seeds requiring the lowest activity showed the highest dose to the anterior rectal wall, a posterior adjacent structure; the urethra, an interior structure; and the bulb, an inferior structure. This study was designed to investigate the integrity of eight different commercially-available seed types, and their dependence on the g(r) in seed choice. It was determined that the dose rate constant and anisotropy factor determine the activity needed for implantation but a strong dependence on the radial function was found to effect the doses to the adjacent structures.     

Production of type II heat-labile enterotoxin by Escherichia coli isolated from food and human feces.

Escherichia coli strains isolated in Sao Paulo, Brazil, from feces of patients with diarrhea and from food samples produced toxin(s) that was shown to be related both immunologically and genetically to the recently characterized type II heat-labile enterotoxin of E. coli. The new isolates of type II heat-labile enterotoxin-producing E. coli belonged to five different serotypes and did not represent a single clone.     

MR运动成像对CSM诊断的临床研究

目的探讨MR运动成像对脊髓型颈椎病（cervical spordylogic myelopathy,CSM）的诊断价值。方法比较52例患者常规（静态）MR成像和MR运动成像检查结果,观察分析CSM患者脊髓受压的因素和特征,并与正常组MR表现进行对照分析。常规MR成像采用SE、FSE矢状位及横断位T1WI、T2WI或STIR等序列。MR运动成像采用FSE矢状位T2WI序列观察分析颈椎过屈、自然和过伸位MR征象特点。结果52例患者中,常规MR成像发现脊髓压迫46例,其中1级9例,2级26例,3级11例。MR运动成像全组病例均见脊髓压迫,其中1级10例,2级29例,3级13例。结论MR运动成像可动态观察CSM患者脊髓受压的因素及特征,并且能早期发现椎体不稳,为临床制定合适治疗方案及早期干预提供较可靠依据。     

中药强骨丹对去卵巢骨质疏松大鼠骨密度和骨生物力学的影响

[目的]观察中药强骨丹对去卵巢骨质疏松大鼠骨密度和骨生物力学的影响,探讨其治疗绝经后骨质疏松症的作用。[方法]运用切除大鼠卵巢方法建立去卵巢骨质疏松症模型,随机分为假手术组、模型组、强骨丹高、低剂量组和西药组5组,每组10只。摘除卵巢后第4天分别给予生理盐水、强骨丹高、低剂量和二膦酸盐,各组均在服药14周后处死动物,进行血清雌二醇、骨密度、骨矿含量和骨生物力学测定。[结果]强骨丹能够明显升高去卵巢骨质疏松大鼠血清雌二醇水平,使骨密度和骨矿含量增加,胫骨最大载荷显著提高。[结论]强骨丹可通过提高机体雌激素水平,降低骨的转换率,增加骨密度,有效维持骨生物力学性能,对绝经后骨质疏松症有防治作用。     

改良无抽搐电休克合并氟西汀与单用氟西汀治疗抑郁症的对照研究

目的观察改良无抽搐电休克(MECT)合并氟西汀治疗抑郁症的疗效及副反应。方法将60例符合CCMD-3抑郁发作诊断标准的抑郁症患者随机分为MECT合并氟西汀治疗组和单用氟西汀治疗组,共观察6周。采用汉密顿抑郁量表、汉密顿焦虑量表、临床总体评定量表评定临床疗效,采用副反应量表评定副反应。结果根据HAMD评分,两组2周末显效率分别为80%、40%,两组间差异具有显著性(P<0.05);6周末显效率分别为93.3%、76.7%,差异无显著性(P>0.05)。MECT并氟西汀治疗组HAMA评分在1、2、4周末明显少于单用氟西汀组,且有显著性差异(P<0.05或P<0.01)。MECT并氟西汀治疗并未增加副反应,且失眠少于氟西汀组(P<0.05)。结论MECT并氟西汀治疗抑郁症起效快、疗效确切、安全。     

Association between palmoplantar pustulosis and cigarette smoking in Brazil: a case–control study

Background  Palmoplantar pustulosis (PPP) discloses some differences compared to vulgar psoriasis (PV) in terms of age of onset, female predominance and low occurrence of psoriasis lesions elsewhere. Cigarette smoking has been associated to PPP in international studies; nevertheless, these studies were never performed among Brazilian.
Objectives  To compare prevalence of smoking among PPP, PV and other dermatologic patients (NPD).
Methods  Case–control study involving 25 PPP patients from a reference psoriasis centre. Two control groups were matched according to gender and age: 50 patients with PV and 50 NPD. Confounders were adjusted by conditional multiple logistic regression.
Results  Among cases, 84.0% were female and PPP age of disease onset (41.4 years) was greater than PV (34.5 years). Prevalence of ever smoking was higher among cases (92.0%) than PV (52.0%) and NPD (30.0%). Adjusted odds ratio of PPP ever smoking compared to PV and NPD was 9.5 and 36.2, respectively. All smokers reported the onset of their habit before the development of PPP.
Conclusions  There was significant association between PPP and smoking. However, the impact of giving it up in the clinical course of the disease remains to be established.