A potential ethnic difference in the association between 5-HTTLPR polymorphisms and the brain default mode network

The serotonin-transporter-linked polymorphic region （5-HTTLPR） is associated with mood disorders. This association is thought to be due to amygdala hyper- responsiveness to negative emotional stimuli as a result of reduced frontal cortical control. In Caucasians, the short form is associated with this effect, but in Han Chinese we recently found that the long form is involved. Serotonin receptors have rich expression in default mode network （DMN） regions and the recent studies have found an association between the short form of the 5-HTTLPR and DMN functional connectivity （FC） in Caucasians. The present study has investigated whether there may also be an ethnic difference in this influence of 5-HTTLPR on the DMN. We recruited 233 young Han Chinese subjects and calculated the resting-state default-network FC. Our study found that the L carriers had decreased FC in the bilateral medial prefrontal cortex, right parahippocampal gyrus, left middle temporal gyrus, and increased FC in left precuneus （Pcu） compared to SS. The PCC-Pcu FC in L carriers was significantly negatively correlated with the depression scores. Our findings, therefore, suggest that there is also a difference between Caucasian and Han Chinese subjects in the association between the different forms of the 5-HTTLPR and DMN functional connectivity.     

Control dynamics of severe acute respiratory syndrome transmission

Severe acute respiratory syndrome (SARS) is a serious disease with many puzzling features. We present a simple, dynamic model to assess the epidemic potential of SARS and the effectiveness of control measures. With this model, we analysed the SARS epidemic data in Beijing.The data fitting gives the basic case reproduction number of 2.16 leading to the outbreak, and the variation of the effective reproduction number reflecting the control effect. Noticeably, our study shows that the response time and the strength of control measures have significant effects on the scale of the outbreak and the lasting time of the epidemic.     

Universal thermodynamic model of calculating the mass action concentrations of omponents in a ternary strong electrolyte aqueous solution and its application in the NaCl-KCl-H2O system

A universal thermodynamic model of calculating the mass action concentrations of components in a ternary strong electrolyte aqueous solution has been developed based on the ion and molecule coexistence theory,and verified in the NaCl-KCl-H₂O ternary system at 298.15 K. To compare the difference of the thermodynamic model in binary and ternary strong electrolyte aqueous solutions,the mass action concentrations of components in the NaCl-H₂O binary strong electrolyte aqueous solution were also computed at 298.15K. A transformation coefficient was required to compare the calculated mass action concentration and reported activity because they were obtained at different standard states and concentration units. The results show that the transformation coefficients between calculated mass action concentrations and reported activities of the same components change in a very narrow range. The calculated mass action concentrations of components in the NaCl-H₂O and NaCl-KCl-H₂O systems are in good agreement with the reported activities. This indicates that the developed thermodynamic model can reflect the structural characteristics of solutions,and the mass action concentration also strictly follows the mass action law.     

A mass transfer model for predicting emission of the volatile organic compounds in wet building materials

A new mass transfer model is developped to predict the volatile organic compounds （VOCs） from fresh wet building materials. The dry section of wet materials during the process of VOC emission from wet building materials is considered in this new model, differing from the mass transfer-based models in other literatures. The mechanism of effect of saturated vapor pressure on the surface of wet building materials in the process of VOC emission is discussed. The concentration of total volatile organic compounds （TVOC） in the building materials gradually decreases as the emission of VOCs begins, and the vapor pressure of VOCs on the surface of wet building materials decreases in the case of newly wet building materials. To ensure the partial pressure of VOCs on the surface of wet building materials to be saturated vapor pressure, the interface of gas-wet layer is lowered, and a dry layer of no-volatile gases in the material is formed. Compared with the results obtained by VB model, CFD model and the experiment data, the results obtained by the present model agree well with the results obtained by CFD model and the experiment data. The present model is more accurate in predicting emission of VOC from wet building materials than VB model.     

A thermodynamic model of calculating mass action concentrations for structural units or ion couples in NaClO4-H2O and NaF-H2O binary solutions and NaClO4-NaF-H2O ternary solution

A thermodynamic model of calculating mass action concentrations for structural units or ion couples in NaClO₄-H₂O and NaF-H₂O binary solutions and NaClO₄-NaF-H₂O ternary strong electrolyte aqueous solutions was developed based on the ion and molecule coexistence theory (IMCT). A transformation coefficient was needed to compare the calculated mass action concentration and the reported activity, because they were usually obtained at different standard states and concentration units. The results show that transformation coefficients between the calculated mass action concentrations and the reported activities of the same components change in a very narrow range. The transformed mass action concentrations of structural units or ion couples in NaClO₄-H₂O and NaF-H₂O binary solutions agree well with the reported activities. The transformed mass action concentrations of structural units or ion couples in NaClO₄-NaF-H₂O ternary solution are also in good agreement with the reported activities in a total ionic strength range from 0.1 to 0.9 mol/kg H₂O by the 0.1 mol/kg step with different ionic strength fractions of 0, 0.2, 0.4, 0.5, 0.6, 0.8, and 1, respectively. The results indicate that the developed thermodynamic model can reveal the structural characteristics of binary and ternary strong electrolyte aqueous solutions, and the calculated mass action concentrations of structural units or ion couples also strictly follow the mass action law.     

Ultra-Cut biopsy guided by ultrasonography for liver lesions：experience of 392 clinical cases

We conducted a retrospective study of the accuracy of liver biopsies in 392 patients with liver lesions. Postbiopsy diagnosis was 297 cases of primary liver cancers, 79 cases of secondary malignant tumors, 2 cases of non-Hodgkin‘s lymphorna, 10 cases of focal nodular hyperplasia, 2 cases of chronic inflammation, 1 tuberculosis case and 1 schistosomiasis case. Biopsy provided histological diagnosis in 100% of cases, sensibility and specificity of Ultra-Cut biopsy was 98.95% and 100% for the diagnosis of malignancy respectively; positive predictive value, 100% ; negative predictive value, 71.43% ; and accuracy, 98.98 %. We identified no major procedure related complications despite the presence of thrombocytopenia in 37. 5% of cases. Pain was the only reported adverse effect of liver biopsy (10.97%), and 11 patients required analgesics. We concluded that Ukra-Cut liver biopsy was a safe and effective technique, and was invaluable in the investigation and management of patients with liver lesions.     

Dust-cloud structures behind a shock wave moving over a deposited layer of fine particles

The present paper investigates dispersed-phase flow structures of a dust cloud induced by a normal shock wave moving at a constant speed over a flat surface deposited with fine particles. In the shock-fitted coordinates, the general equations of dusty-gas boundary layer flows are formulated within the framework of a multi-fluid model and parametric numerical studies of the carrier- and dispersed-phase flow fields are performed. The problem associated with crossing particle trajectories and the formation of local particle accumulation regions are solved by using the full Lagrangian method for the dispersed phase. The basic features of the near-wall two-phase flow under consideration including the role of Saffman force in the particle entrainment and the development of discontinuities or singularities in the particle density profiles are discussed. The effects associated with account of the non-uniformity of particle size and the finiteness of the particle Knudsen numbers are studied in detail.     

Neural suppression of distractors surrounding the spotlight: Evidence from steady-state visual evoked potentials

The present study investigated the allocation of spatial attention using steady-state visual evoked potentials(SSVEPs).The SSVEP is elicited in visual cortical areas by a repetitive flicker having the same fundamental frequency as the driving stimulus.Two flickers were applied with the letter stream presented in the center of the monitor and the distractor presented on either the left or right side of the target.Participants were instructed to detect the target letter in the letter stream.The distance of the two flickers was manipulated.The results show that the amplitudes of the SSVEPs elicited by the distractor were enhanced when it was in the closest position and suppressed when it was at a farther distance.But the amplitudes rebounded at the farthest distance.Meanwhile,the SSVEP elicited by the target flicker remained stable independent of the distance of the distractor.Thus,the present study indicates that focused attention involves neural suppression surrounding the classic "spotlight",and the SSVEP paradigms open new avenues for studying the attentional suppression mechanism.     

FINITE ELEMENT SIMULATION OF FABRIC CANTILEVER TEST

The present paper describes the application of the finite element technique to simulate large fabric deformations in the case of a rectangular cantilever. The fabric is simulated using a degenerated isoparametric curved shell element with 8 nodes. The cantilever is considered as a special case of a three dimensional shell structure. The finite element formulation takes into account nonlinear material properties of fabrics. Simulation of woven fabric cantilevers is made and the results are compared with the test results to examine the effectiveness of the finite element approach.     

A Back Look on the Binary Phase Diagrams of Metals from the Mass Action Law and the Coexistence Theory of Metallic Melts

According to the mass action law and the coexistence theory of metallic melts, the mass action concentrations of Cu-Mg, Bi-Tl and Ni-Al melts involving compound formation have been calculated. The calculated results show that, except the ultimate case of pure element, when two elements are present in the melts, all structural units (atoms and molecules) without exception will be present in the melts, i.e., their concentrations may change from great to small, but they will not vanish into nothing, and only under such conditions, the calculated results both agree with practice and obey the law of mass action. In view of that over considerable wide composition range, the activities of both elements of the three solid binary alloys mentioned above have been measured, this seems in contradiction with the present relevant phase diagrams, in which the structural units are determined by composition range, so the latter needs further investigation and consideration.     

CT靶扫描在肾上腺疾病诊断中的价值

目的：评价CT薄层靶扫描在肾上腺疾病定位与定性诊断中的作用。方法：回顾性分析了55例病人56处经手术病理证实的肾上腺病变的CT影像资料,重点分析其形态、大小、密度及边缘情况。CT检查均为平扫与增强及薄层靶扫描。结果：肾上腺增生22例,CT表现主要为体积增大,其中髓质增生14例,肾上腺皮质增生8例,两者在形态及大小的CT表现无差别;肾上腺皮质增生中结节性增生4例,增强扫描后均为轻度强化;肾上腺皮质腺瘤14例,增强扫描后,轻度强化5例,中等强化7例,明显强化2例。34例肾上腺肿瘤性疾病的CT影像诊断符合率为77．14％。在定性诊断中,CT诊断与病理结果相一致有39例,误诊17例。结论：CT靶扫描在肾上腺疾病的定位及定性诊断中具有很高的价值。CT对大多数的肾上腺肿瘤性疾病诊断较为敏感;对于肾上腺髓质增生与皮质增生的鉴别,则没有明显的特异性;肾上腺皮质腺瘤可与皮质结节性增生鉴别。     

Granulomatous hypophysitis: two case reports and literature review

Granulomatous hypophysitis (GRH) is extremely rare and commonly presents with chronic inflammatory of the enlarged pituitary gland. In our study, 66-year-old and 57-year-old women, both Chinese, were diagnosed with GRH presenting preoperatively definite imageology characters as pituitary adenoma. The 66-year-old woman presented with a year of headache, half a year of gradual decrease of visual acuity, and one month of right ptosis. Serum prolactin level was slightly elevated. Screening computed tomography (CT) scanning revealed typical low density mass found on the enlarged sella, which demonstrated invasive extension from the sella to the right cavernous sinus by contrast enhanced magnetic resonance imaging (MRI). Consequently, the patient was diagnosed with probable invasive pituitary adenoma. The other 57-year-old woman complained a light headache and had been previously treated as nonfunctional pituitary adenoma in other hospital. Finally these two patients underwent transsphenoidal microsurgery and were diagnosed with GRH according to postoperative histopathology. They then were treated with steroid. During the follow-up, the clinical symptoms such as headache, visual damage, and ptosis vanished, and the mass of the sellae dramatically shrank on repeated MR images. Clinically and radiologically, GRH is a rare sellar entity easily to be misdiagnosed as a pituitary adenoma. Trans-sphenoidal surgery can decompress the optical nerve or oculomotornerve as a therapeutic strategy, and support biopsy or further pathological diagnosis. However, the hormonal therapy should be emphasized both as diagnostic and therapeutic strategies. Conservative and tentative steroid treatment should be performed in preoperative period without acute nerve damage.     

7例左心发育不全综合征的姑息手术治疗

通过美国俄亥俄州医学院所见7例左心发育不全综合征的手术治疗,体会左心发育不全综合征畸型较为复杂和严重,所有本病患儿都应列为手术对象。近年来国外学者报道对本病采取各种姑息手术作为第一期(初期)手术。常用的有 Norwood 术式或其他改良术式比较接近生理和血流动力学的要求。     

On indexing in the Web of Science and predicting journal impact factor

We discuss what document types account for the calculation of the journal impact factor （JIF） as published in the Journal Citation Reports （JCR）. Based on a brief review of articles discussing how to predict JIFs and taking data differences between the Web of Science （WoS） and the JCR into account, we make our own predictions. Using data by cited-reference searching for Thomson Scientific＇s WoS, we predict 2007 impact factors （1Fs） for several journals, such as Nature, Science, Learned Publishing and some Library and Information Sciences journals. Based on our colleagues＇ experiences we expect our predictions to be lower bounds for the official journal impact factors. We explain why it is useful to derive one＇s own journal impact factor.     

原发性髂股静脉血栓形成诊断诊治探讨

三年来收治发病后三天内的急性原发性左髂股静脉血栓形成3例。第1例术后给肝素抗凝治疗,同时给低分子右旋醣酐、阿斯匹林、潘生丁等祛聚辅助治疗。出院后遗留下肢静脉功能不全。第2例术后除应用抗凝、祛聚等治疗外,还给尿激酶溶栓治疗,伤口两个多月才愈合,出院后下肢静脉功能良好。第3例单纯应用尿激酶溶栓,辅以祛聚药物,出院后下肢静脉功能良好。     

Aortoduodenal fistula following aortic reconstruction of a pseudoaneurysm caused by stab wound 12 years ago

Gastrointestinal bleeding due to aortoenteric fistula is extremely rare. Aortoenteric fistula is difficult to be diagnosed timely and entails a significant morbidity and mortality. Herein, we present an uncommon case of gastrointestinal bleeding caused by aortoduodenal fistula, which was a complication of a successful aortic reconstruction 4 months ago for an aortic pseudoaneurysm resulted from a stab wound 12 years ago. An urgent laparotomy confirmed an aortoduodenal fistula and repaired the defects in aorta and duodenum, but a prolonged shock led to the patient’s death. In summary, early diagnosis and surgical intervention for aortoenteric fistula are vital for survival.     

中场强MR化学位移技术在肾上腺腺瘤诊断中的应用

目的在于探讨中场强MR化学位移技术对肾上腺腺瘤的诊断价值。在材料和方法上回顾性收集肾上腺各类肿瘤13例，均使用化学位移及其它MR序列成像，并比较其成像效果，所有病例均经手术证实。其结果除直径超过5CM的较大病灶由于出血坏死等因素影响外，多数肾上腺腺瘤均表现为去相位信号均匀性减低，而其它病变无类似表现。可见中场强MR化学位移技术对于肾上腺腺瘤的诊断与鉴别诊断具有重要价值。     

中华分支睾吸虫病与原发性肝（胆管）癌关系的研究（附病例报告）

本文报道一较典型华支睾吸虫痛所致原发性肝胆管癌病例。患者经B超、肝扫描、CT均显示“肝内占位性病变”,行选择性肝动脉造影证实“肝右叶肿瘤”。外科作肝肿瘤切除并送病理检查,确诊肝华支睾吸虫感染伴发肝胆管上皮腺瘤样增生,肝胆管上皮癌变及胆管腺癌。对华支睾吸虫病所致原发性肝胆管癌的病理变化过程,作了较详细的描述,同时对其发病机理进行了讨论。鉴于原发性肝胆管癌目前治疗尚有一定困难,病死率极高,作者认为积极防治华支睾吸虫病,将对流行区内原发性肝胆管癌发病率的下降及对原发性肝胆管癌的防治会具有极为重要的意义。     

胃部肿物25例诊断与治疗探讨

我院外科三年来收治胃部肿物病人25例,其中经多间医院各项检查,术前误诊者6例,误诊率高达24％。胃癌、胃平滑肌瘤各1例误诊为胰腺肿瘤,胃平滑肌母细胞瘤误诊为肝癌1例,以上三例均因胃肿物呈腔外性,致胃钡餐检查呈外压性改变。胃恶性淋巴瘤及假性淋巴瘤各1例,则因纤维光束胃镜检查,疑为胃癌而病理活检阴性所致。1例胃内异位胰腺,亦因胃镜检查及病理活检误诊为胃息肉所致。胃部肿物治疗问题,如无手术禁忌,应尽量争取剖腹探查手术。对有一定活动性的巨大胃肿物,有可能是良性而可以切除治愈的,不应轻易放弃手术治疗。对晚期胃癌病人,如身体条件许可,应进行姑息性切除,以改善全身中毒情况,有可能延长病人生命。本组有三例外院放弃手术治疗病例,均经手术治愈出院,其中有两例属于良性肿瘤。     

纤毛虫阔口游仆虫皮层微管胞器的形态及形态发生

采用荧光紫杉醇直接荧光标记,研究了腹毛类纤毛虫阔口游仆虫(Euplotes eurystomus)中由纤毛器、纤毛器附属微管和非纤毛器微管组成的皮层微管胞器.其中纤毛器、纤毛器附属微管包括口围带及小膜托架微管,波动膜及基部微管骨架网,额腹横棘毛、左缘棘毛及基部的前纵维管束、后纵微管束和横微管束,背触毛及基部的玫瑰花环附属微管等;非纤毛器皮层微管包括背腹面的细小网格状微管,背面的斜向微管层及贯穿于细胞纵长的纵微管层等.形态发生中,老口围带被前仔虫继承,前、后仔虫的额腹横棘毛发生及分化过程中老纤毛器基部微管退化,并且老棘毛及其附属微管可能具有定位和定向作用,但未见直接的物质联系.所得结果为揭示腹毛目纤毛虫皮层微管胞器建构的多样性、细胞皮层微管的分化及其细胞调控提供了基础资料.