经口咽入路行枕骨大孔扩大术的解剖学基础研究

目的：对枕骨斜坡骨性结构及周围毗邻关系的解剖学测量,为经口咽入路行枕骨大孔扩大术提供详尽的解剖学数据及理论依据。方法：①选取成人干燥颅骨标本40例,分别测量斜坡颅底内面、颅底外面的长度;斜坡咽结节处宽度、斜坡最小厚度、中部厚度和最大厚度;斜坡与水平面的夹角;颈动脉管外口内缘、颈静脉孔内外口内缘、破裂孔内外口内缘、舌下神经内外口内缘、寰枕关节内缘与斜坡中线的距离。②选取完整头颈部标本20例,观察斜坡与周围血管神经的毗邻关系。结果：①斜坡颅底内面长（40.1±2.5）mm,外面长（28.2±3.1）mm;斜坡中部宽度（18.8±2.5）mm,;最小厚度（6.8±2.3）mm,;中部厚度（9.8±2.2）mm,最大厚度（11.5±1.7）mm;咽结节至枕骨大孔前缘距离（12.8±1.5）mm。②斜坡与水平面的夹角（46.8±4.5）°。③颈动脉管外口内缘距离斜坡中线（26.1±3.1）mm,颈静脉孔内口内缘距离斜坡中线（21.8±2.5）mm,颈静脉孔外口内缘距离斜坡中线（25.1±2.7）mm,破裂孔内口内缘距离斜坡中线（10.5±2.9）mm,破裂孔外口内缘距离斜坡中线（11.8±2.5）mm,舌下神经管内口内缘距离斜坡中线（13.8±2.3）mm,舌下神经管外口内缘距离斜坡中线（21.1±2.3）mm,寰枕关节内缘距离斜坡中线（10.5±2.3）mm。④斜坡上部距离后方基底动脉（7.6±1.0）mm,距离后方脑桥（8.3±1.2）mm,斜坡中部距离后方延髓脑桥沟（13.5±1.7）mm,斜坡下部距离后方延髓（6.5±0.8）mm。⑤斜坡上部与后方硬脑膜之间间隙为（1.8±0.2）mm,斜坡中部与后方硬脑膜之间间隙为（1.3±0.1）mm,斜坡下部与后方硬脑、脊膜之间间隙为（1.3±0.1）mm。⑥在斜坡开骨窗的宽度为20mm,高度为15mm,深度为6mm,可以满足经口咽入路枕骨大孔扩大术的要求,并有可靠的安全性。结论：本研究通过对斜坡骨性结构及周围毗邻关系的测量与观察,为临床斜坡区手术提供解剖学数据。     

颧根与侧颅底重要结构的解剖学测量

目的:通过测量颧根与侧颅底各重要结构间的距离关系,为临床侧颅底外科手术治疗提供定位参考。方法:取成人颅骨标本50例(去颅盖标本8例,整颅42例)100侧,用游标卡尺、圆规和直尺测量颧根与侧颅底重要结构的距离。结果:实验测得左右侧颧根与外耳门前缘中点、乳突尖、茎突、翼突外侧板根部、舌下神经管外口、茎乳孔、颈静脉孔外缘、颈动脉管外口后缘、棘孔、卵圆孔、破裂孔的距离分别为22.30±2.84mm和22.02±3.27mm、40.37±3.21mm和40.56±3.54mm、32.53±2.78mm和32.92±2.68mm、35.13±3.14mm和35.19±2.74mm、49.29±2.88mm和48.98±2.87mm、32.92±2.44mm和33.05±2.61mm、35.15±2.86mm和34.68±3.13mm、33.17±2.78mm和33.17±2.72mm、28.83±2.62mm和28.68±2.63mm、31.15±2.76mm和31.49±2.73mm、43.67±3.32mm和44.15±3.02mm,左右侧数据无差异(P>0.05)。结论:颧根可以作为侧颅底外科手术的定位标志,为直视条件下经颞下等入路的侧颅底外科手术提供解剖学依据。     

颧根与侧颅底重要结构的解剖学测量

目的：通过测量颧根与侧颅底各重要结构间的距离关系,为临床侧颅底外科手术治疗提供定位参考。方法：取成人颅骨标本50例（去颅盖标本8例,整颅42例）100侧,用游标卡尺、圆规和直尺测量颧根与侧颅底重要结构的距离。结果：实验测得左右侧颧根与外耳门前缘中点、乳突尖、茎突、翼突外侧板根部、舌下神经管外口、茎乳孔、颈静脉孔外缘、颈动脉管外口后缘、棘孔、卵圆孔、破裂孔的距离分别为22.30±2.84mm和22.02±3.27mm、40.37±3.21mm和40.56±3.54mm、32.53±2.78mm和32.92±2.68mm、35.13±3.14mm和35.19±2.74mm、49.29±2.88mm和48.98±2.87mm、32.92±2.44mm和33.05±2.61mm、35.15±2.86mm和34.68±3.13mm、33.17±2.78mm和33.17±2.72mm、28.83±2.62mm和28.68±2.63mm、31.15±2.76mm和31.49±2.73mm、43.67±3.32mm和44.15±3.02mm,左右侧数据无差异（P〉0.05）。结论：颧根可以作为侧颅底外科手术的定位标志,为直视条件下经颞下等入路的侧颅底外科手术提供解剖学依据。     

乳突切迹与侧颅底重要结构的解剖学观测及应用

目的:通过测量乳突切迹与侧颅底重要骨性结构的距离,为临床相关应用提供解剖学参考。方法:取成人颅骨标本50例(去颅盖标本8例,整颅42例)100侧,测量乳突切迹及其与侧颅底重要孔、裂和管的距离。结果:左右侧乳突切迹后缘距茎乳孔、颈静脉孔外侧缘、颈动脉管外口后缘、破裂孔、棘孔、卵圆孔距离分别为25.16±3.73cm和25.02±3.58cm、30.92±3.50cm和30.45±3.49cm、38.22±3.57cm和38.14±3.43cm、57.23±3.71cm和57.14±3.44cm、47.94±3.83cm和48.32±3.54cm、53.70±3.98cm和53.55±3.75cm。结论:以乳突切迹后缘做为侧颅底手术的定位标志能够为临床相关应用提供较方便、准确的定位参考。     

以乳突切迹和翼钩为基点的侧颅底分区方法

目的:探讨以乳突切迹和翼钩为基点的侧颅底分区新方法.方法:在乳突切迹后缘、翼钩、枕骨大孔前缘中点和颧根四个结构间相互连线,区分侧颅底并测量连线的长度.结果:乳突切迹与侧颅底重要结构的关系密切,切迹后缘与翼钩连线和正中线将侧颅底分成内、外侧两个大的三角区,每个区再分成前后两个三角区共四个三角区,即腭和颞下三角、咽三角、关节和听三角、血管神经三角,其中血管神经三角的三边长度左右侧分别为(74.52±5.47)mm和(74.66±5.41)mm、(59.77±3.84)mm和(59.67±3.56)mm、(42.23±3.11)mm和(42.48±2.60)mm.结论:本研究提供了新的侧颅底分区方法,且血管神经三角的区域划分更为科学,为临床侧颅底手术入路和定位提供了解剖学参考.     

乳突切迹与侧颅底重要结构的解剖学观测及应用

目的：通过测量乳突切迹与侧颅底重要骨性结构的距离,为临床相关应用提供解剖学参考。方法：取成人颅骨标本50例（去颅盖标本8例,整颅42例）100侧,测量乳突切迹及其与侧颅底重要孔、裂和管的距离。结果：左右侧乳突切迹后缘距茎乳孔、颈静脉孔外侧缘、颈动脉管外口后缘、破裂孔、棘孔、卵圆孔距离分别为25.16±3.73cm和25.02±3.58cm、30.92±3.50cm和30.45±3.49cm、38.22±3.57cm和38.14±3.43cm、57.23±3.71cm和57.14±3.44cm、47.94±3.83cm和48.32±3.54cm、53.70±3.98cm和53.55±3.75cm。结论：以乳突切迹后缘做为侧颅底手术的定位标志能够为临床相关应用提供较方便、准确的定位参考。     

以乳突切迹和翼钩为基点的侧颅底分区方法

目的：探讨以乳突切迹和翼钩为基点的侧颅底分区新方法。方法：在乳突切迹后缘、翼钩、枕骨大孔前缘中点和颧根四个结构间相互连线,区分侧颅底并测量连线的长度。结果：乳突切迹与侧颅底重要结构的关系密切,切迹后缘与翼钩连线和正中线将侧颅底分成内、外侧两个大的三角区,每个区再分成前后两个三角区共四个三角区,即腭和颞下三角、咽三角、关节和听三角、血管神经三角,其中血管神经三角的三边长度左右侧分别为（74.52±5.47）mm和（74.66±5.41）mm、（59.77±3.84）mm和（59.67±3.56）mm、（42.23±3.11）mm和（42.48±2.60）mm。结论：本研究提供了新的侧颅底分区方法,且血管神经三角的区域划分更为科学,为临床侧颅底手术入路和定位提供了解剖学参考。     

颅底孔在多层CT三维重建中的测量研究

探讨颅底MSCT三维重建图像效果及主要孔的正常值,采用多层螺旋CT(MSCT),对200名正常成人(男100名,女100名)进行颅脑扫描,利用电子计算机三维重建程序立体地显示颅底外面的卵圆孔、棘孔、颈动脉管外口、破裂孔、茎乳孔、枕骨大孔,并观察其形态和测出其内径及其性差。     

Le Fort Ⅰ型截骨术定位平面的应用解剖学研究

目的:研究Le Fort Ⅰ型截骨术与上颌牙根尖的关系,为临床合理制订截骨平面提供解剖学依据.方法:选择上颌牙槽清晰或出土后仍有牙保留的颅骨,在颅骨梨状孔下缘至上颌结节作一连线作为模拟Le Fort Ⅰ型术式截骨水平,以上颌牙槽缘为标志,用游标卡尺测量每侧上颌各牙的牙槽缘至上述模拟截骨水平的距离及牙槽缘至各牙根尖端的长度,然后计算出上颌各牙根尖至Le Fort Ⅰ型术式截骨线的距离.结果:上颌各牙相对的牙槽缘至Le Fort Ⅰ型术式截骨线的距离,从中切牙至第二磨牙逐渐缩小,右侧中切牙为21.09±1.53 mm,左侧中切牙为20.96±1.64mm,右侧第二磨牙为14.94±1.52 mm,左侧第二磨牙为14.95±1.59mm;上颌各牙根尖至LeFort Ⅰ型术式截骨水平的距离,从中切牙至第二磨牙也逐渐缩小,而两侧尖牙牙根尖距离LeFort Ⅰ型术式截骨线的距离右侧为4.49±1.74mm,左倒为4.69±2.14mm,第二磨牙牙根尖距离Le Fort Ⅰ型术式截骨线的距离右侧为4.65±1.63mm,左侧为4.49±1.89,两侧尖牙牙根尖和第二磨牙牙根尖至LeFort Ⅰ型术式截骨水平的距离均比较接近.结论:上颌各牙根尖至LeFort Ⅰ型术式截骨线的距离均在4mm以上,根据前牙中尖牙牙根尖的位置和后牙中第二磨牙牙根尖的位置,LeFort Ⅰ型术式截骨线水平在13、23(3|3)根尖及27、27(7|7)根尖上方4mm以上,按此平面作截骨水平较为安全,不易损伤牙根.     

主胰管在胰体尾切除术中的应用解剖学研究

目的:为行胰腺体尾部切除时寻找主胰管减少胰瘘提供解剖学资料。方法:解剖观测胰腺标本、胰腺动脉与胰管联合铸型标本各10例。结果:主胰管起于胰尾的中部,在胰颈、体、尾部与上缘之间的距离分别为(7.51±1.06)mm,(10.98±1.81)mm,(8.44±1.72)mm。胰腺各横断面上主胰管的后距,胰颈处为(2.15±0.61)mm,距胰颈1cm处的胰体部为(5.84±1.11)mm,2cm处为(6.12±0.93)mm,胰尾处为(7.44±0.86)mm。铸型标本中脾动脉有9例走行于胰腺上缘,与主胰管的距离在胰颈左侧2 cm处为(9.37±1.05)mm,胰体部中点处为(11.72±1.63)mm,胰尾处为(8.98±1.01)mm,脾动脉的位置变异1例。结论:在胰颈左侧2cm处按自下而上、由前往后的顺序分离并结扎主胰管可减少胰体尾切除术后胰瘘的发生。     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).