日常胎动记录图预测和评估脐带绕颈胎儿宫内安危的价值研究

背景　胎动（FM）是唯一依赖孕妇自我评估的主观性指标，却可客观反映胎儿宫内安全情况；如何将FM量化并使其成为一个相对客观的评价指标一直是产科医师研究和关注的焦点。目的　通过应用日常胎动记录图（DFMC）预测和评估脐带绕颈胎儿的宫内安危。方法　回顾性选取2010年1月-2016年1月在浙江衢化医院住院分娩的足月孕妇100例，分娩前B超和分娩后临床均证实胎儿脐带绕颈。分析孕妇分娩前24 h DFMC，并根据FM情况预测胎儿宫内是否安全：FM规律定义为宫内安全；FM异常、减少或消失均定义为宫内不安全。收集孕妇一般资料，包括年龄、孕周、超声下脐动脉收缩期与舒张期血流比值（S/D值）、羊水指数（AFI），同时行临产前24 h无应激试验（NST）并予以改良Fischer评分法评分，采集分娩后围生儿结局情况、分娩方式（自然阴道、剖宫产、产钳助产）。根据分娩后围生儿结局分为胎儿宫内安全组（44例）和胎儿宫内不安全组（56例），采用多因素Logistic逐步回归分析探究脐带绕颈胎儿宫内安全的影响因素。结果　两组S/D值、脐带绕颈周数、FM、改良Fischer评分法评分、分娩方式比较，差异均有统计学意义（P<0.05）。多因素Logistic逐步回归分析结果显示，FM和分娩方式是脐带绕颈胎儿宫内安危的影响因素（P<0.05）。DFMC预测自然分娩的脐带绕颈胎儿宫内安全的灵敏度为86.5%，特异度为90.0%，约登指数为0.77；DFMC预测剖宫产的脐带绕颈胎儿宫内安全的灵敏度为66.7%，特异度为94.6%，约登指数为0.61。FM异常、减少或消失者剖宫产比例为87.5%（35/40）。结论　DFMC可以有效预测和评价脐带绕颈胎儿宫内安危，同时亦可为胎儿脐带绕颈的孕妇分娩方式的选择提供有限的临床依据。     

The Role Of Electro-Physiological Tests in the Diagnosis of Non-Organic Hearing Loss

Today it is possible, by the use of newly developed tests, to diagnose cases of non-organic hearing loss with reasonable certainty. Having once decided that there may be non-organic elements, it is useful to supplement routine pure-tone and speech audiometry with a neurophysiological test like an ERA by means of which the auditory threshold can be established without the patients subjective judgement. A hearing loss which is apparent by routine pure-tone audiometry, but which is not evident after ERA is almost certainly non-organic, although confirmation of this state of affairs by other reliable tests is advisable. Measurement of the acoustic reflex thresholds and delayed speech feedback tests are both useful in this respect and rarely cause any confusion, except in some cases of true hearing loss in strongly recruiting ears.     

Biology of tooth replacement in amniotes

Tooth replacement is a common trait to most vertebrates, including mammals. Mammals, however, have lost the capacity for continuous tooth renewal seen in most other vertebrates, and typically have only 1–2 generations of teeth. Here, we review the mechanisms of tooth replacement in reptiles and mammals, and discuss in detail the current and historical theories on control of timing and pattern of tooth replacement and development.     

聚丁二酸丁二醇酯浸提液对人外周血单核细胞的体外遗传毒性

目的： 研究生物可降解材料聚丁二酸丁二醇酯[poly(butylene succinate)，PBS]浸提液对人外周血单核细胞(peripheral blood mononuclear cells，PBMCs)的体外遗传毒性。方法：参照GB/T 16886-2005标准制备PBS浸提液。采用MTT试验评价不同浓度(200、100、50、25、12.5、6.25、3.125 mg/mL) PBS浸提液对PBMCs的细胞毒性；并进行染色体畸变试验和微核试验评价其体外遗传毒性。同时设溶剂RPMI-1640和医用级左旋聚乳酸(L-polylactide，L-PLA)对照组。结果：PBS浸提液对PBMCs的细胞毒性与溶剂对照和L-PLA比较差异均无统计学意义(P＞0.05)；200 mg/mL PBS浸提液在代谢活化和非代谢活化条件下与PBMCs共培养48 h后染色体畸变均为阴性；200 mg/mL PBS浸提液诱发的微核细胞数与溶剂对照组和L-PLA组相比差异均无统计学意义(P＞0.05)。结论：在本试验条件下，生物可降解材料PBS浸提液在体外对PBMCs无遗传毒性，其影响与医用级L-PLA相当。     

Inhibitory potential of the leaves and berries of Myrtus communis L. (myrtle) against enzymes linked to neurodegenerative diseases and their antioxidant actions

The dichloromethane (DCM), acetone, ethyl acetate and methanol extracts of the leaves and berries of Myrtus communis L. were screened against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and tyrosinase (TYRO), the enzymes linked to neurodegenerative diseases, at 200 μg ml^{? 1}. Antioxidant activity was tested using radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and N,N- dimethyl-p-phenylenediamine (DMPD) radicals, metal chelation capacity, ferric-reducing antioxidant power (FRAP) and phosphomolybdenum-reducing antioxidant power (PRAP) assays. Total phenol and flavonoid quantification of the extracts was calculated spectrophotometrically. The extracts showed a moderate AChE (17.49 ± 3.99% to 43.15 ± 1.55%) and TYRO inhibition (4.48 ± 1.50% to 40.53 ± 0.47%). The leaf extracts were ineffective against BChE, while the berry extracts displayed inhibition between 21.83 ± 3.82% and 36.80 ± 2.00%. The polar extracts exerted remarkable scavenging effect against DPPH and DMPD and also in the FRAP assay, where the DCM extract of the berries had the best metal chelation capacity (79.29 ± 1.14%). This is the first study that demonstrates in vitro neuroprotective effects of myrtle.     

射波刀验收检测方法及思考

介绍新一代四维放射外科治疗设备射波刀（Cyberknife）的组成、主要参数及检测方法。射波刀以其亚毫米级的治疗精度,机械臂6个方向的运动维度,较常规放疗设备具有较大优势。笔者通过对射波刀实际的验收检测,总结其验收方法,并结合实际情况引发对射波刀验收检测工作的思考。     

Development and standardization of single and double dichotic digit tests in the Malay language

Single and double dichotic digit tests in Malay language were developed and standardized as an initial attempt to incorporate tests of auditory processing within the scope of audiology practice in Malaysia. Normative data under free recall, directed right-ear first, and directed left-ear first listening conditions were determined using 120 Malay children between the ages of 6 and 11 years old with normal hearing and normal academic performance. Test-retest reliability was assessed in 15 of the study subjects. In general, the double dichotic digit test produced greater differences in scores between age groups, and a greater right-ear advantage than the single dichotic digit test. In addition, the double dichotic digit test also had higher test-retest reliability. These findings suggest the double dichotic digit test is more clinically applicable.     

佛山市禅城区中小学生肺结核感染和患病现况

目的了解佛山市禅城区中小学生结核菌感染和肺结核患病现况,为主管部门提供学校结核病防治工作决策依据。方法整群抽取佛山市禅城区中小学新生19 685名进行PPD试验,检查结果采用SPSS 16.0统计分析。结果佛山市中小学生PPD总体阳性率为52.0%,强阳性率3.6%,发现5例活动性肺结核病人,患病率为28.76/105。初中学生PPD阳性4 737例(51.5%),强阳性307例(3.3%);小学生阳性3 689例(45.1%),强阳性311例(3.8%);初中生阳性率低于小学生(χ2=70.36,P<0.01)。受检男生中,阳性4459例(46.1%),强阳性255例(2.6%);女生中,阳性3 967例(51.4%),强阳性363例(4.7%),女生阳性率高于男生(χ2=124.39,P<0.01)。有肺结核患者的学校PPD阳性和强阳性检出率高于无肺结核患者的学校(χ2=31.76,P<0.01),患者所在班级PPD总体阳性率高于无患者的班级(χ2=9.28,P=0.01)。结论佛山市中小学学生结核菌感染率和活动性肺结核患病率较高,初中生、女生易感,患者所在班级和学校结核菌感染率较高。因此,要针对重点人群,加强佛山市中小学生结核病防治工作。     

C-terminal Src kinase (CSK) and CSK-homologous kinase (CHK)—endogenous negative regulators of Src-family protein kinases

C-terminal Src kinase (CSK) and CSK-homologous kinase (CHK) are endogenous inhibitors of the Src-family protein tyrosine kinases (SFKs). Since constitutive activation of SFKs contributes to cancer formation and progression, to prevent excessive activation of SFKs, their activity in normal cells is kept at the basal level by CSK and CHK. CSK and CHK inactivate SFKs by specifically phosphorylating a consensus tyrosine (called Y_T) near their C-termini. Upon phosphorylation, the phospho-Y_T engages in intramolecular interactions that lock the SFK molecule in an inactive conformation. SFKs are anchored to the plasma membrane, while CSK and CHK are localized predominantly in the cytosol. To inhibit SFKs, CSK and CHK need to translocate to the plasma membrane. Recruitment of CSK and CHK to the plasma membrane is mediated by the binding of their SH2, SH3 and/or kinase domains to specific transmembrane proteins, G-proteins and adaptor proteins located near the plasma membrane. For CSK, membrane recruitment often accompanies activation. CSK and CHK employ two types of direct interactions with SFKs to achieve efficient Y_T phosphorylation: (i) short-range interactions involving binding of the active sites of CSK and CHK to specific residues near Y_T, (ii) long-range non-catalytic interactions involving binding of SFKs to motifs located distally from the active sites of CSK and CHK. The interactions between CSK and SFKs are transient in nature. Unlike CSK, CHK binds tightly to SFKs to form stable protein complexes. The binding is non-catalytic as it is independent of Y_T. More importantly, the tight binding alone is sufficient to completely inhibit SFKs. This non-catalytic inhibitory binding represents a novel mechanism employed by CHK to inhibit SFKs. Given that SFKs are implicated in cancer development, compounds mimicking the non-catalytic inhibitory mechanism of CHK are potential anti-cancer therapeutics.