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41.
本文报道3-50岁214例心导纳微分环(CADL)和肺导纳微分环(PADL)最大向量振幅及方位正常值,结果随增龄变化振幅递减,方位递增,多数男>女,部分组间有差异。48例左向右分流先心病环体最大向量与肺动脉压之间呈平行关系,并探讨其临床意义。  相似文献   
42.
A 13-year-old boy had complained of an asymptomatic swelling in the anterior maxilla for approximately 4 years. The patient reported no local trauma. The intra-oral examination revealed an exophytic lesion in the incisive papilla between the maxillary central and lateral incisor teeth. The radiographies detected no significant findings. Histopathologically, the lesion showed a dense fibrous tissue above the overlying mucosa. Bone ossification lay beneath a partially hypertrophic cartilage showing occasionally pleomorphic chondrocytes. Because of its microscopic aspects, heterotopic ossification may be mistaken for chondrosarcoma or other conditions involving periosteum, such as parosteal osteosarcoma. A case of heterotopic ossification in the anterior maxilla is presented, and clinicopathologic similarities with other osteochondromatous lesions are discussed.  相似文献   
43.
目的 明确妇科腹腔内出血的临床特征 ,以减少误诊。方法 对我院 1999年 1月至 2 0 0 1年 12月以妇科腹腔内出血收治的 186例患者的临床资料进行回顾性分析。结果  186例病人包括 5种疾病 ,其中异位妊娠、卵巢破裂、出血性输卵管炎及腹部卒中易相互误诊。本资料 15 0例经手术止血 ,36例经保守治疗成功 ,无 1例死亡。结论 详细询问病史 ,血HCG检测和阴道B超检查 ,后穹窿或腹腔穿刺是简便而重要的诊断手段。  相似文献   
44.
目的:利用粒细胞-巨噬细胞集落刺激因子(GM-CSF)作为基因佐剂,提高东部马脑炎病毒E2基因重组质粒的免疫效果.方法:分别扩增E2基因与GM-CSF基因,连接进入含有内部核糖体插入位点(IRES)的真核表达载体中,构建共表达质粒.Lipofectamine2000介导转染真核细胞BHK-21,反转录PCR检测E2和GM-CSF两个基因的转录,Western印迹法和间接免疫荧光法(IFA)检测细胞内E2基因表达产物的抗原性.通过肌肉注射免疫BALB/c小鼠,IFA法测定血清抗体效价,FACS测定免疫小鼠脾细胞中CD4 /CD8 淋巴细胞构成比,初步观察共表达质粒的免疫原性.结果:经酶切鉴定与序列测定证明重组共表达质粒中含有E2和GM-CSF两个基因且序列正确.转染细胞的反转录PCR可见E2和GM-CSF两个基因的转录.Western印迹结果可见转染细胞的裂解液在相对分子质量50 000位置有特异性条带.将转染细胞制成荧光抗原片,经IFA检测可见胞浆中出现特异荧光.免疫小鼠的最高血清抗体效价为1:160,但细胞免疫未观察到明显的提高.结论:构建的共表达质粒pE2-IRES-mGM-CSF具有良好的免疫原性,能有效刺激小鼠特异性体液免疫应答,提高了E2基因重组质粒诱导的血清抗体效价.  相似文献   
45.
The diagnosis of idiopathic Parkinson's disease (PD) can be achieved with high degrees of accuracy in cases with full expression of classical clinical features. However, diagnostic uncertainty remains in early disease with subtle or ambiguous signs. Functional imaging has been suggested to increase the diagnostic yield in parkinsonian syndromes with uncertain clinical classification. Loss of striatal dopamine nerve terminal function, a hallmark of neurodegenerative Parkinsonism, is strongly related to decreases of dopamine transporter (DAT) density, which can be measured by single photon emission computed tomography (SPECT). The use of DAT‐SPECT facilitates the differential diagnosis in patients with isolated tremor symptoms not fulfilling PD or essential tremor criteria, drug‐induced, psychogenic and vascular Parkinsonism as well as dementia when associated with Parkinsonism. This review addresses the value of DAT‐SPECT in early differential diagnosis, and its potential as a screening tool for subjects at risk of developing PD as well as issues around the assessment of disease progression. © 2007 Movement Disorder Society  相似文献   
46.
利用变分原理,从不同角度,讨论了随机微分方程特征问题特征值的性质,给出了其期望值的两个上界估计式。  相似文献   
47.
本文测定恶性、炎性和肝硬化3组胸腹水中的总唾液酸(TotalSialic Acid TSA)和脂质结合唾液酸(Lipid-bound Sialic Acid LSA)含量,结果表明恶性组和炎性组的 TSA 和 LSA 明显高于肝硬化组,但恶性组和炎性组的 TSA 和 LSA 则无明显差异。恶性、炎性和肝硬化组的 TSA 值分别为499.52±183.98mg/L、508.68±208.79mg/L 和117.71±70.46mg/L;LSA则分别为146.28±103.62mg/L、115.26±72.13mg/L 和58.90±35.46mg/L。以肝硬化组的 TSA+2SD 作为恶性组和肝硬化组的鉴别值,其敏感性为88%,特异性为90.47%,有效性为89.13%。LSA 则无鉴别价值。  相似文献   
48.
Bedu-Addo  Frank K.  Tang  P.  Xu  Y.  Huang  Leaf 《Pharmaceutical research》1996,13(5):710-717
Purpose. The purpose of this study was to investigate polyethyleneglycol(PEG)-phosphatidylethanolamine(PE) conjugate interaction with phospholipid bilayers, in an attempt to explain the dependence of liposome circulation time on formulation. Methods. Differential scanning calorimetry, electron microscopy, dynamic light scattering and NMR were the major methods used in the study. Results. Mixtures of PEG-phospholipid conjugates and phosphatidylcholine existed in three different physical states: a lamellar phase with components exhibiting some miscibility, a lamellar phase with components phase separated, and mixed micelles. Beyond 7 mol% of PEG(l,000–3,000)-dipalmitoyl phosphatidylethanolamine (DPPE), and 11 mol% PEG(5,000)-DPPE in dipalmitoyl phosphatidylcholine (DPPC), a strong tendency towards mixed micelle formation was observed. All concentrations of PEG(12,000)-DPPE and PEG(5,000)-DPPE beyond 8 mol% formed phase separated lamellae with phosphatidylcholine. Decreasing the acyl chain length from C16:0 to C14:0 caused a decrease in tendency towards micelle formation and phase separation. These tendencies increased upon increasing acyl chain length to C18:0. Phase separation was at least partly due to PEG chain-chain interaction. This was supported by an increased fraction of PEG chains exhibiting a fast NMR transverse relaxation in DPPC/PEG(5,000)-DPPE mixtures as compared to that in distearoyl phosphatidylcholine (DSPC)/PEG(5,000)-dioleoyl-PE (DOPE). Conclusions. These phenomena are discussed in relation to both bilayer and steric stabilization of liposomes, and the lack of prolonged circulation with certain formulations is discussed.  相似文献   
49.
The performance of the CELL-DYN 1700® (Abbott Diagnostics, Abbott Park, IL, USA) was evaluated in a tertiary care hospital laboratory using the guidelines proposed by the German Society of Clinical Chemistry. Precision, accuracy, linearity, background counts, and carry-over were satisfactory for all measured standard parameters including haemoglobin concentration, haematocrit, red blood cell count, mean corpuscular volume (MCV), red cell distribution width (RDW), white blood cell count and platelet count. With 259 selected normal and abnormal blood samples the results of the CELL-DYN 1700® (CD1700) compared very well (r > 0.96 for all parameters with exception of RDW) with those obtained with the Bayer Diagnostic H-1 and the Hoffmann-La Roche Cobas Argos systems. This study considered in particular the performance of the CD1700 three-part leucocyte differential. For those samples without instrument-generated suspect flags, the neutrophil and lymphocyte percentages were highly correlated with the results of the H-1 blood cell counter (r = 0.97 and 0.98, respectively) and with manual 400-cell differentials (r = 0.91 and 0.88, respectively). In contrast, the CD1700 mid-fraction which comprised the composite total of mono cytes, eosinophils, basophils and precursor white cells (when present) could not be directly compared to the differentials from the H-1 system or from manual microscopy. For those samples with CD1700 instrument suspect flags, the neutrophil and lymphocyte differential results also compared well with both the H-1 (r = 0.93 and 0.93, respectively) and manual estimates (r = 0.89 and 0.87, respectively). In conclusion, the CD1700 is an accurate haematology analyser for cellular blood counts and three-part leucocyte differentiation.  相似文献   
50.
背景 随着近20余年人工智能(AI)在食管癌领域应用研究的骤增,出现了许多关于该研究的系统、荟萃分析等,但其仅针对AI在该领域应用的单一方面的总结研究,研究人员难以全面了解领域最新发展与研究热点。目的 通过文献计量分析总结AI在食管癌领域的应用,阐明AI在食管癌领域相关研究的进展、热点和新兴趋势。方法检索Web of Science Core Collection(WoSCC)的Science Citation Index Expanded(SCI-E)数据库收录的AI应用于食管癌领域的所有英文文献,检索时间2000-01-01至2022-04-06。应用Microsoft Excel 2019、CiteSpace(5.8R3-64bit)和VOSviewer(1.6.18)对文献进行发文量、国家、作者、机构、共被引和关键词分析。结果 2000—2022年共检索到AI应用于食管癌领域的文献918篇,共计引用文献总量23 490篇。发文趋势:2000—2016年为迟缓期,发文量从6篇增至40篇;2017—2022年为快速增长期,发文量从62篇突增至216篇。60个国家、118家机构、5 ...  相似文献   
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