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51.
The progesterone production of the granulosa cells of the cumulus– oocyte complex correlates very well with the cleavagepotential of embryos in an IVF system. The method is simpleand can be easily performed by any laboratory associated withIVF. Furthermore, high intratubal progesterone levels in theimmediate post-ovulatory period are probably important in prolongingthe intra-ampullary residence of the oocyte or embryo untilthe uterine endometnum is optimal for implantation.  相似文献   
52.
The amyloid precursor protein (APP) gives rise to beta-amyloid peptides, which are the main constituents of senile plaques in brains of Alzheimer's disease (AD) patients. The generation of beta-amyloid peptides requires the enzymatic activity of the beta-site APP-cleaving enzyme 1 (BACE1). BACE1 is primarily expressed by neurons and increased BACE1 protein concentrations and enzymatic activities have been reported in the brains of AD patients. However, there is accumulating evidence that, in addition to neurons, reactive astrocytes are capable of expressing BACE1 and, therefore, may contribute to beta-amyloid plaque formation. This suggests that conditions accompanied by chronic astrocyte activation may contribute to developing AD. Non-amyloidogenic processing of the APP can be stimulated by phorbol esters (PEs) and by intracellular diacylglycerol (DAG) generation. This led to the hypothesis that classical and novel protein kinase Cs (PKCs), which are activated by DAG/PEs, regulate APP processing. However, in addition to PKCs, there are other DAG/PE receptors present in neurons which may participate in the modulation of APP processing. Munc13-1, a presynaptic protein with an essential role in synaptic vesicle priming, represents such an alternative target of the DAG second messenger pathway. Using Munc13-1 knock-out mice and human neuroblastoma cells transfected with wild-type and mutant Munc13-1 constructs it was demonstrated that Munc13-1 acts independently of and in parallel with PKC to modulate APP metabolism. Therefore, agonists specific for the Munc13-1 C1-domain or small molecules mimicking the function of the endogenous Munc13-1 activator RIM1 may prove useful to shift APP processing towards the non-amyloidogenic pathway.  相似文献   
53.
目的:探讨肝外胆管癌的诊断和治疗的体会。方法:回顾性总结手术治疗的32例肝外胆管癌的临床资料、手术方式、手术并发症及生存率,并复习相关文献资料。结果:本组病例获根冶性切除14例,姑息切除2例,胆道引流术16例;手术并发症10例(31.3%),手术死亡1例(3.1%)。其中22例获定期随访,存活一年以上的有12例(12/22),至今存活8例。结论:早期诊断、正确的评估、合理的术式选择能提高疗效。降低手术并发症及死亡率。  相似文献   
54.
目的探讨婴儿脑损伤筛查专科门诊在早期发现婴儿脑损伤的作用以及神经发育疗法治疗脑损伤的效果。方法采用专科门诊筛查,早期发现脑损伤忠儿。对婴儿脑损伤进行早期诊断和早期综合康复治疗,以临床疗效评估。结果专科门诊对早期发现婴儿脑损伤有意义,88.1%的患儿由门诊筛查发现而被诊断,筛查中应着重注意小婴儿肌张力改变(48%)和运动发育落后(35%),脑损伤中不明原因占18%,1岁以内脑损伤诊断以中枢性发育障碍(89%)、运动落后(11%)为主,治疗以神经发育疗法为主的综合方法,20d一疗程,108例1岁以下脑损伤忠儿治疗效果:显效46.2%,好转47.2%,无效6.6%,总有效率为93.4%,6mo以下疗效显著高于6mo以上脑损伤忠儿。结论婴儿脑损伤专科门诊定期筛查能够早期发现患儿,CDD和MD作为婴儿脑损伤早期诊断的名称是可取的,治疗以神经发育疗法为主,治疗愈早,效果愈好,婴儿脑损伤早期诊断和早期医学干预方法可以在医疗保健机构推广和应用。  相似文献   
55.
本文根据34例电击伤临床资料,分析早期处理与病人全身情况、局部损伤愈合以及并发症的关系.并讨论间生态组织的处理原则.结果表明:伤后1天内与伤后3天以上就诊的病人比较,前者全身情况良好,创面感染率低,局部损伤用皮瓣或(和)皮片覆盖效果满意,并发症及截肢率均较低  相似文献   
56.
Single photon emission computerized tomography (SPECT) is now widely used as one of the tools in evaluating cerebral blood flow (CBF). The authors report the CBF changes in childhood hydrocephalus. Five pediatric cases studied by 123I-IM SPECT in children are presented. The authors counted radioactivities both in early and delayed images in each patient, and calculated the reabsorption ratio (RR). Two negative-RR cases and three positive-RR cases were found. All of the negative-RR patients had a poor prognosis, while all of the positive-RR patients had a favorable outcome.  相似文献   
57.
This qualitative study that allowed children to be the dominant voice examined children's stories of hope. Twenty-nine kindergarten children through to third graders were interviewed using familiar school items: story board, pictures, puppets, and so on. One elementary school, located in a large southwestern metropolitan city, was selected for this study. Data was coded and prominent themes emerged illustrating that children are much more moral than many adults give them credit for. Approximately one-half of the stories shared focused not on the children's wants or “hopes”, but on others - classmates, friends, family, or extended relatives. The findings support research that highlights the issues of care, concern, and compassion that are a priority for young children.  相似文献   
58.
目的了解儿童及少年期情感障碍和精神分裂症的临床特征.方法收集1984年至1999年之间在本院就诊患者中符合DSM-Ⅲ情感障碍和精神分裂症诊断的儿童及少年期首次发作病例64例,年龄5~17岁.入组时进行基线评定,然后长期随访.至随访结束,对两组疾病进行对照分析.结果58例(91%)完成随访,平均随访时间12.4年.儿童少年期入组诊断为情感障碍者36例,至成年随访结束时,92%诊断为情感障碍,8%诊断为精神分裂症;儿童少年期入组诊断为精神分裂症者22例,至成年随访结束时,32%诊断为情感障碍,68%诊断为精神分裂症.儿童少年期情感障碍患者在成年期诊断为精神分裂症者明显高于精神分裂症患者修改诊断为情感障碍(χ^2=22.852,P<0.001).儿童少年期精神障碍至成年期的诊断一致性较低(Kappa=0.62).儿童及少年期发作的情感障碍与精神分裂症比较,起病年龄低、发作次数少、社会关系良好和较好的社会功能.情感障碍的精神症状多与精神分裂症重叠,但精神分裂症出现频率较高的情感不协调、注意力分散、关系妄想、情感迟钝、被洞悉感等症状,在情感障碍患者中始终未存在.结论儿童及少年期的情感障碍在症状学上与精神分裂症有许多相似之处,是导致误诊的重要原因.但儿童少年期精神分裂症存在的一些核心症状可能是两者鉴别诊断的症状学指标.  相似文献   
59.
梅军 《安徽医学》2004,25(1):33-35
目的 了解早、中期胃癌的临床、胃镜和病理学特征。方法 回顾性分析我院 11年中经外科手术和病理诊断的 75例早、中期胃癌患者的临床、胃镜、外科手术和病理等方面资料。结果 早、中期胃癌临床表现无特征性 ,男女之比为 2 .41∶1,以 61~ 70岁最多 ,胃窦是其好发部位 ,病理组织学以管状腺癌为多 ,胃镜误诊率是 12 .86%,淋巴转移率是 2 5 .3 3 %。结论 早、中期胃癌有明显的好发年龄和好发部位 ,以管状腺癌为多 ,胃镜误诊的主要原因是不能鉴别病变的良、恶性和准确判断病变量 ,影响淋巴转移的因素是浸润深度、广度、肿瘤大小和年龄 ,而与性别、组织学的分化程度无明显关系。  相似文献   
60.
The feasibility of using in vivo autofluorescence for the diagnosis of skin cancer was evaluated. In vivo fluorescence measurements were performed on healthy human volunteers, and patients with different types of benign and malignant skin tumours. Fluorescence spectra as well as fluorescence images were acquired. The excitation-emission matrix of normal skin (n=3) showed a broad peak at the shortest excitation wavelength (365 nm) and at 440 nm fluorescence wavelength, smoothly decreasing towards longer excitation and fluorescence wavelengths. Non-melanoma skin tumours (n=31) and control skin excited with 375 nm showed a broad fluorescence band from 400 to 700 nm, peaking around 436 nm. No significant differences in measurements between tumours and the corresponding control sites were found. A large spatial variation in the fluorescence intensity was observed both in the tumours and in the control sites. Standard deviations found ranged from 0.15 to 1.5 times the mean fluorescence. Fluorescence images, excited with 375 nm and taken with an image intensified CCD camera, on eight malignant melanomas and eight benign pigmented lesions did not indicate any fluorescence intensity distribution specific to the malignancy of the lesion. Neither the shape of the fluorescence spectra, nor the spatial distribution of the fluorescence intensity showed any signature specific to the histopathological nature of the lesions investigated. Optical diagnostics of skin tumours using the autofluorescence does not seem to be feasible at the present time.  相似文献   
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