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41.
Angiogenesis is an important prognostic factor in infiltrating ductal carcinoma (IDC). Vascular endothelial growth factor (VEGF) stimulates angiogenesis in vivo. VEGF expression has been correlated with high vascularity in IDC. However, little is known about the prognostic significance of microvessel density (MVD) and its correlation with the expression of VEGF in infiltrating lobular carcinoma (ILC). We analyzed tumor samples from 51 patients with primary classic ILC to determine the relationship between tumoral MVD and VEGF expression. Cases of pleomorphic lobular carcinoma and tubulolobular carcinoma were excluded. Five-micron thick sections obtained from formalin-fixed, paraffin-embedded tissue blocks were immunostained with antibodies to factor VIII-related antigen (Dako, Carpenteria, CA) and VEGF (Calbiochem, Boston, MA). The former was used for MVD analysis. The vessel counts from the three most vascular fields (x200 magnification) were recorded and the highest of the vessel counts of the three fields was designated as the MVD. The intensity of VEGF staining and the proportion of cells staining were scored. Both the vessel counts and the scoring of VEGF staining were evaluated by two independent pathologists. The Student's t-test and Wilcoxon rank sum test were used to compare mean MVD and VEGF scores according to various clinical and pathologic features. All significance tests were two-sided with an alpha-level of 0.05. There was good correlation between the MVD of each observer (correlation coefficient 0.775, p < 0.001). There was no correlation of MVD or VEGF score with the size or stage of the tumor. In addition, the MVD or VEGF score was not significantly different between axillary lymph node-positive cases and node-negative cases, between patients with recurrence and those without, and between patients who survived and those who died of disease. There was, however, a weak negative correlation between the MVD and VEGF expression (Spearman correlation coefficient -0.08). Neither MVD or VEGF immunoscore were associated with tumor recurrence or vital status in patients with ILC. The absence of a statistically significant positive correlation between MVD and VEGF expression suggests that other factors may play a more important role in the angiogenesis of ILC.  相似文献   
42.
Our earlier efforts to document the cortical connections of the ventral premotor cortex (PMv) revealed dense connections with a field rostral and lateral to PMv, an area we called the frontal rostral field (FR). Here, we present data collected in FR using electrophysiological and anatomical methods. Results show that FR contains an isolated motor representation of the forelimb that can be differentiated from PMv based on current thresholds and latencies to evoke electromyographic activity using intracortical microstimulation techniques. In addition, FR has a different pattern of cortical connections compared with PMv. Together, these data support that FR is an additional, previously undescribed motor-related area in squirrel monkeys.  相似文献   
43.
游离黏膜组织重建尿道治疗复杂性尿道狭窄的临床研究   总被引:11,自引:0,他引:11  
目的 探讨利用游离黏膜一期尿道成形治疗复杂性尿道狭窄或闭锁的疗效。方法 2000年8月至2004年7月采用2种游离黏膜一期尿道成形术治疗73例复杂性尿道狭窄。术前42例已行耻骨上膀胱造瘘,余31例最大尿流率1.2~6.5ml/s。用游离结肠黏膜(n=22)重建尿道长10~18cm,平均13cm;用口腔黏膜(n=51)重建尿道长3~11cm,平均5cm。术后随访分别行逆行尿道造影及尿流率,部分患者行尿道镜检查。结果随访2~48个月,平均19个月。术后排尿通畅67例(91.8%)。发生再次狭窄4例,其中结肠黏膜重建者1例,口腔黏膜重建者3例;排尿欠畅2例,定期行尿道扩张;尿道皮肤瘘2例;结肠腹壁瘘1例。1例结肠黏膜重建尿道者术后47个月移植物活检示结肠黏膜的组织形态学基本无变化。结论口腔与结肠黏膜均可作为较理想的尿道替代物,口腔黏膜较适合狭窄段不长的尿道修复,结肠黏膜较适合复杂性超长段尿道狭窄或缺损的治疗。  相似文献   
44.
输血和大多数临床治疗技术一样,存在着一定的风险,输血风险主要由免疫性输血风险和输血感染性风险两大类相关的安全问题。20世纪80年代开始,由于艾滋病的发现迫使输血相关的安全问题更进一步成为公众关注的焦点。随着输血用血医学的不断发展,在已经获得很好治疗效果的同时,如何更加科学的安全用血是挑战当今公共卫生事业发展的一项大课题。  相似文献   
45.
OBJECTIVE: To determine the prevalence of intestinal parasitosis in one rural village and one urban centre in North Central Nigeria. METHODS: A total of 111 single stool specimens from all the volunteered rural dwellers and 93 specimens from randomly selected urban dwellers were examined using Formol-ether and modified Ziehl-Neelsen techniques; during the months of June and July 2005. A questionnaire was completed for each subject and the nutritional status of the adults was assessed using the anthropometric measurements (weight and height for age and Biomass index). RESULTS: The results suggest very high prevalence rates of intestinal parasitosis of 72.1% and 69.9% for the rural and urban populations respectively. All the age groups were infected. The males in the rural area had a prevalence of 69.2% as against 74.6% in females (P>0.05); while in the urban area, the males were more significantly infected (77.4%) compared with the females with 66.1% (P< 0.05). Those with normal BMI (18.5-24.9 kg/m2) had the highest prevalence of 79.3% and 72.4% for the rural and urban populations respectively. The prevalence of the parasites in the rural and urban populations respectively were: Entamoeba coli (16.2% and 9.7%); E. histolytica (18.9% and 18.3%); E. hartmani (1.8% ad 0.0%); Endolimax nana (16.2% and 18.3%); Iodamoeba butschlii (0.0% and 1.1%); Giardia lamblia (7.2% and 4.3%); Schistosoma mansoni (9.9% and 0.0%); Strongyloides stercoralis (0.9% and 0.0%); Hookworm (4.5% and 5.4%); Ascaris lumbricoides (1.8% and 0.0%); Enterobius vermicularis (0.0% and 1.1%); Cryptosporidium parvum (29.7% and 19.4%); and Enterocytozoon bieneusi/Encephalitozoon intestinalis (39.6% and 47.3%). Polyparasitism was recorded in 48.6% of the rural subjects and 36.6% of the urban subjects. CONCLUSION: The study has shown a very high prevalence of intestinal parasitosis in both the rural and urban populations and that C. parvum and E. bieneusi/E. intestinalis are harboured by apparently healthy individuals.  相似文献   
46.
目的研究全反式维甲酸(ATRA)及联合应用神经营养因子(BDNF,GDNF)对体外培养的神经干细胞(NSCs)分化的影响。方法取新生SD大鼠的前脑室下带(SVZ)区,按NSCs的常规培养方法分离、培养。用免疫细胞化学法鉴定巢蛋白(nestin)、微管相关蛋白-2(MAP-2)、胶质原纤维酸性蛋白(GFAP)的表达,以此来观察ATRA、BDNF、GDNF单独或联合应用对次代神经球细胞分化的作用。结果原代及次代神经球均显示nestin阳性,并可分化为MAP-2阳性神经元样细胞及GFAP阳性胶质细胞样细胞。1μmol/LATRA可促进NSCs分化为MAP-2阳性细胞的比例达(29.14&#177;5.00)%,显著高于对照组的(7.19&#177;1.21)%,差异有高度统计学意义(P〈0.001)。ATRA联合应用10ng/ml的BDNF或GDNF,与单独使用ATRA比较,并不显著提高NSCs分化为MAP-2阳性细胞的比例。结论ATRA可促进神经干细胞向神经元方向分化,ATRA联合应用BDNF或GDNF无明显的协同作用。  相似文献   
47.
目的:研究不同生长期当归根部生物量及有效成分的动态变化规律。方法:采收不同生长期当归27批,并测定其根部生物量;采用气相色谱-质谱联用技术(GC-MS)测定当归挥发油中Z-藁本内酯与正丁烯基苯酞的含量。结果:GC-MS法测得27批不同生长期当归挥发油中正丁烯基苯酞、Z-藁本内酯的平均含量分别占总油的1%和40%以上,其含量在不同生长期中变化较大。结论:当归中Z-藁本内酯与正丁烯基苯酞含量与其生长周期密切相关。  相似文献   
48.
OBJECTIVES--Whereas serovars A, B, Ba and C of Chlamydia trachomatis are usually associated with trachoma, two of these serovars (Ba and C) are occasionally observed in urogenital infections. Variation in the gene encoding the major outer membrane protein (MOMP) was explored to distinguish urogenital from trachoma specimens of the same serovar. METHODS--A large portion of the MOMP gene was amplified by nested PCR directly from clinical samples from trachoma or urogenital infection and the serovar of the infecting C trachomatis was determined by restriction fragment length polymorphism (RFLP). Amplified DNA from trachoma serovars B, Ba and C and from urogenital serovars Ba, C, D and E was sequenced by the dideoxy chain termination method. RESULTS--While almost identical in variable segment (VS)I, three urogenital Ba samples differed from all trachoma B and Ba samples at eight nucleotides including two sites which changed amino acids in the constant region upstream of VSI. An identical sequence in this region was observed for the reference urogenital D serovar. Variation in this same region upstream of VSI also distinguished 40% of serovar D samples from prototype D including three that were sequenced. Two urogenital C differed from trachoma C samples at four sites that changed the MOMP amino acid sequence including two changes in the constant region between VSII and III and single changes in VSII and III. On the basis of these sequence determinations, RFLP was predicted which allowed extension of these observations to 20 other urogenital Ba, 12 trachoma B or Ba, seven variant D, 12 D, four urogenital C and three trachoma C samples without further sequencing. CONCLUSION--Urogenital Ba and C samples have VSI or II and III sequences identical or very similar to trachoma strains of the same serovar, but resemble more closely other serovars in the constant regions. Urogenital serovar D samples can also be divided into two genotypes on the basis of sequence differences in the constant region preceding VSI.  相似文献   
49.

Introduction

Regenerative peripheral nerve interfaces (RPNIs) are biological constructs which amplify neural signals and have shown long-term stability in rat models. Real-time control of a neuroprosthesis in rat models has not yet been demonstrated. The purpose of this study was to: a) design and validate a system for translating electromyography (EMG) signals from an RPNI in a rat model into real-time control of a neuroprosthetic hand, and; b) use the system to demonstrate RPNI proportional neuroprosthesis control.

Methods

Animals were randomly assigned to three experimental groups: (1) Control; (2) Denervated, and; (3) RPNI. In the RPNI group, the extensor digitorum longus (EDL) muscle was dissected free, denervated, transferred to the lateral thigh and neurotized with the residual end of the transected common peroneal nerve. Rats received tactile stimuli to the hind-limb via monofilaments, and electrodes were used to record EMG. Signals were filtered, rectified and integrated using a moving sample window. Processed EMG signals (iEMG) from RPNIs were validated against Control and Denervated group outputs.

Results

Voluntary reflexive rat movements produced signaling that activated the prosthesis in both the Control and RPNI groups, but produced no activation in the Denervated group. Signal-to-Noise ratio between hind-limb movement and resting iEMG was 3.55 for Controls and 3.81 for RPNIs. Both Control and RPNI groups exhibited a logarithmic iEMG increase with increased monofilament pressure, allowing graded prosthetic hand speed control (R2?=?0.758 and R2?=?0.802, respectively).

Conclusion

EMG signals were successfully acquired from RPNIs and translated into real-time neuroprosthetic control. Signal contamination from muscles adjacent to the RPNI was minimal. RPNI constructs provided reliable proportional prosthetic hand control.
  相似文献   
50.
AIDS and Behavior - Economic vulnerability is often reported to underlie involvement in sex work among female sex workers (FSW), but may also create urgency in women’s work, limiting...  相似文献   
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