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101.
J Cheng  T Saku  H Okabe  H Furthmayr 《Cancer》1992,69(11):2631-2640
Tissue samples from 30 patients with adenoid cystic carcinoma and 20 with adenocarcinoma of salivary gland origin were studied by immunohistochemical staining with specific antibodies to the four macromolecules that are present in normal basement membranes: type IV collagen, laminin, heparan sulfate proteoglycan, and entactin. In the adenoid cystic carcinoma samples, the four proteins were localized in different types of extracellular matrices in the tumor, namely pseudocystic spaces, hyaline stroma, and around tumor cell nests. The staining intensity was enhanced by pretreatment with hyaluronidase. The tumor cells of adenoid cystic carcinoma showed a tendency to proliferate with individual cells in contact with the basement membrane and to infiltrate through basement membrane-rich tissues, such as peripheral nerves, blood vessels, and skeletal muscles. In contrast, only circumferential staining of tumor cell nests was obtained in adenocarcinoma samples. The results suggest that adenoid cystic carcinoma is a tumor with affinity for basement membranes, and this basic feature is reflected in its histology and presumably in its biologic behavior. Immunostaining with antibodies to basement membrane proteins appears to be useful for differential diagnosis of some types of these two carcinomas.  相似文献   
102.
九十年代中国人群的膳食与营养状况   总被引:84,自引:6,他引:78  
葛可佑  翟凤英 《营养学报》1995,17(2):123-134
九十年代中国人群的膳食与营养状况葛可佑,翟风英,闽怀成,程列,王青,贾凤梅(中国预防医学科学院营养与食品卫生研究所,北京100050)人群的膳食营养状况在一定程度上可以反映一个国家的经济发展和社会文明程度。世界上大多数发达国家及若干发展中国家都在有计...  相似文献   
103.
电针对大鼠海马兴奋性突触后电位长时程增强的作用   总被引:4,自引:0,他引:4  
目的 观察电针对麻醉状态下正常和东莨菪碱引起的学习记忆减退模型大鼠海马突触EPSP长时程增强(LTP)的作用。方法 引导大鼠海马齿状回颗粒细胞层突触后兴奋性电位群(EPSPs),强直刺激(HFS)大脑皮层前穿质区引起海马突触LTP反应;用东莨菪碱制备学习记忆障碍模型;观察电针大椎和肾俞穴对正常和模型大鼠海马LTP的影响。结果 电针对HFS诱发的海马突触LTP效应,其作用强于未电针组,部分参数和时段有统计学意义(P<0.05),且维持时间长于后者;东莨菪碱i.p可显著抑制HFS诱发的海马突触LTP(P<0.01),电针能显著对抗这一抑制作用(P<0.01;P<0.05)。结论 电针对HFS引起的海马突触LTP有一定的易化作用,并对东莨菪碱引起的学习记忆障碍有显著的对抗作用。  相似文献   
104.
It is documented that alkaline phosphatase (AP) plays an important role in bone mineralization. Considering that TN-AP is expressed in periodontal ligament fibroblasts, renal epithelial cells, and vascular endothelial cells, and that TN-AP is both a calcium-/phosphate-binding protein and a phosphohydrolytic enzyme, we hypothesize that membrane-bound AP also plays an important role in the initiation of physiological and pathological mineralizations in tissues other than bone and cartilage. To test this hypothesis, nonosteoblast cell lines, including a fibroblast line, a renal epithelial line, and a capillary endothelial line, were stably transfected to express high levels of rat bone AP on their cell surfaces. These rat bone AP-expressing cells were then cultured on filter membranes in the presence or absence of β-glycerol phosphate. von Kossa staining for calcium phosphate and transmission electron microscopy with electron diffraction analysis for minerals were employed to investigate the effect of membrane AP on extracellular calcium phosphate mineralization. Our results indicated that AP expression on these nonosteoblast-like cell surfaces have induced extracellular hydroxyapatite (HAP) mineralization. Our findings support the concept that membrane-bound AP contributes to extracellular apatitic mineralization by mechanisms that do not necessarily involve its hydrolase activity. They also suggest that AP might be important for the initiation of pathological mineralization in nonosteogenic tissues. Received: 11 January 1996 / Accepted: 31 October 1996  相似文献   
105.
目的:探讨和鉴别心电图短P-R间期的产生原因,为临床诊断、治疗提供依据。方法:检测115例受检者的常规导联心电图(RLECG)、头胸导联心电图(HCECG)、食管导联心电图(ELECG),对其中55例临床可疑心律失常和RLECG示短P-R间期者行食管心房调搏电生理检查。结果:①P波出现率和振幅均值比较ELECG>HCECG>RLECG(P<0.01),出现率分别为100%、95%、91%。②HCECGP-R段均值(P<0.01)及变异系数<RLECG。③RLECG波幅低、图形多变是产生心电图短P-R间期的主要原因。结论:作为无创伤性检查方法,HCECG和ELECG可以对短P-R间期者进行初步筛选,而经食管心房调搏能检测ECG短P-R间期的电生理特性,对鉴别诊断有肯定价值。  相似文献   
106.
The metabolism of 8-methyl-8-azabicyclo- 3,2,1]octan-3-yl 3,5-dichlorobenzoate (MDL 72,222) was studied in the dog and monkey. Four urinary metabolites were detected by HPLC, HPLC/MS, and GC/MS, and were identified by comparison to authentic standards. The major metabolite in the dog, approximately 41% of the administered dose excreted between 0 and 120 hr, was the MDL 72,222-N-oxide. On the other hand, the major metabolite in the monkey was the glycine conjugate of 3,5-dichlorobenzoic acid (greater than 56% of the dose). Seven percent of the dose in the monkey urine was free 3,5-dichlorobenzoic acid. N-Desmethyl MDL 72,222 was present at 2.5 and 1% in the dog and monkey, respectively. Very little (less than 1%) of the parent compound was found in urine. The major pathways of metabolism of MDL 72,222 are N-oxidation, N-demethylation, ester hydrolysis, and amino acid conjugation.  相似文献   
107.
蝮蛇抗栓酶对骨内高压降压作用实验研究   总被引:12,自引:0,他引:12  
本实验随机将家兔一侧后肢于膝关节伸直位夹板外固定5周,制成固定侧胫骨上端骨内高压模型。对其全身和局部血液流变学指标进行测定,发现全血粘度,血浆粘度增大,血沉增快,血浆纤维蛋白原含量明显增高。对上述模型应用蝮蛇抗栓酶(svate)连续治疗21天,骨内压降低,血液流变学各项指标亦降低。本实验结果显示,蝮蛇抗栓酶通过改善骨内高压状态下的异常血液流变学状态可使骨内高压降低,从而认为血液流变学疗法可能成为临床治疗骨内高压症的一种新手段,而蝮蛇抗栓酶可能为其中高效药物之一。  相似文献   
108.
目的:观察吸入一氧化氮(NO)对心瓣膜置换术后肺动脉高压患者血流动力学的影响。方法:选择9例心瓣膜置换术后伴肺动脉高压的病人,吸入NO0.003%,观察三个时象点:吸入NO前;开始吸入NO后15分钟;停止吸入NO后15分钟。结果:吸入NO能显著降低肺动脉压和肺循环阻力指数(P<0.01),停止吸入NO15分钟后,肺动脉压和肺循环阻力指数恢复到原有水平。在整个观察过程中,心率、平均动脉压、中心静脉压、肺动脉楔压、体循环阻力指数和心脏指数均无显著变化(P>0.05)。结论:吸入NO具有选择性肺血管扩张作用,是治疗心瓣膜置换术后肺动脉高压的较理想药物。  相似文献   
109.
Spinal cord injury: prognosis for ambulation based on quadriceps recovery.   总被引:1,自引:0,他引:1  
The purpose of this study was to determine if early recovery of quadricep muscle strength post spinal cord injury (SCI) is a useful predictor of future ambulation. Seventeen C4-T10 motor incomplete (Frankel C) spinal cord injured patients admitted to our center between March 1988 and April 1990 were examined within 72 hours to one week post injury. All patients had initial quadricep strengths < or = 2/5 in both legs. Strength in the strongest quadricep was followed prospectively at intervals from admission to one year post injury. Recovery time to a > 3/5 quadricep was established for each patient. Patients were categorized into 2 groups: FA (n = 11) were those patients who achieved functional ambulation and NA (n = 6) were those subjects who were nonambulators. Functional ambulators were defined as those patients who were able to walk in the household and/or the community while non ambulators were those who either did not ambulate or did so only for exercise. All patients (n = 9) who achieved a > 3/5 quadricep by 2 months post SCI became functional ambulators whereas in the group of 8 patients who did not achieve a > 3/5 by 2 months, only 2 became functional ambulators. This result was found to be significant using a point-by-serial correlation with p < 0.05. In conclusion, motor incomplete spinal cord injured patients who recovered to a > 3/5 quadricep strength by 2 months post injury had an excellent prognosis for subsequent ambulation by 6 months post injury.  相似文献   
110.
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