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81.
The microcirculatory architecture of normal tissue, transitional mucosa and adenocarcinoma of the human colon was investigated with microvascular corrosion casting (MVCC) combined with scanning electron microscopy (SEM). The study showed that the capillaries within the normal mucosa were arranged in a regular hexagonal pattern around the mucosal glands and that the microvessels of transitional mucosa mostly had lost the typical hexagonal pattern and become slightly wider in diameter. The microvessels in the tumor periphery were increased in number and disorganized, and presented large variation in morphology with claw-like formations, widened sinuses, diverticula and appendixoid patterns. Microvessels were lacking in the central areas of tumors. These morphological alterations may serve as additional indicators of tumor development.  相似文献   
82.
华蟾蜍毒素对离体豚鼠输精管的作用   总被引:3,自引:0,他引:3  
韩永晶  张力  崔荣芬 《药学学报》1992,27(4):252-255
华蟾蜍毒素(华蟾素)使离体豚鼠输精管产生剂量依赖性收缩反应,利血平化豚鼠输精管及冷藏输精管对华蟾素反应减弱。给酚妥拉明、维拉帕米后,输精管对华蟾素反应均受抑制,溴苄胺可使反应潜伏期缩短。结果提示华蟾素收缩输精管反应可能与其促进肾上腺素能神经末稍NA释放有关。  相似文献   
83.
Ninety cases of infertility and habitual abortion were analyzed by hysteroscopy between April 1983 and July 1990 in PUMC hospital. Abnormal changes of the uterine cavity were seen in 74.4%. The result of hysterosalpingography corresponded with that of hysteroscopy in 62.5%, and the result of B-ultrasound corresponded to that of hysteroscopy in 52.5%. The diagnosis of adhesion and polyps of the uterine cavity was made accurately by hysteroscopy, and both could be operated under hysteroscopy. After operative removal of the adhesion, an IUD should be put into the uterine cavity for 3 months. In 60 cases operations were performed during or after hysteroscopy. Of the 45 patients followed, 19 achieved pregnancy. Five patients achieved pregnancy after operative removal of the adhesion. It is concluded that hysteroscopy is more important than B-ultrasound and hysterosalpingography in the examination and treatment of infertility.  相似文献   
84.
J Zhuang  M Zhang  Z Zeng  F Xu  T Han  S Hu  Y Sun 《中国中药杂志》1992,17(8):496-9, inside backcover
The purpose of this study is to discuss the effects of the Chinese medicine six-flavor Rehmannia Decoction with additives on preventing deafness induced by gentamicin (GM) in guinea pig by means of testing the thresholds of Preyer's reflex (PR) cochlear microphonic potential (CM), action potential of the auditory nerve (N1) and scanning electron microscope of inner ear (SEM). The results showed that the medicine is effective in reducing the ototoxic effect of GM on inner ear.  相似文献   
85.
癌旁组织CD44vmRNA的表达对原发性肝癌术后复发的影响   总被引:4,自引:0,他引:4  
研究原发性肝癌癌旁组织CD44vmRNA表达的意义。应用RT-PCR检测原发性肝癌癌旁组织CD44vmRNA的表达并结合术后近2年的随访结果进行综合分析。癌旁组织CD44vmRNA表达高于癌组织者的肿瘤包膜缺如、门静脉癌栓和瘤周卫星结节等与转移相 关的病理指标高于癌旁组织CD44vmRNA表达低于癌组织的病例,前者复发率亦高于后者。结论:癌旁组织CD44vmRNA的表达肝癌侵袭潜能以及预测其复发等  相似文献   
86.
应用光化学诱导法建立免局灶性脑梗塞模型,为临床治疗人的脑梗塞疾病提供有效的实验研究手段。结果显示,模型制作成功率98%,梗塞灶面积为0.465±0.012 cm2,体积为0.268±0.009 cm3,梗塞灶呈典型的损伤、渗出和炎症反应病理过程。结果提示,光化学诱导法建立免局灶性脑梗塞模型方便、快速、稳定。  相似文献   
87.
开放手术观察腰椎间盘突出症溶核失败45例分析   总被引:2,自引:2,他引:0  
目的 通过开放手术观察分析椎间盘髓核化学溶解术治疗腰椎间盘突出症失败原因。方法 收集溶核失败的腰椎间盘突出症45例行开放手术治疗。结果 术中见45例硬膜外脂肪完全消失,43例髓核未见溶解,2例髓核溶解呈糊状但未被吸收,21例伴有侧隐窝狭窄,15例突出物与神经根粘连,20例黄韧带增厚,2例椎管骨性狭窄,14例突出物钙化。结论 腰椎间盘突出症病变间隙合并有侧隐窝狭窄、神经根粘连、椎管狭窄、突出物钙化等,不是溶核治疗的适应证。  相似文献   
88.
BACKGROUND: Craniocerebral injury always accompanies with singultus, while frequent singultus may cause increased intracranial pressure. Simultaneously, respiratory alkalosis and cerebral hypoxia induced by respiratory disorder may aggravate craniocerebral injury. OBJECTIVE: To observe the therapeutic effects of intranasal cavity drip infusion of aminazine and intramuscular injection on singultus following craniocerebral injury. DESIGN: Contrast observation. SETTING: Department of Neurosurgery, Xi'an Aerospace General Hospital. PARTICIPANTS: A total of 102 patients with singultus following craniocerebral injury were selected from the Department of Neurosurgery, Xi'an Aerospace General Hospital from June 2001 to June 2006. Patients with craniocerebral injury were diagnosed with CT examination and randomly divided into nasal cavity medication group (n =62) and intramuscular injection group (n =40). There were 44 males and 18 females in the nasal cavity medication group and their mean age was (33±4) years; while, there were 26 males and 14 females in the intramuscular injection group and their mean age was (29±4) years. All patients and their relatives provided the confirmed consent. METHODS: Patients in the nasal cavity medication group were slowly dripped aminazine solution into bilateral nasal cavity with the dosage of 12.5 mg (0.5 mL). Patients who had no obvious effect or had mild improvement received the treatment once every 6 hours. The treatment was stopped if symptoms were also observed after the fifth medication. In addition, patients in the intramuscular injection group received intramuscular injection of 50 mg aminazine. Patients who had no obvious effect or had mild improvement received the treatment once every 6 hours. The treatment was changed if symptoms were also observed after the fifth medication. MAIN OUTCOME MEASURES: Therapeutic effects of different medications in the two groups. RESULTS: All 102 patients were involved in the final analysis. Effective rate in the nasal cavity medication group was higher than that in the intramuscular injection group, and there was significant difference (χ2= 11.882, P < 0.01). At 6 hours after onset of singultus, effective rate in the nasal cavity medication group was higher than that in the intramuscular injection group, and there was significant difference (χ2 =8.188, P < 0.01). CONCLUSION: Therapeutic effects of intranasal cavity drip infusion of aminazine on singultus following craniocerebral injury are superior to those of intramuscular injection.  相似文献   
89.
Lipophilic diaminocyclohexane (DACH) platinum complexes have shown significant promise in preclinical studies. One of these compounds,cis-bis-neodecanoato-trans-R,R-1,2-diaminocyclohexaneplatinum(II) (NDDP), which contains two branched leaving groups of 10 carbons, showed a favorable toxicity profile in a liposomal formulation in early clinical trials. However, like many other DACH platinum compounds with branched leaving groups, it is unstable within the liposomes, thus preventing its widespread clinical evaluation. We studied the effect of the configuration of leaving groups on intraliposomal complex stability by studying a series of DACH platinum complexes containing linear alkyl carboxylato leaving groups of 5–18 carbons. The entrapment efficiency was greater than 90% for all liposomal preparations of the complexes and was independent of lipid composition and length of the leaving group. The drug leakage from the liposomes was minimal, but was directly related to the length of the leaving group. Intraliposomal stability was inversely related to the length of the leaving group and the content of DMPG (dimyristoyl phosphatidylglycerol) in the liposomes. The effect of length of leaving group on intraliposomal stability was minimal in compounds with leaving groups smaller than 10 carbons, but very pronounced in compounds with longer leaving groups. Stable liposomal formulations of selected compounds with leaving groups of 6 and 10 carbons had significant in vivo antitumor activity against both L1210/S and L1210/PDD leukemias. The results indicate (1) that compounds with linear leaving groups are much more stable within DMPG-containing liposomes than compounds with branched leaving groups and (2) that DMPG is required for in vivo antitumor activity. Stable and active liposomal formulations of selected compounds with linear leaving groups have been identified. These formulations are candidates for clinical development.Abbreviations DMPC dimyristoyl phosphatidylcholine - DMPG dimyristoyl phosphatidylglycerol - L-NDDP liposomalcis-bis-neodecanoato-trans-1,2-diaminocyclohexaneplatinum(II) The work reported in this paper was supported in part by NIH grants CA 41581, 45423, 50270, and 58342  相似文献   
90.
韩素莉  斋藤健 《卫生研究》1994,23(6):328-330
给大鼠经气管分别注入4、16、64mg石英粉尘生理盐水混悬液。在染尘后第7,15和30天解剖动物,测定血浆中Cu、Zn,Mn、Mo、Si、Rb和Sr等7种微量元素的含量。实验结果表明,随着染尘剂量的增加,血浆中铜的含量明显增高,呈正相关,相关系数为0.999。而血浆锌的含量随着染尘剂量的增加而明显的降低,呈负相关,相关系数为-0.998。血浆中Mo、Mn、Si、Rb和Sr含量与对照组比无明显差异。  相似文献   
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