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91.
康继超  魏树礼 《药学学报》1997,32(7):536-541
为制备能用于清除骨髓中癌细胞的磁性微球,首先合成了单分散、大粒径的多孔聚苯乙烯交联微球,借助微球多孔结构对其进行磁化。探讨了影响磁化效果的主要因素。为使其与单抗连接紧密,在微球表面聚合了一层聚丙烯醛膜,使其表面带上易与单抗反应的醛基。同时测定了所制微球的磁响应性。X-射线衍射证明磁性物质为γ-Fe2O3。  相似文献   
92.
In a prospective hospital based study, during the period from Jan 95 to Dec 96, 3100 consecutively delivered live newborns were studied for the incidence of low birth weight neonates and to evaluate the associated risk factors. One thousand fourteen newborns were classified as low birth weight babies. The incidence expressed per 1000 live births was 327 (32.7%). Of these, 815 (80.4%) were small for gestational age neonates and 199 (19.6%) were preterm neonates. Five hundred seventy small for gestational age neonates (70%) were weighing between 2001 to 2500 gms. Mothers belonging to the age group of 19-25 years delivered the maximum number of low birth weight babies (618/1014) and of these 82.8% were small for gestational age neonates. There were 48 neonates with low birth weight born to mothers below the age of 18 years. Primiparous mothers were found to contribute higher number of low birth weight neonates (414/1014). Spacing as a factor did not show any major difference. Two hundred sixty two low birth weight neonates were born to mothers with significant obstetrical problems such as pregnancy induced hypertension, bad obstetrical history and premature rupture of membranes. The incidence of 32.7% of low birth weight babies is high enough to ring alarm bells.  相似文献   
93.
The present study has been carried out to study the hostility pattern of surgeons and compare it with other specialities. 100 teachers working in different specialities in Post Graduate Institute of Medical Sciences (PGIMS) Rohtak (Surgery and allied specialties 21, Medical and allied specialities 14, Non-clinical specialities 30) were given Hostility and Direction of Hostility Questionnaire (HDHQ) along with questions regarding their choice of career and Job satisfaction. Hostility pattern did not differ statistically among these groups. Surgeons showed strong aptitude for the field and were contended with their choice of speciality but their Job satisfaction was low. Possible explanations and implications of the study are discussed.Key Words: Hostility, Job satisfaction, Surgeons  相似文献   
94.
Hendrix  SL  Cochrane  BB  Nygaard  IE  沈平虎 《英国医学杂志》2006,9(1):48-49
问题:在绝经后健康妇女中,激素治疗(hormone therapy,HT)对尿失禁(urinary incontinence,UI)的效果如何?  相似文献   
95.
96.
Catalfamo  JL; Raymond  SL; White  JG; Dodds  WJ 《Blood》1986,67(6):1568-1577
A unique, intrinsic, hereditary canine platelet disorder attributable to abnormal fibrinogen receptor availability is described. Thrombopathic platelets from 13 severely affected basset hounds failed to aggregate in response to all agonists tested except thrombin. Normal platelet interaction with the various stimuli was inferred on the basis of their ability to elicit unimpaired shape change in thrombopathic platelets. No quantitative differences in major platelet membrane glycoproteins, intraplatelet fibrinogen, adenine nucleotides, or serotonin uptake were detected. Dense granule secretion was impaired. The ultrastructural appearance of thrombopathic platelets was normal. Fibrinogen-platelet interaction was evaluated by reacting platelet-rich plasma (PRP) with fibrinogen coupled to polymeric acrylonitrile beads and scoring the extent of stimulus-induced agglutination. The aggregatory responses of normal and thrombopathic platelets were closely correlated with fibrinogen receptor availability. In contrast to human platelets, epinephrine-stimulated canine platelets did not interact with immobilized fibrinogen, and arachidonate generally induced only weak agglutination. Thrombopathic platelets agglutinated fibrinogen beads at reduced rates when stimulated with physiologic doses of thrombin and high-dose calcium ionophore, A23187. Our data suggest that thrombin-mediated induction of canine platelet fibrinogen receptors may proceed by pathway(s) alternate to those shared by other platelet agonists, and/or that secreted granule constituents may act synergistically with thrombin to overcome inhibition of signal-response- coupled reactions mediating the interaction of fibrinogen with its receptor. This congenital platelet defect provides further evidence, in a species other than human, for the pivotal role of fibrinogen receptor induction in platelet aggregation.  相似文献   
97.
Schrier  SL; Junga  I; Ma  L 《Blood》1986,68(5):1008-1014
When amphipathic cationic drugs are added to intact human RBCs, the RBCs first undergo a stomatocytic shape change and then, if relatively large amounts of drug are added and if the metabolic state of the RBC is appropriate, endocytic vacuoles form. Vanadate has a structural similarity to the transition state of phosphate, which presumably accounts for its ability to inhibit phosphohydrolases, although other actions of vanadate have been described. Vanadate inhibited three forms of drug-induced endocytosis in intact RBCs despite the fact that the three drugs chosen (primaquine, chlorpromazine, and vinblastine) are known to have differing requirements for RBC ATP. Vanadate also inhibited the stomatocytic shape change produced by primaquine, chlorpromazine, and vinblastine, but not the stomatocytosis produced by low pH. Vanadate had no effect on RBC echinocytosis produced by lysophosphatidylcholine. In studying endocytosis in hypotonic, leaky, "white" ghosts, we discovered that vanadate inhibited only the endocytosis produced by Mg-ATP and not the endocytosis produced by manipulations that directly attack the cytoskeletal proteins. These findings suggest that ATP hydrolysis has a role in some forms of amphipathic cation-induced stomatocytosis and endocytosis in intact RBCs. In addition, studies in ghosts support the idea that Mg-ATP does indeed produce "energized" endocytosis dependent on utilization or hydrolysis of ATP.  相似文献   
98.
叶表面角质层对草珊瑚生药鉴定的意义   总被引:4,自引:0,他引:4  
本文用扫描电镜对草珊瑚Sarcandra glabra(Thunb.)Nakai叶表角质层进行了研究,发现不同产地和同株不同发育程度草珊瑚叶表角质层雕纹型式均有一些差异。  相似文献   
99.
100.
安宫牛黄丸中小檗碱的HPLC法测定   总被引:4,自引:0,他引:4  
本文报道用HPLC法测定黄连及含黄连中成药安宫牛黄丸中小檗碱型生物碱。实验结果表明选用硅胶柱为固定相,以醋酸乙酯—甲酸—乙醇(15:3:2)为流动相,能使样品中四种小檗碱型的生物碱获得最佳分离。用此法测得不同厂家生产的安宫牛黄丸中盐酸小檗碱的含量为0.331~0.456%,平均回收率为97.23%,变异系数为1.2%。  相似文献   
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