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71.
A Sprague-Dawley rat model with DS sarcoma transplanted in the thigh was used to compare transcatheter locoregional i.a. and systemic i.v. administration of 5-fluorouracil (FU) at 12 dose-rate schedules: 25, 50 and 100 mg/kg; bolus, 1, 5 and 24 h infusions. In experiment A tumor (62/67 animals) as well as liver and kidney (56/67 animals) were excised 1 h after a single bolus or 1 h infusion or at the end of 5 and 24 h infusions. (19)F-NMR spectroscopy at 11.7 T was used to quantitate FU and its metabolites in ca. 1 g of tissue at 4 degrees C. In experiment B analogous FU treatments were repeated for 5 days (rats 80+11 controls). Tumor volumes vs time, various blood parameters and survival times were recorded, and a log growth rate parameter log GR, a response index RI, and a toxicity index TI were calculated. The i.a. vs i.v. ratios for tumor concentrations of FU and total anabolites (F-Nucl) were >1 for nearly all treatments and increased with infusion time at the higher doses. F-Nucl in tumor correlated linearly with total fluorine concentration (Tot. F range 30-1100 nmol/g) over all treatments (r=0.92, slope=0.45, p<0.0001). For non-bolus i.v. treatments [FU+F-Nucl] decreased linearly with decreasing FU dose rate (r(2)=0.74, zero intercept), while i.a. treatments showed non-linear behavior. For non-bolus treatments the mean log GR per treatment group showed a negative correlation (r=-0.87) with log[F-Nucl]. The most effective non-toxic treatments were 25 mg/kg over 5 or 24 h; the i.a. route was superior to i.v. on the basis of [FU+F-Nucl], RI, the reduction in log GR, and Kaplan-Meier survival statistics. For liver and kidney Tot. F (>83% FU catabolites) reached ca. 3-4 and 6-7 micromol/g, respectively, at the highest dose rates for either route; F-Nucl were detected only for Tot. F>500 nmol/g and increased exponentially as Tot. F increased (toxic treatments). The concentrations of the main catabolite (alpha-fluoro-beta-alanine, FBAL) in tumor did not correlate with Tot. F but rather with FBAL levels in kidney (r=0.90, all treatments), indicating that uptake of liver-derived FBAL from the circulation is the major source of FBAL in tumor. 相似文献
72.
Lida Bruni Barbara Angeletti Esterina Pascale Maria Cristina Tozzi Paola Giammaria Roberto Verna Ettore D'Ambrosio 《Clinical genetics》1996,50(2):89-92
Genotyping with flanking DNA markers was used to ascertain Treacher Collins Franceschetti syndrome (TCOF1) in a subject affected by tetralogy of Fallot and cryptorchidism. The proband's family consisted of a father and sister who were affected by the disease, and a healthy mother. Since cardiac malformation and cryptorchidism have been associated with the TCOF1 syndrome, the proband was suspected to be a carrier of the mutated gene. Microsatellite markers D5S527, SPARC and D5S519, which previously mapped the TCOF1 gene within a 2.1-cM interval on chromosome 5 (5q32–33.1), were used to follow the transmission of the TCOf 1 mutated locus. Flanking markers D5S519 and D5S527 were informative and enabled us to exclude inheritance of a TCOF1 mutation to the proband, while showing that cardiac malformation and cryptorchidism were unrelated in mis patient. 相似文献
73.
The acute effects of the deposition of papain in the lungs of 4-month-old rabbits have been investigated with an amount not sufficient to cause emphysematous changes. During the first 2 days of in vivo deposition when hemorrhaging and inflammation occur, the total amounts of collagen and elastin in the lung, into which the papain had been instilled, did not change but the concentrations of collagen and elastin decreased 20 and 25% respectively. The rates of synthesis of collagen and other proteins doubled. By 4 weeks, collagen and elastin concentrations returned to, or were slightly above, control levels. The histological appearance and mean linear intercepts of lung sections and the compliance curves of excised lungs of the treated animals were similar to controls by 2 weeks after papain administration. The rabbit lung thus appears able to repair mild injury due to proteolytic enzymes. 相似文献
74.
The presence of angiotensinogen, the precursor of angiotensin II (ANG II), in brain tissue and in cerebrospinal fluid (CSF) allows stimulation of endogenous brain ANG II by renin. Passive avoidance tests were performed in female Wistar rats. The animals received an electrical shock after entering a black box on the first experimental day. Avoidance was tested every 24 h for 5 consecutive days. Renin in doses of 0.01 and 0.1 units was injected once into the lateral brain ventricles 2 min before the first test. CSF ANG II increased from 40 to 4547 and 5152 fmol per ml (means), respectively. A dose-dependent disruption of avoidance learning was observed, the frequency to enter the black box increasing from 11% (control) to 29% and 46%, and the latency decreasing from 165 (control) to 143 and 116 sec, respectively. These effects were statistically significant (P less than 0.001) for more than 24 h and returned to control levels after 48 to 120 h. Administration of the converting-enzyme inhibitor SQ 14225 i.v.t. prior to renin injections abolished the renin effects. Injections of renin given 22 h after learning were without effect. 相似文献
75.
Susumu Yamada Roko Kubota Kazuo Kubota Kiichi Ishiwata Tatsuo Ido 《Neuroscience letters》1990,120(2):191-193
This is the first study of micro-autoradiography (micro-ARG) for [18F]2-fluoro-2-deoxy-
-glucose ([18F]FDG). The localization of [18F]FDG was demonstrated in dendrites of neuron and also in the myelinated axon in mouse normal brain in vivo. The nucleolus was relatively free of label. The counted silver grain numbers in autoradiogram were linearly correlated to the 18F radioactivities in the specimen. The micro-ARG using positron emitting 18F is a very time-saving technique with 4 hours exposure compared with the conventional method using 3H- or 14C-labeled tracers. 相似文献
76.
During three different motor tasks of finger, wrist and arm movements on either side, 80 pyramidal tract neuron (PTN) activities were recorded in the monkey motor cortex. They were divided into three groups; PTNs related to controlateral movement (contra-PTNs), those related to ipsilateral movementt lateral movement (bilaterai-PTNs) and those related to ipsilateral movement (ipsi-PTNs). The latency histogram of the antidromic activation was similar for contra-PTNs as well as ipsi- and bilateral-PTNs in the fast PTN group, but most of slow PTNs appeared among contra-PTNs. Intracortical microstimulation (ICMS) was delivered to correlate muscular contraction with PTN acticity. Most of slow PTNs were related to proximal muscular contraction and PTNs related to proximal muscles appeared more in ipsi- and bilateral-PTNs than in contra-PTNs. 相似文献
77.
中药猫人参,又名大籽猕猴桃,是著名抗癌药用植物,其野生资源已近枯竭。本文选用猫人参的茎段(至少带一个节)、叶片作为外植体,筛选出了适合猫人参从启动、快繁直至生根等各个阶段的最适培养基,在实验室建立了程序简单、重复性好的再生系统,实现了猫人参组培苗的快速繁殖。以茎段作为外植体效果较好,既容易消毒,同时又能很快诱导腋芽萌发;以叶片作为外植体,能成功诱导出愈伤组织,但此愈伤组织的分化能力极低。以茎段作为外植体获得的无菌培养物在不同发育阶段适宜的培养基组成:外植体启动培养基为MS+BA 5 μmol/L+NAA 1 μmol/L;最适增殖培养基为MS+BA2 μmol/L+GA 1.5 μmol/L+ZT 4μmol/L,35 d繁殖系数为9-10;最适生根培养基为1/2MS+IBA 2μmol/L,生根率达1 00%,培养35 d,平均苗高6.28cm,平均移栽成活率为91%。 相似文献
78.
Monoclonal antibody LICR -LON- M18 identifies the immunodominant oligosaccharide sequence of the I(Ma) blood-group antigen: Gal beta 1----4GlcNAc beta 1----6--. In primary breast cancers this structure is almost totally cryptic, due to "masking" by sialic acid, but can be revealed by digestion with the specific glycosidase neuraminidase. Following desialylation, light microscopic immunohistochemical examination has revealed the epitope identified by LICR -LON- M18 to be heterogeneously distributed throughout the population of breast carcinoma cells. These tumor cells express the antigen as both a cytoplasmic and a surface membrane determinant. In the normal human breast, this structure is expressed exclusively along the luminal plasma membranes of the duct and alveolar littoral epithelial cells. Desialylation of tissue sections of normal resting and lactating breast epithelium with neuraminidase virtually abolishes the heterogeneous intercellular distribution of the I(Ma) determinant. In desialylated nonneoplastic breast tissues, the expression of this antigen is observed within the cytoplasm of some myoepithelial cells, but not in the littoral epithelial cells. The expression of the I(Ma) antigen by neoplastic and normal breast epithelial cells has also been compared with that of the oligosaccharide sequence Gal beta 1----3GalNAc. This structure, recognized by peanut agglutinin, forms the dominant portion of the Thomsen-Friedenreich antigen. With respect to normal and lactating breast epithelial cells, both oligosaccharide structures are sialylated and appear to be similarly misprocessed by breast carcinomas. The masking of surface carbohydrate determinants and the faulty processing of structures usually expressed on the surface of non-neoplastic breast epithelial cells may be important phenomena in the pathobiology of breast carcinomas. 相似文献
79.
Polymorphic variants in the gene encoding factor VII (F7) affect the plasma levels of this coagulation protein and modify the clinical phenotype of FVII deficiency in some patients. In this study we report the in vitro functional analysis of a novel polymorphic variant located in the 3' untranslated region of F7: g.11293_11294insAA. To determine whether this variant regulates FVII expression, we initially compared an expression vector containing FVII cDNA with g.11293_11294insAA with the FVII wild-type (WT) construct. The kinetics of mRNA production showed that the insertion decreases the steady-state FVII mRNA levels. To assess whether the insertion influences the phenotype of FVII-deficient patients, we evaluated its effect on the expression of FVII in a patient with severe FVII deficiency (undetectable FVII activity and antigen) carrying two additional homozygous missense variations (p.Arg277Cys and p.Arg353Gln). The two substitutions alone reduced the expression of FVII activity and antigen in vitro, but with the insertion polymorphism in our expression vector the patient's phenotype of undetectable plasma FVII was recapitulated. The insertion polymorphism in the 3' untranslated region of F7 is another modifier of FVII expression that might explain the poor genotype-phenotype correlation in some FVII-deficient patients. 相似文献
80.
The morphology of Merkel cells in sinus hair follicles of the upper lip (vibrissae with a circular blood sinus), and in touch domes of the glabrous skin of the nose, was investigated in cats up to 12 weeks after resection of the infraorbital nerve. Even 12 weeks after denervation there was neither an ultrastructural alteration of Merkel cells nor a reduction of their number in sinus hair follicles. Also in touch domes the Merkel cells did not disappear. 相似文献