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91.
目的 探讨使用猪尾造影导管与单一化疗药盒连接实现肝脏肿瘤多重化疗的可行性及初步疗效。资料与方法 对30例晚期肝脏恶性肿瘤患者采用经股动脉穿刺、腹腔动脉内植入猪尾导管与皮下埋置药盒并序贯化疗,统计手术成功率、并发症及临床疗效。结果 30例手术全部成功,发生切口延迟愈合1例。术后随访28例,经影像学复查对比,病变缩小7例,稳定12例,进展9例。随访期间12例患者死亡,术后生存期42d-10个月,中位生存期6个月。另外16例患者至今存活,已达术后2-16个月。结论 采用猪尾造影导管置于腹腔动脉并与化疗药盒相连接,能够对晚期肝脏恶性肿瘤实现多重化疗,技术上简单可行,并发症少,初步疗效令人满意。  相似文献   
92.
The effect of electrical and chemical (l-glutamate) stimulation of the raphe obscurus on phrenic nerve activity was examined in the cat. Phrenic nerve activity was recorded from a C5 nerve root in anesthetized, paralyzed and artificially ventilated cats. Neural discharge was quantitated by integrating the phrenic nerve activity. The respiratory frequency was determined from the integrated nerve signal. Focal electrical stimulation (18–144 μA; 5–40 Hz; 100 μs pulse duration) resulted in significant (P < 0.05) increases in both integrated phrenic nerve (IPN) amplitude and respiratory frequency. These changes were dependent upon current intensity and frequency of stimulation. The largest increases in IPN amplitude and respiratory frequency were47 ± 17%and146 ± 8%, respectively. To insure that the changes in integrated phrenic nerve activity (IPNA) were the result of stimulation of cell bodies and not axons of passage,l-glutamate (100, 200 nmol) was microinjected (100 nl) into the raphe obscurus. Significant (P < 0.05) dose-related changes occurred in integrated phrenic nerve amplitude with an increase of44 ± 13% at 100 nmol and80 ± 13% at 200 nmoll-glutamate. No significant increase in respiratory frequency was observed withl-glutamate microinjection. The results suggest that the raphe obscurus may be involved in respiratory control.  相似文献   
93.
FOREWORDPeritonealdialysisrepresentssoluteandfluidexchangemainlybetweenperitonealcapillarybloodanddialysissolutionintheperitonealcavity'CombinedwithhemodialySisandrenaltransplantation,peritonealdialysisisusedmainlyforthetreatmentofrenalfailure,particularlyforchronicfailure'In1976,Prof'Popovichdevelopedcontinuousambulatoryperitonealdialysis(CAPD)basingontheconceptofcontinuousequilibrationdialysis('1'Fromthenon,peritonealdialysisfounditsclinicaluse'Continuouscyclicperitonealdialysis(CCPD…  相似文献   
94.
The distribution of serotoninergic fibers in the guinea pig cochlear nucleus was studied with serotonin immunohistochemistry. In addition, the origin of the serotoninergic fibers was determined by combining the retrograde transport of wheat germ agglutinin-apohorseradish peroxidase (gold conjugated) with serotonin immunohistochemistry. Immunoreactivity was present in varicose and nonvaricose fibers that were unevenly distributed throughout the cochlear nucleus. The fibers were most prominent in the superficial layers of the dorsal cochlear nucleus and the anterior spherical cell area of the anteroventral cochlear nucleus. Although less prominent, serotonin-positive fibers were also present in the remaining part of the anteroventral cochlear nucleus and the posteroventral cochlear nucleus. A few positive fibers were present in the auditory nerve root and the dorsal and intermediate acoustic stiae. Double-labeled cells were found throughout the rostral- caudal extent of the serotoninergic system from the caudal linear nucleus to the nucleus raphe pallidus. However, most were confined to the dorsal (52%) and median (18%) raphe nuclei. Some serotoninergic cell groups contained retrogradely labeled cells that were not serotonin immunoreactive, indicating nonauditory afferents to cochlear nucleus containing other neurotransmitter substances. Serotonin may tonically modulate auditory processing within the cochlear nucleus as well as influence certain ascending auditory pathways. Most of the serotonin in the cochlear nucleus comes from superior raphe nuclei that also project to basal ganglia motor systems and limbic strctures. Therefore, the effect of serotonin on the cochlear nucleus may be related to level of arousal or behavioral state. © 1995 Willy-Liss, Inc.  相似文献   
95.
Reproduction stops among the majority of prairie voles (Microtus ochrogaster) during the winter. Short day lengths suppress male reproductive function dramatically in the laboratory, but photoperiod exerts only subtle effects on female reproductive function. Thus, the regulation of seasonal breeding in this species remains partially unspecified. In contrast to commonly studied rodents, female prairie voles do not undergo spontaneous estrous cycles; rather, they are induced into estrus by exposure to chemosignals expressed in conspecific male urine. In the present study, the hypothesis was tested that seasonal breeding among female prairie voles in the field reflects photoperiod-mediated changes in the responsiveness of the chemosensory system to male urine. Responsiveness was assessed by localizing the product of the c-fos immediate early gene with an immunocytochemical procedure. Female prairie voles were maintained in either long (LD 16:8) or short (LD 8:16) photoperiods from birth until adulthood, and exposed to either male urine or skim milk. Immunocytochemistry forfos protein revealed an increased number of immunoreactive cells within the accessory olfactory system of female prairie voles, including the accessory olfactory bulbs, granule cell layer, as well as the medial and cortical divisions of the amygdala 1 h after exposure to a single drop of urine as compared to individuals exposed to skim milk. The number of immunoreactivefos cells induced in females by conspecific male urine was also affected by photoperiod; short day females displayed fewer immunoreactivefos neurons in the accessory olfactory system as compared to long-day animal. Taken together, these results indicate that similar mechanisms underlie the responses of different rodent species to the chemosignals of conspecifics and that the pattern offos expression observed in the present study has functional significance for the regulation of reproduction in prairie voles.  相似文献   
96.
We studied the effects of cardiac rehabilitation on the sympathovagalcontrol of heart rate variability in 30 patients after a first,uncomplicated myocardial infarction. Twenty-two patients completed8 weeks of endurance training (trained), while eight decidednot to engage in the rehabilitation programme for logisticalreasons, and were taken as untrained controls. Age, site ofinfarction, ejection fraction, ventricular diameter and stresstest duration were similar in the two groups at baseline. Heartrate variability was evaluated 4 weeks after infarction beforestarting rehabilitation, and repeated 8 weeks and one year laterin both trained and untrained patients. Measures of heart ratevariability, obtained from both time- and frequency- domainanalysis of a 15 min ECG recording in resting conditions, wereas follows: mean RR interval and its standard deviation (RRSD),the mean square successive differences (MSSD), the percent ofRR intervals differing >50 ms from the preceding RR (pNTN50),the low and high frequency components of the autoregressivepower spectrum of the RR intervals and their ratio (LF/HF).At baseline, heart rate variability was similar in trained anduntrained patients. In the short term (8 weeks after infarction),training increased RRSD by 25% (P<0·01), MSSD by 69%(P<0·01), pNN50 by 120% (P<0·01), and reducedLF/HF ratio by 30% (P<0·01). The effects persistedafter one year in trained patients. In untrained patients, theautonomic control of heart rate variability did not change 8weeks after myocardial infarction and was only slightly modifiedby time. Thus, exercise training, performed for 8 weeks aftera myocardial infarction, modifies the sympathovagal controlof heart rate variability toward a persistent increase in parasympathetictone, known to be associated with a better prognosis. This maypartly account for the favourable outcome of patients who undergorehabilitation.  相似文献   
97.
The inhibition of conjugative transfer of derepressed plasmids was appreciably increased in polyplasmid complexes ofEscherichia coli K-12 cells containing two repressed conjugative plasmids with the finV system of genetic transfer regulation, in comparison with the individual effects of each of the two plasmids. Combination of two plasmids with the finU system or of plasmids with the finU and finV systems did not result in such an increase of inhibitory activity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 12, pp. 619–622, December, 1995 Presented by T. T. Berezov, Member of the Russian Academy of Medical Sciences  相似文献   
98.
Summary A large series of central and peripheral nervous system tumors was studied for the presence of glial fibrillary acidic protein (GFAP) and -enolase (neuron-specific enolase, NSE), using specific monoclonal antibodies (mAbs). Occurrence in and specificity of GFAP to glial and mixed tumors was confirmed and depended on the malignancy grade and features such as meningeal invasion. Using a well-characterized mAb, -enolase was demonstrated in neuronal, as well as in a whole range of non-neuronal tumors. This lack of specificity of -enolase prohibits its use as an exclusive neuronal marker. Nevertheless quantization or comparison with other types of enolases could still prove to be useful in well-defined situations. The advantages inherent to mAbs and a highly sensitive detection system turn GFAP stainings into a specific and readily reproducible technique.Supported in part by FGWO (grant no. 3.0019.86) and by the Geconcerteerde Actie (grant no. 84/89-68, Brain specific proteins)  相似文献   
99.
Simulation of space adaptation syndrome on earth   总被引:2,自引:0,他引:2  
Summary The three Spacelab D-1 Scientist Astronauts were exposed to a 11/2 h 3 g centrifuge run in the supine position, resulting in a linear 3 g acceleration in the x-direction. They used their space experience to evaluate their readapting to normal gravity and compared their observations with Space Adaptation Syndrome. After the centrifuge runs, the vestibular visual system appeared to be modified in a very specific and reproducible manner. Readapting to the normal 1 g environment took at least 6 h. During this period there was a striking similarity to the astronaut's experience during adaptation to weightlessness in space. A series of vestibular tests were then performed, confirming these subjective findings.  相似文献   
100.
Summary The effect of the complement-derived polypeptide C3adesArg as a mediator of inflammation in the central nervous system was examined. Twenty-five anesthetized cats received 4 mg of this polypeptide by intraventricular injection, 20 cats who served as controls received saline. Cerebrospinal fluid (CSF) was sampled 3 h after intraventricular injection and the brains were removed. For assessment of the permeability of the blood-brain barrier the CSF penetration of four antibiotics, which were given intravenously, was measured. Five control animals were employed for each antibiotic (tobramycin, ampicillin, imipenem, fosfomycin), whereas six C3adesArg-treated animals were used for each antibiotic and seven for tobramycin. Besides CSF levels of glucose, the prostanoids 6-keto-prostaglandin F1, thromboxane B2 and prostaglandin E2 were measured. The morphological examinations in the CSF sediments and histological brain sections in the C3adesArg-treated animals disclosed a distinct inflammation with leptomeningeal and perivascular infiltration of polymorphonuclear granulocytes compared to normal findings in the controls. The CSF/serum ratios of all of the antibiotics were markedly elevated compared to controls, indicating a blood-brain barrier disruption. The levels of all prostanoids were significantly higher in the treatment group than in the control group, whereas the glucose levels were lower. These findings are in accordance with a granulocytic meningitis as seen in some infections at the acute stage. It is concluded that C3adesArg acts as a mediator of inflammation in the central nervous system.  相似文献   
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