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81.
We found that the total watery extracts obtained from roots of various plants such as Symphytum officinale, Phytolacca americana etc, precipitate human glycoproteins, agglutinate sheep red blood cells (SRBC) and stimulate lymphocyte adherence to nylon fibers. Five out of seven extracts precipitated human gammaglobulins and one of seven obviously agglutinate SRBC. If these cells were pretreated with rabbit antibodies against SRBC, all extracts agglutinated the cells at various degrees of intensity, the most active being Phytolacca americana. The adherence of mouse but not human lymphocytes to nylon fibers was stimulated by extracts of Symphytum officinale and Phytolacca americana. This process was neither stimulated nor inhibited by Mannose (Man), Galactose (Gal), Glucose (Glc), N-acethyl Galactose (GalNAc) and N-acethyl Glucose (Glc-NAc). These biological effects of the plant extracts could be the expression of a lectin-like ability to bind various sugars other than those mentioned. The results suggest the possibility of using different extracts as means to point out the presence in serum or at the cellular level of some carbohydrates influencing the cellular adhesion, phenomenon which plays an important role in the functions of hematopoietic cells. 相似文献
82.
SR Hall 《Canadian Metallurgical Quarterly》1996,21(3):225-229
An asymmetric triazine derivative, HOE 092 V,2-[3,5-alpha-dichloro-4-(4-methyl-sulfonylphenoxy)-phenyl]- 1-methyl-hexahydro-1,2,4-triazine-3,5-dion, was tested in vivo against Glugea anomala parasitizing the connective tissue of sticklebacks (Gasterosteus aculeatus). Naturally infected sticklebacks were incubated in 10-1 plastic aquaria in water containing 0, 2.5, 5, and 10 micrograms HOE 092 V/ml for 2, 3, and 4 h at 22 degrees C. As seen at the ultrastructural level, the drug caused severe damage to all developmental stages of G. anomala except the mature spores. Starting with a dose of 2.5 micrograms/ml, the drug caused significant damage on uni- and multinucleate meronts, sporogonial plasmodia, and sporoblasts. The damage mainly consisted in a decrease in the number of ribosomes, an enlargement of the smooth endoplasmic reticulum and a vacuolization of the cytoplasma. When treatment was done with 5 micrograms for 2 h, multinucleate meronts and sporogonial plasmodia were no longer detectable, and the sporoblasts and the prespore stages except the mature spores had shrunk. After incubation of the infected fish with 10 micrograms HOE 092 V/ml and 4 h exposure, uninucleate meronts were no longer detectable by means of transmission electron microscopy. In the sporoblast mother cells, vacuolization of the cytoplasma and lysis of the nuclei occurred. However, mature spores were not affected. It seems likely that HOE 092 V can be successfully applied in medicinal baths against Microsporidia in fish. The infected fish should be incubated in separate, aerated containers. 相似文献
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84.
GV Naccarelli DL Wolbrette JT Dell'Orfano HM Patel JC Luck 《Canadian Metallurgical Quarterly》1998,9(8):864-891
Multiple trials using antiarrhythmic drugs, pharmacologic therapy, and implantable cardioverter defibrillators have been performed in an attempt to improve survival in patients: (1) postmyocardial infarction; (2) with congestive heart failure, with and without nonsustained ventricular tachycardia; and (3) with sustained ventricular tachycardia and those who have survived an out-of-hospital cardiac arrest. This article reviews some of the key findings and limitations of completed and ongoing trials. We also make recommendations for the current treatment of such patients based on the results of these trials. 相似文献
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87.
LA Parada G Bardi M Hallén I H?gerstrand KG Tranberg F Mitelman B Johansson 《Canadian Metallurgical Quarterly》1997,21(11):1381-1386
Hepatoblastomas usually occur in children < 3 years of age, and only occasional adult cases have been described. To date, 20 cytogenetically abnormal childhood hepatoblastomas have been reported. Karyotypic investigations have shown that most hepatoblastomas are diploid or hyperdiploid, often displaying trisomies for chromosomes 2 and 20. We have cytogenetically investigated an adult hepatoblastoma for which no previous karyotypic data exist. A hypertriploid stemline with multiple numerical and structural chromosomal aberrations, including +2 and +20, was found. In addition, the tumor displayed extensive clonal evolution with 11 subclones. Although the tumor thus displayed some chromosomal abnormalities commonly observed in childhood tumors, providing further support for the importance of these abnormalities in the development of hepatoblastoma, the level of genomic complexity seen in the present case has never been described in childhood hepatoblastomas and may suggest a different etiology or pathogenesis. 相似文献
88.
RD Lane DM Allan CA Bennett-Clarke DL Howell RW Rhoades 《Canadian Metallurgical Quarterly》1997,14(2):277-286
Immunocytochemistry and retrograde labeling were used to define the thalamic projections of calbindin- and parvalbumin-containing cells in superficial layers of the rat's superior colliculus (SC). Quantitative analysis revealed that 90.8 +/- 2.2% (mean +/- standard deviation) of the calbindin-immunoreactive neurons in the stratum griseum superficiale (SGS) projected to the dorsal lateral geniculate nucleus (LGNd) and that 91.3 +/- 4.3% of calbindin-immunoreactive neurons in the stratum opticum (SO) projected to the lateral posterior nucleus (LP). In contrast, only 17.3 +/- 2.5% of parvalbumin-immunoreactive neurons in the SGS were found to project to the LGNd and 16.5 +/- 3.1% of the parvalbumin-immunoreactive SO cells were retrogradely labeled after LP injections. Few of the parvalbumin-immunoreactive neurons in either the SGS (7.2 +/- 2.5%) or the SO (9.2 +/- 2.5%) were GABA positive. The retrograde-labeling results suggest that parvalbumin-immunoreactive neurons in the rat's SO and SGS may either be primarily interneurons or have descending projections, while calbindin-containing cells are primarily thalamic projection neurons. These results are consistent with data from other rodents, but almost exactly the opposite of data that have been reported for the cat for these same populations of SC projection neurons. Such interspecies differences raise questions regarding the functional importance of expressing one calcium-binding protein versus another in a specific neuronal population. 相似文献
89.
We studied the postnatal development of the release of acetylcholine (ACh) and of presynaptic, release-inhibiting muscarinic autoreceptors in the rat hippocampus. To this end, hippocampal slices (350 microns thick) from rats of various postnatal ages (postnatal day 3 [P3] to P16) were preincubated with [3H]choline and stimulated twice (S1, S2: 360 pulses, 2 ms, 3 Hz, 60 mA) during superfusion with physiological buffer containing hemicholinium-3 (10 microM). In parallel, the activities of hemicholinium-sensitive high-affinity choline uptake (HACU, in synaptosomes) and of choline acetyltransferase (ChAT, in crude homogenates) were determined as markers for the cholinergic ingrowth. In hippocampal slices preincubated with [3H]choline, the electrically evoked overflow of 3H at S1 increased from 0.11 (P3) to 0.81% of tissue 3H (P16), the latter value being still much lower than that of hippocampal slices from adult rats (2.89% of tissue 3H). Already at P3 the evoked overflow of 3H was Ca(2+)-dependent and sensitive to tetrodotoxin, indicating an action potential-evoked exocytotic mechanism of ACh release. The muscarinic agonist oxotremorine (1 microM) significantly inhibited the evoked ACh release in hippocampal slices with increasing effectivity from P4 to P16; no significant effect was detectable at P3. The ACh esterase inhibitor physostigmine and the muscarinic antagonist atropine (1 microM, each) exhibited significant inhibitory and facilitatory effects, respectively, only at P15-16. The specific activities of both hippocampal HACU (pmoles/mg protein/min) and ChAT (nmoles/mg protein/min) continuously increased from P3 to P16. It is concluded (1) that cholinergic nerve terminals arriving at the hippocampal formation during postnatal ingrowth are already endowed with the apparatus for action potential-induced, Ca(2+)-sensitive (exocytotic) ACh release; (2) that, in contrast, the expression of presynaptic muscarinic autoreceptors on these cholinergic axon terminals is delayed; and (3) that autoinhibition due to endogenous ACh develops even later, probably when the density of presynaptic terminals in the hippocampus and hence, the concentration of released ACh has reached a suprathreshold value. 相似文献
90.
A 66-year-old woman was admitted because of postmenopausal vaginal bleeding. Diagnostic workup revealed a poorly differentiated endometrial adenocarcinoma. A total abdominal hysterectomy and bilateral salpingo-oophorectomy was carried out (FIGO stage Ia, G3). One and a half years later she developed a solitary humeral metastasis which was treated by local radiotherapy and progesterone acetate. Because osseous metastases in endometrial adenocarcinoma are rare, the literature is reviewed. In analogy to the treatment of pulmonary metastases the option of disarticulation of the patient's arm is discussed. 相似文献