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991.
C.C.-W. YU P.A. HALL C.D.M. FLETCHER R.S. CAMPLEJOHN N.H. WASEEM D.P. LANE D.A. LEVISON 《Histopathology》1991,19(1):29-34
Forty-two cases of haemangiopericytoma were studied retrospectively using immunohistochemical staining with PC10, a monoclonal antibody to PCNA. The percentage of tumour cells with positive staining for PCNA was found to correlate well with histological grading. Clinical follow-up data were available in 25 adults and showed no known deaths in 11 cases with a low proportion (less than 14%) of positive cells. Out of 14 cases with a high number (greater than or equal to 14%) of positive cells, seven patients are known to have died, two had metastases, and in a further two there have been multiple recurrences of tumour. DNA flow cytometry was performed on 26 cases but this showed no correlation with PC10 staining or clinical outcome. Staining with PC10 may be of particular value in the identification of patients at greatest risk of rapid tumour metastasis and early death. 相似文献
992.
V. K. Bozhenko E. V. Khmelevskii A. M. Shishkin V. N. Vasil'ev A. G. Zakharov V. I. Kiselev 《Bulletin of experimental biology and medicine》1994,117(3):297-299
The dynamics of125I distribution is studied in rats with induced tumors of the prostate and mammary gland for intravenous administration of125I-3D-G. It is found that 80% of the activity is eliminated in the first 24 hours. A relatively high level of125I accumulation is found in necrotically altered regions of the tumor.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, № 3, pp. 294–295, March, 1994. 相似文献
993.
Hideto SAKAI Kiichiro JINDE Noboru SAOTOME Wei SUNG Mitsunori YAGAME Yasuo NOMOTO Masanobu MIYAZAKI Takashi HARADA 《Nephrology (Carlton, Vic.)》1997,3(1):91-94
Summary: In situ hybridization of mRNA for collagen IV, collagen VI, stromelysin (MMP-3) and TIMP1 was examined in renal biopsy specimens from patients with IgA nephropathy (IgAN) or diabetic nephropathy with various degrees of tissue damage. The majority of cells in the glomeruli expressed these mRNA almost simultaneously, but a few cells demonstrated positive expression for only one of these probes. There was a parallel relationship between the degree of tissue damage and that of mRNA expressions of these probes in patients with IgAN, while patients with diabetic nephropathy showed a reverse relationship between these two parameters. It is concluded that patients with mesangial proliferative glomerulonephritis expressed mRNA for collagen collagenase and its inhibitor in the glomeruli in parallel with the progress of tissue damage. In contrast, glomerular samples from patients with diabetic nephropathy showed that there was an inverse relationship between tissue damage and expression of mRNA. It is concluded that expression of collagen, collagenase and its inhibitor parallels the progression of glomerular changes in IgAN, but such parallel expression was not observed in patients with diabetic nephropathy. 相似文献
994.
Summary
The introduction of fast gradient systems allows a reliable visualization of the extracranial carotid vessels by the magnetic
resonance angiography (MRA) which meanwhile is implemented into clinical routine. By the mainly applied time-of-flight (TOF)
technique, vessels can be imaged without contrast agent (CA). Due to the application of ultra-fast gradient-echo-sequences,
the first-pass evaluation of an intravenous bolus-injection of Gadolinium in the carotids from the aortic arch up to the skull
base can be performed in less than 30 s. In this study, advantages and disadvantages of both techniques are discussed. For
a qualitatively optimal contrast enhanced MRA (CE-MRA) timing parameters like injection delay, flow rate and the adjustment
of sequence parameters have to be considered in relation to the fast venous return from the sinus to the jugular veins. First,
the optimal time point of the data acquisition have been determined at a model and with a computer simulation in reference
to the presence of CA in the arteries. As a result, 90 % of the contrast contribution is defined by 16 % of the symmetrically
acquired central k-space lines. A measuring protocol for clinical use was obtained by a gradual variation of spacial resolution,
measuring time and CA-injection parameters and was proved in normal volunteers and patients. An exact determination of the
bolus-arrival-time by means of a test-bolus injection was acquired. The best qualitative results were achieved by a double-dose
injection at 2 ml/s injection rate. The temporal reserves of ultra-fast sequences should be invested in the improvement of
the spatial resolution. To date, further investigations related to the problem of optimal CA-application may improve the potentials
of CE-MRA procedures.
相似文献
995.
Acetylcholinesterase Adaptation to Voluntary Wheel Running is Proportional to the Volume of Activity in Fast, but not Slow, Rat Hindlimb Muscles 总被引:4,自引:0,他引:4
Victor Gisiger Manon Bélisle Phillip F. Gardiner 《The European journal of neuroscience》1994,6(5):673-680
Chronic enhancement of neuromuscular activity by forced exercise training programmes results in selective adaptation of the G4 acetylcholinesterase (AChE) molecular form in hindlimb fast muscles of the rat, with only minor and non-selective AChE changes in the soleus. In order to shed further light on the physiological significance of this G4 adaptation to training, we turned to a voluntary exercise model. The impact of 5 days and 4 weeks of voluntary wheel cage running on AChE molecular forms was examined in four hindlimb fast muscles and the slow-twitch soleus from two rat strains. Inbred Fisher and Sprague– Dawley rats, placed in live-in wheel cages, exercised spontaneously for distances which progressively increased up to an average of ∼3 and 18 km/day, respectively, by the end of week 4. Fast muscles responded to this voluntary activity by massive G4 increases (up to 420%) with almost no changes in A12 , so that by week 4 the tetramer became the main AChE component of these muscles. The additional G4 was composed primarily of amphiphilic molecules, suggesting a membrane-bound state. The G4 content of fast muscles was highly correlated with the distance covered by the rats during the 5 days before they were killed ( r = 0.850-0.879, P < 0.001 in three muscles). The soleus muscle, in turn, responded to wheel cage activity by a marked selective reduction of its asymmetric forms—up to 45% for A12 . This A12 decline, already maximal by day 5 of wheel cage running, showed no relationship with the distance covered. The present results constitute strong new evidence suggesting that the role of AChE in neuromuscular transmission is not limited solely to the rapid inactivation of just-released acetylcholine. 相似文献
996.
A. Newman-Tancredi V. Audinot V. Jacques J. L. Peglion M. J. Millan 《Neuropharmacology》1995,34(12):1693-1696
The selective dopamine D3 receptor antagonist [3H](+)S 14297 ((+)-[7-(N,N-dipropylamino)-5,6,7,8-tetrahydro-naphtho(2,3b)dihydro,2,3-furane]), labelled to high specific activity (145 Ci/mmol), bound to cloned human dopamine D3 receptors but displayed negligible binding to cloned human D2 receptors. [3H](+)S 14297 exhibited rapid association and dissociation, high affinity saturable binding (Kd = 7.0 nM) and a competition binding profile highly correlated with that of [125I]iodosulpride (r = 0.98). 相似文献
997.
998.
An experimental model for canine visceral leishmaniasis 总被引:6,自引:1,他引:5
PEDRO ABRANCHES GABRIELA SANTOS-GOMES NURIT RACHAMIM† LENEA CAMPINO LIONEL F. SCHNUR‡ CHARLES L. JAFFE† 《Parasite immunology》1991,13(5):537-550
Seven mixed-breed dogs were challenged with either promastigotes or amastigotes of Leishmania donovani infantum strains recently isolated from naturally infected dogs. Different routes and numbers of parasites were utilized and each dog was monitored for at least 1 year post-infection. Anti-parasite specific antibody levels were measured by enzyme-linked immunosorbence, immunofluorescence, crossed-immune electrophoresis and Western blotting on crude antigen. Western blotting on two pure parasite proteins, dp72 and gp70-2, was also done. Mitogenic and antigen-specific stimulation of peripheral blood lymphocytes was monitored; and the haematological, clinical and parasitological parameters measured. Dogs challenged with amastigotes exhibited a more pronounced humoral response to leishmanial antigens. Only in one case was strong antigen-specific proliferation detected. Clinical signs of disease, including hypergammaglobulinaemia, enlarged lymph nodes and the presence of parasites, were also more apparent in the dogs challenged with amastigotes. None of the seven dogs died. Serum antibodies to leishmanial antigens were apparent between 1.5 to 3 months following challenge and correlated with the appearance of enlarged lymph nodes, hypergammaglobulinaemia and the presence of parasites in tissue biopsies. Serum antibodies remained chronically high in these dogs throughout the period of the study. Only one dog (1/3) challenged intravenously with promastigotes and the dog challenged intradermally with amastigotes produced transient antibody responses to leishmanial antigen. 相似文献
999.
利用气相色谱—质谱—计算机联用仪分析了云南省腾冲县产珠子参挥发油的成份,从中鉴定了27种化合物,测定了它们的相对含量,其中有10种倍半萜烯和一种倍半萜醇。 相似文献
1000.
本文运用模糊数学原理,对东台市1993年7月份市面上的全脂乳粉抽查监测结果进行卫生质量综合评价,结果令人满意,从而为乳粉卫生质量评比建立了客观有效的评价模型。 相似文献