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排序方式: 共有363条查询结果,搜索用时 15 毫秒
1.
S S Grigorian A D Pritsker E K Onufrieva D G Chireshkin F I Ershov 《Voprosy virusologii》1991,36(5):407-409
The influence of various interferon concentrations in vitro on alpha- and gamma-interferon production by lymphocytes of children suffering from respiratory papillomatosis was studied for optimization of interferon therapy. Most of the children with clinical improvement after interferon treatment showed proportional dependence of alpha-interferon production upon exogenous interferon concentrations and stability of gamma-interferon production. In children without clinical improvement, initial production of both interferons was reduced significantly in the absence of IF in the medium, but no changes occurred when exogenous interferon was present in the medium. The test proposed here may be used for the determination of patients' sensitivity to interferon and for individualization of interferon treatment schedules in other long-lasting recurrent diseases. 相似文献
2.
3.
F I Ershov T M Sokolova E B Tazulakhova A A Kadyrova U Kisling A S Novokhatsky 《Acta virologica》1979,23(1):32-39
A comparative analysis of interferon and antiviral protein messenger RNAs was carried out. Differences in their biological activities and sedimentation coefficients were found. In RNA preparations from superinduced cells (cells treated with poly(I).poly(C) and antimetabolites) and from cells treated with interferon, messenger RNAs possesing interferon and antiviral activities were detected. The results suggest the existence of two types of mRNA (for interferon and antiviral protein, respectively) and support the hypothetic model of interferon action via an antiviral protein. 相似文献
4.
The impact of hydrosalpinx (HSPX) on in-vitro fertilization (IVF) outcome
has recently been the subject of intense debate. Most, but not all, studies
have reported decreased implantation and pregnancy rates and increased
early pregnancy loss in HSPX patients. This has led to prophylactic
salpingectomies prior to IVF in HSPX patients despite the lack of any
prospective studies to suggest that any improvement will occur. Women with
HSPX constitute a heterogeneous population because some conceive easily
with IVF while others do not until after surgical correction. HSPX also
increases in size with ovarian stimulation, and can cause implantation
failure by fluid reflux into the uterine cavity. Careful assessment of the
endometrial lining is mandatory in HSPX to rule out fluid reflux from the
HSPX. We present two case reports of patients whose HSPX enlarged with
ovarian stimulation, causing fluid reflux into the uterine cavity which was
only noted after human chorionic gonadotrophin (HCG) administration.
相似文献
5.
Antiproliferative effect of interferon inducers 总被引:1,自引:0,他引:1
The antiproliferative effect of clinically promising interferon inducers, phage f2 ambermutant dsRNA, polyguacyl, tiloron, Tash-4, was demonstrated in Raji lymphoblastoid cells. Concentrations of the inducers producing death of 48-66% of Raji cells were determined to be: for dsRNA, 200 micrograms/ml; polyguacyl, 400 micrograms/ml; tiloron, 100 micrograms/ml; Tash-4, 200 micrograms/ml, which corresponded to the antiproliferative effect of 200 units/ml of alpha-interferon and 40 units/ml of gamma-interferon. No antiproliferative effect was observed at dsRNA, polyguacyl, and Tash-4 concentrations below 100 micrograms/ml. None of the inducers exerted the antiproliferative effect on the selected concentrations on normal human diploid cells. The results obtained explain the antitumorigenic effect of these inducers, demonstrated previously. 相似文献
6.
The influence of microsomal mixed function oxidases (MFO) on the biotransformation of pesticides was investigated in experiments with perfusion of isolated rat livers and in whole animals. The pesticides examined were 3 organophosphorus insecticides (OP): S-propyl-O-phenyl-O-ethylthiophosphate (heterophos), a mixture of O,O-dimethyl-O-cyclohexylthionphosphate and O,S-dimethyl-O-cyclohexylthiolphosphate (cyclophos), and dithiophosphonate. The indices of NADPH-dependent hydroxylating systems measured in the microsomal fraction of rat liver homogenates were the activity of aniline hydroxylase, aminopyrine demethylase and the amount of cytochrome P-450. It was shown that not only did the specific chemical structure of the OP and induction or inhibition of MFO determine OP activation and detoxification (and thus its biological action), but also the route and frequency of exposure could influence these parameters. 相似文献
7.
8.
S N Suntsov N N Ozeretskovskaia S S Grigorian A M Shcherbakov F I Ershov 《Meditsinskaia parazitologiia i parazitarnye bolezni》1990,(6):43-44
In 11 patients with Echinococcus multilocularis infection the blood levels of alpha-interferon (alpha-IF) and gamma-interferon (gamma-IF) were measured using vesical stomatitis virus culture. In patients with the disease the contents of alpha- and gamma-IF were significantly (p less than 0.01) lower than in healthy controls: 392 +/- 101.6 and 101.6 +/- 20.9 U/ml and 1024 +/- 83.2 and 187 +/- 16.9 U/ml, respectively. The lower levels of alpha- and gamma-IF were found in patients with multiorgan damages including the lungs, as compared with the liver and abdomen infestation: alpha-IF 160 +/- 56.6, gamma-IF 88 +/- 24.0 and 525.7 +/- 124.3 and 109 +/- 18.3 (p less than 0.01), respectively. The similar data have been found in patients with hydatid disease (S. N. Suntsov et al., 1990). After 5 to 6 courses of mebendazole therapy in a dose of 50 mg/kg body weight dai y for 30 days with 30-day intervals there was a tendency to a slight elevation of cytokines levels (S. N. Suntsov et al., 1990), as seen in hydatid disease. The estimation of IF levels in multilocular echinococcosis infection may be of prognostic value and perhaps for the evaluation of the efficacy of surgical and chemotherapeutic treatment. 相似文献
9.
Tomy dos Santos Rolo Alexey Ershov Thomas van de Kamp Tilo Baumbach 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(11):3921-3926
Scientific cinematography using ultrafast optical imaging is a common tool to study motion. In opaque organisms or structures, X-ray radiography captures sequences of 2D projections to visualize morphological dynamics, but for many applications full four-dimensional (4D) spatiotemporal information is highly desirable. We introduce in vivo X-ray cine-tomography as a 4D imaging technique developed to study real-time dynamics in small living organisms with micrometer spatial resolution and subsecond time resolution. The method enables insights into the physiology of small animals by tracking the 4D morphological dynamics of minute anatomical features as demonstrated in this work by the analysis of fast-moving screw-and-nut–type weevil hip joints. The presented method can be applied to a broad range of biological specimens and biotechnological processes.The best method to study morphological changes of anatomic features and physiological processes is to observe their dynamics in 4D, that is, in real time and in 3D space. To achieve this we have developed in vivo X-ray cine-tomography to gain access to morphological dynamics with unrivaled 4D spatiotemporal resolution. This opens the way to a wide range of hitherto inaccessible, systematic investigations of small animals and biological internal processes such as breathing, circulation, digestion (1), reproduction, and locomotion (2).At the micrometer resolution range, state-of-the-art optical imaging techniques can achieve high magnifications to visualize tissues and even individual cells for 4D studies. These methods however are confined to transparent or fluorescent objects, or are limited either by low penetration depth <1 mm or poor time resolution (3). For optically opaque living organisms X-ray imaging methods are highly appropriate due to the penetrating ability of the radiation. Modern synchrotron radiation facilities provide brilliant and partially coherent radiation suitable for high-resolution volume imaging methods such as X-ray computed microtomography (SR-µCT). For static specimens SR-µCT has proven to be a powerful tool to study small animal morphology in 3D (4–6). The benefits of various physical contrast mechanisms, high spatial resolution, and short measuring times, as well as enormous sample throughput compared with laboratory X-ray setups, have led to its widespread use in life sciences.Real-time in vivo X-ray imaging with micrometer spatial resolution was realized so far by recording time sequences of 2D projection radiographs of different organisms (1, 6, 7), providing time information about functional dynamics but losing any information about the third spatial dimension.Recently, 4D in vivo X-ray experiments have been performed to study cell migration in frog embryos (8, 9) using tomographic sequences of a few seconds exposure time per tomogram interrupted by longer nonexposure time slots. In this way the authors followed relatively slow dynamics and morphological changes during embryonic development with 2-µm resolution over total time intervals of several hours. The fastest 4D time series yet reported were realized with a temporal resolution of 0.5 s and spatial resolution of 25 µm (10), applied to a living caterpillar used as test specimen for imaging, but without any analysis of dynamics.In this paper, we demonstrate the quantitative 4D investigation of morphological dynamics by in vivo X-ray 4D cine-tomography, introduced here as the combination of ultrafast SR-µCT and motion analysis procedures. Using this approach allows us to investigate previously inaccessible 3D morphological dynamics in small animals, presently with feature sizes in the micrometer range and with temporal resolution down to a few tens of milliseconds. In the past, ultrafast in vivo imaging was hardly possible for such applications, due to the strongly competing requirements for simultaneous high contrast, high signal-to-noise ratio (SNR), and concurrent low radiation dose, as well as the need for simultaneous high spatial resolution and maximum temporal resolution.In the following we describe how in vivo X-ray 4D cine-tomography meets the above challenges by optimizing image contrast, SNR, and spatial and temporal resolution in the ultrafast SR-µCT system and by establishing a dedicated data analysis pipeline, all within a unified framework (Fig. S1). We demonstrate the potential of the technique by investigating morphological dynamics in fast-moving weevils, focusing here on the exoskeletal joints. 相似文献
10.
Experience with combined operations for stomach cancer in combination with pancreatoduodenal resection or total duodenopancreatectomy is presented. Immediate and long-term results of 10 pancreatoduodenal resections and 5 total duodenopancreatectomies are analyzed. There were 2 lethal outcomes. Complicated postoperative period was seen in 7 patients. During the first year of follow-up 6 of 13 operated patients died due to dissemination. After total pancreatectomy severe homeostatic disorders were seen. Prognosis after pancreatoduodenal resection is better when the tumor involves the duodenum than when it invades the pancreas. Subtotal resection of the stomach and gastrectomy in combination with duodenopancreatosplenectomy lead to unfavorable functional results and have bad long-term prognosis. 相似文献