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1.
Experiments on rats and mice were performed to study the effects of different substances modifying RES functions on hepatocyte proliferation. It was shown that as early as 24 hours after Kupffer cell (KC) overloading with colloidal iron particles the number of hepatocytes in mitosis increased. The mitotic rate increased by 32 h and decreased between 48 and 72 h following iron injection. Forty-eight h after injection of latex particles the hepatocyte mitotic peak could be identified. Twenty-four and 48 h after zymozan injection DNA synthesis in sinusoidal liver cells correspondingly increased. Hepatocytes in mitosis appeared 5 days later, reaching the peak value after 9 days followed by a decrease 12 days after zymozan injection. The depression of the hepatocyte mitotic rate was also observed 9 days after BCG and 15 days after prodigiozan injection. The data are suggestive of the importance of KC as potential inducers of hepatocyte proliferation.  相似文献   

2.
In the intact control baboons the plasma level of LH was elevated and reached a peak within 15 minutes after administration of 100 microgram synthetic LHRH. In addition, a second peak in plasma LH appeared within 90 minutes after LHRH injection. Supplementing these results, plasma level of estrogen was elevated within 30 minutes after LHRH injection. Subsequently, frontal deafferentation of the hypothalamus was performed in these baboons. After administration of 100 microgram synthetic LHRH in these frontally deafferented baboons the plasma level of LH was elevated and reached a peak within 15 minutes, as in the intact control baboons. However, there was no second LH peak within 90 minutes after LHRH injection, even though plasma estrogen was elevated within 30 minutes, as in the intact control baboons. It was found that the rostral hypothalamus in baboons is involved in the regulation of LHRH release which promotes to release LH within 90 minutes after LHRH injection.  相似文献   

3.
BACKGROUND: The mechanism of gene transfer into hepatocytes by the hydrodynamics-based transfection procedure is not clearly understood. It has been shown that, after a hydrodynamic injection, a large proportion of plasmid DNA remains intact in the liver where it is bound to plasma membrane and suggested that this DNA could be responsible for the efficiency of the transfection. METHODS: We have investigated the problem by giving mice a hydrodynamic injection of isotonic NaCl, followed at different time intervals by a conventional injection of DNA, cold or labelled with (35)S, with cDNA of luciferase as a reporter gene. Then, we determined the consequences of that dual injection on luciferase expression and on DNA uptake by the liver and its intracellular fate. By such experiments, it is possible to establish the time dependency of the induction of liver changes caused by a hydrodynamic injection on the one hand and the expression and DNA uptake and fate on the other. Moreover, some experiments have been performed on primary cultures of hepatocytes isolated after a hydrodynamic injection of DNA. RESULTS: When DNA is given to mice by a conventional injection a few seconds after an hydrodynamic injection of isotonic NaCl, luciferase expression in the liver is considerably lower than that observed after a single hydrodynamic injection of the plasmid. On the other hand, as assessed by the rate of DNA degradation and by centrifugation results obtained after injection of (35)S-DNA, the uptake and the intracellular fate of the bulk of DNA are similar whether DNA is administered by a single hydrodynamic injection or by a conventional injection given up to at least 2 h after a hydrodynamic injection of isotonic NaCl. Hepatocytes isolated a few minutes after a hydrodynamic injection exhibit a maximal expression that does not depend on the large amount of DNA that remains bound to the plasma membrane for a relatively long time. CONCLUSIONS: Our results show that the efficiency of hydrodynamics-based transfection depends on a process that takes place very quickly after injection and is not linked to a delay of DNA degradation and the persistence of a large proportion of DNA bound to hepatocytes of the plasma membrane, strongly suggesting that expression after a hydrodynamic injection is caused by a small proportion of DNA molecules that rapidly enter the cytosol probably by plasma membrane pores generated by the hydrodynamic pressure.  相似文献   

4.
复合氨基酸注射液如11S、14S中的氨基酸可使山梨醇的测定结果偏高6%,解决方法是将注射液通过磺酸型阳离子交换树脂柱,氨基酸成分在柱上被交换,山梨醇用水洗脱后测定。本方法对制订复合氨基酸类注射液的质量标准与确保产品质量均具有实际应用价值。  相似文献   

5.
Previous studies from this laboratory have shown that the injection of mice with an affinity-purified goat antibody to mouse IgD (GaM delta) induces T-independent polyclonal increases in: 1) B cell DNA synthesis, and 2) expression of surface Ia antigen and receptors for T helper factors, 1 to 2 days after injection. In addition, T-independent polyclonal increases in B cell number and IgG1 secretion are observed 6 to 7 days after injection. The administration of normal goat IgG (GIgG) along with GaM delta has been shown to augment GaM delta-induced polyclonal IgG1 secretion. To obtain information about the characteristics of the T help that is required for polyclonal antibody production in this model system, we investigated: 1) the length of the period during which GaM delta must be present to induce day 7 polyclonal antibody production, and 2) the kinetics of the induction of splenic T cell DNA synthesis. We found that GaM delta can be neutralized 3 days after injection by the administration of IgD without decreasing day 7 polyclonal IgG1 secretion, as long as mice are given GIgG at the time that GaM delta is neutralized. In contrast, polyclonal IgG1 secretion is greatly inhibited if GaM delta is neutralized 1 to 2 days after injection or if GaM delta is neutralized 3 days after injection, but GIgG is not administered at this time. Because GIgG can stimulate activated GIgG-specific T cells to secrete helper factors, but, unlike GaM delta cannot focus GIgG-specific T help polyclonally onto B cells, these findings suggest that nonspecific T help, rather than antigen-specific T help, is required in this system after day 3 for the induction of polyclonal IgG1 secretion. Determination of the kinetics of the induction of T cell DNA synthesis in this system by in vivo [3H] thymidine incorporation studies, as well as dual laser fluorescence-activated cell sorter analysis of T and B cell DNA content, indicate that T cells are induced to synthesize DNA 2 days after GaM delta injection and reach plateau rates of DNA synthesis 3 days after injection. Taken together, the GaM delta neutralization experiments and DNA synthesis studies suggest that one reason that GaM delta is required for 3 days in this system is to allow maximal activation of GIgG-specific T cells, which when stimulated later by GIgG secrete nonantigen-specific helper factors that induce GaM delta-activated B cells to secrete IgG1.  相似文献   

6.
李丽荣  刘彦希  刘花  王树越  周凤吉 《生物磁学》2011,(18):3534-3535,3543
目的:探讨瘦型手背掌骨间隙静脉输液拔针后有效按压方法。方法:采用自身对照法,对瘦型手背掌骨间隙静脉输液拔针后采用两种不同的按压方法,左侧手背为对照组,采用传统的拇指指腹按压法;右侧手背为实验组,采用拇指挠侧面按压法。对两组静脉输液拔针后的出血及淤血的发生率进行比较。结果:对照组出血及皮下淤血的发生率明显高于实验组,差异有显著性意义(P〈0.05)。结论:对瘦型手背掌骨间隙静脉输液拔针后采用拇挠侧面按压法优于传统拇指指腹按压法,值得推广应用。  相似文献   

7.
Using an aqueous solution of sodium benzyl penicillin as the model substance, a comparison was made in cattle between absorption after intramuscular injection, and after subcutaneous and deep injection into the dewlap. The duration of supposed therapeutically effective serum concentrations using the 2 dewlap routes was longer than for the intramuscular route, although maximum concentrations were lower. The applicability of injection into the dewlap, especially the subcutaneous route, is discussed in relation to intramuscular injection.  相似文献   

8.
目的:探讨瘦型手背掌骨间隙静脉输液拔针后有效按压方法。方法:采用自身对照法,对瘦型手背掌骨间隙静脉输液拔针后采用两种不同的按压方法,左侧手背为对照组,采用传统的拇指指腹按压法;右侧手背为实验组,采用拇指挠侧面按压法。对两组静脉输液拔针后的出血及淤血的发生率进行比较。结果:对照组出血及皮下淤血的发生率明显高于实验组,差异有显著性意义(P<0.05)。结论:对瘦型手背掌骨间隙静脉输液拔针后采用拇挠侧面按压法优于传统拇指指腹按压法,值得推广应用。  相似文献   

9.
Electron microscopy with application of specific fluorescent histochemical reaction of Falck, as well as some methods of impregnation made it possible to indentify enterochromaffin cells in the stomach of hyperthyroid rats and the rats after cortisone injection under the conditions ox hyperfunction of the thyroid gland. After 20 days of L-thyroxin injection, and after 10 days of hydrocortisone injection, preceded by L-thyroxin, the amount of enterochromaffin cells in the epithelial layer of the gastric mucosa were noted to increase that was accompanied by simultaneous increase of the number of secretory argyrophil granules in their cytoplasm. Simultaneous injection of L-thyroxin and hydrocortisone, while not decreasing statistically significant amount of the cells, produced degradation of their cytoplasm.  相似文献   

10.
Regulation of the systemic immune response by visible light and the eye   总被引:3,自引:0,他引:3  
The injection of certain antigens into the anterior chamber (AC) of the eye results in the induction of antigen-specific suppressor T cells (Ts cells), which inhibit systemic delayed-type hypersensitivity (DTH). We have previously shown that down-regulation by Ts cells after AC injection with 2,4,6-trinitrophenol (TNP)-coupled spleen cells (TNP-Spl) is initiated by the intraocular activation of Ts inducer cells. These cells activate T suppressor-effector cells in the spleen that are responsible for suppressed DTH. With dark- and light-reared mice (Balb/c), we show that visible light has a direct effect on the intraocular T cell reaction that leads to systemic suppression. Our results show that if light is prevented from reaching the eye by dark rearing, by placing light-reared animals in the dark after AC injection, or by closing the eyelids of light-reared animals after AC injection, Ts cells are not activated. We show that light is responsible for establishing conditions in the eye that cause the preferential activation of Ts cells. The intraocular conditions established by light are not developmentally mandated as is visual development, but can be eliminated in adult light-reared animals by placing them in the dark for 18 h after AC injection. These conditions can also be induced in adult dark-reared animals by returning them to the light for just over 24 h before AC injection. These studies have important implications for understanding intraocular immune responses and possibly for the treatment of eye disease.  相似文献   

11.
Minimizing the pain of local anesthesia   总被引:1,自引:0,他引:1  
We studied the effect of depth of lidocaine injection into the skin, rate of injection, and temperature of the solution on pain experienced. The intervals of onset and duration of anesthesia were also evaluated. Intracutaneous instillation of lidocaine at body temperature (37 degrees C) is no less painful than injection at room temperature (21 degrees C), but superficial wheal-producing dermal injection is uniformly much more painful than that into the deep dermal-subcutaneous tissue region. Rapid injection almost always hurts more than slow. Full anesthesia to pinprick is produced immediately with superficial injection and is present 5 to 6 minutes after deep injection. We suggest that the best method for minimizing the discomfort of inducing local anesthesia is to use a syringe fitted with a No. 30 needle and to inject the smallest amount necessary slowly into the deep dermal-subcutaneous tissue as the needle is being slowly withdrawn.  相似文献   

12.
Partial liver resection (two-thirds) performed in (CBA X C57BL)F1 mice 2-4 or 24 h after intravenous injection of 2 mg zymozan led to retardation of the formation of mononuclear infiltrates in the liver and the lung. In control sham-operated animals, the first signs of infiltration appeared on the 2nd, whereas in mice with partial liver resection ( PLR ) on the 5th day after zymozan -induced stimulation of liver macrophages. If mice underwent PLR 5 days after zymozan injection, the preformed mononuclear infiltrates experienced the reverse development. PLR did not abolish monocytosis which was observed after zymozan injection. On the other hand, when mice received hydrocortisone in a dose of 125 mg/kg, the zymozan -induced infiltration in the liver as well as monocytosis were blocked. It is assumed that depression of mononuclear infiltration in the liver and the lung after liver resection is linked with a specific effect of proliferating hepatocytes rather than with the stress-induced mobilization of glucocorticoids.  相似文献   

13.
The injection of non-homologous cytoplasm into any strain of large free-living amoebae leads to a 60% inhibition of division amongst recipient cells. When the post-microsomal supernatant fraction of Amoeba discoides was injected into A. proteus, this inhibition of division was as high as 95%. The incorporation of tritiated precursors, either [3H]uridine or 3H-amino acids, into these inhibited amoebae was studied at various times after the injection of the inhibitory material using autoradiography. When cells were grown in [3H]uridine, autoradiographs indicated that RNA synthesis had ceased 2 days after the injection of non-homologous material. However, if [3H]uridine was injected into the inhibited cells, some synthesis of RNA could be detected up to 4 days after the injection of inhibitor. These results suggested that uptake of [3H]uridine was impaired and that one site of action of the inhibitory molecules was RNA synthesis for membrane components. Experiments with a variety of 3H-amino acids suggested that protein synthesis continued for at least 9 days after the injection of non-homologous cytoplasm, and that in these cells some informational RNA molecules were long-lived. There seemed to be accumulation of material containing [3H]lysine in the nuclei of control cells taken at random from cultures, and this was seen in the nuclei of inhibited cells 1 day after injection. However, 2 days after the injection of inhibitor, no accumulation of [3H]lysine-containing material was found in the nuclei.  相似文献   

14.
Male and female hamsters and a female rabbit were injected with 241Pu citrate. The hamsters were killed serially at 15 min, 2 hours, 1 day and 10 days after injection, and the rabbit 1 week after injection. The gonads were examined for 241Pu by tissue-section autoradiography. Soon after injection the plutonium was concentrated by the contents of atretic Graafian follicles and by thecal rings in the ovary, but was found to be dispersed throughout the testes. It is suggested that the disperse distribution in the testes which is only seen soon after injection may be an artefact of tissue processing. One day after injection, plutonium was accumulated by macrophages in both the follicles of the ovary and in the interstitial tissue of the testes. Macrophages containing plutonium later migrated away from the aretic ovarian follicles towards the ovarian medulla. This pattern of distribution and redistribution in the ovary is regarded as likely to lower the effective dose from a-emitting plutonium isotopes to the viable oocytes. No migration of macrophages was seen in the testes. Histochemical staining methods revealed the presence of acid protoglycans, including chondroitin sulphate, and glycoproteins at the sites of plutonium concentration in the ovary. These molecules are regarded as likely receptor sites for plutonium. In the testes no acidic carbohydrates were found, and it is suggested that the initial binding site for plutonium may be a compound lipid. This was deduced from the apparent inability of the interstitial tissue of the testes to bind plutonium in situ.  相似文献   

15.
In experiments on mice 3H-spiperone binding after intraperitoneal injection was studied. The binding of 3H-spiperone was saturable in the frontal cortex and subcortical structures, whereas in the cerebellum, the amount of radioactivity increased in a linear manner and was referred to as nonspecific binding. The neuroleptics haloperidol, chlorpromazine and sulpiride given 0.5 h before 3H-spiperone displaced 3H-spiperone in the subcortical structures in a dose-related manner. Although the level of the specific 3H-spiperone binding after intraperitoneal injection was lower than after intravenous injection, the intraperitoneal method is simpler, well reproduced and given results comparable with the intravenous method.  相似文献   

16.
Mononuclear phagocytes of the Rat adrenal cortex were identified by light microscopy after injection of Chinese ink or colloidal iron (Imferon 200). They may be found as endothelial, periendothelial or intracapillary cells. The number of mononuclear phagocytes was much greater in the adult than in the young Rat, with a significant peak 3 hrs. after injection of Chinese ink in the young Rat and two peaks, 4 and 12 hrs. after injection in the adult.  相似文献   

17.
1. Drinking was induced in water-replete quail 5-10 min after intravenous injection of hypertonic NaCl (0.69 osmol/l) or sucrose (1.06 osmol/l), but hypertonic urea (2.78 osmol/l) failed to induce drinking. 2. The birds drank approximately the amount required to dilute the injected solutes to isotonicity for each given dose of NaCl or sucrose. 3. The plasma angiotensin II level decreased after injection of 7% NaCl (2.5 osmol/l), but it increased after injection of an equi-osmolar solution of sucrose (65%). 4. Plasma osmolality and Na+ concentration returned quickly to control levels, and then decreased further, after injection of 7% NaCl or 65% sucrose. 5. Blood volume and blood pressure increased immediately after injection of 7% NaCl or 65% sucrose. 6. These results show that drinking is induced after injection of hypertonic solutions exclusively by cellular dehydration, and other regulatory mechanisms for thirst, such as extracellular dehydration and the renin-angiotensin system, are rather inhibitory after injection of hypertonic NaCl.  相似文献   

18.
Induced Bactericidal Response in the Hagfish   总被引:1,自引:0,他引:1       下载免费PDF全文
Hagfish were shown to be capable of synthesizing bactericidins after injection of gram-negative bacteria. The bactericidins could be detected as early as 2 days after injection. The degree of specificity was not as impressive as in mammalian systems.  相似文献   

19.
Lysozymelike activity is present in the hemocytes and cell-free hemolymph of Spodoptera eridania. Its level remains essentially constant during larval development and can be induced by injection of various foreign materials. Serum bacteriolytic activity rises 24 hr after injection of saline, BSA, bacteria, bacterial endotoxin (LPS), latex particles, or sham injection. However, the magnitude and subsequent duration of the response depends on the nature of the injected material. The response is transient following sham injection or injection of soluble substances, such as saline and BSA, as compared to treatment with latex or bacteria. Both soluble and insoluble fractions of bacterial LPS preparations stimulated the lysozyme response. The response to a single injection of E. coli LPS was dose dependent and persisted for at least 5 days; however, additional injections had no effect on serum lysozyme level. The basal intracellular lysozyme level was significantly increased by E. coli LPS injection. Lysozyme release by hemocytes was proportional to intracellular concentration and did not increase after phagocytic stimulation of hemocytes.  相似文献   

20.
Subcutaneous injection of L-cycloserine resulted in a 28% reduction in cerebroside levels in mouse brain but had no effect on the levels of gangliosides. In contrast, intraperitoneal injection results in a reduction of ganglioside as well as cerebroside + sulfatide levels. The route of injection influenced the degree of 3-ketodihydrosphingosine synthase inhibition. Intraperitoneal injection caused a rapid decrease in synthase activity followed by recovery over 48 hr, whereas subcutaneous injection resulted in no inhibition over this time; only after daily injection for a week was synthase activity reduced 35%. One week following cessation of L-cycloserine administration, enzyme activity had recovered, whereas the cerebroside level continued to fall. All lipids and enzymes showed normal levels 3 weeks post-cycloserine administration. L-[3H]serine incorporation into glycolipids showed that cerebroside synthesis was most affected, whereas sulfatide synthesis was less affected. One week after cessation of cycloserine treatment, cerebroside synthesis was still severely inhibited, whereas sulfatide levels were near normal. Two weeks after cessation of L-cycloserine administration, synthesis of these glycolipids was similar to that of controls.  相似文献   

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