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排序方式: 共有2344条查询结果,搜索用时 15 毫秒
941.
942.
The development of two indices which can be used to characterize the acutely injured patient is presented. Evidence in support of the concept of characterizing injuries by the combined use of tissue disruption information and physiologic and biochemical response information is examined. 相似文献
943.
We have developed a polyacrylamide gradient gel electrophoretic method to quantitate apo-, mono-, and diferric transferrin based upon differences in their molecular size. Purified transferrin saturated to different extents (3% to 98%) with iron showed proportions of the three forms as predicted from an approximately random distribution of iron between the two metal-binding sites. The iron distributions in sera of 14 normal individuals similarly correlated with the predicted values. In contrast, 22 of 43 patients with diseases associated with abnormalities in iron or transferrin metabolism had a disproportionate increase in monoferric transferrin. This abnormality occurred in seven of nine patients who had received bone marrow transplants, seven of 14 with chronic liver disease, and eight of nine menstruating women with probable iron deficiency anemia. Interestingly, 11 patients with malabsorption or chronic renal disease had normal iron distributions. The finding of abnormal distributions of iron on transferrin suggests that gradient gel analysis may be a useful tool for studying the physiologic mechanisms controlling iron utilization. 相似文献
944.
945.
946.
M G Subramanian A G Sacco K S Moghissi D M Lawson R R Gala 《International journal of fertility》1991,36(6):367-371
Follicular fluid from mature preovulatory follicles was examined for the presence of prolactin (PRL) heterogeneity. Two pools of follicular fluid aspirates were used: one from follicles in which the ova were successfully fertilized in vitro and the other from follicles in which the ova were not successfully fertilized. Follicular fluid aspirates were concentrated by ultrafiltration and subjected to Sephadex G-100 gel chromatography. Fractions were assayed for immunoactive PRL by radioimmunoassay (RIA-PRL) and for bioactive PRL by the Nb2 lymphoma cell bioassay (BA-PRL). The major portion of RIA-PRL activity appeared as a low-molecular-weight component and accounted for 88% of the total PRL activity in the fertilized group and 87% in the unfertilized group. A high-molecular-weight component was also evident (12% and 13% for the two groups, respectively). The high-molecular-weight component in both groups was not active as PRL in the bioassay. These results demonstrate that while two immunoactive, heterogeneous forms of PRL exist in human follicular fluid when measured by RIA, it is only the low-molecular-weight form of PRL that is biologically active as established by Nb2 lymphoma cell bioassay. 相似文献
947.
Transforming growth factor-beta stimulates the expression of desmosomal proteins in bronchial epithelial cells. 总被引:4,自引:0,他引:4
M Yoshida D J Romberger M G Illig H Takizawa O Sacco J R Spurzem J H Sisson S I Rennard J D Beckmann 《American journal of respiratory cell and molecular biology》1992,6(4):439-445
Transforming growth factor-beta 1 (TGF-beta 1) has been shown to induce squamous differentiation of cultured airway epithelial cells. It has also been shown to increase expression of matrix proteins and integrin receptors in cell culture of these and other cells. However, it is unknown if TGF-beta 1 affects expression of genes encoding intercellular junctional proteins. Therefore, we have investigated the effect of TGF-beta 1 on the expression of proteins and mRNAs for desmoplakins (DPs) I and II, desmosomal plaque proteins. Fibronectin, known to be induced by TGF-beta 1 was used as a positive control and tubulin as a negative control. Twenty-four hours after TGF-beta 1 stimulation, DP I and II mRNA levels assessed by Northern blotting analysis had increased significantly (DP I mRNA, 1.8-fold, P less than 0.05; DP II mRNA, 2.4-fold, P less than 0.04), thereby indicating pretranslational regulation of DP expression. By comparison, mRNA for fibronectin increased 8.1-fold whereas mRNA for tubulin was unchanged. Immunofluorescence using the monoclonal anti-DP I and II antibodies revealed dramatic increased expression of punctate DP structures after exposure to TGF-beta 1. Immunoblot analyses with polyclonal anti-DP I antibodies showed increased levels of both DP I (250 kD) and DP II (215 kD), with the DP I increase being more pronounced (DP I, 2.5-fold; DP II, 1.4-fold at 48 h relative to controls), suggesting translational regulation by TGF-beta 1. This study therefore demonstrates the ability of TGF-beta 1 to alter cellular phenotype by altering expression of proteins involved in intercellular junctions.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
948.
949.
Vogelzang RL; Moel DI; Cohn RA; Donaldson JS; Langman CB; Nemcek AA Jr 《Radiology》1988,169(3):681-682
When acute renal vein thrombosis is associated with renal failure, aggressive therapy to eliminate the venous obstruction is indicated. There are reports of successful treatment of this condition with thrombolytic agents administered systemically or directly into the renal vein. Renal arterial administration of urokinase was used successfully to treat acute renal vein thrombosis associated with renal failure in a 9 1/2-year-old child. 相似文献
950.
C. Brignola M.D. P. Farruggia M.D. M. Campieri M.D. G. Bazzocchi M.D. A. Tragnone M.D. S. Pasquali M.D. P. Iannone M.D. G. Sacco M.D. G. A. Lanfranchi M.D. 《Diseases of the colon and rectum》1987,30(11):875-878
The clinical course of Crohn's disease in 131 patients was studied for a mean period of 4.2±3.2 years. The clinical activity
of the disease, expressed as percentage of patients per year in an active phase, is high in the first year (70.2 percent)
and progressively decreases during subsequent years (25 percent after seven years). The percentage of patients who needed
steroid treatment is high during the first year (68 percent) and falls to 19 percent after seven years. An operative risk
rate of 54 percent was registered, with a probability of reoperation equal to 34 percent. Clinical relapse after the first
surgery occurred in 70 percent of cases. The registered mortality was 6.9 percent, with a ratio of 6 to 1 between observed
and expected mortality. In conclusion, the disease, while showing a tendency to reduce its activity over the years, is burdened
by a risk of surgery and mortality which progressively increases with time 相似文献