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61.
Coronary arterial narrowing in Takayasu's aortitis. 总被引:4,自引:0,他引:4
P R Cipriano J F Silverman M G Perlroth R B Griepp L Wexler 《The American journal of cardiology》1977,39(5):744-750
A patient with Takayasu's aortitis and angina pectoris due to severe narrowing of the right and left coronary arterial ostia is described. Takayasu's arteritis produces a panaortitis, with thickening of the adventitia predominating, and an inflammatory cell infiltrate involving the adventitia, outer media and vasa vasorum. Narrowing of the coronary arteries in this disease is due to extension into these arteries of the processes of proliferation of the intima and contraction of the fibrotic media and adventitia that occur in the aorta. The distal coronary arteries usually do not manifest arteritis and are normal in caliber. Angina pectoris may be the first symptom of the disease if the coronary arteries are the initial site of severe arterial narrowing. The coronary arterial bypass graft operation is effective therapy for treating coronary arterial narrowing due to Takayasu's arteritis. 相似文献
62.
Histamine reduces boron neutron capture therapy‐induced mucositis in an oral precancer model 下载免费PDF全文
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65.
Restriction of cell lysis by homologous complement: II. Protection of erythrocytes against lysis by newly activated complement 总被引:1,自引:0,他引:1
Our previous work revealed that homologous complement (C) was ineffective in lysing antibody-sensitized erythrocytes (EA) even at high concentrations. It was also shown that activation of complement on homologous EA resulted in the binding of C9 and the formation of EA bearing complement proteins C1 through C9 (EAC1-9), yet few hemolytic sites were formed. Instead, as shown here, the formation of homologous EAC1-9 caused the cells to become resistant to lysis even by heterologous complement during a second incubation. In contrast, when homologous EAC1-8 were produced by incubating EA with C9-depleted serum, such intermediates were not protected against lysis by heterologous complement during a second incubation. Furthermore, homologous C9 on EAC1-9 was able to reduce the hemolytic efficiency of heterologous complement without blocking C activation and the formation of new C5b-9 complexes. Protection was not modified when homologous EAC1-9 were produced in one step, by incubation of EA with serum, or sequentially by adding C9 to EAC1-8. The minimum number of 9-sites required to confer a protective effect on EAC1-9 was less than 200 per cell. Thus, in addition to its known effect in heterologous cell killing, homologous C9 is capable of protecting homologous cells against inadvertent complement lysis. 相似文献
66.
Peripheral blood mononuclear cells from five patients with essential thrombocythemia (ET) were cultured in vitro to evaluate restricted megakaryocytic (CFU-Meg), myeloid (CFU-GM), and erythroid (BFU-E) progenitor cell development. Varying concentrations of aplastic canine serum served as the source of megakaryocyte colony-stimulating activity, and cultured megakaryocyte ploidy distributions were determined by Feulgen staining and microfluorometry. Megakaryocyte colony growth was strikingly abnormal in all five patients evaluated. Four of the 5 had a marked expansion in the concentration of circulating CFU-Meg and 3 of 4 manifested abnormalities in cultured megakaryocyte colony size (2 unusually large and 1 small). Unstimulated megakaryocyte colony growth was substantially increased in three patients. However, the fraction of megakaryocyte progenitors in cell cycle was near or below normal in all instances. Endomitotic megakaryocyte development was disordered in each of the four ET patients in whom it was evaluable. In normal subjects, mean megakaryocyte ploidy values vary biphasically with aplastic canine serum concentration and peak at 13.2 N following 12 to 15 days of culture. In contrast, day 12 mean ploidy values in cultures from the ET patients remained low at all aplastic canine serum concentrations and reached a maximum averaging only 8.4 N. Three patients were evaluated serially at extended culture durations of up to 21 days. The cultured megakaryocyte ploidy was unchanged during this interval for two of the patients. For the third patient, ploidy increased steadily, reaching abnormally high ploidy values by day 21. Progenitor cell expansion was limited to the megakaryocyte line in three patients. However, two patients had substantial increases in CFU-GM, one of whom also had a marked increase in BFU-E. There was no significant unstimulated colony growth by either CFU-GM or BFU-E. These data indicate that ET is usually characterized by an expansion in the concentration of circulating CFU-Meg in vivo which manifest both disordered replication and endoreduplication in vitro. 相似文献
67.
A Golan O Stolik S Wexler D Niv A Ber M P David 《International journal of fertility》1991,36(5):317-320
In an attempt to investigate the relative paucity of intraperitoneal adhesions after cesarean sections, we tested the effect of amniotic fluid on adhesion formation in rat model. Trauma was induced to the uterine serosa in 40 rats. Amniotic fluid was intraperitoneally instilled in 20 rats and saline in another 20 rats acting as controls. No inhibitory effect of the amniotic fluid could be demonstrated. The effect of the amniotic fluid and the saline solutions on fibroblastic proliferation was examined in vitro using fibroblastic cell cultures. No direct effect on fibroblast proliferation was found. It is concluded that it is not the direct effect of the spilled amniotic fluid that inhibits adhesion formation after the performance of cesarean sections. 相似文献
68.
Asymptomatic bacteriuria in normal and high-risk pregnancy 总被引:1,自引:0,他引:1
A Golan S Wexler A Amit D Gordon M P David 《European journal of obstetrics, gynecology, and reproductive biology》1989,33(2):101-108
A routine urine culture was performed in 1130 normal pregnant women and in 211 high-risk pregnancies (136 diabetics and 75 women with a previous urinary tract infection). Asymptomatic bacteriuria was found in 5.9% of the normal pregnancies, 12.5% among the diabetics and in 18.5% of the previous urinary tract infection patients. The higher incidence of a clinical urinary tract infection among patients with asymptomatic bacteriuria was found statistically significant (p less than 0.001) in all three groups. A high correlation was found between a negative urine culture in early pregnancy and the absence of development of cystitis and pyelonephritis in later pregnancy. The incidence of asymptomatic bacteriuria in normal pregnant women who developed cystitis later in pregnancy was 33.3% and in those developing pyelonephritis, 66%. In the two high-risk pregnancy groups, the incidence of asymptomatic bacteriuria among those developing clinical infection was even higher, 58.3 and 85.7%, respectively, among the diabetics, and 60 and 66.6% respectively, among the previous urinary tract infection patients. 相似文献
69.
A Golan O Stolik S Wexler R Langer A Ber M P David 《Acta obstetricia et gynecologica Scandinavica》1990,69(4):339-341
The effect of intraperitoneal application of prostaglandins F2 alpha and E2 on adhesion formation was studied in the rat after traumatizing to the uterine serosa. Prostaglandins applied locally were found to increase intraperitoneal adhesion formation at the injury site, in comparison with controls. The effect of intraperitoneal application of prostaglandins F2 alpha and E2 on fibroblastic proliferation was examined in vitro, by fibroblastic cell culture of rat kidney, human kidney and human prepuce. No direct effect of prostaglandins on fibroblast proliferation could be demonstrated. It is concluded that prostaglandins play an important role in the process of adhesion formation. This effect is not related to fibroblast proliferation. 相似文献
70.
EM Laursen A Juul S Lanng N H?iby C Koch J Müller NE Skakkebaek 《Archives of disease in childhood》1995,72(6):494-497
Cystic fibrosis is frequently accompanied by a catabolic condition with low body mass index caused by a number of disease complications. Insulin-like growth factor-I (IGF-I) is an anabolic hormone and an important marker of nutritional status, liver function, and linear growth. Available data on IGF-I in cystic fibrosis are sparse and conflicting. From 1990-3, 235 of our 240 patients (114 males, 121 females, median age 16.2 years, ranged 0.1-44.0 years) had IGF-I measured once by radioimmunoassay. IGF-I was significantly reduced compared with a healthy Scandinavian control population: mean (-2 SD to +2 SD) IGF-I SD score was -0.97 (-3.7 to 1.7) in males and -0.67 (-3.2 to 1.9) in females. Height SD score was -0.95 (-3.3 to 1.4) in males and -0.81 (-3.2 to 1.6) in females. In patients who were still in the growth period a significant correlation of IGF-I SD score to height SD score (r = 0.28, p < 0.001) was found. The low IGF-I concentrations may reflect the catabolic state of many patients with cystic fibrosis and play a part in their abnormal growth pattern. 相似文献