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81.
Our study of 16 normal term, breast-fed infants documents real-time ultrasound as a technique for evaluating the oral portion of the sucking mechanism in infants. We also describe the mechanics of sucking used by the infants during breast-feeding. 相似文献
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83.
Mullerian duct cyst: diagnosis with MR imaging 总被引:1,自引:0,他引:1
84.
The effect of purified human fibroblast interferon on primary and secondary colony formation by blast progenitors from the peripheral blood of patients with acute myelogenous leukemia was examined. Interferon inhibited blast progenitors and normal granulocyte/macrophage progenitors (CFU-C) in a dose-dependent manner. The magnitude of this effect on blast progenitors and CFU was similar. Interferon also inhibited secondary plating of blast progenitors (self- renewal). This effect was in marked contrast to the effect of adriamycin, which reduced primary plating efficiency of blast progenitors but did not affect self-renewal. Inhibition of blast progenitor proliferation by interferon was markedly reduced when interferon was added after 24 hr of culture and was absent when added after 72 hr. Inhibition of self-renewal was observed even when interferon was added at 72 hr. We conclude that interferon inhibits both primary proliferation and self-renewal of blast progenitors and that this effect is not due to reduction in the number of primary colonies. These experiments provide an example of how cell culture techniques may be used to test antitumor agents for effects on important cellular events other than general cytotoxicity. 相似文献
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MP Busch ; EA Operskalski ; JW Mosley ; CE Stevens ; ER Schiff ; SH Kleinman ; H Lee ; M Lee ; M Harris 《Transfusion》1994,34(10):858-864
BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1- infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high- risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts. 相似文献
88.
C Oliveira RA Navarro-Xavier EA Anjos-Vallota JO Martins VLF Silveira LRC Gon?alves MS Araújo G Motta P Sannomiya MLV Oliva 《British journal of pharmacology》2010,161(4):899-910
BACKGROUND AND PURPOSE
The serine and cysteine peptidase inhibitor, BbCI, isolated from Bauhinia bauhinioides seeds, is similar to the classical plant Kunitz inhibitor, STI, but lacks disulphide bridges and methionine residues. BbCI blocks activity of the serine peptidases, elastase (Kiapp 5.3 nM) and cathepsin G (Kiapp 160.0 nM), and the cysteine peptidase cathepsin L (Kiapp 0.2 nM). These three peptidases play important roles in the inflammatory process.EXPERIMENTAL APPROACH
We measured the effects of BbCI on paw oedema and on leucocyte accumulation in pleurisy, both induced by carrageenan. Leucocyte–endothelial cell interactions in scrotal microvasculature in Wistar rats were investigated using intravital microscopy. Cytokine levels in pleural exudate and serum were measured by elisa.KEY RESULTS
Pretreatment of the animals with BbCI (2.5 mg·kg−1), 30 min before carrageenan-induced inflammation, effectively reduced paw oedema and bradykinin release, neutrophil migration into the pleural cavity. The number of rolling, adhered and migrated leucocytes at the spermatic fascia microcirculation following carrageenan injection into the scrotum were reduced by BbCI pretreatment. Furthermore, levels of the rat chemokine cytokine-induced neutrophil chemo-attractant-1 were significantly reduced in both pleural exudates and serum from animals pretreated with BbCI. Levels of interleukin-1β or tumour necrosis factor-α, however, did not change.CONCLUSIONS AND IMPLICATIONS
Taken together, our data suggest that the anti-inflammatory properties of BbCI may be useful in investigations of other pathological processes in which human neutrophil elastase, cathepsin G and cathepsin L play important roles. 相似文献89.