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61.
All of the five commercially available benzylpenicillin preparations obtained from different sources and a PcG preparation prepared by filtration of a commercial PcG on Sephadex G10 elicited the systemic anaphylactic reactions in guinea pigs which had been immunized with benzylpenicilloyl (BPO)-Ascaris extract conjugate (BPO-As) mixed with aluminum hydroxide gel. These preparations could evoke no such reactions in guinea pigs immunized with BPO-bovine gamma globulin conjugate (BPO-BGG) emulsified with complete Freund's adjuvant. The severity of the systemic anaphylactic reactions correlated significantly with the titers of either 8-day passive cutaneous anaphylactic (8-day PCA) reactions or 4-hr PCA reactions evoked with the same benzylpenicillin preparations. In vitro benzylpenicillin preparation contracted the tracheas of the guinea pigs immunized with BPO-As. These results indicated that the commercially available benzylpenicillin preparations have enough antigenicity to evoke systemic anaphylactic reactions in guinea pigs immunized with BPO-As mixed with aluminum hydroxide gel. Such guinea pigs represent an animal model for investigation of penicillin allergy.  相似文献   
62.
The present study examined the temporal pattern and localization of interleukin-1, tumor necrosis factor-alpha, and inducible nitric oxide synthase expression in lung tissue undergoing foreign body granuloma formation. Pulmonary granulomas were induced by the intratracheal injection of dextran beads into genetically high granuloma responder, carrying Bcgs (BALB/c), and low responder, carrying Bcgr (C3H/HeJ and DBA/2), mice. There was a pattern of sequential expression of these molecules in BALB/c mice. Thus, interleukin-1 alpha and inducible nitric oxide synthase were induced mostly in the cells accumulated around the beads and also in some bronchiolar epithelial cells during the early phase (1 to 3 days), whereas tumor necrosis factor-alpha was induced in the cells around the beads at the later resolution phase (3 to 7 days). By contrast, in low responder mice, an increase in the expression of interleukin-1 alpha and inducible nitric oxide synthase was detected in lung macrophages as well as in alveolar cells and bronchiolar epithelial cells on day 1, but that of tumor necrosis factor-alpha was not detected throughout the period. These results together with our previous findings on cytokine activity in granuloma extract suggest that interleukin-1 and nitric oxide produced by recruited macrophages may take part in the early, macrophage-dependent phase of granuloma formation whereas tumor necrosis factor-alpha may be more crucial as a mediator responsible for the difference in innate resistance or susceptibility to granuloma formation.  相似文献   
63.
The effects of surgical operation on the generation of cell-mediated cytotoxicity in mixed cell cultures were studied in patients with various carcinomas or benign lesions. Peripheral blood mononuclear cells from patients were cultured with B lymphoblastoid cell line Raji in mixed culture, and the induced cytotoxicity was measured by 51Cr release assay. In 15 patients with various carcinomas, the capacity of cells to generate cytotoxic cells was significantly depressed 1, 3 and 6 days after surgery, as compared to that before surgery. It returned to the pre-operative level by the 8th post-operative day. In eight patients with benign lesions, significant decrease in cytotoxic cell activity was observed 3 and 6 days after operation. At the 8th day, however, there was a significant increase in the generated cytotoxicity. The depressed generation of cytotoxic cells 3 days after surgery could be abrogated by removal of adherent cells from the responding cell population. This effect could be partially reconstituted by addition of separated, autologous adherent cells back to the responding non-adherent cell culture. These results demonstrate that suppressor cells, presumably monocytes, may be responsible for the depressed generation of cytotoxic cells after surgery.  相似文献   
64.
This is a report of a 27-year-old woman with an unusual de novo chromosomal abnormality. Mosaicism was identified in peripheral blood cells examined by standard G-bands by trypsin using Giemsa (GTG) analysis and fluorescence in situ hybridization (FISH) analysis with chromosome-18 region-specific probes, 46,XX,del(18)(pter → q21.33:)[41], 46,XX,r(18)(::p11.21 → q21.33::)[8], and 46,XX,der(18)(pter → q21.33::p11.21 → pter)[1]. On the other hand, the karyotype of periodontal ligament fibroblasts was nonmosaic, 46,XX, der(18)(pter → q21.33::p11.21 → pter)[50]. All cell lines appeared to be missing a portion of 18q (q21.33 → qter). The pattern of the dup(18p)/del(18q) in the rod configuration raises the possibility of an inversion in chromosome 18 in one of the parents. However, no chromosomal anomaly was detected in either parent. The most probable explanation is that de novo rod and ring configurations arose simultaneously from an intrachromosomal exchange. The unique phenotype of this patient, which included primary hypothyroidism and primary hypogonadism, is discussed in relation to her karyotype.  相似文献   
65.
Renal functions were examined in 102 patients with yusho in 1988, Frequencies of proteinuria, microhematuria and history of renal diseases were not different from 20 age-matched controls. The means of blood urea nitrogen, serum creatinine and serum uric acid levels of yusho patients did not differ from those of controls. The levels of serum beta 2-microglobulin and its urinary excretion showed no difference between two groups. Serum concentrations of sodium, potassium, chloride, calcium and phosphorus revealed no abnormality in all patients except for one who had hypophosphatemia. Urinary excretions of phosphorus, however, were significantly higher in yusho patients than in controls. Serum PCB levels, which were still higher in yusho patients, did not correlate with urinary excretions of phosphorus. The mechanism and the clinical significance of this phenomenon remain to be elucidated.  相似文献   
66.
Modified PCR-RFLP method for HLA-DPB1 and -DQA1 genotyping.   总被引:17,自引:0,他引:17  
We previously developed a new technique for HLA class II genotyping by digestion of polymerase chain reaction-amplified genes with restriction endonucleases (PCR-RFLP method). This PCR-RFLP method is an efficient and convenient typing technique for class II alleles. However, small fragments or bands located close to each other on polyacrylamide gels sometimes prevent precise analysis of the RFLP bands. Furthermore, the restriction enzymes we have reported in the previous papers are not sufficient to identify the genotypes of all heterozygous individuals. Here, we report an improved PCR-RFLP method using some informative restriction enzymes which have either a single cleavage site or, alternatively, no cleavage site in the amplified DNA region, depending on the HLA alleles, making reading of RFLP band patterns much easier. Each second exon of the HLA-DQA1 or -DPB1 gene was selectively amplified from genomic DNAs of 70 HLA-homozygous B-cell lines and 100 healthy Japanese by PCR. Amplified DNAs were digested with restriction endonucleases and then subjected to electrophoresis assaying simply for cutting, or no cutting, of the DNA. ApaLI, HphI, BsaJI, FokI, MboII and Mn1I can discriminate eight alleles of the DQA1 gene. Similarly 19 alleles of the DPB1 gene can be discriminated with Bsp1286I, FokI, DdeI, BsaJI, BssHII, Cfr13I, RsaI, EcoNI, and AvaII enzymes. This modified PCR-RFLP method can be successfully applied to heterozygotes. Thus, the method is technically simpler and more practical for routine HLA typing work than our previous PCR-RFLP method.  相似文献   
67.
68.
In Japan, the use of amantadine for treatment of influenza A virus infection was not accepted until November 1998, although it was widely used for treatment of Parkinsonism. Since then, we have monitored the emergence of amantadine-resistant viruses and isolated two viruses from patients on long-term treatment with amantadine.  相似文献   
69.
Five autopsy cases of thrombotic microangiopathy, including 3 cases associated with acute promyelocytic leukaemia, were examined macroscopically, light-and electronmicroscopically.
The so-called hyaline thrombi In thrombotic microangiopathy were composed of fibrin and its degenerative products. Thrombocytes and other blood cells were not seen in the thrombi.
At the site of the formation of a thrombus, there was no conspicuous change in the walls of the capillaries and arterioles. It was considered, therefore, that the intravascular deposition of fibrin was the primary event in the development of thrombotic microangiopathy.
In regard to the distribution and morphologic findings, there was no basic difference between the microthrombi in cases associated with acute promyelocytic leukaemia and those without it.
The bone marrow and some other organs in cases of thrombotic microangiopathy associated with acute promyelocytic leukaemia macroscopically revealed a green colour. Many thrombi composed of leukaemic cells and fibrin were found in the pulmonary arteries of these cases. Furthermore, prominent erythrophagocytosis in the bone marrow and lymph nodes was a common finding in these cases.  相似文献   
70.
PROBLEM: Tumor necrosis factor-alpha (TNF-alpha) is present in human placental and uterine cells at the early and late stages of gestation and promotes the regulation of trophoblast growth and invasion. We evaluated whether TNF-alpha levels in the placenta and blood of pre-eclamptic women differed from those with normal pregnancies. METHOD OF STUDY: The subjects were 39 pregnant women carrying single fetuses (21 normal-pregnant and 18 pre-eclamptic patients). Their average gestational age at entry was 38-39 weeks. Peripheral blood was collected before the onset of labor and separated serum was stored at -20 degrees C. A tissue segment of the placenta was cut and frozen in liquid nitrogen immediately after delivery at -80 degrees C. The frozen placental tissue was added to phosphate-buffered saline. The tissue was fully homogenized and centrifuged. Separated supernatant was stored at -80 degrees C. TNF-alpha levels in separated serum and TNF-alpha and total protein (TP) levels in separated supernatant were measured. The presence of TNF-alpha in the placenta was evaluated by immunohistochemistry in five pre-eclamptic and five normal-pregnant patients. RESULTS: Serum TNF-alpha levels were higher in pre-eclampsia than in normal pregnancies. However, TNF-alpha/TP levels in the placenta did not differ significantly between the two groups. As for TNF-alpha immunostaining of trophoblastic cells in the placenta, it was weak in three and moderate in two of the normal pregnancies, while it was absent in two, weak in one, and moderate in two in the pre-eclampsia group. CONCLUSIONS: We demonstrated no significant increase in TNF-alpha/TP levels in the placenta in pre-eclampsia despite a significant increase in serum TNF-alpha levels. There was no strong immunostaining for TNF-alpha detected by immunohistochemistry in the pre-eclampsia group. These findings suggest that TNF-alpha in the placenta is not a key cytokine to interfere with normal trophoblast invasion into the myometrium in pre-eclampsia, and that sources other than the placenta may contribute to the elevated levels of TNF-alpha found in the circulation of pre-eclamptic patients.  相似文献   
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