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1.
Smoking and stroke.   总被引:2,自引:0,他引:2  
The purpose of this review is to evaluate literature published since 1978 on the association between smoking and stroke. Two cohort studies found a dose-response relationship between the amount of cigarettes smoked per day and the relative risk of stroke. Also, two of the cohort studies found that when smoking ceased, the risk of stroke lessened (p less than 0.001). Nine case-control studies found a significant association between smoking and stroke for men and women. The biological association between smoking and stroke is plausible and several epidemiologic studies are supportive of this thesis. Additional, well-designed epidemiologic studies with a sufficient sample size to detect reasonably small odds ratios or relative risks (thus providing adequate statistical power) are warranted.  相似文献   
2.
We evaluated anti-Toxoplasma gondii IgM-reactive pregnant women seen at a high-risk pregnancy outpatient clinic. From March 2005 to January 2008 in Paraná, Brazil, pregnant women seen by the Brazilian Public Health System, in any gestational period, who were anti-T. gondii IgM-positive, were followed. Clinical symptoms were noted, and tests performed including IgA, IgG avidity, ultrasonogram, and amniocentesis (PCR/inoculation in mice). Of 75 patients, 8 showed low, 3 intermediate and 31 high IgG avidity. Of those who underwent the avidity test, 31 (70.5%) were in the second trimester of pregnancy. Thirty-two (42.7%) pregnant women received specific treatment. Six received triple combination treatment; in three, tachyzoites were isolated, although only one was PCR-positive, showing changes in the cerebral sonogram, borderline IgA, and the Sabin tetrad. One fetus died, and one non-reactive IgM pregnant woman showed ocular recurrence. The municipality of residence, contact with cats during adulthood, and ingestion of unpasteurized milk were shown to be important risk factors. Congenital toxoplasmosis was observed in a pregnancy referred late for treatment. Follow-up of children born to mothers with diagnosed or suspected acute toxoplasmosis is crucial in the management of the changes that toxoplasmosis may cause.  相似文献   
3.
Immunological studies were performed in 87 patients with chyluria referred to our clinic from January 1982 to December 1988. White blood cell count in 78 patients was 5210.3 +/- 1440.9/mm3. The fraction and the number of lymphocyte were 18.7 +/- 9.5% and 934.1 +/- 521.6/mm3, respectively: they were lower than normal limit. The percentages of T and B lymphocytes studied in 46 patients were 79.3% +/- 11.2% (normal range: 76-86) and 10.4 +/- 7.9% (normal range: 8-16), respectively: both lymphocytes tended to decrease in percentage. Lymphocyte blast formation stimulated with phytohemagglutinin (PHA) was carried out in 20 patients. The mean of the blast formation was 17410.0 +/- 10275.1 c.p.m. (normal range: 377700-62400), and much lower than normal value. Of 22 patients who had PPD skin test, only 9 (40.9%) were positive. These findings signified that cellular immunity was suppressed in patients with chyluria. On the other hand, the value of immunoglobulin was within normal range (IgG: 1325.3 +/- 475.6 mg/dl, IgA: 242.0 +/- 98.3 mg/dl, IgM 130.4 +/- 95.9 mg/dl). Study on the values of laboratory examinations showed statistically positive correlation between total lymphocyte population and T cell number, and between total lymphocyte population and lymphocyte blast formation. In patients with chyluria, serious sequelae have not been reported. However, care should be taken for possible opportunistic infection and, particularly, malignant tumors because suppression of cellular immunity may be one of the promoting factors of malignant tumors.  相似文献   
4.
Clarithromycin (TE-031, A-56268), a new macrolide antibiotic agent, was evaluated bacteriologically and clinically for its efficacy and safety in pediatrics by a study group organized with pediatricians from all over the country. A summary of the results of the evaluation is as follows. 1. Absorption and excretion Pharmacokinetics of TE-031 was examined by single oral administration of 10% granules and 50 mg tablets at doses of 1, 5, 10 and 15 mg/kg. There were no significant differences between 10% granules and 50 mg tablets, and between administrations before and after meal. Peaks and half-life periods of blood level of TE-031 given once at doses of 5, 10 and 15 mg/kg (10% granules) before meal were 1.58, 4.37 and 3.79 micrograms/ml, and 2.53, 3.17 and 2.20 hours, respectively, and the urinary excretion in 6 hours after the administration were about 20-30%. 2. Antibacterial effects TE-031 was proved to have excellent antibacterial effect, i.e., inhibiting growth over 80% of strains of Streptococcus pneumoniae and Streptococcus pyogenes at 0.10 micrograms/ml, Branhamella catarrhalis at 0.39 micrograms/ml, and Campylobacter jejuni at 0.78 micrograms/ml. Against Staphylococcus aureus, TE-031 showed very similar activity spectrum to EM, and EM resistant strains were also resistant to TE-031. 3. Clinical results A total of 764 cases was studied. Clinical effects of TE-031 were evaluated in 717 cases out of the 764, excluding drop-outs and cases which did not meet specified protocols. Clinically, efficacies of TE-031 were "excellent" in 265 cases and "good" in 161 cases out of 453 cases of Group A in which causal agents were identified, with an efficacy rate of 94.0%, and out of 264 cases of Group B in which pathogens were not detected, clinical effects of TE-031 were "excellent" in 115 cases and "good" in 124 cases, with an efficacy rate of 90.5%. In terms of clinical effects of TE-031 classified by diseases when Group A and B were combined, efficacy rates were 91.6% for upper respiratory tract infection (217/237), 90.0% for bacterial pneumonia (108/120), 97.4% for Mycoplasma pneumonia (111/114), 100% for Chlamydia pneumonia (4/4), 85.0% for pertussis (34/40), 100% for scarlet fever (16/16), 83.9% for skin and soft tissue infection (26/31), and 98.9% for Campylobacter enteritis (87/88).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
5.
The cation transport and regulatory volume decrease (RVD) were investigated in the red blood cells (RBCs) of northern fur seals (Callorhinus ursinus). Extracellular Ca-dependent Na efflux was increased to threefold by hypotonicity. K–Cl cotransport activity was not detected by hypotonic medium, but measured only by nitrite or N-ethylmaleimide stimulation. RBCs were restored to their original volume after being swollen in hypoosmotic medium with Ca, though this recovery was inhibited by the addition of quinidine. Based on these results, Na/Ca exchange transporter played the major role in the regulatory volume decrease in the RBCs of northern fur seals. H. Fujise has passed away.  相似文献   
6.
Validity and parent-child agreement of the Social Phobia and Anxiety Inventory for Children-Parent Report (SPAI-C-P) were examined in a racially diverse sample of 158 students in Grades 5 through 8 (87 girls; ages 10 to 14; M = 11.53) and their caregivers. Children completed the Social Phobia and Anxiety Inventory for Children (SPAI-C), and caregivers completed the SPAI-C-P and the Child Behavior Checklist (CBCL). The SPAI-C-P demonstrated good internal consistency and was significantly correlated with child self-reported social anxiety. Confirmatory factor analysis supported a 3-factor model over a 5-factor model, and concurrent validity was evidenced. Implications and directions for future research are discussed.  相似文献   
7.
We developed a new simple assay for the quantitation of the activities of drugs against intracellular Legionella pneumophila. The cells of a murine macrophage-like cell line (J774.1 cells) allowed the intracellular growth and replication of the bacteria, which ultimately resulted in cell death. The infected J774.1 cell monolayers in 96-well microplates were first treated with antibiotics and were further cultured for 72 h. The number of viable J774.1 cells in each well was quantified by a colorimetric assay with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and an enzyme-linked immunosorbent assay reader. The number of growing bacteria in each well was also determined by counting the numbers of CFU on buffered charcoal yeast extract-α agar plates. Viable J774.1 cell counts, determined by the colorimetric assay, were inversely proportional to the number of intracellular replicating bacteria. The minimum extracellular concentrations (MIECs) of 24 antibiotics causing inhibition of intracellular growth of L. pneumophila were determined by the colorimetric assay system. The MIECs of beta-lactams and aminoglycosides were markedly higher than the MICs in buffered yeast extract-α broth. The MIECs of macrolides, fluoroquinolones, rifampin, and minocycline were similar to the respective MICs. According to their intracellular activities, clarithromycin and sparfloxacin were the most potent among the macrolides or fluoroquinolones tested in this study. Our results indicated that the MTT assay system allows comparative and quantitative evaluations of the intracellular activities of antibiotics and efficient processing of a large number of samples.  相似文献   
8.
The etiological agents of diarrhea in Vientiane, Lao People’s Democratic Republic (Lao PDR), were studied in the period from October 1996 to August 1997. A total of 880 patients with diarrhea visiting medical facilities were examined for Shigella, Salmonella, diarrheagenic Escherichia coli, Vibrio, Aeromonas, Campylobacter, and rotavirus. Shigella spp., heat-stable enterotoxin (ST)-producing E. coli, and serogroup-based enteropathogenic E. coli were found to be the main organisms causing diarrhea in Vientiane, with frequencies of 16.8% (148 of 880), 17.2% (111 of 645), and 11.0% (97 of 880), respectively. Relatively low incidences were observed in the cases of Salmonella spp., (0.6%; 5 of 880), Campylobacter spp. (4.4%; 39 of 880), and rotavirus (6.1%; 9 of 148), and no isolates of V. cholerae O1 or O139 or Aeromonas were recovered. An analysis of the incidences of enteropathogens with respect to age and seasonal variations demonstrated that the frequencies of isolation of Shigella spp. and heat-labile enterotoxin-producing E. coli were significantly higher in those aged 1 to 5 years than in those younger than 1 year of age and those older than 5 years of age (P < 0.0001 and P < 0.05, respectively) and that the frequencies of isolation of Shigella spp. and ST-producing E. coli were significantly higher in the rainy season than in the dry season (P < 0.005 and P < 0.001, respectively). Almost all strains of Shigella spp. tested were resistant to ampicillin, tetracycline, and erythromycin and were susceptible to cefdinir and ofloxacin. This is the first intensive and longitudinal study to define the etiologic agents of diarrheal diseases in Lao PDR.  相似文献   
9.
H H Higa  G N Rogers  J C Paulson 《Virology》1985,144(1):279-282
This report examines the ability of three sialic acids (SA), N-acetylneuraminic acid (NeuAc), N-glycollylneuraminic acid (NeuGc), and 9-O-acetyl-N-acetylneuraminic acid (9-O-Ac-NeuAc), to serve as receptor determinants for 18 human and animal influenza type A viruses. Viruses were compared by agglutination of receptor-modified erythrocytes containing either the Sa alpha 2,6Gal or the SA alpha 2,3Gal linkages with each of the three sialic acids. Individual isolates differed markedly in their ability to agglutinate cells containing NeuAc, NeuGc, and 9-O-Ac-NeuAc. The results suggest that recognition of the various sialic acids is an important factor in analysis of the receptor specificity of influenza virus hemagglutinins.  相似文献   
10.
BACKGROUND: We have previously shown that fisetin, a flavonol, inhibits IL-4 and IL-13 synthesis by allergen- or anti-IgE-antibody-stimulated basophils. This time, we investigated the inhibition of IL-4 and IL-13 production by basophils by other flavonoids and attempted to determine the fundamental structure of flavonoids related to inhibition. We additionally investigated whether flavonoids suppress leukotriene C4 synthesis by basophils and IL-4 synthesis by T cells in response to anti-CD3 antibody. METHODS: Highly purified peripheral basophils were stimulated for 12 h with anti-IgE antibody alone or anti-IgE antibody plus IL-3 in the presence of various concentrations of 18 different kinds of flavones and flavonols. IL-4 and IL-13 concentrations in the supernatants were then measured. Leukotriene C4 synthesis was also measured after basophils were stimulated for 1 h in the presence of flavonoids. Regarding the inhibitory activity of flavonoids on IL-4 synthesis by T cells, peripheral blood mononuclear cells were cultured with flavonoids in anti-CD3-antibody-bound plates for 2 days. RESULTS: Luteolin, fisetin and apigenin were found to be the strongest inhibitors of both IL-4 and IL-13 production by basophils but did not affect leukotriene C4 synthesis. At higher concentrations, these flavonoids suppressed IL-4 production by T cells. Based on a hierarchy of inhibitory activity, the basic structure for IL-4 inhibition by basophils was determined. CONCLUSIONS: Due to the inhibitory activity of flavonoids on IL-4 and IL-13 synthesis, it can be expected that the intake of flavonoids, depending on the quantity and quality, may ameliorate allergic symptoms or prevent the onset of allergic diseases.  相似文献   
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