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431.
KH Ramsey GS Miranpuri CE Poulsen NB Marthakis LM Braune GI Byrne 《Canadian Metallurgical Quarterly》1998,66(2):835-838
Mice lacking inducible nitric oxide synthase (iNOS) or treated with iNOS inhibitors resolved chlamydial genital tract infections. Additionally, treatment of primary murine cell cultures with gamma interferon restricted chlamydial growth in the absence of nitric oxide. From these results, iNOS activity is unnecessary for the resolution of chlamydial genital tract infections in mice and inhibition of chlamydial growth in culture. 相似文献
432.
GI Kutuzova GK Frank VIu Makeev NG Esipova RV Polozov 《Canadian Metallurgical Quarterly》1997,42(2):354-362
The synthesis of proinflammatory cytokines involves members of the mitogen-activated protein (MAP) kinase stress pathway, particularly p38 MAP kinase and c-jun NH2-terminal kinase. In this report we used hyperosmotic stress to study changes in steady-state mRNA levels and synthesis of proinflammatory cytokines in freshly obtained human peripheral blood mononuclear cells (PBMC) in vitro. There was no evidence of interleukin (IL)-8 gene expression in freshly obtained human blood despite 30 cycles of amplification of reverse-transcribed mRNA using the polymerase chain reaction. In contrast, exposure of PBMC to hyperosmotic conditions (330-410 mOsM) by the addition of NaCl to tissue culture medium induced gene expression for IL-1 alpha, IL-1 beta, and IL-8. Routine tissue culture medium is hyperosmotic (305 mOsM) compared to human plasma (280-295 mOsM), but decreasing the osmolarity to the physiological range resulted in a 50% reduction in baseline IL-8 synthesis (P < 0.001). Although hyperosmotically induced accumulation of steady-state mRNA levels for IL-1 alpha and IL-1 beta increased 50- and 7-fold over control, respectively, these were poorly translated into each respective cytokine. However, in PBMC stimulated by hyperosmotic stress, the addition of femtomolar concentrations of bacterial lipopolysaccharide, IL-1, or 1% normal human serum resulted in a synergistic synthesis (at least twice that expected) of IL-1 alpha, IL-1 beta, TNF-alpha, and IL-8. 相似文献
433.
The pattern of cervical dilatation during labour in 100 patients with previous lower segment caesarean section (LSCS) was determined in a prospective partographic study. Eighty-four subjects delivered successfully by vaginal route. The mean initial dilatation rate (IDR) and average dilatation rate (ADR) were 0.884 cm/hour and 1.255 cm/hour respectively. The mean IDR and ADR of the patients who delivered vaginally were 0.96 cm/hour and 1.41 cm/hour respectively, while of those who required repeat LSCS mean IDR was 0.44 cm/hour and mean ADR was 0.42 cm/hour. Hence ADR in cases who required repeat LSCS was significantly slower as compared to those who delivered vaginally (p < 0.01). Most (87.5%) of the cases who required repeat LSCS crossed the alert line as compared to 34.5% of patients who delivered vaginally. The mean admission delivery interval (ADI) was 9.45 +/- 4.29 hours in patients with no previous vaginal delivery and 8.02 +/- 4.83 hours in patients with previous vaginal delivery. The mean durations of 1st and 2nd stages of labour were 11.8 +/- 5.35 hours and 29.4 +/- 27.3 minutes respectively. It is concluded that partographic evaluation is an important aspect in management of labour of such patients. 相似文献
434.
435.
As a requisite for a physiological and immunological investigation, reagents were developed that facilitated the identification and purification of Chlamydia trachomatis hsp10 (chsp10). Monoclonal antibodies that specifically recognize chsp10 were generated with multiple-antigen peptides (MAPs) to promote recognition of Chlamydia-specific epitopes. MAP2, containing amino acids 54 to 69 of the hsp10 sequence, elicited strong antibody responses after immunization of BALB/c mice. Monoclonal antibodies from several cloned hybridomas reacted on immunoblots with an approximately 15-kDa chlamydial protein and recombinant chsp10. Because of its strict specificity for chsp10, monoclonal antibody M1.2 was selected for routine use. M1.2 reacted by immunoblot with the hsp10s of several C. trachomatis strains but not with Chlamydia psittaci hsp10 or Escherichia coli homolog GroES, suggesting that M1.2 recognizes a species-specific epitope. Recombinant chsp10 was purified by immunoaffinity chromatography with M1.2. For large-scale purification, chsp10 was appended with a C-terminal six-histidine tag for purification by nickel chelate affinity chromatography. The hypA gene encoding the chsp10 of C. trachomatis serovar E/Bour was cloned into the pQE-60 vector (QIAGEN, Inc.) following PCR amplification from genomic DNA. E. coli DH5 transformants were screened for chsp10 expression by colony immunoblotting with M1.2, were tested for nickel matrix binding, and were sequenced. The sequence of serovar E/Bour chsp10 was found to be closely homologous to those of hsp10s of other chlamydiae. Purified chsp10 and specific anti-chsp10 monoclonal antibodies will be useful for investigating the biological and immunological roles of hsp10 in chlamydial infections. 相似文献
436.
OBJECTIVES: The aim of this study was to examine the effect of chronic medical conditions on cognitive function in a sample of community-dwelling elderly (N = 4528). METHODS: A checklist of 18 chronic medical conditions was used to determine whether respondents were suffering from specific disease states. The Mini Mental Status Examination (MMSE) was administered to assess cognitive functioning. RESULTS: Statistically controlling for the effects of age, education and depression, respondents with asthma/bronchitis and stroke had a tendency to perform worse on the MMSE than those without these conditions. None of the 18 medical conditions was associated with a greater proportion of respondents scoring below the cutoff for cognitive dysfunction. CONCLUSION: It appears that--with the possible exception of stroke and asthma/bronchitis-cognitive function in community-dwelling elderly is not consistently affected by specific disease states. 相似文献
437.
LE Hann GI Getrajdman KT Brown AM Bach JB Teitcher Y Fong LH Blumgart 《Canadian Metallurgical Quarterly》1996,167(4):1017-1021
OBJECTIVE: This study was performed to evaluate the association between hepatic lobar atrophy, bile duct obstruction, and portal vein obstruction. MATERIALS AND METHODS: Thirty cases of hepatic lobar atrophy identified on angiography with CT during arterial portography from August 1992 to March 1995 were retrospectively reviewed by two independent observers. Cases were evaluated for vascular patency and bile duct obstruction. Malignant diagnoses were present in 28 of 30 patients. RESULTS: Twenty-two patients (73%) had atrophy in the left lobe and eight patients (27%) had right lobar atrophy. Portal vein obstruction was unilateral and confined to the atrophic lobe in 26 patients (87%). In contrast, bile duct obstruction was bilateral in 23 patients (77%) and in only four patients (13%) was it isolated to the atrophic lobe. The correlation between atrophy and portal vein obstruction was significant, with 90% sensitivity, 97% specificity, and 96% positive predictive value (p < .00001). For the correlation between atrophy and biliary obstruction, the sensitivity of angiography with CT during arterial portography was 90%, specificity was 23%, and positive predictive value was 54% (p = .17). CONCLUSION: Hepatic lobar atrophy usually occurs in the setting of combined biliary and portal vein obstruction. A significant correlation exists between hepatic lobar atrophy and ipsilateral portal vein obstruction. 相似文献
438.
439.
JS Katz GI Wolfe WW Bryan CE Jackson AA Amato RJ Barohn 《Canadian Metallurgical Quarterly》1997,48(3):700-707
We performed detailed electrophysiologic studies on 16 patients with clinically defined multifocal motor neuropathy and found a wide spectrum of demyelinating features. Only five patients (31%) had conduction block in one or more nerves. However, in 15 patients (94%) at least one nerve showed other features of demyelination. We also noted a significant degree of superimposed axonal degeneration in 15 patients. Eight patients (50%) had individual nerves with pure axonal injury, despite the presence of demyelinating features in other nerves. Antiganglioside antibodies were elevated in four of five patients with conduction block and five of 11 patients without conduction block. We conclude that multifocal motor neuropathy is characterized electrophysiologically by a wide spectrum of axonal and demyelinating features. Diagnostic criteria requiring conduction block may lead to underdiagnosis of this potentially treatable neuropathy. 相似文献
440.
GI Klebanov IuO Teselkin IV Babenkova TIu Bashkueva TM Modestova LS Steklova IuA Vladimirov 《Canadian Metallurgical Quarterly》1997,123(4):395-398
We examined whether X radiation induces a particular deletion in the mitochondrial DNA (mtDNA) of the cells of two human squamous cell carcinoma lines with different sensitivity to radiation and in a radiosensitive ataxia telangiectasia (AT) cell line. We used polymerase chain reaction (PCR) to quantify the accumulation of a particular 4977-bp deletion (delta mtDNA4977). PCR products of delta mtDNA4977 were detectable after exposure to 10 Gy in the radioresistant squamous cell carcinoma cells, 2 Gy in the radiosensitive squamous cell carcinoma cells and 1 Gy in the radiosensitive AT cells. These observations suggest that ionizing radiation induces the delta mtDNA4977 in human cells and that the radiation doses required to induce this deletion reflect the sensitivity of cells to radiation. 相似文献