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81.
Opportunistic infections in the oral cavity of the elderly may increase the incidence of systemic disease. The objective of this study was to investigate the differences in the oral bacterial flora between dependent elderly (inpatients) and independent elderly (community-dwelling residents). After multiple variables were taken into account, inpatients had significantly lower detection rates than community-dwelling residents for alpha-streptococci (p < 0.001) and Neisseria (p 0.004), and higher detection rates for Pseudomonas aeruginosa (p 0.024), methicillin-resistant Staphylococcus aureus (MRSA) (p 0.011) and Actinomyces spp. (p 0.005). Among inpatients, the requirement for a high degree of care was related negatively to detection of alpha-streptococci, but was related significantly to detection of P. aeruginosa (p 0.018) or MRSA (p 0.004). Tube-fed inpatients had a significantly lower detection rate for alpha-streptococci (p 0.041) and a higher detection rate for P. aeruginosa (p 0.004) than those who did not require tube feeding. Inpatients with a history of antibiotic use had a significantly lower detection rate for alpha-streptococci (p 0.049) and a higher detection rate for MRSA (p 0.007) than those without a history of antibiotic use. The detection rates for P. aeruginosa or MRSA in inpatients without alpha-streptococci were higher than in inpatients with alpha-streptococci after controlling for age and gender (P. aeruginosa, p 0.006; MRSA, p 0.001). Overall, detection of alpha-streptococci had an inverse correlation with the detection of P. aeruginosa and MRSA in the oral cavity and is likely to be an indicator of pathogenic bacterial infection.  相似文献   
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Hepatitis B virus (HBV) genotypes have distinct geographical distribution. HBV sequences among hepatitis B carriers in Malawi have not been evaluated thus far. HBsAg serotype and genotype of HBV was determined in 20 serum samples from Malawian chronic HBV carriers, and two complete genomes and 13 entire pre-S2/S genes were sequenced directly. Genotype A HBV isolates were found in all of the samples, and serotype with adw2 and ayw2 were detected in three and 17 samples, respectively. In phylogenetic analyses, two complete genomes were classified into a subgroup A' that was described previously in South African isolates of the virus, and were separated from HBV isolates in Western countries with nucleotide differences ranging from 4.1-6.2%. The separation of subgroup A' was also evident in the tree topology of the entire pre-S1/S2, X and precore/core region, but not evident in the small-S region. The nucleotide divergences in subgroup A' were higher than those among genotype A without subgroup A' in the complete genomes as well as each of four open reading frames. All of the 13 pre-S2/S sequences were classified into the subgroup A', and clustered with known HBV isolates with ayw2 in carriers from South Africa and Zimbabwe. Three amino acids in the pre-S2/S gene were characteristic of subgroup A' with ayw2. In conclusion, unique HBV isolates of subgroup A' with ayw2 are prevalent in Malawi, and subgroup A' with a relatively higher nucleotide diversity may be a HBV isolate characteristic of the indigenous population of some African countries.  相似文献   
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E Abraham  G Yoshihara 《Chest》1990,98(6):1445-1449
Cardiorespiratory values were measured in ten patients with severe respiratory failure on volume controlled and pressure controlled ventilation. Tidal volume, respirator rate, PEEP, auto-PEEP, inspiratory:expiratory ratio (1:2) and FIo2 were maintained at the same value for both ventilatory modalities. Changing from VCV to PCV was associated with significant improvements in PaO2, oxygen delivery, and tissue oxygen consumption. Peak inspiratory pressure fell. There were no significant changes in other cardiorespiratory values, such as arterial blood pressure, nor in ventilatory measurements, such as mean airway pressure, associated with the use of PCV. These results suggest that PCV may be a beneficial ventilatory modality in the treatment of severe respiratory failure since it results in improvement in arterial oxygenation, tissue oxygen delivery and utilization without any concomitant adverse effects on other hemodynamic or ventilatory factors.  相似文献   
86.

Objectives

This study aimed to evaluate the efficacy of radiation therapy for pelvic lymph node metastasis from uterine cervical cancer and identify an optimal radiation regimen.

Methods

A total of 111 metastatic pelvic lymph nodes, ranging from 11 to 56 mm (median, 25 mm) on CT/MRI, in 62 patients with uterine cervical cancer were treated initially with curative radiation therapy, with 46 patients receiving concurrent chemotherapy. Total radiation doses ranged from 45 to 61.2 Gy (median, 50.4 Gy) in 1.8–2 Gy (median, 1.8 Gy) fractions.

Results

At a median follow-up of 33 months, 46 of the 62 patients survived. Only 2 irradiated lymph nodes, 24 and 28 mm in diameter, in 1 patient progressed after irradiation alone with 50.4 Gy in 1.8 Gy fractions. All 33 metastatic lymph nodes ≥ 30 mm in diameter were controlled by irradiation at a median dose of 55.8 Gy. The 3-year lymph node-progression free rates were 98.2% in all 62 patients and 98.0% in all 111 metastatic lymph nodes. Except for transient hematologic reactions, 2 patients developed grade ≥ 3 therapy-related toxicities, 1 with an ulcer and the other with perforation of the sigmoid colon. In addition, 2 patients experienced ileus after irradiation.

Conclusions

Radiation therapy effectively controlled pelvic lymph node metastases in patients with uterine cervical cancer, with most nodes < 24 mm in diameter controlled by total doses of 50.4 Gy in 1.8 Gy fractions and larger nodes controlled by 55.8 Gy, particularly with concurrent chemotherapy. Higher doses to metastatic lymph nodes may increase intestinal toxicities.  相似文献   
87.
BACKGROUND: Human leukocyte antigen (HLA) antibodies are defined as complement (C) fixing and clinically relevant based upon the complement-dependent cytotoxicity (CDC) test. However, the sub-lytic activation of individual C components is of critical biologic significance. The requirements of HLA antibodies to activate human C are not known. METHODS: IgG, IgM, IgG subclasses, and human C3b deposition upon T cells were evaluated by flow cytometry with sera from HLA-sensitized patients and human monoclonal HLA antibodies. RESULTS: Comparative studies showed that there was poor correlation between the amount of IgG on target cells and their ability to produce CDC. Human C3b deposition was influenced more by the particular serum/cell combination under study than by the amount of IgG, with some combinations showing high IgG and low C3b and others showing low IgG and high C3b. IgG1 was the predominant IgG subclass in all patients. The other subclasses were low or undetectable and did not correlate with C3b deposition. Human monoclonal HLA antibodies, mostly IgG1, did not activate human C efficiently despite high IgG binding. However, combinations of two monoclonal antibodies to different epitopes of the same antigen did produce significant C3b deposition. CONCLUSIONS: Contrary to common assumptions, CDC, IgG binding, and IgG subclass are poor predictors of human C activation by HLA antibodies. The mix of specificities in a given serum and the antigens of a particular target cell appear to determine the efficiency of C activation. Measuring both antibody and C3b deposition (or other C component) may improve the assessment of donor-recipient compatibility.  相似文献   
88.
STUDY DESIGN: A prospective study was conducted on the surgical procedures for lumbar disc herniation. OBJECTIVE: The objective of this study is to investigate the surgical outcomes of different methods when performed by the same surgeon, using a prospective study. BACKGROUND: Macro discectomy is widely known as a common surgical procedure for lumbar disc herniation, while microdiscectomy in place of Caspar technique (the Caspar method) and microendoscopic discectomy by a posterior approach are reported as less invasive surgical methods for this condition. However, there have not been a significant number of prospective studies conducted to compare different surgical procedures for lumbar disc herniation. MATERIALS AND METHODS: The target of our study was a group of 62 patients (male: 43, female: 19) who underwent surgery by macro discectomy (A group) and 57 patients (male: 33, female: 24) who underwent surgery by microdiscectomy in place of Caspar technique (B group). The mean ages at surgery were 34 (14 to 62) years and 41 (18 to 65) years respectively, and the mean duration of follow-up was 2 years and 8 months (12 months to 4 years). For all patients, the surgery was performed by 1 of the authors. The items investigated were the operation time, amount of bleeding, duration of hospitalization, amount of analgesic agent used after surgery, pre- and postoperative scores based on judgment criteria for treatment of lumbar spine disorders established by the Japanese Orthopaedic Association score, visual analog scales (VAS, 0 to 10) for lumbago before surgery and at discharge, VAS for sciatica before surgery and at discharge, perioperative complications, and cases requiring further surgery. RESULTS: There were no significant differences between the 2 surgical procedures in the frequency of use of an analgesic agent after surgery, the pre- and postoperative Japanese Orthopaedic Association scores or postoperative VAS for sciatica. Statistically significant differences were observed in the operation time, amount of bleeding, duration of hospitalization, and postoperative VAS for lumbar pain, but the differences were not large, and may not have been clinically significant. CONCLUSIONS: For herniotomy for lumbar disc herniation, both macro discectomy and microdiscectomy are appropriate, as long as surgeons have mastery of the procedures.  相似文献   
89.
Detection of AN6520 Ag/Ab in human sera had indicated a close association with non-A, non-B hepatitis (NANBH). In this study, we investigated the immunochemical nature of AN6520 Ag and measured the amounts in various human and chimpanzee organs in order to clarify the association with NANBH. AN6520 Ag was found to be composed of polypeptide(s) with an apparent molecular weight of 45,000 daltons (45 kD), which are noncovalently linked together. Human antibodies in convalescent sera from NANBH patients as well as monoclonal antibodies were found to recognize only the high-order structure of the antigen, whereas rabbit antibody recognized both the high-order structure and the reduced form of 45 kD polypeptide(s). AN6520 Ag could be detected in most of the livers tested including those without any liver damage and fetal livers; their amounts varied considerably from each other. The antigen could be detected also in organs other than liver, but in contrast to liver, the amounts were small and did not vary as much between individuals. From the data of immunoblotting using rabbit antibody, our observed variation of antigen content in liver was considered to be due to the difference in expression of 45 kD polypeptide(s). Although no specific relationship was found between the amount of the antigen in liver and NANBH, the antigen was found to increase several times in livers of chimpanzees after the inoculation of NANBH virus. These data suggest that AN6520 Ag is a normal cellular protein existing mainly in liver and that its quantity may vary under some conditions such as NANBH.  相似文献   
90.
Background contextSurgical treatment for spinal metastasis is still controversial. However, with the improvements in treatment for primary tumors, the survival rate of patients with spinal metastasis is enhanced. At the same time, surgical technique for spinal metastasis has also improved.PurposeThe purpose of this study was to examine trends in the surgical treatment for spinal metastasis and in-hospital patient outcomes on a national level.Study design/settingThis was an epidemiologic study using national administrative data from the Nationwide Inpatient Sample (NIS) database.Patient sampleAll discharges in the NIS with a diagnosis code of secondary malignant neoplasm of the spinal cord/brain, meninges, or bone who also underwent spinal surgery from 2000 to 2009 were included.Outcome measuresTrends in the surgical treatment for spinal metastasis, in-hospital complications and mortality, and resource use were analyzed.MethodsThe NIS was used to identify patients who underwent surgical treatment for spinal metastasis from 2000 to 2009, using the International Classification of Diseases, Ninth revision, Clinical Modification codes. Trends in the surgical treatment for spinal metastasis and in-hospital patient outcomes were analyzed.ResultsFrom 2000 to 2009, there was an increasing trend in the population growth–adjusted rate of surgical treatment for spinal metastasis (1.15–1.77 per 100,000; p<.001). Average Elixhauser comorbidity score increased over time (2.6–3.8; p<.001), and the overall in-hospital complication rate increased over time (14.8%–27.7%; p<.001), whereas in-hospital mortality rate and length of hospital stay remained stable over time (5.2%–4.6%, p=.413; 10.6–10.8 days, p=.626). Inflation-adjusted mean hospital charges increased more than two-fold over time ($50,390–$110,173; p<.001).ConclusionsDuring the last decade, surgical treatment for spinal metastasis has increased in the United States. The overall in-hospital complication rate and hospital charges increased, whereas the in-hospital mortality rate and length of hospital stay remained stable.  相似文献   
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