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1.
The molecular evolution of mammalian Y-linked DNA sequences is of special interest because of their unique mode of inheritance: most Y- linked sequences are clonally inherited from father to son. Here we investigate the use of Y-linked sequences for phylogenetic inference. We describe a comparative analysis of a 515-bp region from the male sex- determining locus, Sry, in 22 murine rodents (subfamily Murinae, family Muridae), including representatives from nine species of Mus, and from two additional murine genera--Mastomys and Hylomyscus. Percent sequence divergence was < 0.01% for comparisons between populations within a species and was 0.19%-8.16% for comparisons between species. Our phylogenetic analysis of 12 murine taxa resulted in a single most- parsimonius tree that is highly concordant with phylogenies based on mitochondrial DNA and allozymes. A total evidence tree based on the combined data from Sry, mitochondrial DNA, and allozymes supports (1) the monophyly of the subgenus Mus, (2) its division into a Palearctic group (M. musculus, M. domesticus, M. spicilegus, M. Macedonicus, and M. spretus) and an Oriental group (M. cookii++, M. cervicolor, and M. caroli), and (3) sister-group relationships between M. spicilegus and M. macedonicus and between M. cookii and M. cervicolor. We argue that Y- chromosome DNA sequences represent a valuable new source of characters for phylogenetic inference.   相似文献   
2.
The effect of carbon dioxide concentration on the bacterial leaching of a pyrite-arsenopyrite ore concentrate was studied in continuous-flow reactors. Steady-state operation with two feed slurry densities, 6 wt% and 16 wt% solids, were tested for the effect of carbon dioxide concentration. Bacterial growth rates were estimated via the measurement of carbon dioxide consumption rates. Aqueous-phase carbon dioxide concentrations in excess of 10 mg/L were found to be inhibitory to bacterial growth. (c) 1993 John Wiley & Sons, Inc.  相似文献   
3.
Several lines of experimental evidence are presented suggesting that the L antigens in low potassium (LK) sheep red cells are associated with separate Na(+)K(+) pump flux is distinct from the action of anti-L(l) on K(+) leak flux, implying that K(+) leak transport sites may not be converted into active pumps by the L antiserum. Treatment of LK red cells with trypsin completely abolished both the stimulation of K(+) pump flux and the enhancement of the rate of ouabain binding brought about by anti- L. That this effect is due to a total destruction of the L(p) determinant associated with the LK pump was evident from the complete failure of anti-L(p) to bind to trypsinized LK red cells. The L(p) antigen can be effectively protected against the trypsin attack by prior incubation with anti-L, indicating that the sites for antibody binding and trypsin action may be closely adjacent at the structural level. Trypsin treatment, however, did not interfere with anti-L(l) reducing ouabain insensitive K(+) leak influx, nor did it prevent binding of anti-L(ly), the hemolytically active L antibody which is probably identical with anti-L(l). The functional independence of the L(p) and L(l) sites was documented by the observation that anti-L(l) still reduced K(+) leak influx in LK cells with experimentally induced high potassium concentrations, at which K(+) pump flux is fully suppressed, whether or not anti-L(p) was binding to the L(p) antigen associated with the LK pump.  相似文献   
4.
The effects of cage fish farming on physico-chemical and bacteriological water quality in Lake Volta, Ghana, were investigated in 2013–2014. Farmed and unfarmed (control) areas of the lake were selected for monitoring. Nutrients, temperature, dissolved oxygen, conductivity, turbidity, pH, total coliforms, Pseudomonas and Vibrio spp. in the water were monitored monthly. Analyses of the water samples were carried out according to standard procedures. Physico-chemical quality of the water in both farm and control sites were within ranges typical of minimally impacted water and did not vary significantly between the two contrasting sites. The bacteriological analysis, however, revealed contamination of the lake water by fish farming. The bacterial counts at the farmed sites were significantly higher (p < 0.05) than those of the control sites, with figures at the farmed sites ranging from 132 to 1 708 cfu 100 ml?1 for total coliforms, 514 to 5 170 cfu 100 ml?1 Pseudomonas spp. and 14 to 516 cfu 100 ml?1 for Vibrio spp. The results suggested that cage fish farming has increased bacterial loads in the lake water, but has had minimal impact on its physico-chemical quality.  相似文献   
5.
BACKGROUND: Infiltrating syringomatous adenoma is a rare tumor of the breast that can radiologically mimic invasive duct carcinoma. Detailed fine needle aspiration cytology and needle core biopsy findings on this lesion have not been previously described. CASE: The clinical, radiologic and pathologic findings of an infiltrating syringomatous adenoma of the breast in a 71-year-old female who presented with a subareolar lump are described. The cytology of the tumor was characterized by a combination of a background of plump, fibroblastoid cells and cohesive sheets of bland epithelial cells. Histologically the tumor showed infiltrating, duct-like structures with squamous metaplasia and a desmoplastic stroma. CONCLUSION: Fine needle aspiration cytology and needle core biopsy can distinguish infiltrating syringomatous adenoma from malignant disease of the breast.  相似文献   
6.

Introduction  

Frequent assessments of rheumatoid arthritis (RA) disease activity allow timely adaptation of therapy, which is essential in preventing disease progression. However, values of acute phase reactants (APRs) are needed to calculate current composite activity indices, such as the Disease Activity Score (DAS)28, the DAS28-CRP (i.e. the DAS28 using C-reactive protein instead of erythrocyte sedimentation rate) and the Simplified Disease Activity Index (SDAI). We hypothesized that APRs make limited contribution to the SDAI, and that an SDAI-modification eliminating APRs – termed the Clinical Disease Activity Index (CDAI; i.e. the sum of tender and swollen joint counts [28 joints] and patient and physician global assessments [in cm]) – would have comparable validity in clinical cohorts.  相似文献   
7.
A Comparison of Two Recorders for Obtaining In-flight Heart Rate Data   总被引:1,自引:0,他引:1  
Measurement of mental workload has been widely used for evaluation of aircraft design, mission analysis and assessment of pilot performance during flight operations. Heart rate is the psychophysiological measure that has been most frequently used for this purpose. The risk of interference with flight safety and pilot performance, as well as the generally constrained access to flights, make it difficult for researchers to collect in-flight heart rate data. Thus, this study was carried out to investigate whether small, non-intrusive sports recorders can be used for in-flight data collection for research purposes. Data was collected from real and simulated flights with student pilots using the Polar Team System sports recorder and the Vitaport II, a clinical and research recording device. Comparison of the data shows that in-flight heart rate data from the smaller and less intrusive sports recorder have a correlation of.981 with that from the clinical recorder, thus indicating that the sports recorder is reliable and cost-effective for obtaining heart rate data for many research situations.  相似文献   
8.
There is increasing evidence for beneficial effects of early DMARD (disease-modifying antirheumatic drug) therapy over delayed treatment in patients who present with arthritis of recent onset. However, no universal consensus exists concerning the choice of initial drug or whether single drugs or combinations should be given as initial treatments. Recent studies have focused on the benefits of various strategies in which treatments were tailored to achieve low levels of disease activity, as assessed using validated response criteria. These studies demonstrated superiority of 'aggressive' over 'conventional' approaches. Whether the inclusion of tumour necrosis factor antagonists or other biologic targeted therapies in such strategies confers additional benefits in terms of improved long-term outcomes must be clarified by further studies. Assessment of risks in the individual patient, allowing individual 'tailoring' of the initial treatment, would be desirable.  相似文献   
9.
The use of immunohistochemistry (IHC) in staging bone marrow in non-Hodgkin''s lymphoma (NHL) is largely limited to ambiguous cases, particularly those with lymphoid aggregates. Its role in routine clinical practice remains unestablished. This study aimed to determine whether the routine use of IHC in diffuse large B-cell lymphoma (DLBCL) would improve the detection of lymphomatous involvement in the bone marrow. It also sought to determine the impact of IHC on predicting survival compared with routine histological diagnosis using hematoxylin and eosin (H&E), Giemsa, and reticulin staining. The bone marrow trephines of 156 histologically proven DLBCL cases were assessed on routine histology, and IHC using two T-cell markers (CD45RO and CD3), two B-cell markers (CD20 and CD79a), and κ and λ light chains. IHC detected lymphomatous involvement on an additional 11% cases compared with histology alone. Although both routine histology and IHC were good predictors of survival, IHC was better at predicting survival on stepwise multivariate Cox regression analysis. IHC performed routinely on bone marrow trephines has the ability to improve detection of occult lymphoma in experienced hands. Furthermore, it is a better predictor of survival compared with routine histological examination alone. (J Histochem Cytochem 56:893–900, 2008)  相似文献   
10.

Objective

Curative surgery is not an option for many patients with clinical stage I non-small-cell lung carcinoma (NSCLC), but radical radiosurgery may be effective.

Methods

Inoperable patients with small peripheral clinical stage I NSCLC were enrolled in this study. Three-to-five fiducial markers were implanted in or near tumors under CT guidance. Gross tumor volumes (GTVs) were contoured using lung windows. The GTV margin was expanded by 5 mm to establish the planning treatment volume (PTV). A dose of 42–60 Gy was delivered to the PTV in 3 equal fractions in less than 2 weeks using the CyberKnife radiosurgery system. The 30-Gy isodose contour extended at least 1 cm from the GTV. Physical examination, CT imaging and pulmonary function testing were completed at 6 months intervals for three years following treatment.

Results

Twenty patients with an average maximum tumor diameter of 2.2 cm (range, 1.1 – 3.5 cm) and a mean FEV1 of 1.08 liters (range, 0.53 – 1.71 L) were treated. Pneumothorax requiring tube thoracostomy occurred following CT-guided fiducial placement in 25% of the patients. All patients completed treatment with few acute side effects and no procedure-related mortality. Transient chest wall discomfort developed in 8 of the 12 patients with lesions within 5 mm of the pleura. The mean percentage of the total lung volume receiving a minimum of 15 Gy was 7.3% (range, 2.4% to 11.3%). One patient who received concurrent gefitinib developed short-lived, grade III radiation pneumonitis. The mean percent predicted DLCO decreased by 9% and 11% at 6 and 12 months, respectively. There were no local failures, regional lymph node recurrences or distant metastases. With a median follow-up of 25 months for the surviving patients, Kaplan-Meier overall survival estimate at 2 years was 87%, with deaths due to COPD progression.

Conclusion

Radical CyberKnife radiosurgery is a well-tolerated treatment option for inoperable patients with small, peripheral stage I NSCLC. Effective doses and adequate margins are likely to have contributed to the optimal early local control seen in this study.  相似文献   
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