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61.
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The plant viruses alfalfa mosaic virus (AMV) and brome mosaic virus (BMV) each divide their genetic information among three RNAs while tobacco mosaic virus (TMV) contains a single genomic RNA. Amino acid sequence comparisons suggest that the single proteins encoded by AMV RNA 1 and BMV RNA 1 and by AMV RNA 2 and BMV RNA 2 are related to the NH2-terminal two-thirds and the COOH-terminal one-third, respectively, of the largest protein encoded by TMV. Separating these two domains in the TMV RNA sequence is an amber termination codon, whose partial suppression allows translation of the downstream domain. Many of the residues that the TMV read-through domain and the segmented plant viruses have in common are also conserved in a read-through domain found in the nonstructural polyprotein of the animal alphaviruses Sindbis and Middelburg. We suggest that, despite substantial differences in gene organization and expression, all of these viruses use related proteins for common functions in RNA replication. Reassortment of functional modules of coding and regulatory sequence from preexisting viral or cellular sources, perhaps via RNA recombination, may be an important mechanism in RNA virus evolution.  相似文献   
64.
Staphylococcus epidermidis RP62A (ATCC 35984) was grown in tryptic soy broth (TSB), iron-depleted TSB (TSB-Fe), iron-reconstituted TSB-Fe (TSB+Fe), a chemically defined medium, and fetal calf serum (FCS) and on silastic disks in chambers that were sutured to the pig peritoneal wall. Bacterial cell wall proteins were extracted by digestion with recombinant lysostaphin, separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and detected by silver staining. Cell wall proteins from TSB-, chemically defined medium-, or FCS-grown cells had a complex profile of greater than 25 protein bands spanning the full molecular mass range. By contrast, a digest obtained from in vivo-grown cells had only five major proteins of 40 kDa or greater. Proteins of 130 and 106 kDa were present in the cell envelopes of TSB-Fe- and in vivo-grown cells but not in those grown in TSB or TSB+Fe. A 43-kDa protein expressed by in vitro-grown cells and 52- and 96-kDa proteins expressed by in vivo-grown cells reacted with antisera from pigs with the chamber implants and from catheterized, paracatheter-inoculated pigs but not with hyperimmune sera from pigs immunized with TSB-grown cells. The data indicate that S. epidermidis, growing under in vivo conditions, expresses antigens distinct from those that are grown in vitro.  相似文献   
65.

Purpose

The purpose of this study is to evaluate the efficacy and safety of the medical method in the management of first trimester spontaneous onset incomplete abortion, by using misoprostol vaginal tablets, in comparison to surgical evacuation, with an intention of completing the procedure within 24 h.

Methods

In this prospective, randomised study of 100 women admitted with features suggestive of incomplete abortion, 50 women received misoprostol vaginal tablets, while another 50 underwent suction curettage of products of conceptus. They were followed up after 24 h of last dosage of misoprostol or surgical intervention. Statistical analysis was done with respect to efficacy, safety and procedure-related side effects.

Results

In this study, when analysed after 24 h of treatment allocation, the efficacy of misoprostol was 91.3 %, and the efficacy of the surgical method was 96 %, with the statistical difference being insignificant. Procedure-related blood loss and pain perception between the two groups were statistically insignificant. However, the incidence of fever in the misoprostol group statistically appeared higher.

Conclusions

Misoprostol could be a safe and easily accessible alternative to surgical evacuation, in cases of first trimester spontaneous onset incomplete miscarriage, and could be administered by the patient herself at home.  相似文献   
66.
67.

Objectives

Accelerometer placement at the wrist is convenient and increasingly adopted despite less accurate physical activity (PA) measurement than with waist placement. Capitalizing on a study that started with wrist placement and shifted to waist placement, we compared associations between PA measures derived from different accelerometer locations with a responsive arterial health indicator, carotid-femoral pulse wave velocity (cfPWV).

Design

Cross-sectional study.

Methods

We previously demonstrated an inverse association between waist-worn pedometer-assessed step counts (Yamax SW-200, 7 days) and cfPWV (?0.20 m/s, 95% CI ?0.28, ?0.12 per 1000 step/day increment) in 366 adults. Participants concurrently wore accelerometers (ActiGraph GT3X+), most at the waist but the first 46 at the wrist. We matched this subgroup with participants from the ‘waist accelerometer’ group (sex, age, and pedometer-assessed steps/day) and assessed associations with cfPWV (applanation tonometry, Sphygmocor) separately in each subgroup through linear regression models.

Results

Compared to the waist group, wrist group participants had higher step counts (mean difference 3980 steps/day; 95% CI 2517, 5443), energy expenditure (967 kcal/day, 95% CI 755, 1179), and moderate-to-vigorous-PA (138 min; 95% CI 114, 162). Accelerometer-assessed step counts (waist) suggested an association with cfPWV (?0.28 m/s, 95% CI ?0.58, 0.01); but no relationship was apparent with wrist-assessed steps (0.02 m/s, 95% CI ?0.24, 0.27).

Conclusions

Waist but not wrist ActiGraph PA measures signal associations between PA and cfPWV. We urge researchers to consider the importance of wear location choice on relationships with health indicators.  相似文献   
68.
Alcohol-related liver disease (ALD) is a common indication for orthotopic liver transplantation (OLT) in adults. Although return to 'heavy drinking' post-OLT is believed to be uncommon, the prevalence and severity of alcohol-related liver injury in such patients is not well characterized. We retrospectively reviewed the records of 68 adult patients who underwent OLT for ALD to determine the incidence of return to heavy drinking and to assess their clinical outcome. Follow-up ranged from 8-99 months (mean 42) post-OLT; 54 patients were followed for > or = 12 months. Ten patients (15%) had evidence of coexisting viral hepatitis (hepatitis C in 9 and hepatitis B in 1) before OLT. Six of 68 patients (8%) returned to heavy drinking post-OLT, and three of those died of alcoholic hepatitis at nine months, 2.5 and 3.5 years after OLT. In two of these three patients, premortem liver biopsy showed histologic features of alcoholic hepatitis in addition to bridging fibrosis or cirrhosis. None of the three patients who died of ALD had coexisting viral hepatitis. Of the 57 patients surviving for > or = 3 months post-OLT, 4 of 8 patients (50%) with steatosis and Mallory bodies in their native livers returned to heavy drinking compared to only 2/49 (4%) without these histologic findings (P<0.05). In conclusion, the incidence of heavy drinking post-OLT was uncommon, however, it was associated with fatal alcoholic hepatitis in 50% of patients. Rapidly progressive alcohol-related liver injury was seen even in the absence of coexisting viral hepatitis. The presence of steatosis and Mallory bodies in the native liver, which suggests recent or ongoing alcohol-related liver injury, predicted a return to heavy drinking post-OLT.  相似文献   
69.
Photochemical interconversion between the red-absorbing (Pr) and the far-red-absorbing (Pfr) forms of the photosensory protein phytochrome initiates signal transduction in bacteria and higher plants. The Pr-to-Pfr transition commences with a rapid Z-to-E photoisomerization at the C15C16 methine bridge of the bilin prosthetic group. Here, we use femtosecond stimulated Raman spectroscopy to probe the structural changes of the phycocyanobilin chromophore within phytochrome Cph1 on the ultrafast time scale. The enhanced intensity of the C15–H hydrogen out-of-plane (HOOP) mode, together with the appearance of red-shifted CC stretch and NH in-plane rocking modes within 500 fs, reveal that initial distortion of the C15C16 bond occurs in the electronically excited I* intermediate. From I*, 85% of the excited population relaxes back to Pr in 3 ps, whereas the rest goes on to the Lumi-R photoproduct consistent with the 15% photochemical quantum yield. The C15–H HOOP and skeletal modes evolve to a Lumi-R-like pattern after 3 ps, thereby indicating that the C15C16 Z-to-E isomerization occurs on the excited-state surface.  相似文献   
70.
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