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991.
992.
The complete nucleotide sequence of the gene encoding the Corynebacterium glutamicum mannose enzyme II (EIIMan) was determined. The gene consisted of 2052 base pairs encoding a protein of 683 amino acid residues; the molecular mass of the protein subunit was calculated to be 72570 Da. The N-terminal hydrophilic domain of EIIMan showed 39.7% homology with a C-terminal hydrophilic domain of Escherichia coli glucose-specific enzyme II (EIIGlc). Similar homology was shown between the C-terminal sequence of EIIMan and the E. coli glucose-specific enzyme III (EIIIGlc), or the EIII-like domain of Streptococcus mutans sucrose-specific enzyme II. Sequence comparison with other EIIs showed that EIIMan contained residues His-602 and Cys-28 which were homologous to the potential phosphorylation sites of EIIIGlc, or EIII-like domains, and hydrophilic domains (IIB) of several EIIs, respectively.  相似文献   
993.
994.
Microalbuminuria is thought to be rare in people with insulin-dependent diabetes mellitus (IDDM) for less than 5 years. We measured its prevalence in 733 clinic-attending IDDM patients with diabetes duration of 1-5 years in two large multicenter studies [EURODIAB IDDM Complications Study and the World Health Organization (WHO) Multinational Study]. We also compared characteristics of microalbuminuric patients with IDDM for 1-5 years versus more than 5 years' duration. Albumin excretion rate was measured from a timed 24-h urine collection in the EURODIAB Study. Proteinuria was measured by the salicylsulphonic acid test in the WHO Study. The prevalence of microalbuminuria (20-200 micrograms/min, EURODIAB) was 18% [95% confidence interval (CI) 13%-22%)]. The prevalence of light proteinuria was 15% (9%-20%, WHO study). Raised protein excretion was a consistent finding in 34 of the 36 centers. The increased cardiovascular risk (raised blood pressure and total cholesterol) associated with microalbuminuria in patients with IDDM for more than 5 years was also apparent in those with diabetes for 1-5 years. However, repeat urine testing suggested that microalbuminuria before 5 years was more likely to be transient or reversible. In conclusion, these two studies in 36 centers, which used different methods more than 10 years apart, show consistently that raised urinary albumin excretion occurs before 5 years of IDDM. The clinical significance of this needs to be examined by prospective observation.  相似文献   
995.
We report responses from 559 clients of female prostitutes, with a view to determining to what extent previously identified factors play a part in condom use. To increase the response rate to advertisements in daily and weekly newspapers, interviews were held by phone. This procedure had the advantage of ensuring the anonymity many clients demanded. Of those clients having vaginal or anal contact (91%), 14% had not always used condoms in the previous year. Compared with consistent condom users, these men were less highly educated, had twice as many commercial contacts, and had more contacts with "steady" prostitutes. They were either more emotionally motivated to visit prostitutes than were consistent condom users or exhibited a stronger need for sexual variation. They showed a more compulsive attitude toward visiting prostitutes, had a more negative attitude toward prostitution in general, evaluated condoms more negatively, had a higher personal efficacy to achieve unsafe contacts, and had a higher general risk assessment, commensurate with their behavior. Men with only safe contacts had either an intrinsic or an extrinsic motivation for condom use. Among extrinsically motivated men, their behavior change was more recent and had not yet taken root: They still envisioned unsafe commercial sex to be possible in the future. Education aimed at the small group of men practicing unsafe contacts will not easily and directly lead to behavior change. But these educational activities may support prostitutes to persist in (consistent) condom use, regardless of clients' pressure to do otherwise.  相似文献   
996.
The association of water with the Mn of the water oxidizing complex was investigated using H2(17)O- and 2H2O-reconstituted lyophilized photosystem II particles. The pulsed electron paramagnetic resonance (EPR) technique of electron spin echo envelope modulation (ESEEM) was used to investigate the interaction of the magnetic 2H and 17O nuclei with the paramagnetic S2 state of the Mn complex and other photosystem II components. ESEEM offers a much more specific and sensitive detection of this type of interaction than continuous wave (CW) EPR. Unlike earlier reports using CW EPR, these experiments did not detect any interaction of water with the multiline EPR signal from the S2 state of the Mn complex. No signals indicating specific interaction of either H or O with the multiline signal were detected. Signals due to 2H and 17O were detected only at the Larmour frequency, indicating nonspecific "distant ENDOR" effects. A weak interaction with 17O was detected both in S1, when the Mn is EPR silent, and in S2, but only on the high-field side of g = 2. This interaction may be with the Rieske iron-sulfur center in the cytochrome b6f complex. The results were the same whether the multiline signal was generated by 200 K illumination of dark-frozen samples, or by room temperature illumination in the presence of the inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). Illumination at room temperature in the presence of an electron acceptor to allow multiple turnovers of the system with cycling of the S states did not result in the appearance of any new interactions. These results appear to exclude close (less than 6 A) binding of water to the Mn center giving rise to the multiline signal, and also to exclude mechanisms in which water oxidation involves the breaking and re-formation of the mu-oxo bridges of the Mn complex. They cannot, however, exclude models in which water binding to the manganese complex and direct oxidation by the manganese complex occur in the higher S states, or are catalyzed by one bis(mu-oxo) Mn dimer while oxidizing equivalents are accumulated in the S2 state by a second bis(mu-oxo) Mn dimer.  相似文献   
997.
This article presents health expectancy calculations from Bulgaria for 1976-1992. The calculations are based on mortality statistics and data from a national information system from the Expert Medical Commissions on Working Capacity about loss of working capacity. Following internationally accepted terminology, the most appropriate term for the health expectancies presented here is "occupational handicap-free life expectancy' (OHFLE). Life expectancies were calculated as partial life expectancies from ages 16 to 59. Health expectancy calculations followed Sullivan's cross-sectional method with age and sex specific prevalence data on occupational handicap. Around 1985 a three- to four-fold increase in these prevalences occurred. The distribution of occupational handicaps over sexes, age groups and severity levels, however, remained fairly constant. The results show a decrease both in partial life expectancy within the age range 16-59 and in OHFLE at the age of 16 for men. For women a more or less stable partial life expectancy and a decrease in OHFLE at the age of 16 was found around 1985. The introduction of more incentives for people who successfully registered probably caused the decrease around 1985. Major social changes may have acted as confounding factors for the fluctuations after 1985. On the other hand the findings may reflect real changes in population health due to an increasing incidence in some major disease categories. The nation-wide system for assessment and registration of health related working incapacity has proved a useful source for an attempt to calculate OHFLE. Given uncertainties about the population health underlying these changes in OHFLE, however, it is recommended that health interview and health examination surveys should be considered as alternative routes for achieving a more comprehensive picture of population health in Bulgaria.  相似文献   
998.
PURPOSE: Percutaneous renal access can be challenging, particularly when the collecting system is not distended. Precise entry into a selected calyx facilitates subsequent percutaneous manipulations, but this skill requires extensive experience. In an attempt to improve accuracy while decreasing technical challenges, we developed a robotic system that automates the task of fluoroscopic image-guided percutaneous needle placement. MATERIALS AND METHODS: The prototype system consisted of a three degree-of-freedom robot with a needle injector end-effector. Imaging was provided by a biplanar fluoroscope. After correction of image distortion and fluoroscope calibration, robot to image-space registration was completed. To validate the system's ability to insert a needle into a calyx, ex vivo porcine kidneys suspended in agarose gel and distended with iodinated contrast solution were used as a model. In situ renal access tests with three 20 kg. pigs were performed. Access was confirmed by passing a flexible wire or aspirating iodinated contrast from the collecting system. RESULTS: The diameter of target calyces ranged from 3 to 7 mm. The in vitro accuracy of final needle tip positioning was 0.43 mm. In the ex vivo model, successful "one stick" access occurred on 10 of 12 attempts (83%). In situ access on the first attempt was successful for 6 of 12 target calyces (50%). Needle or tissue deflection accounted for each failure. CONCLUSION: The feasibility of a robotic system to assist in the percutaneous access of small and delicate renal calyces has been demonstrated. Additional work in reducing procedural steps and correcting for tissue deflection during needle passage is necessary to improve accuracy and to allow for clinical application.  相似文献   
999.
Two new areas of anchor development are biodegradable anchors and "mini" anchors. The group of biodegradable anchors tested include the Bio-Anchor, LactoSorb, Biofix, Bio-Statak, Mini Screw suture anchor, DePuy 4.5 molded, DePuy 4.5 machined, DePuy 3.5 machined, TAG Wedge 4, TAG Rod 2, TAG Wedge 3, TAG Wedge 2, and Stealth. "Mini anchors" have drill holes or minor diameters of < 2.2 mm. Those tested include the Mini Revo and Bio-Anchor, miniHarpoon, mini Mitek and Fast in 3, Statak 1.5 and 2.5, SB 2 and PeBA 3, Corkscrew 5, Corkscrew 3.5, and Fastak A2, Ogden 2.5, TAG Wedge 2, ROC 1.9, and Questus 2.5. Additional anchors tested that fit neither category include the Anspach, Questus 3.5 and 5.0, SB 3 and PeBA-C, Ogden 3.5, Fast in 4, Ultrafix, and the ROC 3.5, ROC 2.8, ROC 2.3, and ROC XS. An anchor comparison, using an established protocol in fresh porcine femurs, recorded failure strength, failure mode, eyelet size, minor and major diameters, and drill hole sizes. Except for the Bio-Anchor and TAG Wedge 2, biodegradable anchors tend to be larger to compensate for their lower strength relative to metal. Biodegradable screw anchors' predominant failure mode was eyelet cutout, whereas biodegradable nonscrew anchors failed to predominantly by anchor pullout. From an initial mechanical perspective, these biodegradable anchors perform acceptably. Both biodegradable and "mini" anchors include screw and nonscrew designs. As expected, screw designs perform well and generally fail at higher loads than nonscrew anchors. Although biodegradable anchors, as a group, are not as strong as metal anchors, they are stronger than the sutures for which they are designed. The move to smaller ("mini") and biodegradable anchors is supported by these data. Whether an anchor fails at twice the suture breaking strength or 10 times the suture breaking strength should make no difference.  相似文献   
1000.
BACKGROUND: A national survey of tuberculosis notifications in England and Wales was carried out in 1993 to determine the notification rate of tuberculosis and the trends in the occurrence of disease by ethnic group in comparison with the findings of similar surveys in 1978/79, 1983, and 1988. The prevalence of HIV infection in adults notified with tuberculosis in the survey period was also estimated. METHODS: Clinical, bacteriological, and sociodemographic information was obtained on all newly notified cases of tuberculosis in England and Wales during the six months from 2 January to 2 July 1993. The prevalence of HIV infection in 16-54 year old patients with tuberculosis notified throughout 1993 was assessed using "unlinked anonymous" testing supplemented by matching of the register of patients with tuberculosis with that of patients with AIDS reported to the PHLS AIDS centre. Annual notification rates were calculated using population estimates from the 1993 Labour Force Survey. RESULTS: A total of 2706 newly notified patients was eligible for inclusion in the survey of whom 2458 were previously untreated the comparable figures for 1988 were 2408 and 2163. The number of patients of white ethnic origin decreased from 1142 (53%) in 1988 to 1088 (44%) in 1993 whereas those of patients of Indian, Pakistani, or Bangladeshi (Indian subcontinent (ISC)) ethnic origin increased from 843 (39%) in 1988 to 1014 (41%) and those of "other" (non-white, non-ISC) ethnic origins increased from 178 (8%) to 356 (14%). The largest increase was seen in the black African ethnic group from 37 in 1988 to 171 in 1993. Forty nine per cent of patients had been born abroad and the highest rates were seen in those who had recently arrived in this country. The overall annual notification rate for previously untreated tuberculosis in England and Wales increased between 1988 and 1993 from 8.4 to 9.2 per 100,000 population. The rate declined in the white, Indian, and black Caribbean ethnic groups and increased in all other groups. In the white group the rate of decline has slowed since the last survey: in several age groups the rates were higher in 1993 than 1988 but the numbers in these groups were small. Thirty six (4.1%) of the 882 previously untreated respiratory cases were resistant to isoniazid and three (0.3%) to isoniazid and rifampicin. Sixty two (2.3%) adults aged 16-54 years were estimated to be HIV-infected. Evidence of under-reporting of HIV positive tuberculosis patients was found. CONCLUSIONS: The number of cases and annual notification rate for previously untreated tuberculosis increased between 1988 and 1993. Although the decline in rates in the white population has continued, the rate of decline has slowed. The high rates in the ISC ethnic group population have continued to decline since 1988 whereas rates in the black African group have increased. An increased proportion of cases were found among people born abroad, particularly those recently arrived in this country. In previously untreated cases the level of drug resistance remains low and multi-drug resistance is rare. A small proportion of adults with tuberculosis were infected with HIV but there may be selective undernotification of tuberculosis in these patients.  相似文献   
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