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101.
A study was conducted where the GPs in a district answered a questionnaire on reasons for hospital admission, divided into the categories: needed hospital investigation, hospital treatment, or needed care and nursing. They judged whether the admission could have been prevented. Finally, a multidisciplinary panel discussed ways to obtain better courses of admission. Of 266 admissions, 40 (15%) were due to a need for care and nursing. Ninety-seven (37%) of the admissions could be replaced by a short one-day stay, and 52 (20%) could have been postponed until the next day if that was possible. The panel discussion showed that municipalities can do more to strengthen the local professional support. It is concluded that the interface between primary care and the hospital should offer better opportunities for one-day admissions or sub-acute admissions, and that municipalities must be more aware of their responsibility for the care of fragile and ill people.  相似文献   
102.
Colonization of the nasopharynx by a middle ear pathogen is the first step in the development of otitis media in humans. The establishment of an animal model of nasopharyngeal colonization would therefore be of great utility in assessing the potential protective ability of candidate vaccine antigens (especially adhesins) against otitis media. A chinchilla nasopharyngeal colonization model for nontypeable Haemophilus influenzae (NTHI) was developed with antibiotic-resistant strains. This model does not require coinfection with a virus. There was no significant difference in the efficiency of NTHI colonization between adult (1- to 2-year-old) and young (2- to 3-month-old) animals. However, the incidence of middle ear infection following nasopharyngeal colonization was significantly higher in young animals (83 to 89%) than in adult chinchillas (10 to 30%). Chinchillas that had recovered either from a previous middle ear infection caused by NTHI or from an infection by intranasal inoculation with NTHI were completely protected against nasopharyngeal colonization with a homologous strain and were found to be the best positive controls in protection studies. Systemic immunization of chinchillas with inactivated whole-cell preparations significantly protected animals not only against homologous NTHI colonization but also partially against heterologous NTHI infection. In all protected animals, significant serum anti-P6 and anti-HMW antibody responses were observed. The outer membrane P6 and high-molecular-weight (HMW) proteins appear to be promising candidate vaccine antigens to prevent nasopharyngeal colonization and middle ear infection caused by NTHI.  相似文献   
103.
Aiming at finding out the ergonomics conditions of the nursing personnel in a hospital admission unit, the authors utilized as a methodological presupposition the search for a global experienced work situation through the analysis of some elements as: the man (nursing worker); the work activity (prescribed duty, real activities and work position) and the environment (temperature, noise and illumination). The authors selected the Cardiology admission unit for the site of their research. The results verified that the nursing workers the mentioned unit face problems related to salaries, work installations, relationship, work organization, levels of formation and the activities executed. The authors suggested some recommendations.  相似文献   
104.
105.
Iron deficiency anemia is associated with lower plasma thyroid hormone concentrations in rodents and, in some studies, in humans. The objective of this project was to determine if plasma triiodothyronine (T3) and thyroxine (T4) kinetics were affected by iron deficiency. Studies were done at a near-thermoneutral temperature (30 degrees C), and a cool environmental temperature (15 degrees C), to determine plasma T3 and T4 kinetics as a function of dietary iron intake and environmental need for the hormones. Weanling male Sprague-Dawley rats were fed either a low Fe diet [iron-deficient group (ID), <5 microg/g Fe] or a control diet [control group (CN), 35 microg/g Fe] at each temperature for 7 wk before the tracer kinetic studies. An additional ID group receiving exogenous thyroid hormone replacement was also used at the cooler temperature. For T4, the disposal rate was >60% lower (89 +/- 6 vs. 256 +/- 53 pmol/h, P < 0.001) in ID rats than in controls at 30 degrees C, and approximately 40% lower (192 +/- 27 vs. 372 +/- 26 pmol/h, P < 0.01) in ID rats at 15 degrees C. Exogenous T4 replacement in a cohort of ID rats at 15 degrees C normalized the T4 concentration and the disposal rate. For T3, the disposal rate was significantly lower in ID rats in a cool environment (92 +/- 11 vs. 129 +/- 11 pmol/h, P < 0.01); thyroxine replacement again normalized the T3 disposal rate (126 +/- 12 pmol/h). Neither liver nor brown fat thyroxine 5'-deiodinase activities were sufficiently different to explain the lower T3 disposal rates in iron deficiency. Thus, plasma thyroid hormone kinetics in iron deficiency anemia are corrected by simply providing more thyroxine. This suggests a central regulatory defect as the primary lesion and not peripheral alterations.  相似文献   
106.
Salmon calcitonin (sCT) is an example of one of the many bioactive peptides that require amidation of the carboxy terminus for full potency. We describe a method for the production of amidated sCT in the mammary gland of transgenic rabbits. Expression of a fusion protein comprising human alpha lactalbumin joined by an enterokinase cleavable linker to sCT was directed to the mammary gland under the control of the ovine beta lactoglobulin promoter. C-terminal amidation in vivo was achieved by extending the sCT by a single glycine residue that provides a substrate for endogenous amidating activity in the mammary gland. Full characterization of the released sCT demonstrated it to be equivalent to synthetic standard in terms of structure, purity, and potency.  相似文献   
107.
BACKGROUND: Oral contraceptives are prescribed as contraception but also as therapy for menstrual cycle disturbances and acne. We studied the prevalence of oral contraceptive (OC) use and the indications to start OC use among adolescents. METHODS: A cohort consisting of ninth grade secondary school girls (mean age 15.3+/-0.6 (s.d.) years) answered a questionnaire on their menstrual cycle. OC users were asked about duration and reasons for OC-use and the name of the preparation they used. The influence of calendar age, gynecological age and level of education on the prevalence of OC was studied by multiple logistic regression analysis. RESULTS: The response on the questionnaire was 92%. Of 2248 responders 248 (11%) used oral contraceptives: 74% used low dose 'sub 50' preparations, 3% pills with 50 microg estrogen, 3% tri-phase preparations and 17% pills with antiandrogens. Of girls aged 14, 15 and 16 years 4%, 12% and 28% respectively, used OC. Of the 15-year-olds 31% mentioned contraception as most important reason for OC use, 18% menstrual cycle irregularity, 26% dysmenorrhea, 10% acne and 5% other reasons. Calendar age, gynecological age and level of education were independent variables for OC use in general and for OC use for contraception or dysmenorrhea, but less so for OC use for menstrual cycle irregularity or acne. CONCLUSIONS: During adolescence low dose OC's were frequently used. In The Netherlands OC use among girls aged 15 and 16 years doubled in comparison with 1982. One third of the adolescent OC-users mentioned contraception as most important reason to start OC. Gynecological age (a determinant of biological maturation), calendar age (a determinant of biological maturation and lifestyle in peer groups), and level of education (a determinant of lifestyle in peer groups) were associated with OC use.  相似文献   
108.
The solution structure of an RNA-hairpin present in the pseudoknot, which is found at the 3'-terminus of turnip yellow mosaic virus genomic RNA, has been solved by nuclear magnetic resonance spectroscopy. The loop, which contains the sequence 5'-GGGUCA-3', was found to be highly structured and, contrary to expectations, does not attain its stability through GA or GC base pair formation but by triple interactions between the tilted adenosine and the minor groove sides of the first two guanosines. Interestingly, a very similar conformation was found for the cognate pseudoknot, implying that the 3'-hairpin is preformed for folding into a pseudoknotted structure. These findings suggest a mechanism of 'predetermined-fit' as a principle in RNA folding.  相似文献   
109.
110.
Staphylococcus aureus is an important pathogen of humans and other animals, causing bacteremia, abscesses, endocarditis, and other infectious syndromes. A signature-tagged mutagenesis (STM) system was adapted for use in studying the genes required for in vivo survival of S. aureus. An STM library was ultimately created in S. aureus RN6390, with Tn917 being used to create the transposon mutations. Pools of S. aureus RN6390 mutants were screened in mouse abscess, bacteremia, and wound infection models for growth attenuation after in vivo passage. One of the mutants that was identified displayed marked attenuation following large-pool screening in all three animal models, which was confirmed in bacteremia and endocarditis models of infection with a smaller pool of mutants. Sequence analysis of the entire open reading frame showed a 99% identity to the high-affinity proline permease (putP) gene characterized in another strain of S. aureus. In wound and murine abscess infection models, the putP mutant was approximately 10-fold more attenuated than was wild-type strain RN6390. Another S. aureus strain transduced with the putP mutation also displayed an attenuated phenotype after passage in the wound model. A [3H]proline uptake assay showed that less proline was specifically transported into the putP mutant than into strain RN6390. The reduced viability of the bacteria possessing the mutation in the S. aureus high-affinity proline permease suggests that proline scavenging by the bacteria is important for in vivo growth and proliferation and that analogs of proline may serve as potential antistaphylococcal therapeutic agents.  相似文献   
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