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91.
The amino acid sequence of the NH2-terminal 34 residues of human parathyroid hormone (PTH) has been determined and duplicated synthetically to produce a peptide that is biologically active. In the amino acid sequences of the bovine and porcine hormones, the glutamic acid function at position 22 has been revised to glutamine. Among these initial 34 residues, human PTH differs from bovine PTH by 5 residues and from porcine PTH by 4 residues. Native human PTH and the synthetic human PTH (1–34) peptide are not rigid structures, and significant changes in conformation were observed during pH titration. In addition, at physiologic pH, native human PTH appeared to differ in structure from human PTH (1–34) in the region of the tryptophan residue (residue 23). The fluorescence spectrum of human PTH revealed a maximum at 344 nm, but the spectrum of human PTH (1–34) had a peak at 343 nm; the spectrum of human PTH (1–34) was normalized to 346 nm in 6 M guanidine hydrochloride, but there was no shift with the intact hormone. Fluorescence titration of human PTH in the alkaline region revealed no loss of tryptophanyl fluorescence in aqueous solution or in 6 M guanidine hydrochloride. The synthetic human PTH (1–34) peptide, however, showed an approximately 25 per cent loss of indole fluorescence during alkaline titration which could be normalized with denaturing reagents. These studies suggest that synthetic fragments of the native hormone may not have the same tertiary conformation as the same sequence in the intact hormone. These findings may be of major significance with regard to the biologic activity and immunologic cross reactivity of synthetic fragments and the native hormone.  相似文献   
92.
To assess the feasibility and safety of coronary angiography combined, where necessary, with ad hoc angioplasty in an outpatient setting; a prospective, single-center study. The first 172 patients (154 men, 59 +/- 11 years) considered at low risk for complications were enrolled for outpatient-coronary angiography with or without angioplasty via a radial approach. The inclusion criteria were clinical, not based on angiography. After angiography/angioplasty, creatinine and troponin were assayed (outside the hospital) within 24h and patients were telephoned and asked about their clinical condition. Angioplasty was performed in 69 (40%) patients and 130 patients (75.6%) were discharged on the same day. In the angioplasty group, a history of coronary dilatation was more common in patients discharged on the same day (p = 0.05), whereas bifurcation lesions were more frequent in subjects who were kept in hospital (p < 0.0001). No serious complications occurred during the study. Of the 42/172 prolonged hospitalizations, eight were due to minor procedural complications, five due to failure of the radial route and three for indications for bypass surgery; the others were kept in for reasons unrelated to a complication (e.g., the examination was performed late in the day, a particularly complex procedure, etc.). Four (3%) of the 24-hour telephone calls led to a visit, but not hospital admission. Overall, performing angiography and "ad hoc" angioplasty in the course of a single outpatient visit makes it possible to foreshorten the hospital stay and increase patient throughput with a given hospital capacity and, this, without increasing clinical risk. Exactly how these patients are selected remains to be defined and may certainly be improved compared to this initial experiment. An outpatient-coronary angiography and ad hoc angioplasty strategy is a viable option with a low risk for patients selected on the basis of simple clinical criteria. It combines the advantages of increased convenience for the patient and lower costs.  相似文献   
93.
94.
Endo-rectal repair of rectocele   总被引:6,自引:2,他引:6  
Rectocele may cause colorectal symptoms particularly difficulty in evacuation. It is readily identified on clinical examination of the perineum but the pathophysiological abnormality can easily be defined by defaecography. Between 1984 and 1988 we have operated on 16 patients who presented with difficulty in evacuation associated with rectocele. We have used a simple endo-anal repair aimed to restore a firm recto-vaginal septum. Excellent functional results were obtained in 11 patients, 4 were considerably improved and one patient had a poor result.  相似文献   
95.
96.
Candida guilliermondii (teleomorph Meyerozyma guilliermondii) is an ascomycetous species belonging to the Saccharomycotina CTG clade which has been studied over the last 40 years due to its biotechnological interest, biological control potential and clinical importance. Such a wide range of applications in various areas of fundamental and applied scientific research has progressively made C. guilliermondii an attractive model for exploring the potential of yeast metabolic engineering as well as for elucidating new molecular events supporting pathogenicity and antifungal resistance. All these research fields now take advantage of the establishment of a useful molecular toolbox specifically dedicated to C. guilliermondii genetics including the construction of recipient strains, the development of selectable markers and reporter genes and optimization of transformation protocols. This area of study is further supported by the availability of the complete genome sequence of the reference strain ATCC 6260 and the creation of numerous databases dedicated to gene ontology annotation (metabolic pathways, virulence, and morphogenesis). These genetic tools and genomic resources represent essential prerequisites for further successful development of C. guilliermondii research in medical mycology and in biological control by facilitating the identification of the multiple factors that contribute to its pathogenic potential. These genetic and genomic advances should also expedite future practical uses of C. guilliermondii strains of biotechnological interest by opening a window into a better understanding of the biosynthetic pathways of valuable metabolites.  相似文献   
97.
We studied the impact of sleep deprivation on action monitoring. Each participant performed a Simon task after a normal night of sleep and after 26 h of awakening. Reaction time (RT) distributions were analyzed and the sensitivity of the error negativity (Ne/Ne like) to response correctness was examined.  相似文献   
98.
99.
European Journal of Clinical Microbiology & Infectious Diseases - During an epidemic period, we compared patients hospitalized for initial suspicion of COVID-19 but for whom an alternative...  相似文献   
100.
Background

SARS-CoV-2 infection leads to high viral loads in the upper respiratory tract that may be determinant in virus dissemination. The extent of intranasal antiviral response in relation to symptoms is unknown. Understanding how local innate responses control virus is key in the development of therapeutic approaches.

Methods

SARS-CoV-2-infected patients were enrolled in an observational study conducted at the Geneva University Hospitals, Switzerland, investigating virological and immunological characteristics. Nasal wash and serum specimens from a subset of patients were collected to measure viral load, IgA specific for the S1 domain of the spike protein, and a cytokine panel at different time points after infection; cytokine levels were analyzed in relation to symptoms.

Results

Samples from 13 SARS-CoV-2-infected patients and six controls were analyzed. We found an increase in CXCL10 and IL-6, whose levels remained elevated for up to 3 weeks after symptom onset. SARS-CoV-2 infection also induced CCL2 and GM-CSF, suggesting local recruitment and activation of myeloid cells. Local cytokine levels correlated with viral load but not with serum cytokine levels, nor with specific symptoms, including anosmia. Some patients had S1-specific IgA in the nasal cavity while almost none had IgG.

Conclusion

The nasal epithelium is an active site of cytokine response against SARS-CoV-2 that can last more than 2 weeks; in this mild COVID-19 cohort, anosmia was not associated with increases in any locally produced cytokines.

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