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101.
Different incidence rates of new diabetic patients on dialysis are reported in various settings; although prevalence of this disease is often considered a marker of acceptance policy, rates are thought to be influenced also by genetic, epidemiological and other characteristics of a population (genetic composition, age distribution, lifestyle). Moreover, since features of a general population are often not stable (as in the setting analysed) changes at this level may have important reflections in the incidence of diabetics with end-stage renal disease (ESRD). In the region studied (Piedmont, northern Italy, about 4400 000 inhabitants, 20 dialysis centres, open acceptance since the mid-1970s, yearly information on 100% of patients, gathered by a Dialysis and Transplantation Registry) the incidence of diabetic patients with ESRD (389 cases recorded 1981–1990: 222 males, 167 females: mean age at start increasing from 55.5 years in 1981–1985 to 58.7 years in 1986–1990) differs according to age and sex. Incidence was higher in males, and rose from 6.23/year patients per million population (p.m.p.) in 1981–1982 to 12.88/year p.m.p. in 1989–1990, with a peak at age 60–69 (from 18.46/year p.m.p. in 1981–1982, to 46.12/year p.m.p. in 1989–1990). While relatively stable in the younger age groups from 1981 to 1990, incidence increased in the elderly (males age 70–79: 7.12/year p.m.p. in 1981–1982, 26.08/year p.m.p. in 1989–1990). As regards clinical and metabolic patterns, at the first update, in 1986–1990, 88.3% of diabetic patients were hypertensive or taking hypotensive drugs; albumin levels were below the normal range (<3.5 g/dl) in 30.3%; cholesterol levels were below the normal range (<150 mg/dl) in 16.15%. As regards entry criteria, creatinine clearances ranged from <1 to 14 ml/min (mean values at first update: 3.45±2.76 ml/min). In conclusion, presentation of diabetic patients with ESRD is changing. The stability of incidence in the younger age groups confirms the appropriateness of an open acceptance policy, at least for these ages. The increase in the elderly probably reflects the longer lifespan of diabetic patients in the overall population, while the influence of a hidden preselection must be further assessed. Since this cohort increasingly requires in-hospital high-tolerance treatment, future provision of dialysis needs must take into account the trend towards an increase in this high-risk elderly population.  相似文献   
102.
Canine renal cortical PTH receptors were solubilized after occupancy of membrane-associated receptors with the agonist ligand [125I]bovine (b) PTH-(1-34). Stabilization of binding during solubilization required the use of high concentrations of BSA (optimally 5%) and appropriate detergents (0.5% 3-[(3-cholamidopropyl)dimethylammonio]2-hydroxy-1-propanesulfonate, 0.5% 3-[(3-cholamidopropanyl)dimethylammonio]1-propanesulfonate, or 0.5-1.0% digitonin). The soluble fraction (240,000 X gav supernatant) contained [125I]bPTH-(1-34) associated with macromolecular components as well as unbound [125I]bPTH-(1-34) that dissociated during solubilization. The soluble macromolecular complex had functional properties expected of a ternary complex consisting of [125I]bPTH-(1-34) receptor stimulatory guanine nucleotide-binding protein (Ns). Thus, the dissociation of labeled PTH at 30 C was slow (t1/2 = 75 min); in the presence of GTP (10(-4) M), 75% of the sites displayed rapid dissociation kinetics (t1/2 = 2.3 min). This effect was nucleotide specific, with GTP approximately equal to GTP gamma S approximately equal to GDP greater than GDP beta S greater than ITP approximately equal to guanylylimidodiphosphate much greater than GMP approximately equal to App(NH)p. ATP was ineffective. GTP produced a half-maximal response at a concentration of 200 nM. These results are consistent with the reported nucleotide specificity and affinity of purified Ns. Treatment of membranes with N-ethylmaleimide during the binding reaction rendered the solubilized complex refractory to GTP. Gel filtration chromatography (Sepharose 6B) revealed a GTP-sensitive complex that eluted in the position expected of a detergent-free spherical protein of 180,000 daltons. This complex may consist of the 60,000 to 70,000-dalton PTH-binding subunit (previously identified by photoaffinity labeling) together with Ns.  相似文献   
103.
104.
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   
105.
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   
106.
107.
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   
108.
109.
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   
110.
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   
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