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381.
Sasha Shepperd Helen Doll Robert M. Angus Mike J. Clarke Steve Iliffe Lalit Kalra Nicoletta Aimonio Ricauda Vittoria Tibaldi Andrew D. Wilson 《CMAJ》2009,180(2):175-182
Background
Avoidance of admission through provision of hospital care at home is a scheme whereby health care professionals provide active treatment in the patient''s home for a condition that would otherwise require inpatient treatment in an acute care hospital. We sought to compare the effectiveness of this method of caring for patients with that type of in-hospital care.Methods
We searched the MEDLINE, EMBASE, CINAHL and EconLit databases and the Cochrane Effective Practice and Organisation of Care Group register from the earliest date in each database until January 2008. We included randomized controlled trials that evaluated a service providing an alternative to admission to an acute care hospital. We excluded trials in which the program did not offer a substitute for inpatient care. We performed meta-analyses for trials for which the study populations had similar characteristics and for which common outcomes had been measured.Results
We included 10 randomized trials (with a total of 1327 patients) in our systematic review. Seven of these trials (with a total of 969 patients) were deemed eligible for meta-analysis of individual patient data, but we were able to obtain data for only 5 of these trials (with a total of 844 patients [87%]). There was no significant difference in mortality at 3 months for patients who received hospital care at home (adjusted hazard ratio [HR] 0.77, 95% confidence interval [CI] 0.54–1.09, p = 0.15). However, at 6 months, mortality was significantly lower for these patients (adjusted HR 0.62, 95% CI 0.45–0.87, p = 0.005). Admissions to hospital were greater, but not significantly so, for patients receiving hospital care at home (adjusted HR 1.49, 95% CI 0.96–2.33, p = 0.08). Patients receiving hospital care at home reported greater satisfaction than those receiving inpatient care. These programs were less expensive than admission to an acute care hospital ward when the analysis was restricted to treatment actually received and when the costs of informal care were excluded.Interpretation
For selected patients, avoiding admission through provision of hospital care at home yielded similar outcomes to inpatient care, at a similar or lower cost.In many countries, programs in which hospital care is provided in the patient''s own home continue to be a popular response to the increasing demand for acute care hospital beds. Patients who received care through such programs, after assessment in the community by their primary care physician or in the emergency department, may avoid admission to an acute care ward. Alternatively, patients may be discharged early from hospital to receive hospital care at home. We have conducted a parallel systematic review and meta-analysis of individual patient data related to hospital care at home for patients who have received early discharge, which we will report separately. Recently, the emphasis has been on avoiding admission to hospital, which reflects the relatively limited gain from discharging patients early after a stay in hospital, given the universal trend for shorter lengths of stay in hospital.The types of patients receiving hospital care at home differ among schemes, as does the use of technology. Some schemes are designed to care for patients with specific conditions, such as chronic obstructive pulmonary disease, or to provide specific skills, such as parenteral nutrition. However, many schemes for the provision of hospital care at home lack such clear functions and have an “open door” policy covering a wide range of conditions. These schemes may build on existing community resources, or they may operate as hospital outreach services, with hospital staff making home visits. In particular, “hospital-at-home” programs are defined by the provision, in patients'' own homes and for a limited period, of a specific service that requires active participation by health care professionals. The care tends to be multidisciplinary and may include technical services, such as intravenous services.Cutting costs by avoiding admission to hospital altogether is the central goal of such schemes. Other perceived benefits include reducing the risk of adverse events associated with time in hospital1 and the potential benefit of receiving rehabilitation in the home environment. However, it is not known if patients covered by a policy of avoiding admission through the provision of hospital care at home have health outcomes better than or equivalent to those of patients who receive inpatient hospital care. Furthermore, it is not known if the provision of hospital care at home results in a reduction or an increase in costs to the health service. We conducted a systematic review and meta-analysis, using individual patient data and published data, to determine the effectiveness and cost of managing care of patients through the provision of hospital care at home relative to inpatient hospital care. The meta-analysis of individual patient data allowed us to investigate whether the strategies were associated with key events happening after different periods of time, rather than simply whether or not those events occurred. 相似文献382.
383.
In seeking to ease the rehabilitation of refugees there has generally been a failure to take account of the complexity of the refugees' experience of suffering and loss. In this their psychological and emotional well-being as well as the social and economic aspects of the question have frequently been of only peripheral concern, and the response to the psychological impact of violence has been primarily focused on the concept of Post-Traumatic Stress Disorder (PTSD). This approach assumes a pathological response to stress that is both universal across different cultures and centred on the potential of pathologizing coping strategies that might be essential not only for survival but also for psychological well-being. 相似文献
384.
Vittoria Di Martino Rigano Vincenza Vona Amodio Fuggi Carmelo Rigano 《Physiologia plantarum》1982,54(1):47-51
In the unicellular alga Cyanidium caldarium nitrate utilization is strongly inhibited by ammonium and it is resumed when ammonium has been depleted. In the presence of L-methionine-DL-sulphoximine (MSX), which prevents ammonium assimilation through a specific irreversible inhibition of glutamine synthetase, nitrate reduction is no longer inhibited by ammonium, and most of the ammonium derived from nitrate reduction is excreted into the external medium. However, in the presence of MSX, nitrate reduction to ammonium proceeds at a reduced rate (45 to 70% of the control); this is particularly marked at low nitrate concentration. It is hypothesized that either MSX or accumulating ammonium bring about decrease in the rate of nitrate entry into the cell. 相似文献
385.
Carmelo Rigano Vittoria Di Martino Rigano Vincenza Vona Amodio Fuggi 《Archives of microbiology》1979,121(2):117-120
Addition ofl-methionine-dl-sulphoximine to cells ofCyanidium caldarium brings about a loss of glutamine synthetase activity. Concomitantly ammonia assimilation is prevented.Under physiological conditions nitrate reductase [NAD(P)H: nitrate oxidoreductase EC 1.6.6.2] is reversibly converted into an inactive enzyme upon addition of ammonia. In the presence of methionine sulphoximine, when glutamine synthetase activity is lost, nitrate reductase is no longer inactivated by ammonia. It is suggested that ammonia itself is not the actual effector of nitrate reductase inactivation.Concomitantly with the failure of nitrate reductase to undergo ammonia-inactivation, in the presence of methionine sulphoximine nitrate reduction is an uncontrolled process, thus, in media with nitrate ammonia continues to be produced and excreted into the external medium at a constant rate.Abbreviations NR
Nitrate reductase
- GS
Glutamine synthetase
- GOGAT
Glutamate syntase
- MSX
l-methionine-dl-sulphoximine 相似文献
386.
Philip E. Thompson Vittoria Cavallaro Milton T. W. Hearn 《Letters in Peptide Science》1995,1(6):263-268
Summary Experimental conditions which influence the formation of -aminosuccinimide (Asu) structures in Fmoc-based SPPS have been examined as part of our work on the synthesis of the hypoglycaemic peptide, Asu11-hGH[6–13] amide, and its analogues. Based on these investigations, experimental conditions for the acid- and base-catalysed cyclization of the corresponding protected aspartyl-containing peptides have been optimized to provide improved yields and reduced side product formation of these -aminosuccinimide-containing peptides. 相似文献
387.
Regulation of sucrose and starch metabolism in potato tubers in response to short-term water deficit 总被引:24,自引:0,他引:24
Peter Geigenberger Ralph Reimholz Michael Geiger Lucia Merlo Vittoria Canale Mark Stitt 《Planta》1997,201(4):502-518
To investigate the effect of water stress on carbon metabolism in growing potato tubers (Solanum tuberosum L.), freshly cut and washed discs were incubated in a range of mannitol concentrations corresponding to external water potential
between 0 and −1.2 MPa. (i) Incorporation of [14C]glucose into starch was inhibited in water-stressed discs, and labeling of sucrose was increased. High glucose overrode
the changes at low water stress (up to −0.5 MPa) but not at high water stress. (ii) Although [14C]sucrose uptake increased in water-stressed discs, less of the absorbed [14C]sucrose was metabolised. (iii) Analysis of the sucrose content of the discs confirmed that increasing water deficit leads
to a switch, from net sucrose degradation to net sucrose synthesis. (iv) In parallel incubations containing identical concentrations
of sugars but differing in which sugar was labeled, degradation of [14C]sucrose and labeling of sucrose from [14C]glucose and fructose was found at each mannitol concentration. This shows that there is a cycle of sucrose degradation and
resynthesis in these tuber discs. Increasing the extent of water stress changed the relation between sucrose breakdown and
sucrose synthesis, in favour of synthesis. (v) Analysis of metabolites showed a biphasic response to increasing water deficit.
Moderate water stress (0–200 mM mannitol) led to a decrease of the phosphorylated intermediates, especially 3-phosphoglycerate
(3PGA). The decrease of metabolites at moderate water stress was not seen when high concentrations of glucose were supplied
to the discs. More extreme water stress (300–500 mM mannitol) was accompanied by an accumulation of metabolites at low and
high glucose. (vi) Moderate water stress led to an activation of sucrose phosphate synthase (SPS) in discs, and in intact
tubers. The stimulation involved a change in the kinetic properties of SPS, and was blocked␣by protein phosphatase inhibitors.
(vii) The amount of ADP-glucose (ADPGlc) decreased when discs were incubated on 100 or 200 mM mannitol. There was a strong
correlation between the in vivo levels of ADPGlc and 3PGA when discs were subjected to moderate water stress, and when the
sugar supply was varied. (viii) The level of ADPGlc increased and starch synthesis was further inhibited when discs were incubated
in 300–500 mM mannitol. (ix) It is proposed that moderate water stress leads to an activation of SPS and stimulates sucrose
synthesis. The resulting decline of 3PGA leads to a partial inhibition of ADP-glucose pyrophosphorylase and starch synthesis.
More-extreme water stress leads to a further alteration of partitioning, because it inhibits the activities of one or more
of the enzymes involved in the terminal reactions of starch synthesis.
Received: 26 August 1996 / Accepted: 5 November 1996 相似文献
388.
Lavinia Vittoria Lotti Maria Rosaria Torrisi Maria Carmen Erra Stefano Bonatti 《Experimental cell research》1996,227(2):323
Vero cells were infected with the ts-045 strain of vesicular stomatitis virus, and the cells were incubated at 39°C to accumulate the mutant G glycoprotein in the ER as a misfolded aggregate. Cycloheximide was added to the culture medium 3.5 h after infection to prevent further protein synthesis, and the temperature was lowered to 10, 15, or 31°C. At these temperatures, the mutant G glycoprotein correctly folds and oligomerizes. Immunofluorescence light microscopy showed that the G glycoprotein was exported to the Golgi complex at 31°C and to the intermediate compartment (IC) at 15°C, but no export was observed at 10°C. However, incubations at 10°C followed by shift to 15 or 31°C resulted in the normal transfer of the glycoprotein to the IC and the Golgi, respectively. Immunoelectron microscopical analysis confirmed all these results, but showed also that the glycoprotein was frequently clustered in the ER at 10°C. Conventional electron microscopy showed that the morphology of the ER, IC, and Golgi complex remained essentially unchanged at all temperatures. The only significant difference detectable in cells incubated at 10°C was the increased number of partially coated ER protrusions, longer than those detected at higher temperatures. These results demonstrate that the transport toward the Golgi complex of G glycoprotein can be arrested at a step preceding the entry into the IC, thus suggesting that ER and IC are separate stations in the exocytic pathway. 相似文献
389.
Vittoria Di Martina Rigano Vincenza Vona Sergio Esposito Catello Di Martina Carmelo Rigano 《Journal of phycology》1991,27(2):220-223
The possible origin of carbon skeletons for ammonium assimilation in Cyanidium caldarium (Tilden) Geitler was investigated. N-sufficient cells assimilated ammonium at a rate of 182 ± 18 μmol·mL packed cell volume (pcv)-1· h-1. Removal of CO2 or darkening almost immediately prevented ammonium assimilation. N-limited cells in light assimilated ammonium at a rate of 493 ± 45 μmol · mL pcv-1· h-1 in the presence of CO2 and at a lower rate of 168 ± 17 μmol · mL pcv-1· h-1 in the absence of CO2. In darkness they assimilated ammonium at a rate of 293 ± 29 μmol · mL pcv-1 h-1 in the presence of CO2, only 60% of the assimilation rate in light. In the absence of CO2, ammonium was assimilated at a similar rate of 325 ± 14 μmol · mL pcv-1· h-1. Under the latter conditions, however, assimilation was inhibited after 40 min and ceased after 70 min; it resumed upon resupply of CO2. We suggest that N-sufficient cells of C. caldarium obtain carbon skeletons for ammonium assimilation exclusively by photosynthetic reactions. Upon N-limitation they develop the ability, apparently through derepression or activation of regulatory enzyme system(s), to obtain a consistent quantity of additional carbon skeletons and ATP from mobilization of carbon reserves. This enables the N-limited cell to assimilate ammonium not only in light but also in darkness, and at a higher rate than N-sufficient cells. The fact that ammonium assimilation in light occurs at a higher rate than in darkness suggests that ammonium assimilation in light is the sum of both light and dark ammonium assimilation, which implies separate metabolic reactions for the two processes. These results suggest the existence of two distinct and differently controlled pathways in N-limited cells, but not in N-sufficient cells, through which carbon skeletons for ammonium assimilation originate. An important role for dark CO2 fixation in dark or light ammonium assimilation is also indicated. 相似文献
390.
Vincenza Vona Vittoria Di Martino Rigano Sergio Esposito Petronia Carillo Simona Carfagna Carmelo Rigano 《Physiologia plantarum》1999,105(2):288-293
N-sufficient cells of Chlorella sorokiniana Shihira and Krauss, strain 211/8k, absorbed NH4 + under light plus CO2 conditions, when growth occurred, but not in darkness or in the absence of CO2 , when growth was inhibited. N-sufficient cells subjected to conditions of N-starvation for a 24-h period showed a marked loss of photosynthetic activity. Upon supply of NH4 + , N-starved cells sufflated with CO2 air exhibited a time-dependent recovery of photosynthetic activity, both when suspended in light and in darkness. By contrast, growth only occurred in cells suspended in light. N-starved cells absorbed NH4 + in darkness, but at a lower rate than in light. All of these data suggest that dark NH4 + uptake is driven by N assimilation to recover from N-starvation and that the light-dependent NH4 + uptake is driven by growth, being then influenced by conditions that affect recovery or growth. Unlike CO2 conditions, in a CO2 -free atmosphere, absorption of NH4 + by N-starved cells occurred at a higher rate in darkness than in light. Accordingly, resumption of photosynthetic potential after NH4 + supply occurred in darkened cells, but not in illuminated cells. Respiratory activity of N-starved cells was enhanced up to 3-fold by NH4 + and 2-fold by methylammonium, with different patterns, suggesting that respiratory enzymes were affected by N-metabolism, especially through short-term control mechanisms triggered by the expenditure of metabolic energy involved in N-metabolism. 相似文献