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51.
P Milgrom P Weinstein P Ratener W A Read K Morrison 《American journal of public health》1978,68(4):394-401
This paper reports the dental care norms for restorative dentistry collected from examinations of 1,466 patients in 105 dental offices in Washington State during 1976. These results are part of a larger study, "Assessment of Care and Continuing Dental Education," being conducted by the University of Washington with the endorsement and cooperation of the Washington State Dental Association. Treatments in volunteer offices were evaluated either by colleagues (peer review) or by the practitioner himself (self-assessment). Two hundred twenty-four of 1,196 eligible dentists volunteered for the study. Patients from the practitioners' offices were randomly selected from office files by project staff. The study tests the proposition that, using standardized clinical evaluation procedures and comparable samples of treatment, dentists will be more critical of their own work than that of others. Results suggest a generally high level of care provided by volunteer practitioners and that self-assessments were significantly more critical than peer review. 相似文献
52.
During the past nine years, 54 patients underwent interposition graft shunting for variceal bleeding in 48 and intractable ascites in six, either electively (35 instances) or as an emergency (13 instances). Autogenous jugular was used in 41 instances, homologous vena cava in nine and Dacron in five. The interposition graft was placed between superior mesenteric vein and vena cava in 36 instances and the portal vein and vena cava in 19. Using Child's Clinical Classification 44 were Class C and 10 Class B. There were six (11%) operative deaths with one (2.4%) in the elective and five (38%) in the emergency group. Encephalopathy was seen in 4 (10%) of those surviving more than one year. Two Dacron and two homografts thrombosed. Eight of the autografts were patent at autopsy, 18 on angiography and 15 assumed to be patent because patients were asymptomatic. Only one of 12 late deaths was related to grafts failure. Apparently the operation controls ascites and the autogenous jugular vein is the ideal material. Interposition "H" grafting is a simple safe procedure that can be used for portal decompression in patients with bleeding varices. 相似文献
53.
S M Walton M J Maresh A Murray M D Read J J Walker 《Clinical and experimental obstetrics & gynecology》1992,19(1):5-8
151 primigravid patients with Bishop scores of 4 or less were induced with prostaglandin E2 gel using an initial dose of 2 mg followed by 1 mg or 2 mg at 6 hours. Eighty one patients (53.6 per cent) were in established labour or had delivered by 12 hours, and a further 31 (20.5 per cent) had achieved successful ripening of the cervix. Ninety per cent and 64.5 per cent respectively achieved vaginal delivery and although 39 patients failed to respond to this regime, 72 per cent delivered vaginally after augmentation. No case of hypertonus was recorded and only one patient had abdominal delivery for "failed induction". This regime provides an effective means of induction of labour for a difficult group of patients with little worry of overstimulation and low "failed induction" rates. 相似文献
54.
Claims regarding amnesia for childhood sexual abuse have often been based on studies of adults' responses to questions of the form, “Was there ever a period of time when you remembered less of the abuse than you do now?” In this experiment, 43 adult (mean age = 42) participants rated their current and prior memories of several nontraumatic childhood/adolescent events. Reports of prior periods of less memory were fairly common. Participants then engaged in “reminiscence” or “enhanced” retrieval activities directed toward remembering more about a selected target event. Following retrieval, 35% of the reminiscence condition participants reported prior poor memory for the target event, as did 70% of the enhanced condition. These results highlight the need for appropriate control conditions in retrospective studies of amnesia for childhood trauma. 相似文献
55.
56.
This project's aim was to assess patients perceived need for a specialist nurse in inflammatory bowel disease. A letter was sent to 64 patients with a summary of the potential role of a specialist nurse. Patients were asked to complete a questionnaire of 10 scenarios on who would be their preferred provider on the range of issues. There were 35 (55%) replies. When comparing the results between the consultant and the specialist nurse patients preferred to see a specialist nurse significantly in four scenarios, and patients preferred to see the consultant significantly in two scenarios. The results indicate that patients feel specialist nurses would have more time to discuss issues and they do not want to bother the busy doctors with them. But they do want doctors to carry out the medical aspects of their care. 相似文献
57.
Inhibition of growth and induction of apoptosis in human cancer cell lines by tea polyphenols 总被引:47,自引:7,他引:47
In order to study the biological activities of tea preparations and
purified tea polyphenols, their growth inhibitory effects were investigated
using four human cancer cell lines. Growth inhibition was measured by
[3H]thymidine incorporation after 48 h of treatment. The green tea
catechins (-)-epigallocatechin-3-gallate (EGCG) and (-)- epigallocatechin
(EGC) displayed strong growth inhibitory effects against lung tumor cell
lines H661 and H1299, with estimated IC50 values of 22 microM, but were
less effective against lung cancer cell line H441 and colon cancer cell
line HT-29 with IC50 values 2- to 3- fold higher.
(-)-Epicatechin-3-gallate, had lower activities, and (-)- epicatechin was
even less effective. Preparations of green tea polyphenols and theaflavins
had higher activities than extracts of green tea and decaffeinated green
tea. The results suggest that the growth inhibitory activity of tea
extracts is caused by the activities of different tea polyphenols. Exposure
of H661 cells to 30 microM EGCG, EGC or theaflavins for 24 h led to the
induction of apoptosis as determined by an annexin V apoptosis assay,
showing apoptosis indices of 23, 26 and 8%, respectively; with 100 microM
of these compounds, the apoptosis indices were 82, 76 and 78%,
respectively. Incubation of H661 cells with EGCG also induced a
dose-dependent formation of H2O2. Addition of H2O2 to H661 cells caused
apoptosis in a manner similar to that caused by EGCG. The EGCG-induced
apoptosis in H661 cells was completely inhibited by exogenously added
catalase (50 units/ml). These results suggest that tea polyphenol-induced
production of H2O2 may mediate apoptosis and that this may contribute to
the growth inhibitory activities of tea polyphenols in vitro.
相似文献
58.
M. A. Richardson Margaret A. Reilly Laura L. Read Cheryl J. Flynn Raymond F. Suckow Timothy J. Maher Istvan Sziraki 《Psychopharmacology》1999,143(4):347-357
Rationale: An association between tardive dyskinesia (TD) and severely impaired metabolism of the large neutral amino acid (LNAA),
phenylalanine (Phe) was defined in a group of mentally retarded patients. Subsequently, an altered kinetics of Phe was associated
with TD in men with schizophrenia based on plasma analyses subsequent to the ingestion of a protein meal. Methods: In the present study, a standardized oral challenge of pure Phe (100 mg/kg in 170 ml orange juice) was administered to psychiatric
patients of both sexes (n = 312), with and without TD after an overnight fast. Plasma LNAA levels were assayed both fasting and 2 h subsequent to the
ingestion of the challenge. The extent of the increase in plasma Phe levels 2 h following a standardized challenge is determined
by the sum of the kinetic processes of plasma absorption, tissue distribution, metabolism and elimination. Results: The study hypothesis, that TD would be associated with significantly higher post-challenge plasma Phe indices of an absolute
plasma Phe level and plasma Phe/LNAA ratio (a brain availability measure), was verified for the study men (n = 209), but not for the study women (n = 103). Conclusions: The demonstrated altered kinetics of Phe in men with TD indicates a greater availability of Phe to the brain in these men.
We suggest that the disorder may be related to the effects of this greater availability. Such effects could be the direct
neurotoxic effects of Phe and its metabolites and/or the modulating effects of these compounds on the synthesis of the monoamine
neurotransmitters. The fact that TD (Yes/No) group differences in post-challenge plasma Phe indices were not seen for the
study women suggests the possibility of a sex difference in the biology of TD that we propose may be reflective of the young
age of the study sample.
Received: 28 January 1998/Final version: 14 December 1998 相似文献
59.
Tim Bergner Fabian Zech Maximilian Hirschenberger Steffen Stenger Konstantin M. J. Sparrer Frank Kirchhoff Clarissa Read 《Viruses》2022,14(12)
Infection with the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative agent of the COVID-19 pandemic, leads to profound remodeling of cellular membranes, promoting viral replication and virion assembly. A full understanding of this drastic remodeling and the process of virion morphogenesis remains lacking. In this study, we applied room temperature transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) tomography to visualize the SARS-CoV-2 replication factory in Vero cells, and present our results in comparison with published cryo-EM studies. We obtained cryo-EM-like clarity of the ultrastructure by employing high-pressure freezing, freeze substitution (HPF-FS) and embedding, allowing room temperature visualization of double-membrane vesicles (DMVs) in a near-native state. In addition, our data illustrate the consecutive stages of virion morphogenesis and reveal that SARS-CoV-2 ribonucleoprotein assembly and membrane curvature occur simultaneously. Finally, we show the tethering of virions to the plasma membrane in 3D, and that accumulations of virus particles lacking spike protein in large vesicles are most likely not a result of defective virion assembly at their membrane. In conclusion, this study puts forward a room-temperature EM technique providing near-native ultrastructural information about SARS-CoV-2 replication, adding to our understanding of the interaction of this pandemic virus with its host cell. 相似文献
60.
Candace Tefertiller Meghan Rozwod Sandra Wojciehowski Mitch Sevigny Susan Charlifue Jessica M. Ketchum Jeffrey Berliner Heather B. Taylor Andrea L. Behrman Susan Harkema Gail Forrest Mary Schmidt Read Michelle Basso 《The journal of spinal cord medicine》2023,46(1):35
Context/Objective:Spinal cord injury (SCI) often results in a significant loss of mobility and independence coinciding with reports of decreased quality of life (QOL), community participation, and medical complications often requiring re-hospitalization. Locomotor training (LT), the repetition of stepping-like patterning has shown beneficial effects for improving walking ability after motor incomplete SCI, but the potential impact of LT on psychosocial outcomes has not been well-established. The purpose of this study was to evaluate one year QOL, community participation and re-hospitalization outcomes between individuals who participated in a standardized LT program and those who received usual care (UC).Design/Setting/Participants:A retrospective (nested case/control) analysis was completed using SCI Model Systems (SCIMS) data comparing one year post-injury outcomes between individuals with traumatic motor incomplete SCI who participated in standardized LT to those who received UC.Outcome Measures:Outcomes compared include the following: Satisfaction with Life Scale (SWLS™), Craig Handicap Assessment and Reporting Technique-Short Form (CHART-SF™), and whether or not an individual was re-hospitalized during the first year of injury.Results:Statistically significant improvements for the LT group were found in the following outcomes: SWLS (P = 0.019); and CHART subscales [mobility (P = <0.001)]; occupation (P = 0.028); with small to medium effects sizes.Conclusion:Individuals who completed a standardized LT intervention reported greater improvements in satisfaction with life, community participation, and fewer re-hospitalizations at one year post-injury in comparison to those who received UC. Future randomized controlled trials are needed to verify these findings. 相似文献