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941.
Knobloch L Larsen PA Rashid B Carr AB 《The International journal of oral & maxillofacial implants》2004,19(3):350-356
PURPOSE: The purpose of this study was to compare machined-surface implants (control) and oxidized-surface titanium screw-type implants (test) loaded with fixed partial dentures at 2, 4, and 6 weeks postplacement in terms of implant survival and stability. MATERIALS AND METHODS: The beagle model was chosen for the study. Four mandibular premolars were extracted bilaterally from each dog. After 2 months of healing, 4 implants were placed in each dog. Half of the dogs (n = 6), the test group, received oxidized-surface implants; the other half (n = 6), the control group, received machined-surface implants. In each group, 2 dogs were randomly assigned to a 2-week preloading healing period, 2 to a 4-week period, and 2 to a 6-week period. Three implants were loaded in each dog; 1 was left unloaded as a control. Clinical stability and survival were monitored every 2 weeks for 6 months. RESULTS: Failures were noted only among the implants assigned to the 2- and 4-week groups. Failures accounted for 9.4% (9/96) of the implants--12.5% (6/48) of the control implants and 6.3% (3/48) of the test implants. One hundred percent prosthesis stability was noted for the test-surface implant group. Stability of the test implants was significantly better than stability of the control implants (-2.6 vs -1.7, P < .05). Mean Periotest values at loading were 3.7 for the group loaded at 2 weeks, 1.6 for the group loaded at 4 weeks, and 0.6 for the group loaded at 6 weeks. Fifty percent of the 6-week group, 25% of the 4-week group, and 12.5% of the 2-week group had a Periotest value < 0 at loading. DISCUSSION: The results reveal a qualitative difference in performance between the implant groups. Twice as many failures occurred in the control group, few failures occurred following loading, and no failures occurred after 4 weeks postplacement. The survival curves for both implants were flat after 4 weeks; however, the duration of follow-up may hide effects of time-dependent factors on survival and poses a concern for clinical inference. CONCLUSIONS: Early loading of both implant types was well tolerated, as only 2 failures occurred following loading. A subsequent report will review these outcomes along with histomorphometric data collected at 6 months to better understand the significance of tissue-level implant-surface interaction for survival and stability. 相似文献
942.
STUDY OBJECTIVES: To evaluate the incidence, patient characteristics, and clinical significance of segmental early relaxation phenomenon (SERP) in stress echocardiography. DESIGN: Retrospective interpretation of digitized rest/stress echocardiographic images of 244 consecutive patients undergoing exercise or dobutamine echocardiography with subsequent patient follow-up for outcomes. SETTING: Tertiary care referral center. PATIENTS: Two hundred forty-four consecutive patients referred for stress echocardiography (exercise or dobutamine) for various clinical indications. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: SERP was diagnosed as a sudden outward motion of a portion of the left ventricle during early diastole (using frame-by-frame analysis) after peak systole prior to mitral valve opening at rest and after stress. Stress-associated SERP was observed in 71 patients (29.1%), with 25 patients having SERP in more than one segment. Five patients had resting SERP, with two persisting during stress. Ninety-six of 3,658 analyzed segments were positive for SERP. The apical septum and midseptum were most commonly involved in 49% and 18%, respectively. Only 5 of 96 patients (5.2%) had new hypokinesis and SERP in the same segment. No significant differences existed in demographic, clinical, or echocardiographic variables in patients with and without SERP. Follow-up revealed no significant differences in event rates in those with and without SERP. CONCLUSIONS: This is the first stress echocardiographic study demonstrating that SERP is a distinct and relatively common stress echocardiographic phenomenon occurring in early diastole regardless of type of stress. SERP occurs predominantly in apical and midseptum in the distribution of the left anterior descending coronary artery. It should not be mistaken for atypical septal motion, ischemia, or dyskinesia, and does not seem related solely to the presence of underlying coronary disease or stress-induced ischemia. No adverse long-term outcomes are seen in patients with SERP and no inducible ischemia. 相似文献
943.
944.
Mugusi F Edwards R Hayes L Unwin N Mbanya JC Whiting D Sobngwi E Rashid S 《Tropical doctor》2004,34(4):209-214
We investigated the prevalence of wheeze, self-reported asthma, and asthma care via four cross-sectional surveys among adults and children (5-15 years) in urban and rural populations from Tanzania and Cameroon. Age-standardized prevalence of current wheeze (in the previous year) was 2.2% to 5.0% in adults and 1.9% to 5.2% in children in Tanzania, and 1.3% to 2.5% (adults) and 0.8% to 5.4% (children) in Cameroon. There were no consistent patterns of urban:rural prevalence. Peak flow rates varied with age, peaking at 25-34 years, and were higher in urban areas (age adjusted difference 22-70 L/min) and in the Tanzania populations. Awareness (83%-86% versus 52%-58%) and treatment (43%-71% versus 30%-44%) of asthma was higher among those with current wheeze in rural areas. Use of inhaled drugs, particularly steroids, was rare. Diagnosis by traditional healers (15%) and use of traditional remedies (62% of those recalling any treatment) were common only among self-reported asthmatic patients in rural Cameroon. Asthma is an importantclinical condition in sub-Saharan Africa. There were major gaps in clinical care, particularly in urban areas. Sustainable methods for delivering accessible and effective asthma care in sub-Saharan Africa are required. 相似文献
945.
The serotonin (5-hydroxytryptamine, 5-HT) receptors have conventionally been divided into seven subfamilies, most of which have several subtypes. Among them, 5-HT(2A) receptor is associated with the contraction of vascular smooth muscle, platelet aggregation and thrombus formation and coronary artery spasms. Accordingly, selective 5-HT(2A) antagonists may have potential in the treatment of cardiovascular diseases. Sarpogrelate, a selective 5-HT(2A) antagonist, has been introduced clinically as a therapeutic agent for the treatment of ischemic diseases associated with thrombosis. Molecular modeling studies also suggest that sarpogrelate is a 5-HT(2A) selective antagonist and is likely to have pharmacological effects beneficial in the treatment of cardiovascular diseases. This review describes the above findings as well as the signaling linkages of the 5-HT(2A) receptors and the mode of agonist binding to 5-HT(2A) receptor using data derived from molecular modeling and site-directed mutagenesis. 相似文献
946.
947.
Rashid T Leirisalo-Repo M Tani Y Hukuda S Kobayashi S Wilson C Bansal S Ebringer A 《Clinical rheumatology》2004,23(2):134-141
It has been suggested that Proteus infection may be involved in the pathogenesis of rheumatoid arthritis (RA). Bacterial and peptide immune responses in patients with RA and other control subjects were investigated in two geographically different populations. Serum samples from Finnish patients with early (n=72) and advanced (n=27) RA and 30 Finnish healthy controls, as well as from Japanese RA patients from two different locations: Tokyo (n=30) and Otsu (n=30), 18 patients with systemic lupus erythematosus (SLE) and 23 Japanese healthy controls were all screened for the total, and class-specific (IgG, IgA and IgM) antibodies against Proteus mirabilis, Escherichia coli and Serratia marcescens by indirect immunofluorescence assay. These samples were also tested for the determination of levels of isotypic antibodies against the shared epitope involving 16-mer synthetic peptides containing the EQRRAA or ESSRAL sequences and compared to scrambled control peptide by using an enzyme-labeled immunosorbent assay method. Significantly elevated levels of IgG and IgM antibodies to P. mirabilis and antibodies against both EQRRAA and ESSRAL peptides were detected in sera of Finnish patients with early and advanced RA, and in Japanese patients from Otsu or Tokyo compared to their corresponding control groups. In contrast, no difference either in the total or in any of the isotypic antibodies were observed between these groups when serum samples were screened against each of E. coli and S. marcescens or against the control peptide. Furthermore, there was a significant correlation between the antibody levels against Proteus bacteria only and both EQRRAA and ESRRAL peptides. Our findings support the possibility for specific involvement of P. mirabilis in the etiopathogenesis of RA even in early cases.Abbreviations ELISA Enzyme linked immunosorbent assay - IIF Immunofluorescence - RA Rheumatoid arthritis - SLE Systemic lupus erythematosus 相似文献
948.
A pulmonary giant hydatid cyst, a special clinical entity, is rare. Our case involves a young patient who presented with a bilaterally symmetrical solitary cyst in each lung, a feature consistent with congenital lung cysts. The radiological and immunological findings were equivocal. A diagnosis of giant hydatid cyst was made intraoperatively and both cysts were removed conservatively. A follow-up showed complete recovery. 相似文献
949.
950.