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71.
PURPOSE: To compare success rates for dental implants placed from 1985 through 1988 and from 1989 through 1991, and to investigate the factors associated with success or failure. PATIENTS AND METHODS: All hydroxylapatite-coated cylindrical implants placed from 1985 through 1991 were followed yearly. Lifetable survival analyses compared implant success for a "developmental period" from 1985 through 1988 (4 to 8 years follow-up) and a "recent period" from 1989 through 1991 (1 to 4 years follow-up). Reasons for success or failure, time from implant placement to removal related to failure reason, outcome after implant removal, and a morbidity analysis are included. RESULTS: The 7 to 8-year cumulative success rate for all implants placed in the developmental period (maxilla and mandible combined) was 86.5%; it was 84.2% for all maxillary implants and 87.5% for all mandibular implants. The cumulative success rate for all implants placed in the recent period was 97.5%; it was 97.5% for all maxillary implants and 97.6% for all mandibular implants. The difference between the two periods was statistically significant only for the anterior maxilla. Regression analysis on the interval success rates indicates that interval failure did not follow a linear relationship with time. The most common reasons associated with failure were lack of keratinized gingiva, poor oral hygiene, mechanical overload, and malposition. CONCLUSION: Comparison with previously reported cumulative success rates indicated learning curve experiences comparable with other implant systems. Improvements in hardware, surgical and prosthetic techniques, and patient selection have led to an improvement in success rates with the recent period implants. 相似文献
72.
T Risberg E Lund E Wist O Dahl S Sundstr?m OK Andersen S Kaasa 《Canadian Metallurgical Quarterly》1995,(11):1785-1789
A national multicentre study was performed to investigate the prevalent use of "alternative medicine", here called "non-proven therapies (NPT)", applied among Norwegian cancer patients. Of 911 patients invited to take part in the study, 642 were included in the analysis. Demographic characteristics were collected for all patients. The participating physicians gave information about the patients' clinical characteristics. Among 630 evaluable patients, 20% had been or were present users of NPTs for their oncological disease. The preferred methods were healing by hand and faith healing. Herbs, vitamins, diets and Iscador were other popular methods. As many as 40% of the users of NPTs had used NPTs earlier for non-malignant diseases. Elderly patients were less likely to use NPTs. Use was high in the northern part of Norway. 相似文献
73.
Jibo Qin Yibo Dou Jianchi Zhou Victor M. Candelario Henrik Rasmus Andersen Claus Hélix-Nielsen Wenjing Zhang 《Advanced functional materials》2023,33(28):2214839
The conversion of waste plastic into high-value-added chemicals is regarded as a promising approach for relieving global plastic pollution and contributing to the circular economy. Herein, a partial calcination strategy is developed to fabricate a zinc oxide/UiO66-NH2 (ZnO/UiO66-NH2) heterojunction, in which ZnO is encapsulated in porous UiO66-NH2 for the photocatalytic valorization of plastic. This strategy preserves the framework structure of UiO66-NH2, thus enabling the formation of ZnO with ultra-small size distributed inside the skeleton. The synergistic effect of the obtained ZnO/UiO66-NH2 heterojunction facilitates providing an efficient channel for carrier/mass transfer and guarantees structural stability. As a result, ZnO/UiO66-NH2 exhibits high activity for converting polylactic acid (PLA) and polyvinyl chloride (PVC) into acetic acid, coupled with H2 production. This work provides a feasible strategy for rationally designing heterojunction photocatalysts, as well as an insight into understanding the process of photocatalytic valorization of plastic. 相似文献
74.
This study assesses how social desirability affects responses in clinical self-report inventories. Six hundred items gathered from four normal personality questionnaires were adapted to devise a pre-experimental personality questionnaire (pre-EMHQ). Results obtained from administering Ko's Mental Health Questionnaire (KMHQ) and the pre-EMHQ to separate samples were the proportion of individuals answering "true" to each item (i.e., P(t)) and the social desirability scale value (i.e., SDSV) of each item. The Experimental Mental Health Questionnaire (EMHQ) was established from the pre-EMHQ by closely matching the P(t)s and the SDSVs of the two questionnaires. Administering the KMHQ and the EMHQ concurrently to another sample provided results for factor analysis and other statistical analyses. The SDSVs and the P(t)s for each of the KMHQ items certainly displayed a linearly increasing relation. The two sets of corresponding subscales also correlated significantly. By applying the polynomial regression analysis, the tendency to score might be expressed as a quadratic function of SDSVs. Two iterative principal-factor analyses of the two sets of subscales each resulted in two factors, and Factor 1 is similar in both the KMHQ and the EMHQ. In brief, social desirability plays a critical role in affecting responses in a clinical self-report inventory. The factors involved and suggestions proposed will be of value for further research. 相似文献
75.
There is growing evidence that face recognition is "special" but less certainty concerning the way in which it is special. The authors review and compare previous proposals and their own more recent hypothesis, that faces are recognized "holistically" (i.e., using relatively less part decomposition than other types of objects). This hypothesis, which can account for a variety of data from experiments on face memory, was tested with 4 new experiments on face perception. A selective attention paradigm and a masking paradigm were used to compare the perception of faces with the perception of inverted faces, words, and houses. Evidence was found of relatively less part-based shape representation for faces. The literatures on machine vision and single unit recording in monkey temporal cortex are also reviewed for converging evidence on face representation. The neuropsychological literature is reviewed for-evidence on the question of whether face representation differs in degree or kind from the representation of other types of objects. 相似文献
76.
Herpes simplex virus type 1 (HSV-1) DNA replication intermediates exist in a complex nonlinear structure that does not migrate into a pulsed-field gel. Genetic evidence suggests that the product of the UL12 gene, termed alkaline nuclease, plays a role in processing replication intermediates (R. Martinez, R. T. Sarisky, P. C. Weber, and S. K. Weller, J. Virol. 70:2075-2085, 1996). In this study we have tested the hypothesis that alkaline nuclease acts as a structure-specific resolvase. Cruciform structures generated with oligonucleotides were treated with purified alkaline nuclease; however, instead of being resolved into linear duplexes as would be expected of a resolvase activity, the artificial cruciforms were degraded. DNA replication intermediates were isolated from the well of a pulsed-field gel ("well DNA") and treated with purified HSV-1 alkaline nuclease. Although alkaline nuclease can degrade virion DNA to completion, digestion of well DNA results in a smaller-than-unit-length product that migrates as a heterogeneous smear; this product is resistant to further digestion by alkaline nuclease. The smaller-than-unit-length products are representative of the entire HSV genome, indicating that alkaline nuclease is not inhibited at specific sequences. To further probe the structure of replicating DNA, well DNA was treated with various known nucleases; our results indicate that replicating DNA apparently contains no accessible double-stranded ends but does contain nicks and gaps. Our data suggest that UL12 functions at nicks and gaps in replicating DNA to correctly repair or process the replicating genome into a form suitable for encapsidation. 相似文献
77.
78.
Compact telescope configurations incorporating a holographic correction of large, low-quality primary collectors are demonstrated. Aberration correction is demonstrated with an off-axis laser beacon located close to the primary. This arrangement results in a compact telescope with minimum obscuration. The reduction of additional off-axis aberrations introduced by the method is also demonstrated. 相似文献
79.
JS Andersen 《Canadian Metallurgical Quarterly》1996,6(4):515-522
At times, clinical trial design presents difficult problems for the consulting statistician. The nature of the disease under study or the inadequacies of standard methodology often suggest alternative strategies for the development of useful clinical trial designs. This paper examines two case of novel clinical trial designs that are "made-to-order" for the problem at hand. Both address disease-specific issues. The first case considers the use of adaptive allocation of treatments to patients in a trial in major depressive disorder. The second case reviews the design of a novel efficacy parameter in advanced pancreatic cancer. 相似文献
80.
BACKGROUND: Clinical manifestations and course of sickle-cell anemia are variable. Knowledge about the factors, possibly geographic, that influence prognosis are still scanty. POPULATION AND METHODS: Data of hospitalization and management of children with sickle-cell disease were studied during two years (1992-1993) in the Pediatric Unit of Libreville Hospital. They concerned 205 admissions of 171 children and 131 outpatients. RESULTS: The main causes of hospitalization were: acute anemia (36 cases before the age of 5 years); painful crisis whose frequency increased with age (23% before 5 years, 35% between 5 and 10, 42% after 10 years); infections, essentially pulmonary occurring early, and bone infections at any age. Eight children died (because a complication of their disease). Among the 131 outpatients, half were detected because pyrexia, anemia and/or more often "hand-foot syndrome". More than 60% had hepatomegaly, one third still had splenomegaly after five years of age and more than one third was icteric. More than half children older than ten years had growth disorders. Mean hemoglobin level was 7 g/dL. 21 of the 83 tested children for HBsAg were positive and only one out of 79 was positive for HIV. CONCLUSIONS: Clinical manifestations and course of sickle-cell anemia in our patients are similar to those reported in Congolese children. Genetic and environmental factors may be responsible for differences with children from other, in particular French, cohorts. 相似文献