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961.
A general (possibly asymmetric noncausal and/or nonminimum phase) 2D autoregressive moving average random field model driven by an independent and identically distributed 2D nonGaussian sequence is considered. The model is restricted to be invertible, i.e., system zeros are not allowed to lie on the unit bicircle. Three performance criteria are investigated for parameter estimation of the system parameters given only the output measurements (image pixels). The proposed criteria are functions of the higher order cumulant statistics of an inverse filter output. One of these criteria is novel and the others have been considered in past only for moving average inverses and without any analysis of their consistency. In the paper strong consistency of the proposed methods under the assumption that the system order is known is proved. The convergence of the proposed parameter estimators under overparametrization is also analyzed. Experimental results involving synthesized as well as real life textures are presented to illustrate the performance of two of the considered approaches. Experimental results of synthesis of 128x128 textures visually resembling several real life textures in the Brodatz album (and other sources) are presented.  相似文献   
962.
963.
In a prospective study we found good results concerning postoperative complications (21%), perioperative lethality (3.2%) and lethality during hospital stay (6.5%) after implantation of dynamic hip screws (DHS) in patients with per- and subtrochanteric fractures of the femur. The ability to walk, as well as housing and social care postoperatively and follow-up for at least six months after dismissal demonstrates the importance of these fractures for the elderly. One of three patients needs professional care, 21% at home, 13% in nursing homes. Six months after operation the lethality is nearly 20%, i.e. three times higher than in hospital. These are the essential data for all techniques of osteosynthesis used in patients with these fractures, which could only be documented in prospective studies.  相似文献   
964.
965.
This study was done to determine the occurrence of disease in retained ovaries after hysterectomy. A retrospective analysis of patient charts was performed, comparing the patient reports of women who had secondary ovarian lesions with those whose ovaries showed no pathologic findings during the ten year period of observation (1980 to 1990). The study included 1,265 women with at least one ovary saved after hysterectomy for benign indications. Main outcome measures were ovarian pathologic findings after hysterectomy requiring repeat operation. The overall incidence of lesions in retained ovaries was 3.95 percent. There was a 3 percent risk of having secondary ovarian pathologic findings within three years after hysterectomy, with a decreased risk for the following seven years (mean follow-up time of 60 months, range of three to 120 months). Histologic findings at reoperation included common benign conditions of the ovary. No instance of carcinoma of the ovary was found. The risk of having pathology in the retained ovaries after hysterectomy was significantly higher in women who had only one ovary saved, compared with those who had both ovaries saved (7.63 versus 3.47 percent; p < 0.05). The mean age at hysterectomy was significantly lower in women who had ovarian disorders subsequent to hysterectomy than in those who did not (39.3 versus 43.9 years; p < 0.001). In the group of women with secondary ovarian lesions, mean parity was significantly lower than in those without reoperation (1.22 versus 1.94; p < 0.0001). Women with unilateral oophorectomy at the time of hysterectomy had twice the risk of secondary ovarian lesions, compared with those without oophorectomy at hysterectomy. Determinants, such as age, parity and gravidity must be considered when deciding whether or not to perform oophorectomy at hysterectomy.  相似文献   
966.
Ambiguous abdominal situs, asplenia/polysplenia and severe cardiac malformations characterize heterotaxy in humans. These anomalies result from the inability of the developing embryo to establish normal left-right asymmetry. We have studied an interesting family in which the heterotaxy phenotype segregates as an X-linked recessive trait. In order to map the heterotaxy locus (HTX), we have analysed 39 family members using highly-polymorphic microsatellite markers from the X chromosome. One of these markers, DXS994, shows no recombination with the disease locus in 20 informative meioses. Linkage analysis results in a maximum lod score of 6.37. Current genetic and physical mapping data assign the order of loci in Xq24-q27.1 as cen-DXS1001-(DXS994, HTX)-DXS984-tel. These results establish the first mapping assignment of situs abnormalities in humans.  相似文献   
967.
Fracture mechanics tests have been performed in the upper shelf region of a steel on large surface cracked plate (SCT) specimens and on small compact tension (CT) specimens. Some of the SCT specimens were subjected to combined tension and bending in such a way that the loading was strongly non-proportional. Crack growth characteristics were compared between the specimens in order to assess possible influences of geometry and nonproportional loading. The differences observed could unambiguously be reduced to and correlated with differences in constraint. Constraint parameters were evaluated by detailed three-dimensional finite element computations and quantities for growing cracks were interpreted on the basis of deformation theory considerations, in analogy with the commonly used J R-philosophy. It was noted that the initiation of ductile crack growth along a three-dimensional crack front appears to be independent of the degree of local constraint. However, the increase in toughness for a growing crack was markedly affected by the degree of local constraint. Some estimates of the constraints effects regarding stability considerations were also made.  相似文献   
968.
969.
970.
This article presents the results of a pilot-study conducted on a small sample of women with breast cancer and the members of their social support system. The purpose was to determine the potential link between the mental health of the breast cancer patient and their support system. Mental health was assessed with the SCL-90-R (Derogatis, 1977), a self-report scale composed of 90 items divided into nine categories, offering three global indicators of distress: the Global Severity Index (GSI); the Positive Symptom Distress Index (PSDI), and the Positive Symptom Total (PST). The SCL-90-R was distributed to a sample of 14 subjects: seven women treated for breast cancer and seven significant others (social support). The results led to the definition of symptoms such as hostility, phobic anxiety and psychosis specific to either the woman or the support system.  相似文献   
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