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91.
92.
The radiological findings in five patients with pelvic sort tissue neo plasms directly involving the sacroiliac joint, are described. All patients had Computed Tomography (CT) examinations, two of the patients also having Magnetic Resonance Imaging (MRI). The role of imaging in this uncommon entity is discussed as well as the importance of making this diagnosis, thereby excluding unilateral sacroiliitis. The therapeutic implications of this diagnosis relate to local neural involvement, especially the sciatic nerve, and the fact that involvement of the sacroiliac joint by tumors significantly compromises chances of a successful surgical outcome. The role of MR in this condition is not yet certain, but it may prove to be the method of choice in view of its excellent depiction of skeletal neo plasms.  相似文献   
93.
This study investigated whether previous contact with mental illness affected the attitudes to mental illness (AMI) of general student nurses in Hong Kong — the contact hypothesis. We employed a quasi-experimental design. We compared the attitudes to mental illness of students who had previous contact with mental illness through having taken a psychiatric secondment with those who had not taken a psychiatric secondment. Also, we compared the AMI of: students who had taken other courses related to mental illness with those who had not; those who had a family history of mental illness with those who had not; and those who lived with a mentally ill relative with those who did not. We found that previous contact with mental illness had no significant effect on the attitudes to mental illness of the students. In other words our findings do not support the contact hypothesis. Our sample expressed positive general attitudes to mental illness when presented with general issues about mental illness. However, their attitudes were less positive when presented with specific issues about mental illness that might impinge upon their daily lives. We discuss the implications of these findings for mental health nursing practice, education and research.  相似文献   
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95.
: A rising prostate specific antigen (PSA) following treatment for adenocarcinoma of the prostate indicates eventual clinical failure, but the rate of rise can be quite different from patient to patient, as can the pattern of clinical failure. We sought to determine whether the rate of PSA rise could differentiate future local versus metastatistic failure.

: Two thousand six hundred sixty-seven PSA values from 400 patients treated with radiotherapy for localized adenocarcinoma of the prostate were analyzed with respect to PSA patterns and clinical outcome. Patients had received no hormonal therapy or prostate surgey and had ?4 PSA values post-treatment PSA rate of rise, determined by the slope of the natural log, was classified as gradual (< 0.69 log (ng/ml)/year, or doubling time (DT) > 1 year), moderate (0.69-1.4 log (ng/ml)/year, or DT 6 months-1 year), or rapid [>1.4 log (ng/ml)/year, or DT < 6 months].

: SIxty-one percent of patients had non-rising PSA following treatment; 25% of patients with rising PSA developed clinical failure, and 93% of patients with clinical failure had rising PSA. The rate of rise discerned different clinical failure patterns. Local failure occurred in 23% of patients with moderate rate of rise versus 7% with gradual rise (p = 0.0001). Metastatic disease developed in 46% of those with rapid versus 8% with moderate rise (p < 0.0001). By multivariate analysis, in addition to rate of rise, PSA nadir and rate of decline predicted local failure; those with post-treatment nadir of 1–4 ng/ml were five times more likely to experience local failure than nadir < 1 ng/ml (p = 0.0002). Rapid rate of rise was the most significant independent predictor of metastastic failure.

: The rate of PSA rise following definitive radiotherapy can predict clinical failure patterns, with a rapidly rising PSA indicating metastatic recurrence and moderately rising PSA local recurrence. This information could potentially dirent therapy; if the rise predicts metastatic failure hormonal therapy could be cosidereed, while aggressive salvage therapy may benefit subclinical local recurrence identified by a moderate rate of PSA rise.  相似文献   

96.
Significant advances in understanding of P2X purinoceptor pharmacology have been made in the last few years. The limitations of nucleotide agonists as drug tools have now been amply demonstrated. Fortunately, inhibitors of the degrading ecto-ATPase enzymes are becoming available and it has become apparent that the complete removal of all divalent cations can be used experimentally in some systems to prevent nucleotide breakdown. Despite these issues, convincing evidence for P2X receptor heterogeneity, from data with agonists, has recently been reported.A number of new antagonists at P2X purinoceptors have also recently been described which to some degree appear to be more specific and useful than earlier antagonists like suramin. It is now apparent that suramin is a poor antagonist of ATP in many tissues because it potently inhibits ATPase activity at similar concentrations to those at which it blocks the P2X purinoceptor.Advances in the use of radiolabelled nucleotides as radioligands for binding studies has allowed the demonstration of P2X purinoceptors in a variety of tissues throughout the body including the brain. These studies have also provided evidence for receptor heterogeneity. Excitingly, two P2X purinoceptor genes have been cloned but operational studies suggest that more than two types exist. The cloning studies have also demonstrated a unique structure for the P2X purinoceptor which differentiates it from all other ligand-gated ion channel receptors. Further studies on P2X purinoceptor operation and structure are needed to help resolve controversies alluded to regarding the characterization and classification of nucleotide receptors. Hopefully such studies will also lead to a better understanding of the physiological and pathological importance of ATP and its activation of P2X purinoceptors. This will require the identification of better drug tools, in particular antagonists which may also provide the basis for novel therapeutic agents.  相似文献   
97.
OBJECTIVE: This article examines the success of mini-dental implants (MDI'S) by assessing four subjective measures of patient satisfaction for MDI's in the edentulous maxilla and mandible: comfort, retention, chewing ability and speaking ability. Success rates, surgical techniques, and financial advantages of the MDI's are reviewed. STUDY DESIGN: Thirty consecutive patients received four MDI's between the mental foramen of the mandible from 9/18/2003 to 10/22/2004. Questionnaires were sent to all thirty patients an average of 5 months postoperatively. The patients ranked comfort, retention, chewing ability, and speaking ability from 1 to 10 (1=poor and 10=excellent). RESULTS: A total of 116 MDI's were placed in 13 months and 113 remain stable for a 97.4% implant success rate. Pre-operatively patients rated their retention at 1.7+/-0.42 and post-operatively at 9.6+/-0.37, for a difference of 7.9 (p=3.6-19). Comfort was the next greatest improvement, with a pre-operative rating of 2.2+/-0.63 and a post-operative rating of 9.4+/-0.45, for a difference of 7.2 (p=3.5-15). Chewing ability also improved, with a difference of 7.0 (p=2.9e-16). In the final category of speaking ability, the pre-operative to post-operative difference was 3.2 (p=1.1e-5). CONCLUSION: MDI's are a highly successful implant option for patients with poor tolerance to maxillary and mandibular prosthesis. The implants are relatively affordable and overall patient satisfaction is excellent.  相似文献   
98.
99.
A 20-day treatment with LF15-0195, a deoxyspergualine analog, induced long-term heart allograft survival in the rat without signs of chronic rejection. LF15-0195-treated recipients did not develop an anti-donor alloantibody response. Analysis of graft-infiltrating cells, IL10, TNFalpha, IFNgamma mRNA and iNOS protein expression in allografts, 5 days after transplantation, showed that they were markedly decreased in allografts from LF15-0195-treated recipients compared with allografts from untreated recipients. Surprisingly, spleen T cells from LF15-0195 recipients, 5days after grafting, were able to proliferate strongly in vitro, when stimulated with donor cells, but had reduced mRNA expression for IFNy compared with spleen T cells from untreated graft recipients. Furthermore, when T cells from naive animals were stimulated in vitro, using anti-CD3 and anti-CD28, LF15-0195 also increased T-cell proliferation in a dose-dependent fashion: however, these cells expressed less of the Th1 -related cytokines, IFNgamma and IL2, compared with untreated cells, suggesting that LF15-0195 could act on T-cell differentiation. In conclusion, we show here that a short-term treatment with LF15-0195 induced long-term allograft tolerance, decreasing the in situ anti-donor response, and we illustrate evidence for the development of regulatory mechanisms.  相似文献   
100.
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