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91.
The American College of Prosthodontists (ACP) has developed a classification system for partial edentulism based on diagnostic findings. This classification system is similar to the classification system for complete edentulism previously developed by the ACP. These guidelines are intended to help practitioners determine appropriate treatments for their patients. Four categories of partial edentulism are defined, Class I to Class IV, with Class I representing an uncomplicated clinical situation and class IV representing a complex clinical situation. Each class is differentiated by specific diagnostic criteria. This system is designed for use by dental professionals involved in the diagnosis and treatment of partially edentulous patients. Potential benefits of the system include (1) improved intraoperator consistency, (2) improved professional communication, (3) insurance reimbursement commensurate with complexity of care, (4) improved screening tool for dental school admission clinics, (5) standardized criteria for outcomes assessment and research, (6) enhanced diagnostic consistency, and (7) simplified aid in the decision to refer a patient.  相似文献   
92.
5-S-cysteinyldopa concentrations were determined by high-pressure liquid chromatography and electrochemical detection in plasma from normally pigmented patients and patients with oculocutaneous albinism, both tyrosinase-positive and tyrosinase-negative. The plasma 5-S-cysteinyldopa concentrations were similar in all three groups, suggesting that 5-S-cysteinyldopa can be produced by mechanisms which do not involve tyrosinase.  相似文献   
93.
OBJECTIVE: To assess the relationship between early laboratory parameters, disease severity, type of management (surgical or conservative) and outcome in necrotizing enterocolitis (NEC). STUDY DESIGN: Retrospective collection and analysis of data from infants treated in a single tertiary care center (1980 to 2002). Data were collected on disease severity (Bell stage), birth weight (BW), gestational age (GA) and pre-intervention laboratory parameters (leukocyte and platelet counts, hemoglobin, lactate, C-reactive protein). RESULTS: Data from 128 infants were sufficient for analysis. Factors significantly associated with survival were Bell stage (P<0.05), lactate (P<0.05), BW and GA (P<0.01, P<0.001, respectively). From receiver operating characteristics curves, the highest predictive value resulted from a score with 0 to 8 points combining BW, Bell stage, lactate and platelet count (P<0.001). At a cutoff level of 4.5 sensitivity and specificity for predicting survival were 0.71 and 0.72, respectively. CONCLUSION: Some single parameters were associated with poor outcome in NEC. Optimal risk stratification was achieved by combining several parameters in a score.  相似文献   
94.
95.
In response to interest by dental students and patient needs, an elective program in implant dentistry was started at the University of Detroit Mercy School of Dentistry (UDM) in the summer of 1994. The 1-year program is offered to a group of 10 senior students out of a class of 72. Implant treatment is provided to selected edentulous and partially edentulous patients. Predoctoral students participate in diagnosis and treatment planning, assist in surgical placement, and perform the prosthodontic procedures. A survey was sent to 160 UDM graduates, and 90 responded. Out of the 90 respondents, 35% had participated in the elective implant program and 65% had not. A Pearson correlation matrix was used to analyze their responses. A stronger positive correlation with offering and restoring implants was seen in graduates who had completed the elective program in implant dentistry.  相似文献   
96.
Ultrasonography is frequently useful in the differential diagnosis of ectopic pregnancy. It proved to be valuable in the diagnosis of an interstitial ectopic pregnancy.  相似文献   
97.
A pilot study was conducted into the forces imposed on an instrumented, hand-held frame by two groups of elderly females. One group had been identified as having idiopathic gait disorders, and each subject had a history of falling for no apparent clinical reason. Tests were carried out to compare the responses of the two groups to single-leg-stance balance maneuvers. Results suggested that the "fallers" required greater support during single-leg stance. It was inferred that the fallers displaced their body mass more laterally during this procedure than was the case with the control group. Fallers applied greater forces to the frame with their eyes closed than with their eyes open; the control group did not show significant differences in this respect. These findings may help to define some of the biomechanical problems associated with idiopathic gait disorders.  相似文献   
98.
Twenty-one cases of vulvar Paget's disease were studied to assess possible prognostic indicators, including presence and depth of invasion, status of resection margins, tumor DNA cell content, and immunoreactivity for p53 and estrogen receptor proteins. Immunostaining for cytokeratin 7 (CK7), cytokeratin 20 (CK20), and gross cystic disease fluid protein-15 (GCDFP) were also performed. Patients were 45 to 82 years of age (mean, 66.9 years). Ten of 21 patients (47.6%) had invasive Paget's disease. Dermal invasion was < or = 1 mm in 7 of 10 cases and 2 mm, 3 mm, and 8 mm in the remaining three invasive tumors. Of the seven patients with minimally invasive Paget's disease (< or = 1 mm depth of invasion), five are alive with no evidence of disease, one died of an unrelated illness, and one is alive with biopsy-proven in situ Paget's disease, having refused operative treatment. Of the three patients with more than minimally invasive Paget's disease (> 1 mm), all had nodal metastases; one patient is alive with no evidence of disease, one died of undertermined causes, and one died of metastatic Paget's disease. The remaining 11 patients had Paget's disease confined to the epidermis and its adnexal structures. Seven of these patients were alive at last follow-up with no evidence of disease. Of the remaining four patients, one died of metastatic cervical cancer, one died of metastatic bladder cancer, one died of an unrelated illness, and one patient is alive with biopsy-proven in situ Paget's disease and awaiting operative treatment. Twenty of the 21 cases represented primary vulvar Paget's disease while one represented possible local spread from a cervical adenocarcinoma. The immunoprofiles were GCDFP+/CK7+/CK20- in 14 cases, GCDFP+/CK7+/CK20+ in 4 cases, and GCDFP-/CK7+/CK20- in 2 cases. All tumors were estrogen receptor-negative. Immunostaining for p53 was positive in 16 tumors and negative in four tumors. Seven of 12 (58%) patients with positive margins experienced local recurrence of Paget's disease, while the disease recurred in 1 of 4 patients with negative margins. Recurrence was observed in 3 of 5 patients with diploid tumors and in 4 of 10 patients with aneuploid tumors. Neither of these differences is statistically significant. This study supports the recognition of a category of minimally invasive vulvar Paget's disease that has a low risk of distant metastasis and death caused by disease. Status of surgical resection margins, tumor cell DNA ploidy, estrogen receptor expression, and p53 immunoreactivity are not predictive of local recurrence.  相似文献   
99.
Lee S  Simpson M  Nimmo M  Xu Z 《Carcinogenesis》2004,25(10):1879-1885
Zinc has been shown to be accumulated in N-methyl-N-nitrosourea (MNU)-induced rat mammary tumors. Zinc is required for cell proliferation and tumorigenesis is characterized by dysregulation of cell proliferation. An accumulation of zinc in mammary tumors perhaps indicates a reliance on zinc to sustain tumor growth. Limiting zinc supply by means such as reduced zinc intake should negatively modulate mammary tumorigenesis. Our objective was to determine the effects of zinc status on MNU-induced mammary tumorigenesis in sexually mature female rats. Twenty-one-day-old Sprague-Dawley rats were assigned to low-zinc (3 mg zinc/kg diet) or adequate-zinc (12 mg zinc/kg diet) ad libitum or pair-fed control group (n = 25-33 rats/group). On day 50 of age, all rats were intraperitoneally injected with MNU (50 mg/kg body wt) to induce mammary tumorigenesis. Rats were further maintained on their assigned diet until 14 weeks post-MNU injection. Total food intake and overall body weight gain were lower in low-zinc rats than in adequate-zinc ad libitum control rats, but were similar to adequate-zinc pair-fed control rats. Plasma zinc concentration was lower in low-zinc rats than in adequate-zinc ad libitum and pair-fed control rats, confirming moderately low-zinc status in low-zinc rats. Tumor incidence (46 versus 84 and 80%; P < 0.05) and tumor multiplicity (0.8 versus 5.0 and 2.6 tumors/rat; P < 0.05) and tumor number (28 versus 123 and 66 tumors) were reduced in low-zinc rats compared with that in adequate-zinc ad libitum and pair-fed control rats, respectively. Tumor latency in low-zinc and adequate-zinc pair-fed control rats was not significantly different, but was longer than in adequate-zinc ad libitum control rats (P < 0.05), suggesting that reduced food intake associated with low-zinc intake prolonged tumor latency. Tumor burden and size were not affected by zinc intake. Overall, our observations showed that moderately low-zinc status suppressed MNU-induced rat mammary tumorigenesis.  相似文献   
100.
The prerequisites for a change in practice in individual pharmacists, as framed by the Holland-Nimmo practice change model, are discussed. The Holland-Nimmo practice change model comprises three components, all of which must be addressed by a pharmacy's leadership if a change in practice is to be achieved. The first component is the practice environment, which must be conducive to implementation of the new form of practice. The second component is the availability of appropriate training for individual practitioners. The third component is an appropriate set of motivational strategies to be applied by the manager. All three components must be present at the same time; no one or two components by themselves are sufficient. The practice change model is equally applicable to pharmacy department managers in health-system settings and to community pharmacy owners and managers. To maximize the potential for individual pharmacists to change their practice, managers must create an environment conducive to the new form of practice, identify needed learning resources, and motivate practitioners to change.  相似文献   
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