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121.
BACKGROUND: Internists in all settings see many patients with skin conditions. Thus, their education in dermatology is important. Information on which areas of dermatology are most commonly seen in internal medicine practices is necessary for designing effective educational programs on skin disease. OBJECTIVE: To determine what types of dermatologic problems internists most commonly diagnose. METHODS: National Ambulatory Medical Care Survey data from 1990 to 1994 were analyzed for dermatologic diagnoses. Physicians specializing in internal medicine and all its subspecialties were compared with dermatologists and with other physicians. RESULTS: The most common skin disorders diagnosed by internists were dermatitis (15.8% of all diagnoses) and bacterial skin infections (14.0% of all diagnoses). Combined, bacterial, fungal, and viral infections included 28.3% of the most common dermatologic diagnoses made by internists. The top 10 most common diagnoses accounted for 57.9% of all skin-related diagnoses and the top 20 most common diagnoses accounted for 72.8%. Internists were more likely to see patients for bacterial skin infections, herpes infection, exanthem, urticaria, and insect bites while dermatologists more commonly saw patients for actinic and seborrheic keratoses, warts, benign and malignant skin tumors, and psoriasis. CONCLUSIONS: The most common dermatologic diseases diagnosed by internists differ considerably from those diagnosed by dermatologists. Because dermatologists do much of the dermatology teaching of internal medicine residents, it is important to recognize these differences to place emphasis on the proper areas of study. Some common or serious skin conditions not often diagnosed by internists such as psoriasis and melanoma also deserve attention in internal medicine training programs.  相似文献   
122.
To study the effect of stroke on the quality of life in younger adults, 199 patients 17-49 years of age who had sustained a first stroke between 1.11.92 and 31.10.93 were followed up. They were interviewed by telephone at 3, 6, 12 and 24 months after the event. 2 died during the first year of follow-up, and 8 had recurrent strokes. After 2 years, 8 additional patients had died and 4 had sustained recurrent events. Gradual improvement was reported within all age groups and in all areas. During the 3-6 months period, a mean of 4% improvement occurred in functional capability, 15% in social and recreational activity and 8% in return-to-work. The 6-12 month period showed an increase of 3% in improvement in mean functional capability, 10% in social and recreational activity and 2% in return-to-work. 1 year after the stroke 27% remained with moderate to severe disability, but over 86% were functionally independent in their daily living activities. There were no significant changes during the second year of follow-up in these statistics. 67% of those employed prior to their stroke returned to work and approximately 70% reported a return to prestroke social and recreational activity. These results demonstrate that the relatively high recovery rate and functional improvement during a year of follow-up were not accompanied by similar rates of improvement in employment and in social integration. They indicate the need for increased emphasis on long-term psychosocial rehabilitation services within the community.  相似文献   
123.
An approach to evaluating the accuracy of DXplain.   总被引:1,自引:0,他引:1  
DXplain is a computer-based decision support system which generates a differential diagnosis (ddx) from a given list of clinical manifestations (Barnett et al., J. Am. Med. Assoc. 258 (1987) 67-74). An approach was developed to evaluate the accuracy of the ddx's produced by DXplain. The first step involves the collection of 65 benchmark cases drawn from a variety of sources and authors. Despite their diverse origins, the cases share in common that they are all clinical cases upon which a consulting physician might be asked to produce a differential. This helps to ensure that the evaluation of the system will be done in an environment similar to that in which the system is actually used. In the second step, all cases are reviewed by five board-certified physicians (experts) as well as DXplain. For each case, the evaluators (experts and DXplain) produce a rank-ordered ddx list along with an indication of how strongly each disease was felt to be supported by the case findings. A scoring technique was devised which rewards concordance with the gold standard: a consensus of the evaluators' ddx lists. Each evaluator receives a score which is proportional to the degree of agreement achieved with the consensus on the ddx submitted. Preliminary results on a trial evaluation of 46 cases indicate that DXplain, on average, did well in agreeing with the consensus. Agreement was achieved both in regard to the specific diagnoses listed in the ddx and the degree to which the diseases were felt to be supported by the case findings. A discussion of some important issues in the evaluation of knowledge-based systems is undertaken.  相似文献   
124.
Book review     
The Annals of Regional Science -  相似文献   
125.
BACKGROUND: In 1982, the National Surgical Adjuvant Breast and Bowel Project initiated a randomized, double-blinded, placebo-controlled trial (B-14) to determine the effectiveness of adjuvant tamoxifen therapy in patients with primary operable breast cancer who had estrogen receptor-positive tumors and no axillary lymph node involvement. The findings indicated that tamoxifen therapy provided substantial benefit to patients with early stage disease. However, questions arose about how long the observed benefit would persist, about the duration of therapy necessary to maintain maximum benefit, and about the nature and severity of adverse effects from prolonged treatment. PURPOSE: We evaluated the outcome of patients in the B-14 trial through 10 years of follow-up. In addition, the effects of 5 years versus more than 5 years of tamoxifen therapy were compared. METHODS: In the trial, patients were initially assigned to receive either tamoxifen at 20 mg/day (n = 1404) or placebo (n = 1414). Tamoxifen-treated patients who remained disease free after 5 years of therapy were then reassigned to receive either another 5 years of tamoxifen (n = 322) or 5 years of placebo (n = 321). After the study began, another group of patients who met the same protocol eligibility requirements as the randomly assigned patients were registered to receive tamoxifen (n = 1211). Registered patients who were disease free after 5 years of treatment were also randomly assigned to another 5 years of tamoxifen (n = 261) or to 5 years of placebo (n = 249). To compare 5 years with more than 5 years of tamoxifen therapy, data relating to all patients reassigned to an additional 5 years of the drug were combined. Patients who were not reassigned to either tamoxifen or placebo continued to be followed in the study. Survival, disease-free survival, and distant disease-free survival (relating to failure at distant sites) were estimated by use of the Kaplan-Meier method; differences between the treatment groups were assessed by use of the logrank test. The relative risks of failure (with 95% confidence intervals [CIs]) were determined by use of the Cox proportional hazards model. Reported P values are two-sided. RESULTS: Through 10 years of follow-up, a significant advantage in disease-free survival (69% versus 57%, P < .0001; relative risk = 0.66; 95% CI = 0.58-0.74), distant disease-free survival (76% versus 67%, P < .0001; relative risk = 0.70; 95% CI = 0.61-0.81), and survival (80% versus 76%, P = .02; relative risk = 0.84; 95% CI = 0.71-0.99) was found for patients in the group first assigned to receive tamoxifen. The survival benefit extended to those 49 years of age or younger and to those 50 years of age or older. Tamoxifen therapy was associated with a 37% reduction in the incidence of contralateral (opposite) breast cancer (P = .007). Through 4 years after the reassignment of tamoxifen-treated patients to either continued-therapy or placebo groups, advantages in disease-free survival (92% versus 86%, P = .003) and distant disease-free survival (96% versus 90%, P = .01) were found for those who discontinued tamoxifen treatment. Survival was 96% for those who discontinued tamoxifen compared with 94% for those who continued tamoxifen treatment (P = .08). A higher incidence of thromboembolic events was seen in tamoxifen-treated patients (through 5 years, 1.7% versus 0.4%). Except for endometrial cancer, the incidence of second cancers was not increased with tamoxifen therapy. CONCLUSIONS AND IMPLICATIONS: The benefit from 5 years of tamoxifen therapy persists through 10 years of follow-up. No additional advantage is obtained from continuing tamoxifen therapy for more than 5 years.  相似文献   
126.
Electric and magnetic dipole transition probabilities, fluorescence branching ratios, integrated emission coefficients, fluorescence efficiencies, and fluorescence lifetimes are determined for the lower lying states of Pr:LaCl3 using the Judd-Ofelt theory and calculated multiphonon emission probabilities. The results are used to characterize demonstrated mid-IR laser transitions and predict new potential mid-IR laser transitions in Pr:LaCl3  相似文献   
127.
Fluorescence microscopic methods have been used to characterize the cell cycle of Bacillus subtilis at four different growth rates. The data obtained have been used to derive models for cell cycle progression. Like that of Escherichia coli, the period required by B. subtilis for chromosome replication at 37 degrees C was found to be fairly constant (although a little longer, at about 55 min), as was the cell mass at initiation of DNA replication. The cell cycle of B. subtilis differed from that of E. coli in that changes in growth rate affected the average cell length but not the width and also in the relative variability of period between termination of DNA replication and septation. Overall movement of the nucleoid was found to occur smoothly, as in E. coli, but other aspects of nucleoid behavior were consistent with an underlying active partitioning machinery. The models for cell cycle progression in B. subtilis should facilitate the interpretation of data obtained from the recently introduced cytological methods for imaging the assembly and movement of proteins involved in cell cycle dynamics.  相似文献   
128.
Participants segmented and shifted a sequence of letters from a source word to a target word and then named the product aloud. Morphemic and nonmorphemic letter sequences (e.g., EN) from phonemically matched words such as HARDEN and GARDEN were compared. In 4 experiments, naming latencies were faster for morphemic sequences than their nonmorphemic controls in both English, in which the morphemic status of the shifted sequence was varied and sequences were appended after the base morpheme (linearly concatenated), and in Hebrew, in which morphological transparency of the root (base morpheme) was varied and 1 morpheme was infixed inside the other (nonconcatenative) so that the phonological and orthographic integrity of the morphemic constituents was disrupted. Moreover, the likelihood with which both affixes and bases combine to form words influenced segment shifting times. In conclusion, skilled readers are sensitive to the morphological components of words whether or not they form contiguous orthographic or phonological units. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
129.
130.
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