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Basal cell adenocarcinoma (BCA) is an uncommon salivary gland neoplasm. The majority of salivary gland tumors are located in the parotid gland, while only a few involves the minor salivary gland of the oral cavity. Pathological diagnosis is important to differentiate BCA from other neoplasms, as the prognosis of the diseases is significantly different. In this article, we present a 41-year-old-male with BCA involving the upper labial mucosa.  相似文献   
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Objective

To investigate the value of post-traumatic pronator quadratus (PQ) fat pad sign as a reliable predictor of subtle wrist fractures.

Materials and methods

This was a prospective study of 68 patients undergoing X-ray for traumatic wrist injuries and subsequent MRI. The reliability of a positive PQ fat pad sign on X-ray, defined as either raised, interrupted or obliterated, was evaluated in detection of subtle wrist fractures.

Results

Out of 68 patients, 28 had a positive PQ sign without any obvious bony injuries on plain radiographs; of these, the PQ fat pad was obliterated in 11, disrupted in 12, and raised in five cases. Fractures defined as cortical interruption or trabecular fractures were revealed in 13/28 (46 %) patients with a positive PQ sign but only in 7/40 (18 %) patients with a negative sign. With regards to different types of abnormal PQ fat planes, fractures were present in 7/12 patients with a disrupted plane (58 %), 6/11 patients with an obliterated plane (54 %), and none of the patients with a raised plane. The overall sensitivity and specificity of a positive PQ sign in the prediction of occult wrist fractures were 65 and 69 %, respectively.

Conclusions

Our findings indicate that a positive pronator quadratus (PQ) fat pad sign is not a reliable predictor of subtle fractures of the wrist, although we believe that it is a useful radiographic sign in justifying MRI for further clarification of possible joint abnormalities including occult fracture and cortex interruption.  相似文献   
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Our objective was to utilize the standardized patient technique in assessing the ability of primary care physicians to identify and counsel primary prevention for patients at high risk for skin cancer. A secondary goal was to test the feasibility of this technique as a measure of actual physician behaviors in the outpatient setting. We used a convenience sample of 15 primary care physicians. The standardized patient was an 18-year-old woman with skin phototype I. She presented to physicians as needing a general physical examination for a summer lifeguard job at a beach. She stated a family history of skin cancer. Physician performances were rated using a standard checklist completed by the standardized patient following each visit. We found that none of the physicians asked questions specifically related to skin phototype or sun exposure habits such as childhood sunburns. Only 13% asked about mole changes. For counseling, 67% of physicians recommended sunscreen use; only 7% discussed sunscreen types or procedures for effective use. Only 13% counseled other skin protective behaviors. No significant differences by physician gender were found in these areas; however, female physicians counseled more global health behaviors than male physicians (p < or = 0.01). Our pilot data suggest that little skin cancer primary prevention counseling is performed for high-risk patients. The standardized patient technique worked well in obtaining outcome data for physicians' preventive practices.  相似文献   
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Objective

To investigate the in vivo effect of an imbalance between metalloproteinases and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs), in mouse articular cartilage.

Methods

Hind joints of Timp3−/− and wild‐type mice were examined by routine staining and by immunohistochemical analysis using antibodies specific for type X collagen and for the neoepitopes produced on proteolytic cleavage of aggrecan (… VDIPEN and … NVTEGE) and type II collagen. The neoepitope generated on cleavage of type II collagen by collagenases was quantitated in sera by enzyme‐linked immunosorbent assay.

Results

Articular cartilage from Timp3‐knockout animals (ages ≥6 months) showed reduced Safranin O staining and an increase in …VDIPEN content compared with cartilage from heterozygous and wild‐type animals. There was also a slight increase in … NVTEGE content in articular cartilage and menisci of Timp3−/− animals. Chondrocytes showed strong pericellular staining for type II collagen cleavage neoepitopes, particularly in the superficial layer, in knockout mice. Also, there was more type X collagen expression in the superficial zone of articular cartilage, especially around clusters of proliferating chondrocytes, in the knockout mice. More type II collagen cleavage product was found in the serum of Timp3−/− mice compared with wild‐type animals. This increase was significant in 15‐month‐old animals.

Conclusion

These results indicate that TIMP‐3 deficiency results in mild cartilage degradation similar to changes seen in patients with osteoarthritis, suggesting that an imbalance between metalloproteinases and TIMP‐3 may play a pathophysiologic role in the development of this disease.
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