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101.
The aim of this paper was to perform a systematic review of the pathogenesis of medication‐induced salivary gland dysfunction (MISGD). Review of the identified papers was based on the standards regarding the methodology for systematic reviews set forth by the World Workshop on Oral Medicine IV and the PRISMA statement. Eligible papers were assessed for both the degree and strength of relevance to the pathogenesis of MISGD as well as on the appropriateness of the study design and sample size. A total of 99 papers were retained for the final analysis. MISGD in human studies was generally reported as xerostomia (the sensation of oral dryness) without measurements of salivary secretion rate. Medications may act on the central nervous system (CNS) and/or at the neuroglandular junction on muscarinic, α‐and β‐adrenergic receptors and certain peptidergic receptors. The types of medications that were most commonly implicated for inducing salivary gland dysfunction were those acting on the nervous, cardiovascular, genitourinary, musculoskeletal, respiratory, and alimentary systems. Although many medications may affect the salivary flow rate and composition, most of the studies considered only xerostomia. Thus, further human studies are necessary to improve our understanding of the association between MISGD and the underlying pathophysiology.  相似文献   
102.
Stress fractures amongst military recruits are limited to the lower extremities; yet involvement of the shaft of the femur is unusual. Seven such cases in a series of 352 stress fractures are presented. The importance of early recognition and management is emphasized with a view to prevent bony disruption in an otherwise easily treatable condition.KEY WORDS: Fractures stress, Femoral fractures  相似文献   
103.
The BRCA1 tumor suppressor gene and the HER-2/neu oncogene are located in close proximity on the long arm of chromosome 17 (17q11-21). Absence of BRCA1 or functional overexpression of the HER-2/neu gene presumably contributes to the somatic phenotype of breast cancer in premenopausal women, characterized by unfavorable prognostic features such as high tumor grade, hormone receptor negativity, and high proliferation rate. To examine whether amplification of HER-2/neu contributes to the aggressive biology of BRCA1-associated tumors, we have performed fluorescence in situ hybridization on formalin-fixed paraffin-embedded breast tumor tissue sections from 53 BRCA1 mutation carriers and 41 randomly selected, age-matched sporadic breast cancer cases. Although BRCA1-associated and sporadic tumors were equally likely (19% versus 22%) to exhibit HER-2/neu amplification [defined as a ratio of HER-2/neu copies to chromosome 17 centromere (CEP17) copies > or = 2], 6 (15%) of the sporadic tumors were highly amplified (defined as a ratio greater-than-or-equal 5) versus none of the BRCA1-associated tumors (P = 0.048). HER-2 protein overexpression as measured by immunohistochemical analysis was not observed among the BRCA1-associated cases (P = 0.042). Four of 21 (19%) sporadic tumors exhibited strong membranous staining of HER-2 (intensity level of 3+) as compared with 0 of 39 BRCA1-associated tumors. Our data suggest that a germ-line mutation in the BRCA1 tumor suppressor gene is associated with a significantly lower level of HER-2/neu amplification. Thus, it is possible that BRCA1-associated and HER-2/neu-highly amplified tumors progress through distinct molecular pathways, and the aggressive pathological features of BRCA1-associated tumors appear unrelated to amplification of the adjacent HER-2/neu oncogene.  相似文献   
104.
A volumetric approach to quantitative single-energy computed tomography (CT) of the spine for trabecular bone evaluation was compared with the accepted single-section method in 32 thoracic and lumbar vertebral bodies from six cadaveric specimens. Both 5-mm and 10-mm contiguous section sequences afforded greater sample volumes, mean mineral equivalent values, and precision than did the single midplane section technique. These findings can be explained by inhomogeneous trabecular distribution, differential bone resorption rates for various cancellous regions, and nonuniform deposition of marrow fat. Scoliosis may modify the net influence of these factors owing to altered biomechanical forces. Although the single-section method affords optimal sensitivity to early or subtle alterations in vertebral trabecular bone density, it may misrepresent the status of the total cancellous volume. Because three-dimensional histographic analysis includes structurally important peripheral trabeculae in determinations of mean mineral equivalent values, it may more accurately reflect vertebral body strength and risk of compression fracture.  相似文献   
105.
Sternocostoclavicular hyperostosis: a review and report of 11 cases   总被引:1,自引:0,他引:1  
Sternocostoclavicular hyperostosis is a benign ossifying diathesis of unknown etiology characterized by hyperostosis and soft-tissue ossification between the clavicles, anterior portion of the upper ribs, and manubrium, with variable hyperostosis or ankylosis in the spine and sacroiliac joints. Our cumulative experience with 11 cases is reported, with emphasis on radiographic features of the condition. Scintigraphic results in five patients and computed tomographic findings in one patient are presented. A review of the literature and our own material indicates that sternocostoclavicular hyperostosis may be more common than has been previously recognized.  相似文献   
106.
107.
Sartoris  DJ; Clopton  P; Nemcek  A; Dowd  C; Resnick  D 《Radiology》1986,160(2):479-483
The radiographic patterns of vertebral-body collapse and/or endplate deformity were examined in 99 autopsy specimens of the thoracolumbar spine with benign and malignant disease. Angling of endplates was found to be highly predictive of underlying malignancy, whereas concavity was more suggestive of benign disease, for both individual vertebral bodies and intact spines (P less than .001). Diffuse-concave, diffuse-angled, and focal-angled patterns were more useful (P less than .001) than the focal-concave pattern (P = .07) in distinguishing between benign and malignant disease for superior endplates, whereas all were equally useful (P less than .025) in inferior endplates. Condition of the adjacent disks, location within the spine, and position of the apex of collapse were not predictive. Although these results and subsequent blinded testing suggest that reliable distinction between benign and malignant vertebral collapse is possible, extrapolation to clinical practice may be inappropriate because of population bias in the study and differences in radiographic quality between autopsy specimens and live subjects.  相似文献   
108.
Auditory P300 in borderline personality disorder and schizophrenia   总被引:5,自引:0,他引:5  
Using three sets of clinical criteria to define borderline personality disorder (BPD), P300 (P3) and other long-latency auditory event-related electroencephalographic potentials were measured in 22 subjects with BPD, 32 subjects with other personality disorders, 29 schizophrenics, 22 depressives, and 74 volunteer controls. The patients with BPD were found to differ from patients with nonborderline personality disorders, having a longer P3 latency and smaller P3 amplitude. Long-latency event-related potentials were similar in the BPD and schizophrenic groups and did not differentiate patients with BPD with a concurrent diagnosis of schizotypal personality disorder from those without schizotypal personality disorder. The P3 latency and amplitude changes distinguished the BPD and schizophrenic groups from normal controls, those with major depressive disorder, and those with nonborderline personality disorders. These findings suggest that though some patients with BPD may have depressive symptomatology, they share with schizophrenics a dysfunction of auditory neurointegration.  相似文献   
109.
Pathria  M; Sartoris  DJ; Resnick  D 《Radiology》1987,164(1):227-230
Sensitivity and specificity of lumbar spine radiography in the assessment of facet joint osteoarthritis were evaluated, with computed tomography (CT) as the standard. Two independent radiologists used a four-point scale to blindly grade facet joint osteoarthritis on oblique radiographs and transaxial CT scans obtained within an 8-month period in 50 consecutive patients with pain in the lower back. The L-3 to L-4, L-4 to L-5, and L-5 to S-1 facet joints were evaluated, and 68% appeared abnormal on CT scans, with 28% exhibiting moderate or severe disease. Interobserver agreement was high for conventional radiography (perfect agreement in 57% and agreement to within one grade in 39%) and still higher for CT (perfect in 63% and to within one grade in 35%). Receiver operating characteristic curve analysis indicated that oblique radiography was most accurate (55% sensitivity, 69% specificity) in distinguishing the presence from the absence of disease; in distinguishing absent or mild from moderate or severe disease, the specificity of oblique radiography was higher, at 94%, but its sensitivity was much lower, at 23%. Conventional radiography is a useful technique in screening for facet joint osteoarthritis but is insensitive compared with CT.  相似文献   
110.
Medical schools put little emphasis upon education on public health, even though public health has played an important role in this century. One way to harness its benefit in order to improve global health in the 21st century is to globally share lectures on public health through the Internet. We have developed the Supercourse comprising of web-based learning modules on epidemiology in a standardized format with the size of each web page less than 10 kilobytes. A cross-sectional observational study was conducted to investigate the association of the perception of the access speed to Web-based lectures by teachers with their perception of lecture quality. There were 223 teachers who rated the lectures: 72% were from North America or Western Europe, 40% had taught epidemiology, and 14% reported that the speed of access was slow. Odds ratio of above-average rating among those who reported that the speed of access was fast relative to those who reported that the speed of access was slow was 4.25 (2.03-8.91; P = 0.001). The odds ratios were similar and significant after taking into account several other factors, including the variation of rating across lectures, region, and experiences in teaching epidemiology. The results indicate that the perception of the quality of Web-based lectures is related to the speed of access to a web page. The speed of access may be as important, if not more important, as the content itself. This suggests that, to share educational materials on the Web globally for teachers, one must consider not only the content, but also how people at local sites gain access to the Internet.  相似文献   
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