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991.
OBJECTIVES: To investigate the specific complaints of physicians and technicians performing obstetric and gynecological ultrasound. METHODS: This was a cross-sectional retrospective survey. Questionnaires were distributed to members of the Israeli Society of Gynecological Ultrasound, including questions on gender and profession, number and type of scans performed, pain related to profession and any therapy undergone. Statistical analysis included chi-square or Fisher's exact test, Student's t-test, Pearson's correlation coefficient and logistic regression. RESULTS: Joint pain was reported by 51.7% (30/58) of the technicians compared with 25.3% (19/75) of the physicians (P = 0.002). It was more common in females than in males (P = 0.05) and it was more common among those who performed transabdominal sonography more frequently than they did transvaginal sonography (P = 0.004). There was a significant association between performing transabdominal ultrasound and back pain (P = 0.05). Although females reported pain more frequently, the rate of surgical procedures was higher among males (P < 0.05). CONCLUSIONS: A technician is 3.5 times more likely to report joint pain than is a physician. Transabdominal sonography is a risk for both joint and back pain. There may be gender differences in pain perception.  相似文献   
992.
993.
Positron emission tomography was performed on six patients with Rett syndrome to investigate cerebral blood flow and oxygen metabolism, and the results were compared with the concurrent clinical status of the patients. The cerebral metabolic rate of oxygen (CMRO2) was low in five patients, and oxygen extraction fraction was low in four patients; both had a tendency to decline with advancing age. Although the cause is unknown, it is suggested that impaired oxidative metabolism exists in Rett syndrome. An analysis of the distribution among brain regions showed that the ratios of values for the frontal cortex to those for the temporal cortex for both cerebral blood flow and CMRO2 were lower than those for the controls, which may indicate the loss of hyperfrontality in Rett syndrome.  相似文献   
994.
995.
Localization of ferritin using a pre-embedding diffusion technique and an indirect localization sequence has been made in 34 cases of human liver under normal and several pathological conditions. With light microscopic observation, positive immuno-staining for ferritin was demonstrated as diffuse deposits in the hepatocytes and Kupffer cells. Intensity of the positive immuno-staining for ferritin in these cells appeared to roughly coincide with serum ferritin levels of each patient, but showed no disease specificity, although hepatoma cells contained weak deposits or were negative from immuno-staining for ferritin. With electron microscopic studies, intracellular antigen was well preserved in the hepatocytes and Kupffer cells in most cases with the positive immuno-staining for ferritin being observed in cytosol and a few cisternae of rough endoplasmic reticulum. Content of the positive immuno-staining for ferritin differed considerably from one case to another and one cell to another even in the same case. There was no immuno-staining for ferritin in hemosiderin pigment, lysosome, most of rough endoplasmic reticulum, Golgi complexes, and nucleus in both cells.  相似文献   
996.
The authors performed a prospective study of the value of ultrasonography (US) and US-guided fine-needle aspiration cytology (FNAC) for assessment of N0 lesions in the neck. Preoperative US was performed in 107 patients with squamous cell carcinoma of the head and neck, who underwent 132 elective neck dissections. During the US examination of the last 54 patients, who underwent 70 elective neck dissections, US-guided FNAC was performed. US alone was found to be an unreliable method for detecting occult lymph node metastasis; the accuracy never exceeded 70% (93 of 132), with a sensitivity of 60% (32 of 53) and a specificity of 77% (61 of 79). In contrast, US-guided FNAC had an accuracy of 89% (62 of 70), a sensitivity of 76% (25 of 33), and a specificity of 100% (37 of 37). Because of the high sensitivity and specificity of US-guided FNAC for the assessment of the N0 neck, this modality may play an important role in directing treatment of these patients in the future.  相似文献   
997.
Calcifying odontogenic cyst (COC) has shown to be of extensive diversity in its clinical and histopathological features, as well as in its biological behavior. In this report, a rare case is described of ameloblastoma ex COC (dentinogenic ghost cell tumor) and the relevant literature is briefly reviewed.  相似文献   
998.
999.
Aims Cardiovascular disease (CVD) is a major complication of Type 2 diabetes mellitus. The renin‐angiotensin system (RAS) and nitric oxide production are both important regulators of vascular function and blood pressure. Genes encoding proteins involved in these pathways are candidates for a contribution to CVD in diabetic patients. We have investigated variants of the angiotensinogen (AGT), angiotensin converting enzyme (ACE), angiotensin type 1 receptor (AT1R) and endothelial nitric oxide synthase (NOS3) genes for association with subclinical measures of CVD in families with Type 2 diabetes mellitus (T2DM). Methods Atherosclerosis was measured by carotid intima‐media thickness and calcification of the carotid and coronary arteries in 620 European Americans and 117 African Americans in the Diabetes Heart Study. Because of the role of these systems in blood pressure regulation, blood pressure was also investigated. Results Compelling evidence of association was not detected with any of the SNPs with any outcome measures after adjustments for covariates despite sufficient power to detect relatively small differences in traits for specific genotype combinations. Conclusions Genetic variation of the RAS and NOS3 genes do not appear to strongly influence subclinical cardiovascular disease or blood pressure in this diabetic population.  相似文献   
1000.
INTRODUCTION: Concern about the potential detrimental side-effects of beta-blockade on pulmonary function often dissuades against their perioperative use in patients undergoing major arterial surgery (especially in those with chronic obstructive pulmonary disease (COPD)). In this study we aimed to establish prospectively the clinical relevance of these concerns. METHODS: After ethics committee approval and individual informed consent, the pulmonary function of twenty patients (mean age 68.7 years (range 43-82), 11 males) scheduled to undergo non-emergency major vascular surgery was studied by recording symptoms and spirometry before and after institution of effective beta-blockade. Fifteen patients (75%) had significant smoking histories (mean pack years/patient=50), while 12 (60%) had COPD. RESULTS: All patients tolerated effective beta-blockade satisfactorily without developing either subjective deterioration in symptoms or significant change on spirometry. The mean change in FEV1 following adequate beta-blockade was 0.05+/-0.24 liters (95% CI -0.06 to +1.61), p=0.35, giving a mean percentage change of 3.18%+/-11.66 (95% CI -2.26 to 8.62). CONCLUSIONS: Previously held concerns about worsening pulmonary function through the short-term use of beta-blockers should not dissuade their perioperative usage in patients with peripheral vascular disease. Furthermore, the accuracy of pulmonary function tests in preoperative assessment and risk stratification also appears unaffected by this therapy.  相似文献   
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