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41.
Women with polycystic ovary syndrome (PCOS) have a clustering of cardiovascular risk factors, such as obesity, lipid abnormalities, impaired glucose tolerance, insulin resistance, and hypertension. Exercise is reported to lower the incidence of cardiac events. The effect of exercise on plasma homocysteine concentrations, an independent cardiovascular risk factor, has not been previously reported in women with PCOS. We examined the effects of exercise on plasma total homocysteine concentrations in young overweight or obese PCOS women [age (mean +/- SD), 30.6 +/- 6.6 yr; body mass index, 35.49 +/- 7.57 kg/m(2)]. Twenty-one women consented to a 6-month exercise program; 12 women (exercisers) adhered to the program, whereas 9 (nonexercisers) did not. In both groups of women, the following parameters were recorded at baseline and 6 months: body mass index, waist-to-hip ratio, and aerobic capacity (maximal oxygen consumption); blood samples were taken after an overnight fast for plasma total homocysteine, insulin, and other biochemical parameters. A significant decrease in plasma total homocysteine concentrations (P < 0.001) and waist-to-hip ratio (P = 0.041) and a significant increase in maximal oxygen consumption (P = 0.019) were recorded at 6 months, compared with baseline in the exercise group. This decrease in homocysteine was not explained by changes in anthropometric or biochemical parameters. In contrast, no significant changes in any of the variables were observed in the nonexercise group. Our study has provided the first evidence that regular exercise significantly lowers plasma homocysteine in young overweight or obese women with PCOS, a group at increased risk of premature atherosclerosis. The precise mechanism by which exercise is associated with a reduction in homocysteine remains to be elucidated.  相似文献   
42.
Chronic orofacial pain of neuropathic origin can present diagnostic and management dilemmas to dental practitioners and also affects the patient's quality of life. Intracranial aneurysms are a potential cause of stroke (e.g. sub‐arachnoid haemorrhage) that is usually associated with, high rates of mortality and morbidity. A patient who had been previously managed for symptoms of temporomandibular joint disorder (TMD) presented with sharp, shooting pain of moderate intensity. It was precipitated by swallowing, and radiated to the right throat, posterior border of the mandible, ear and temporomandibular joint. Clinical and radiological investigations ruled out odontogenic pain, TMD and other more common types of facial pain. Magnetic resonance imaging revealed a 7 × 6 mm aneurysm in the right middle cerebral artery (MCA) which was subsequently surgically clipped. Interestingly, the facial pain resolved after this procedure. Compression of the insular region of the brain innervated by the trigeminal, glossopharyngeal and vagus nerves provides a plausible explanation for the pain reported. To our knowledge, this is the first case of facial neuralgia associated with an aneurysm in the MCA which emphasizes the importance of a multidisciplinary approach in the diagnosis and management of unusual cases of chronic orofacial pain.  相似文献   
43.
44.
This study sought to investigate the left hemisphere deficit hypothesis regarding autism. A group of 15 autistic youngsters between the ages of 8 and 13 years was compared with a group of 15 mentally retarded youngsters matched for age and IQ on a set of measures presumed to be sensitive to neuropsychological dysfunction. The results suggested that this sample of autistic youngsters is best characterized by bilateral neuropsychological involvement, affecting left-hemisphere functioning predominantly but not exclusively. The findings of this and other such studies seem to be somewhat determined by the varied samples and assessments employed in the research. The practice of selecting tests which presumably tap left or right cerebral functions is highly inferential, and warrants concern, particularly when assessing complex cognitive functioning in autistic individuals.  相似文献   
45.
Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.  相似文献   
46.

Introduction

Prostaglandin-2 (PGE-2), one of the products of cyclooxygenase-2 (COX-2) induced catalysis, may play a critical role in the carcinogenesis of esophageal squamous cell carcinoma (ESCC). We investigated the efficacy of using serum PGE-2 concentration as a biomarker for this cancer type.

Material and methods

Prostaglandin-2 levels were analyzed in the serum of 65 ESCC patients and in 47 healthy individuals. The concentrations of cyclooxygenase-2 (COX-2) were measured in tumor tissues and normal tissues obtained from 31 surgically treated ESCC patients.

Results

Serum PGE-2 concentration was significantly higher in ESCC patients than in control patients (p = 0.004), especially in the early stages (I + II) of cancer (p < 0.0001). We observed significant inverse relationships between serum PGE-2 levels and: tumor stage, primary tumor progression, lymph and distant metastasis. The COX-2 concentration was significantly elevated in tumors as compared to normal tissues (p = 0.008). A significant correlation between serum PGE-2 and tumor COX-2 was observed (rho = 0.46, p = 0.009). However, ROC analysis showed that serum PGE-2 may be a weak prognostic factor for ESCC.

Conclusions

Our results suggest that an elevated concentration of serum PGE-2 in the early stages of cancer may possibly be associated with tumor initiation and cancer development in ESCC. The exact role of these findings in early detection of this highly lethal cancer requires further research.  相似文献   
47.
Dunn  EK; Macchia  RJ; Solomon  NA 《Radiology》1981,139(1):175-180
The testicular scintigraphic findings of nine patients with surgically and pathologically proved torsion of the testis of over 24 hours duration are reviewed. In the delayed blood-pool images each showed the classical avascular twisted testicle with a variable peripheral rim of hyperemia. In the dynamic blood-flow phase, eight revealed a perceptible increase of vascular perfusion in the scrotal region on the affected side, in addition to the testicular radionuclide angiogram peculiarities previously described for missed testicular torsion. This pattern of perfusion was seen only in torsion of over one day duration. A low salvage probability is expected in these cases.  相似文献   
48.
Results of thyroid biopsy determine whether thyroid nodule resection is appropriate and the extent of thyroid surgery. At our institution we use 20/22-gauge core biopsy (CBx) in conjunction with fine-needle aspiration (FNA) to decrease the number of passes and improve adequacy. Occasionally, both ultrasound (US)-guided FNA and CBx yield unsatisfactory specimens. To justify clinical recommendations for these unsatisfactory thyroid biopsies, we compare rates of malignancy at surgical resection for unsatisfactory biopsy results against definitive biopsy results. We retrospectively reviewed a database of 1979 patients who had a total of 2677 FNA and 663 CBx performed by experienced interventional radiologists under US guidance from 2003 to 2006 at a tertiary-care academic center. In 451 patients who had surgery following biopsy, Fisher’s exact test was used to compare surgical malignancy rates between unsatisfactory and malignant biopsy cohorts as well as between unsatisfactory and benign biopsy cohorts. We defined statistical significance at P = 0.05. We reported an overall unsatisfactory thyroid biopsy rate of 3.7% (100/2677). A statistically significant higher rate of surgically proven malignancies was found in malignant biopsy patients compared to unsatisfactory biopsy patients (P = 0.0001). The incidence of surgically proven malignancy in unsatisfactory biopsy patients was not significantly different from that in benign biopsy patients (P = 0.8625). In conclusion, an extremely low incidence of malignancy was associated with both benign and unsatisfactory thyroid biopsy results. The difference in incidence between these two groups was not statistically significant. Therefore, patients with unsatisfactory biopsy specimens can be reassured and counseled accordingly.  相似文献   
49.
Infectious complications after yttrium-90 (y-90) radioembolization of hepatic tumors are rare. Most reports describe hepatic abscesses as complications of other locoregional therapies, such as transcatheter arterial embolization or chemoembolization. These usually occur in patients with a history of biliary intervention and present several weeks after treatment. We report a case of hepatic abscess formed immediately after y-90 radioembolization of a hepatic metastasis in a patient who had no history of previous biliary instrumentation.  相似文献   
50.
Globally, preterm birth affects more than one in every 10 live births. Although the short-term cardiopulmonary complications of prematurity are well known, long-term health effects are only now becoming apparent. Indeed, preterm birth has been associated with elevated cardiovascular morbidity and mortality in adulthood. Experimental animal models and observational human studies point toward changes in heart morphology and function from birth to adulthood in people born preterm that may contribute to known long-term risks. Moreover, recent data support the notion of a heterogeneous cardiac phenotype of prematurity, which is likely driven by various maternal, early, and late life factors. This review aims to describe the early fetal-to-neonatal transition in preterm birth, the different structural and functional changes of the preterm human heart across developmental stages, as well as potential factors contributing to the cardiac phenotype of prematurity.  相似文献   
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