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1.
Abdominal Radiology - Metastatic involvement of the ovaries is not rare. The most common tumor types metastasizing to the ovaries, from non-gynecological organs, are breast, colorectal, gastric,...  相似文献   
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Insulin deficiency is known to be associated with a state of increased muscle protein breakdown; this process is mediated by the ubiquitin-proteasome pathway. Convincing in vitro data are further supported by extensive studies in humans with insulin deprivation and are further substantiated by reversal of muscle protein breakdown with insulin treatment. In patients with end-stage renal disease (ESRD) and diabetes mellitus (DM), muscle protein breakdown is enhanced in both acute and chronic conditions. Recent data also point to the potential protein catabolic effects of insulin resistance combined with insulin deficiency. Because ESRD is associated with a state of insulin resistance, uremic muscle wasting may also be mediated by this pathway.  相似文献   
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OBJECTIVE: Radial arteries are increasingly used as conduits for coronary artery bypass grafts, but perioperative graft vasospasm remains a concern. In vitro testing has demonstrated the efficacy of phenoxybenzamine and verapamil/nitroglycerin as topical antispasmodic agents, but their duration of action in vivo is unknown. Using an in vivo mouse model, we measured their duration of action in functioning vascular grafts, and compared this to their in vitro duration of action in ungrafted vascular segments. METHODS: Two millimetre mouse aortic segments (C57/BL6) were incubated with phenoxybenzamine, verapamil/nitroglycerin, or buffer (controls) for 15 min in organ chambers. Isometric tension responses to phenylephrine and prostaglandin F2alpha were measured at 0, 2, 6 and 12 h post-incubation. In parallel, 36 murine infrarenal aortic interposition grafts (2 mm) were performed. Twelve grafts were pre-treated (15 min) with phenoxybenzamine, 12 with verapamil/nitroglycerin and 12 remained untreated (controls). Isometric tension responses to the same agonists were measured in grafts harvested 2, 6, 13 and 23 h after surgery. RESULTS: Phenoxybenzamine prevented alpha-adrenergic vasoconstriction for up to 16 h in vivo (grafts), and 12h in vitro (ungrafted segments). Verapamil/nitroglycerin was effective for at least 2 h in vitro, but did not prevent vasoconstriction after 2 h in vivo. CONCLUSIONS: The mouse model appears to be a useful technique for assessing the pharmacological properties of antispasmodic agents in vivo. Phenoxybenzamine has an extended action in arterial grafts in vivo. Verapamil/nitroglycerin is short-lived in vivo but lasts longer in vitro. Measurements of antispasmodic duration of action in vitro should be interpreted with caution.  相似文献   
5.
OBJECTIVE: To determine physical activity patterns in chronic hemodialysis patients with a specific emphasis on the difference between dialysis and nondialysis days. Design A cross-sectional single-center study. SETTING: Vanderbilt University Outpatient Dialysis Unit. PATIENTS: Twenty current chronic hemodialysis patients: 10 male, 10 female; 15 black, 5 white; mean age, 50.1 +/- 9.9 years; height, 164.5 +/- 10.9 cm; weight, 82.5 +/- 15.4 kg; length on dialysis, 57.3 +/- 45.3 months. METHODS: Minute-by-minute physical activity was assessed over a 7-day period using a triaxial accelerometer, which consists of raw numbers or counts calculated by the 3 axes of the accelerometer (PA counts). PA counts were extrapolated on a daily and hourly basis. Physical functioning tests included: sit-to-stand, 6-minute walk, and 1-repetition maximal leg press exercise. Laboratory values for serum concentrations of albumin, prealbumin, C-reactive protein, and cholesterol were also collected. MAIN OUTCOME MEASURE: PA counts. RESULTS: Total PA counts were significantly lower on dialysis days when compared with nondialysis days (128,279 +/- 74,009 versus 168,744 +/- 95,168, respectively, P = .025). The average PA counts during the 4-hour dialysis time period were significantly lower on dialysis days when compared with nondialysis days (3,086 +/- 3,749 versus 11,070 +/- 7,695, respectively, P = .001). At postdialysis hours 1 and 2, PA counts on dialysis days were significantly higher than on nondialysis days (11,410 +/- 5,340 versus 9,082 +/- 6,646, P = .008, and 14,048 +/- 9,728 versus 8,662 +/- 6,433, P = .016, respectively). By postdialysis hour 4, PA counts on dialysis days had significantly decreased when compared with nondialysis days (6,068 +/- 6,268 versus 10,512 +/- 7,420 PA counts, P = .01, respectively). From postdialysis hours 5 to 20, there was no significant difference in PA counts between dialysis and nondialysis days. CONCLUSION: This study shows that physical activity is lower on dialysis days when compared with nondialysis days, and this decrease is caused by the lack of activity during the 4-hour hemodialysis procedure. New behavior modification strategies involving physical activity, both during hemodialysis and on nondialysis days, must be examined in this patient population.  相似文献   
6.
The results of percutaneous radiofrequency rhizotomy of lumbar spinal facets in 46 patients followed at least three months (mean 15 months) are reported and compared with those reported previously. Satisfactory pain relief three months after the procedure was achieved in 36.4 percent of patients without operations and in 41.7 percent of patients with operations other than fusion.No patient had previously undergone fusion.Treatment of low-back pain by using radio-frequency thermocoagulation of spinal facets is a simple, safe, and well-tolerated procedure. It can be used to relief of pain in spite of decreasing rates of success within the follow-up period.  相似文献   
7.
Sympathetic skin responses from postauricular region in Meniere's disease.   总被引:10,自引:0,他引:10  
OBJECTIVE: To investigate the sympathetic nervous system activity in Meniere's disease (MD) by recording sympathetic skin responses (SSRs) from the postauricular region (PA). METHODS: Twenty-one patients with definite unilateral MD diagnosis and 12 healthy volunteers were studied by evoking right and left PA-SSRs with electrical stimulation of the left median nerve at the wrist in attack and interval periods of MD. Mean latencies and maximum amplitudes were used in statistical analyses. RESULTS: In unilateral definite MD patients, the mean latencies were longer and the maximum amplitudes were smaller on the involved ear side than those on the normal ear side (p<0.01 for both amplitude and latency) and than those from the controls (p<0.01 and p<0.05). In three patients, there was no detectable PA-SSR on the involved ear side while there were SSRs on the healthy side. In four patients, the responses were absent bilaterally during the attack period. CONCLUSIONS: There is a marked asymmetric sympathetic hypofunction in the area of the PA region of the involved ear in MD patients. SIGNIFICANCE: The PA region is a new site for recording sympathetic skin responses. PA-SSR is a useful tool to investigate sympathetic nervous system function in MD patients.  相似文献   
8.
Leukocyte arylsulphatase A (AS-A) was shown to be significantly high in newly-diagnosed breast cancer patients. Previous reports imply a connection between serum interleukin-6 (IL-6) and breast cancer, possibly through a modulation of enzymes involved in estrogen synthesis. Abnormal distribution of heparan sulphate proteoglycans (HSPGs) in malignant breast epithelial cells suggests that they play a key role in the regulation of cell growth. Estradiol is believed to be effective in modulating glycosaminoglycans (GAGs) and their depolymerizing enzymes. Therefore, in this study, attempts were made to evaluate the activity of leukocyte arylsulphatase A, serum interleukin-6, urinary GAGs and heparan sulphate (HS) in response to tamoxifen (TAM) therapy in mastectomised breast cancer patients. Thirty-four patients (aged 30-82 years) were administered TAM (20 mg twice daily). Blood and urine samples of each patient were collected three times (at the beginning, and in third and sixth month of TAM therapy), and biochemical parameters were measured. There was no difference between baseline leukocyte AS-A activity and that measured after three months. At the end of six months, enzyme activity was significantly higher than the former values (p=0.022), but within the reference intervals reported in the literature. Although this increase might imply a normalization, the duration of TAM therapy is not long enough to make a decision about either regression or aggravation of the disease. TAM did not have any effect on serum IL-6, urinary HS and GAG levels which may be due to insensitivity of these variables to TAM during the short period of therapy. Both urinary GAG and HS levels measured at sixth month exhibited a positive correlation with the baseline level of leukocyte AS-A (p=0.005 and 0.009, respectively), suggesting that positive responses to the drug might be seen in patients with low AS-A activity.  相似文献   
9.
OBJECTIVE: The objective of this study was to determine the prevalence of sexual dysfunction in patients with schizophrenia under antipsychotic therapy and to investigate the effect of various parameters on sexual dysfunction. METHOD: A total of 827 stabilized outpatients who met DSM-IV criteria for schizophrenia, were recruited in the study. Arizona Sexual Experience Scale (ASEX) and the subscale on sexual function of the UKU Side Effects Rating Scale were applied at a single interview. RESULTS: In total, 52.6% of the patients had sexual dysfunction, 54.2% reported a low sexual desire and 41.7% reported problems in having an orgasm. Erectile dysfunction and ejaculation problems were seen in 48.1% and 64.2% of the men, respectively; amenorrhea was seen in 24.9% of the women. ASEX score and severity of disease were found to be correlated (p=0.02). Higher ASEX scores were observed in patients who smoked (p=0.01). Men receiving atypical monotherapy had lower ASEX scores than those receiving a combination of atypical and conventional antipsychotics (p=0.017). Patients on combination therapy had more ejaculation problems than the atypical group (p=0.001). Low sexual desire was more prevalent among women using conventional drugs than those on atypical drugs (p=0.004). In linear regression analyses, ASEX was affected significantly and independently by the severity of the disease only in men (p=0.005). CONCLUSION: Our results show that sexual dysfunction is widespread among patients with schizophrenia on antipsychotic medications.  相似文献   
10.
OBJECTIVE: The study objective was to examine the relationship between visceral and somatic protein stores and physical activity in individuals with end-stage renal disease. DESIGN: This was a prospective single-center study. SETTING: The study took place at the Vanderbilt University Outpatient Dialysis Unit and General Clinical Research Center. PATIENTS: Fifty-five patients with prevalent chronic hemodialysis (CHD) were included: 33 males, 22 females, 45 African Americans, 9 Caucasians, and 1 Asian. The mean age was 47.0 +/- 1.6 years, height was 166.4 +/- 13.9 cm, and weight was 83.1 +/- 2.6 kg. METHODS: Body composition was measured by dual-energy x-ray absorptiometry. Minute-by-minute physical activity was assessed over a 7-day period with a triaxial accelerometer. Participants were interviewed by a trained registered dietitian for two 24-hour diet recalls (one from a hemodialysis day; one from a nonhemodialysis day). Laboratory values for serum concentrations of albumin, prealbumin, C-reactive protein, and creatinine were also collected. MAIN OUTCOME MEASURE: Predictors of somatic protein stores were the main outcome measure. RESULTS: Serum albumin was negatively and significantly correlated with the percentage of fat mass (P = .016) and kg of fat mass (P = .044). C-reactive protein was positively and significantly correlated with body weight (P = .006), percentage of fat mass (P = .017), kg of fat mass (P = .006), and body mass index (P = .004). Physical activity and total daily protein intake were the strongest predictors of the amount of lean body mass (P = .01 and .003, respectively). CONCLUSION: The association between somatic protein and visceral protein stores is weak in patients with CHD. Whereas increased levels of physical activity and total daily protein intake are associated with higher lean body mass in patients with CHD, higher adiposity is associated with higher C-reactive protein and lower albumin values.  相似文献   
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