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111.
Interstitial cystitis and chronic prostatitis/chronic pelvic pain syndrome are clinical syndromes characterized by pelvic pain with or without voiding symptoms such as urgency and frequency. There are many similarities in their epidemiology, adverse effect on quality of life, etiology/pathophysiology, natural history, and response to similar treatments. However, overlapping clinical definitions and similar entrance criteria for large-scale cohort studies make comparisons problematic. Newer efforts to classify pelvic pain syndromes should help in our recognition that interstitial cystitis and chronic prostatitis/chronic pelvic pain syndrome likely are not organ-specific syndromes but urogenital manifestations of regional or systemic abnormalities.  相似文献   
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113.
Eye contact is a powerful social stimulus for human and non-human primates. However, it is unclear whether brain mechanisms that interpret eye contact are sensitive to gender. Here we show that human brain responses to eye contact are indeed gender specific. Recording event-related potentials directly from the medial temporal lobes, we found that eye contact elicited specific responses in men only when they saw female faces. Conversely, women responded specifically to eye contact only when they saw pictures of men. Thus, the human medial temporal lobes subserve specifically the processing of eye contact with persons of the opposite gender.  相似文献   
114.
BACKGROUND: Reactive oxygen species play a major role in the development of endothelial dysfunction. It is as yet unspecified whether increased oxidative stress contributes to endothelial dysfunction of the renal vasculature in patients with type 2 diabetes. METHODS: Renal haemodynamics were studied in 20 patients with type 2 diabetes and arterial hypertension (age 62 +/- 5 years) and 20 non-diabetic hypertensive patients at baseline and following infusions of the nitric oxide synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA; 4.25 mg/kg); the substrate of nitric oxide synthase, L-arginine (100 mg/kg); and the antioxidant, vitamin C (3 g, co-infused with L-arginine 100 mg/kg). RESULTS: The response of renal plasma flow (RPF) to L-NMMA (-54 +/- 62 and -45 +/- 42 ml/min/1.73 m(2); P = NS) and L-arginine (+46 +/- 36 and +49 +/- 25 ml/min/1.73 m(2); P = NS) was not different between diabetic and non-diabetic patients. In contrast, vitamin C induced a more pronounced increase in RPF in diabetic than in non-diabetic patients when co-infused with L-arginine (+71+/-47 and +43+/-33 ml/min/1.73 m(2); P<0.05). CONCLUSIONS: The difference in the response of renal perfusion to an antioxidant suggests increased formation of reactive oxygen species and thereby reduced nitric oxide bioavailability in the renal vasculature of patients with type 2 diabetes.  相似文献   
115.
Large mandibular defects caused by trauma, infection or resection of a tumour are still a major problem for plastic and maxillofacial surgeons. The modern concept of tissue engineering combines the osteoinductive effects of osteogenic cells with a suitable scaffold structure to promote differentiation of osteoblasts and optimal matrix production. Critical size mandibular bone defects were therefore made to investigate the osteogenic potential of periosteal cells and a bioabsorbable polymer fleece (Ethisorb 510) in minipigs. Periosteal cells were isolated from four minipigs, expanded in vitro and seeded with fibrin glue into Ethisorb 510 fleeces. Tissue constructs were used to repair critical size mandibular defects and compared with two minipigs with untreated bone defects. Bone healing was evaluated after 90 and 180 days by radiographs and a histological scoring system. The radiographs showed increased radiodensity of defects filled with the cell-fibrin-fleece-constructs compared with the untreated control group after 90 and 180 days in vivo. The defects repaired by the cell-fibrin-scaffolds (180 days in vivo) obtained the highest histological mean score 2.9 (range 2-3), while defects filled by cell-fibrin-scaffolds (90 days in vivo) achieved a mean score of 2.1 (range 2-3). In contrast, the control group (n = 2) scored 1 and 2. The results show that a combination of periosteal cells and polymer fleeces may be a promising approach for clinical mandibular augmentation.  相似文献   
116.
Rn-222 is the most important source of natural radiation and is responsible for approximately half of the received dose from all sources. Most of this dose is from inhalation of the Rn-222 progeny, especially in closed atmospheres. A Lucas cell technique, using a portable device, “PRASSI” (SILENA mod. 5S), for Rn-222 measurements inside the Centre for Radiation Protection and Radioecology (ZSR), Hannover University was used. The portable radon monitor PRASSI is suitable for radon gas continuous or grab sampling measurements with the scintillation cell technique. In recognition of the wide periodic variations in concentration, measurements were made daily for extended periods. At the same time, meteorological variables, such as temperature and humidity were observed so that their influence on radon levels could be evaluated. The radon average concentration during the year was about 55.9 Bq/m3 which gives rise to an annual effective dose 2.2 mSv y−1. The radon concentration is within the limits prescribed by the International Commission for Radiation Protection. A detailed analysis of radon distribution with seasonal variation is presented.  相似文献   
117.
Transplant atherosclerotic coronary disease remains the leading cause of death in heart transplant recipients. We report the first case of coronary stent implantation in a heart graft for epicardial focal stenosis. Due to the lower rate of restenosis after stenting in the native coronary artery, we suggest that coronary stenting be considered an acceptable, first intention therapeutic option instead of angioplasty alone whenever possible.  相似文献   
118.
Complications following free tissue transfer have been well established in the literature. Common and rare causes of free flap failure must be addressed by the treating surgeon when microvascular patency is threatened. With the evolution and prevalence of microsurgery, ‘rare’ causes of free flap failure will become increasingly frequent. A high index of suspicion must be established in patients with multiple failed operative interventions. A case of recurrent free flap failure secondary to heparin-induced thrombocytopenia is presented in a patient with a history of squamous cell carcinoma of the floor of the mouth, and a long-standing history of alcohol and tobacco consumption.  相似文献   
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120.
Neutral endopeptidase 24.11 (EC 3.4.24.11) inactivates atrial natriuretic peptide by cleaving the hormone between Cys7 and Phe8, and inhibitors of the enzyme have consequent natriuretic and diuretic properties. The in vivo sites of degradation of this peptide by the zinc-metallopeptidase, however, remain to be established. Because an endopeptidase-24.11-like activity has recently been reported in the rat mesenteric artery, we have further investigated the degradation of atrial natriuretic peptide in vascular tissue. Endopeptidase-24.11 activity was detected in solubilized membrane preparations from rat and rabbit vascular tissue, using [3H]D-Ala2-leucine enkephalin as substrate, and both rabbit and rat aorta preparations were also found to cleave atrial natriuretic peptide between Cys7 and Phe8. In both cases, hydrolysis was inhibited by neutral endopeptidase inhibitors, with Ki values close to their Ki values for the pure enzyme. In preparations of rabbit aorta denuded of endothelium by saponin treatment, the hydrolysis of the Gly3-Phe4 bond of [3H]D-Ala2-leucine enkephalin and the Cys7-Phe8 bond of atrial natriuretic peptide was reduced by greater than 90%. The high performance liquid chromatography method used to follow the degradation of atrial natriuretic peptide differed from previously published procedures, in that samples to be injected were first treated with excess dithiothreitol to reduce the Cys7-Cys23 disulfide bridge. This facilitated the separation of the intact peptide and its metabolites. The presence of the 94-kDa neutral endopeptidase in rabbit aortic tissue was definitively established using a new potent 125I-labeled inhibitor, [125I]RB104 [2-[(3-[125I]iodo-4-hydroxy)phenylmethyl]-4-N-[3- hydroxyamino-3-oxo-1-phenylmethyl propyl]amino-4-oxobutanoic acid] (Ki, 30 pM), which selectively labeled the enzyme after sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the membrane preparations. Therefore, despite its low concentrations in the vasculature, the presence of endopeptidase-24.11 almost exclusively in endothelial tissue suggests that the enzyme is ideally localized to inactivate circulating atrial natriuretic peptide.  相似文献   
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