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161.
The historical concept that obesity protects against bone fractures has been questioned. Weight loss appears to reduce bone mineral density (BMD); however, the results in young adults are inconsistent, and data on the effects of weight loss on bone microstructure are limited. This study aimed to evaluate the impact of weight loss using an intragastric balloon (IGB) on bone density and microstructure. Forty obese patients with metabolic syndrome (mean age 35.1?±?7.3 yr) used an IGB continuously for 6 mo. Laboratory tests, areal BMD, and body composition measurements via dual-energy X-ray absorptiometry, and volumetric BMD and bone microstructure measurements via high-resolution peripheral quantitative computed tomography were conducted before IGB placement and after IGB removal. The mean weight loss was 11.5%. After 6 mo, there were significant increases in vitamin D and carboxyterminal telopeptide of type 1 collagen levels. After IGB use, areal BMD increased in the spine but decreased in the total femur and the 33% radius. Cortical BMD increased in the distal radius but tended to decrease in the distal tibia. The observed trabecular bone loss in the distal tibia contributed to the decline in the total volumetric BMD at this site. There was a negative correlation between the changes in leptin levels and the measures of trabecular quality in the tibia on high-resolutionperipheral quantitative computed tomography. Weight loss may negatively impact bone microstructure in young patients, especially for weight-bearing bones, in which obesity has a more prominent effect.  相似文献   
162.
Prevention and control of hospital acquired infections is a constant challenge for the nursing professionals. This study sought to grasp the social representations of hospital-acquired infections elaborated from the perceptions of nursing professionals, and to discuss how these representations influence their practices in controlling and preventing infections. This is a qualitative research, applied in a reference urgency-emergence service, which used as a data collection technique the semi-structured interview, and for content analysis the category elaboration. It was observed that the execution of the activities is closely tied to the individual subjectivities of each professional and deeply dependant on the moral, ethical, ideological and subjective values of these professionals, regarding interpretation, judging and personal decision in the application of the scientific knowledge.  相似文献   
163.

Purpose

To evaluate the immunohistochemical expression of nitric oxide synthase (NOS) types 1, 2, and 3 in intratumoral and non-neoplastic samples of renal cell carcinoma (RCC) and correlate it with the clinical and pathological features of this malignancy.

Methods

We analyzed 110 patients with RCC underwent radical nephrectomy (RN) or partial nephrectomy (PN) by streptavidin–biotin peroxidase method, tissue microarray, and digital microscopy. As endpoints, NOS expression was correlated with pathological features, overall survival (OS), and cancer-specific survival (CSS).

Results

Non-neoplastic samples had higher NOS3 and lower NOS 2 levels than RCC tissues. Greater expression of all NOS isoforms was associated with larger tumors. High NOS1 expression correlated with microscopic venous invasion (MVI) (p = 0.046) and lymph node metastases (p = 0.007). High NOS2 expression was linked to MVI, more RN performed, and male gender (p = 0.035, p = 0.003, and p =  0.027, respectively). High NOS3 expression correlated with lymph node metastases (p = 0.039), microlymphatic invasion (p = 0.029), invasion of the renal pelvis and ureter (p = 0.004), RN (p = 0.003), and shorter OS (58.1 vs. 79.4 % respectively, p = 0.033) by univariate analysis. DFS was not influenced by any NOS isoform. By multivariate analysis, the risk factors for death were TNM stages III and IV (hazard ratio [HR] = 4.5), high Fuhrman’s grade (HR = 2.9), Karnofsky performance status ≤80 (HR = 2.5), progression (HR = 5.5), and recurrence (HR = 6.3). Stage III disease was an independent risk factor for recurrence (HR = 9.5).

Conclusions

High NOS expression in RCC is associated with a poor prognosis and larger tumors. NOS3 influences OS by univariate analysis.  相似文献   
164.
It is unusual the association between hypertrophic cardiomyopathy and atrial septal defect. We present in this paper the results of the tests done to one patient with these two diseases and profit to make an update of the bibliography on this subject.  相似文献   
165.
The thermophilic eubacterium Bacillus stearothermophilus has been used as a model system to identify DDT-promoted events in biological membranes putatively related with the insecticide toxicity. Two strategies have been approached: a) bacterial growth and viability were followed and the effects of DDT (2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane) determined; b) biophysical studies with fluorescent probes were performed to elucidate the effects of DDT on the organization of the membrane lipid bilayer. The effects of DDT on growth and physical properties of the membrane were also determined in the presence of Ca2+ to further identify the interference of the insecticide at the membrane level and its putative contribution to cell toxicity. Growth inhibition by DDT is concentration-dependent, being attenuated or removed by the addition of 2.5-mM Ca2+ to bacterial cultures. Consistently, fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) and its propionic acid derivative (DPH-PA) exhibited opposite effects of Ca2+ and DDT on the physical state of bacterial polar lipid dispersions. Growth and viability of bacterial cells are affected by DDT concentrations lower than those able to induce detectable bulk fluidity alterations, indicating high sensitivity of the intact bacterial system to alterations in limited membrane domains not directly probed by fluorescent probes that only report the average behavior of membrane lipid population. Received: 10 September 1996/Accepted: 7 December 1996  相似文献   
166.
We report 7 cases of severe Peyronie's disease treated with a modified surgical technique of the one described in 1989. This second version consists of making only one I-shaped incision on the dorsal face of the penis, in order to relax and create a defect in the tunica albuginea, which is then covered with a patch of human lyophilized dura mater. The plastic and sexual results were identical to the ones described previously, but the operative time was shortened. This type of surgery is indicated to correct severe angulation and shortening of the penis in men with normal sexual lives.  相似文献   
167.
There is a growing body of evidence indicating that chronic alcohol consumption induces morphological changes in the central nervous system (CNS) similar to those observed during brain senescence, including an increased formation of lipofuscin. In addition, it was also found that alcohol withdrawal does not reverse these changes. On the contrary, most of the alterations observed during alcohol consumption worsen as happens with the increased lipofuscin formation. Thus, using our model of alcohol feeding and withdrawal, we decided to examine the effects of different drugs said to offer neuronal protection during CNS degenerative processes. The action of piracetam, a cyclic derivate of GABA and commonly used as a nootropic agent, was tested by studying the lipofuscin accumulation on the cerebellar Purkinje and hippocampal CA3 pyramidal cells in alcohol-treated and withdrawn rats. Piracetam was found to markedly decrease the formation of neuronal lipofuscin. Whatever the functional implications of this pigment, its reduction in piracetam-treated animals might be related either to a protective effect on the intraneuronal membranous system or to an antioxidant property of this molecule.  相似文献   
168.
169.
Epidural mastoid pneumatocele   总被引:1,自引:0,他引:1  
Madeira  JT; Summers  GW 《Radiology》1977,122(3):727
  相似文献   
170.
Defective yeast opsonization in sera with no demonstrable abnormality of known complement components is associated with the absence of inactivity of a co-factor which enhances the deposition of C3 fragments (C3b/C3bi) derived from both classical and alternative pathways of complement activation. The factor binds strongly to zymosan at 4 degrees C and loses its biological activity completely when heated for 30 min at 56 degrees C but not when similarly heated at 50 degrees C. Sera with defective deposition of C3 fragments may be readily corrected with small quantities of sera having normal function. Sera with the defect do not correct other similar sera.  相似文献   
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