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991.
This study presents a new protocol for arthroscopic approach based on the treatment of 36 patients with extension block of the knee as a result of intra-articular reconstruction of the anterior cruciate ligament (ACL) using the patellar tendon. Arthroscopy not only allowed the identification of the active mechanical extension block of the knee, but also the passive mechanical block that can occur with a functional or loose ligament. This protocol can be useful in the treatment of postoperative extension block of the knee as a complication of ACL reconstruction.  相似文献   
992.
Precocious puberty and amenorrhea have been associated with hydrocephalus, but the pathogenesis has not been determined. Approximately 22 cases of amenorrhea, and a few cases of precocious puberty, have been reported in hydrocephalic patients. Shunt treatment leads to initiation and maintenance of normal reproductive cycles in most cases. An underlying mechanism responsible for reproductive dysfunction may involve the role of gonadotrophin releasing hormone (GnRH). The exact pathway by which hydrocephalus disrupts the hypothalamic GnRH system is unknown. However, compressive forces, ischemia, and impairment of neurotransmitter feedback loops are likely candidates.  相似文献   
993.
Caffeine modulates P50 auditory sensory gating in healthy subjects.   总被引:1,自引:0,他引:1  
The P50 suppression paradigm is an index of sensory gating assumed to reflect an inhibitory process. Adenosine is a neuromodulator with mostly inhibitory activity that is released by physiological stimuli and can be blocked by non-selective adenosine receptor antagonists such as theophylline and caffeine. A previous study showed that a single dose of theophylline decreased P50 suppression in healthy volunteers. Here we investigated the effect of caffeine (0, 100, 200 and 400 mg p.o.) on P50 sensory gating in 24 healthy volunteers (15 habitual caffeine high-users and 9 low-users). The 200 and 400 mg doses reduced P50 gating, whereas 100 mg produced a non-significant effect. The effect of caffeine was independent of gender and habitual caffeine intake. High caffeine users also showed baseline differences, with lower S(2) amplitudes compared to low-users. These results reinforce the participation of adenosine in the modulation of P50 sensory gating and suggest that caffeine ingestion should be controlled for in the P50 sensory gating paradigm.  相似文献   
994.

Background  

Organophosphorus (OPs) pesticides are the most commonly used pesticides in Peruvian agriculture. The population at risk for OPs exposure includes formulators, applicators and farmers. Majes Valley is the most important agricultural center of the Southern region of Peru. The present study was aimed to determine the knowledge about using OPs, safety practice and urinary dialkylphosphate metabolites on OP applicators in the Majes Valley, Peru.  相似文献   
995.
BACKGROUND: To evaluate the association of the PRISM III (pediatric risk of mortality) score with the infant outcome in the pediatric intensive care unit (PICU), and to determine if this score could be simplified. METHODS: A prospective cohort study was carried out with 170 infants who were consecutively admitted to the PICU. The PRISM III score with 17 physiologic variables was performed during the first 8 h of admission to the unit. Statistical analysis was done with logistic regression, odds ratios (OR) with 95% confidence intervals (95% CI), and receiver operating curve. The Alfa value was set at 0.05. RESULTS: There were 42 deaths (24.7%). The two main causes of death were septic shock (28.6%) and head trauma (16.7%). The PRISM III score had a sensitivity of 0.71, and a specificity of 0.64 as a mortality predictor. Out of the 17 physiologic variables only four of them were significant: abnormal pupillary reflexes OR 9.9 (95% CI, 3.5-28.4), acidosis OR 3.1 (95% CI, 2.0-4.9), blood urea nitrogen concentration OR 1.03 (95% CI, 1.01-1.04), and white blood cell count OR 1.02 (95% CI, 1.01-1.03). The whole logistic regression model had a coefficient of determination R(2) = 0.219, P < 0.001. CONCLUSIONS: In this setting, the PRISM III score had good sensitivity and specificity to predict mortality. This score could be simplified using only the four variables that were significant in this study. This modified PRISM III score could reduce the cost of patient care especially in developing countries PICU.  相似文献   
996.
PURPOSE: Genetic alterations were previously identified in normal epithelia adjacent to invasive cancers. The aim of this study was to determine DNA methylation in histologically normal tissues from multiple geographic zones adjacent to primary breast tumors. EXPERIMENTAL DESIGN: First, methylation status of a 4-kb region of RASSF1A promoter was interrogated using oligonucleotide-based microarray in 144 samples (primary tumors, 47; adjacent normals, 69; reduction mammoplasty tissues, 28). Second, allelic imbalance (AI)/loss of heterozygosity (LOH) surrounding RASSF1A promoter were analyzed in 30 samples (tumors, 8; adjacent normals, 22). Third, global methylation screening of 49 samples (tumors, 12; adjacent normals, 25; reduction mammoplasty, 12) was done by differential methylation hybridization. Real-time quantitative methylation-specific PCR was used to validate the microarray findings. RESULTS: DNA methylation in the core RASSF1A promoter was low in reduction mammoplasty tissues (P=0.0001) when compared with primary tumors. The adjacent normals had an intermediate level of methylation. The regions surrounding the core were highly methylated in all sample types. Microsatellite markers showed AI/LOH in tumors and some of the adjacent normals. Concurrent AI/LOH and DNA methylation in RASSF1A promoter occurred in two of six tumors. Global methylation screening uncovered genes more methylated in adjacent normals than in reduction mammoplasty tissues. The methylation status of four genes was confirmed by quantitative methylation-specific PCR. CONCLUSIONS: Our findings suggest a field of methylation changes extending as far as 4 cm from primary tumors. These frequent alterations may explain why normal tissues are at risk for local recurrence and are useful in disease prognostication.  相似文献   
997.
Background The cause of cancer in the gastric stump is multifactorial, and Helicobacter pylori is one of these factors. Its eradication has been recommended; however, there are few studies about of H. pylori eradication in gastrectomized patients. Methods Twenty gastrectomized patients with gastric adenocarcinoma and Roux-en-Y reconstruction (study group) infected by H. pylori were compared with nongastrectomized patients (control group) also infected by H. pylori. The presence of H. pylori was determined by the ultra-quick urease test and from a histological sample obtained by endoscopy. Both groups received the same triple therapy regimen. Results The rate of eradication of H. pylori in the study group was 90% and in the control group, it was 85%. Sex, age, and postoperative time did not influence the rate of eradication. Conclusion There were no differences in the efficacy of H. pylori eradication between the two groups; therefore, the triple therapy regimen is effective for the eradication of H. pylori in gastrectomized patients with a Roux-en-Y reconstruction.  相似文献   
998.
BACKGROUND: Oral contraceptive (OC) use is associated with a reduced risk of ovarian cancer. An OC component, progestin, induces apoptosis in the primate ovarian epithelium. One regulator of apoptosis is transforming growth factor-beta (TGF-beta). We determined the effect of progestin on TGF-beta expression in the primate ovarian epithelium and examined the relationship between TGF-beta expression and apoptosis. METHODS: Female cynomolgus macaques were randomly assigned to receive a diet for 35 months containing no hormones (n = 20); the OC Triphasil (n = 17); or each of its constituents, ethinyl estradiol (estrogen, n = 20) or levonorgestrel (progestin, n = 18 ), alone. Ovarian sections were immunostained with monoclonal antibodies against TGF-beta1 or TGF-beta2 plus TGF-beta3 (TGF-beta2/3) isoforms. The expression of TGF-beta isoforms in four ovarian compartments (epithelium, oocytes, granulosa cells, and hilar vascular endothelium) was compared among treatment groups. The association between TGF-beta expression and apoptosis, as determined by morphology and histochemistry, was examined in ovarian epithelium. All statistical tests were two-sided. RESULTS: Compared with ovaries from the control and estrogen-only-treated monkeys, the ovaries of progestin-treated monkeys showed 1) a marked decrease in the expression of TGF-beta1 and a concomitant increase in the expression of the TGF-beta2/3 isoforms in the ovarian epithelium (P<.001), 2) an increase in the expression of TGF-beta2/3 in the hilar vascular endothelium (P<.001), and 3) a marked decrease in TGF-beta2/3 expression in granulosa cells (P<.001). The apoptotic index of the ovarian epithelium was highly associated with the change in expression from TGF-beta1 (P<.001) to TGF-beta2/3 (P相似文献   
999.
PURPOSE: Generation of a reactive stroma environment occurs in many human cancers and is likely to promote tumorigenesis. However, reactive stroma in human prostate cancer has not been defined. We examined stromal cell phenotype and expression of extracellular matrix components in an effort to define the reactive stroma environment and to determine its ontogeny during prostate cancer progression. EXPERIMENTAL DESIGN: Normal prostate, prostatic intraepithelial neoplasia (PIN), and prostate cancer were examined by immunohistochemistry. Tissue samples included radical prostatectomy specimens, frozen biopsy specimens, and a prostate cancer tissue microarray. A human prostate stromal cell line was used to determine whether transforming growth factor beta1 (TGF-beta1) regulates reactive stroma. RESULTS: Compared with normal prostate tissue, reactive stroma in Gleason 3 prostate cancer showed increased vimentin staining and decreased calponin staining (P < 0.001). Double-label immunohistochemistry revealed that reactive stromal cells were vimentin and smooth muscle alpha-actin positive, indicating the myofibroblast phenotype. In addition, reactive stroma cells exhibited elevated collagen I synthesis and expression of tenascin and fibroblast activation protein. Increased vimentin expression and collagen I synthesis were first observed in activated periacinar fibroblasts adjacent to PIN. Similar to previous observations in prostate cancer, TGF-beta1-staining intensity was elevated in PIN. In vitro, TGF-beta1 stimulated human prostatic fibroblasts to switch to the myofibroblast phenotype and to express tenascin. CONCLUSIONS: The stromal microenvironment in human prostate cancer is altered compared with normal stroma and exhibits features of a wound repair stroma. Reactive stroma is composed of myofibroblasts and fibroblasts stimulated to express extracellular matrix components. Reactive stroma appears to be initiated during PIN and evolve with cancer progression to effectively displace the normal fibromuscular stroma. These studies and others suggest that TGF-beta1 is a candidate regulator of reactive stroma during prostate cancer progression.  相似文献   
1000.
This study compared Spanish speaking monolingual patients at a Hispanic Clinic, with Hispanics and non-Hispanics at a conventional mental health center. A questionnaire in English and Spanish surveyed sociodemographic characteristics and subjectively reported health needs. The monolingual Hispanic Clinic patients perceived a significantly greater need for help with health and benefits, and better access to physical health care providers. Hispanics seen at the Hispanic Clinic report more difficulties managing medications than the other groups suggesting that this problem is not adequately addressed by receiving services in a culturally sensitive clinic, possibly due to the persistent effect of language barriers and low level of education. Additional interventions may be needed to address this problem.  相似文献   
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