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991.
We examined the synaptic targets of large non-gamma-aminobutyric acid (GABA)-ergic profiles that contain round vesicles and dark mitochondria (RLD profiles) in the perigeniculate nucleus (PGN) and the dorsal lateral geniculate nucleus (dLGN). RLD profiles can provisionally be identified as the collaterals of thalamocortical axons, because their ultrastrucure is distinct from all other previously described dLGN inputs. We also found that RLD profiles are larger than cholinergic terminals and contain the type 2 vesicular glutamate transporter. RLD profiles are distributed throughout the PGN and are concentrated within the interlaminar zones (IZs) of the dLGN, regions distinguished by dense binding of Wisteria floribunda agglutinin (WFA). To determine the synaptic targets of thalamocortical axon collaterals, we examined RLD profiles in the PGN and dLGN in tissue stained for GABA. For the PGN, we found that all RLD profiles make synaptic contacts with GABAergic PGN somata, dendrites, and spines. In the dLGN, RLD profiles primarily synapse with GABAergic dendrites that contain vesicles (F2 profiles) and non-GABAergic dendrites in glomerular arrangements that include triads. Occasional synapses on GABAergic somata and proximal dendrites were also observed in the dLGN. These results suggest that correlated dLGN activity may be enhanced via direct synaptic contacts between thalamocortical cells, whereas noncorrelated activity (such as that occurring during binocular rivalry) could be suppressed via thalamocortical collateral input to PGN cells and dLGN interneurons.  相似文献   
992.

Aim

The aim of this study was to determine outcomes, including weight gain, morbidity, and mortality, of children with severe congenital heart disease who underwent fundoplication (FP) for gastroesophageal reflux disease.

Methods

An institutional review board-approved retrospective review was conducted on all children with congenital heart disease who underwent FP from 1999 to 2005. Preoperative age, weight, cardiac procedures, postoperative weight, and mortality were extracted from medical records. The Wilcoxon signed rank, Wilcoxon rank sum, and log-rank tests were used; P value less than .05 was significant. All procedures were performed with dedicated cardiac anesthesia personnel with recovery in a cardiac intensive care unit.

Results

Of 112 subjects identified, 37 (33%) had single ventricle (SV) physiology. The most frequent cardiac procedures performed were Norwood (33), pulmonary artery band (11), and systemic pulmonary artery shunt (11). A total of 104 laparoscopic FPs (with 2 conversions to open) and 8 open FPs were performed. The median preoperative age was 3 months, and weight percentile was 1.5%. From baseline, postoperative median weight percentiles increased to 4% at 3 months (P < .001) and to 20% at 5 years postoperatively (P = .004). Single ventricle physiology had no significant effect on outcomes. Postoperative mortality (≤30 days) was 4.5% (5/112); 5-year survival was 74% (83/112). Five-year survival of SV subjects (59%) was significantly lower (P = .03) than that of the other subjects (81%). No significant difference in survival was seen between SV subjects with FP and all SV patients seen at our center during the study period. Only one death was directly related to antireflux surgery (SV subject). There were 8 patients who had recurrent gastroesophageal reflux disease: 4 were treated with reoperation, and 4 were treated medically.

Conclusion

Weight gain in this high-risk population can be expected after antireflux surgery. Mortality is high because of intrinsic disease, especially in the SV population. Fundoplications performed with the assistance of dedicated pediatric cardiac anesthesia personnel followed by recovery in a cardiac intensive care unit is possible with acceptable postoperative morbidity and mortality.  相似文献   
993.
994.
995.
Improving state pain policies: recent progress and continuing opportunities   总被引:1,自引:0,他引:1  
The National Institutes of Health reports that 100 million Americans suffer from chronic pain, including pain associated with the disease of cancer. Painful conditions can strike anyone, including cancer patients and cancer survivors. Unrelieved severe pain can limit a person's functioning and sometimes even destroy the will to live. When the quality of pain relief provided is inadequate, it is usually the result of failures to apply existing knowledge about pain and its treatment, including the appropriate use of opioids. But pain relief also can be affected by the regulatory environment and fear of being investigated for excessive prescribing. The importance of evaluating and improving policies governing pain management has been recognized by national and international authorities, including the Institute of Medicine and the World Health Organization. A pilot examination of state laws and regulatory policies demonstrated that they contained a number of outdated medical concepts and prescribing restrictions and did not contain key elements of law that can make pain management a priority for licensed medical practitioners. The Pain & Policy Studies Group developed a research program to evaluate US federal and state policy governing the medical use of pain medication. This article describes 3 national policy evaluations and how the results are being used to document improvements in state pain policies. An emerging role for clinicians and their professional organizations to improve their state's pain policies is discussed.  相似文献   
996.
997.
Associations between oral contraceptive (OC) use and breast cancer have been reported, but few studies have considered associations in racial and ethnic minorities. Data regarding injected or implanted hormonal contraceptives are limited. In a case-control study of Hispanic (796 cases, 919 controls) and non-Hispanic white (1,522 cases, 1,596 controls) women in the U.S. southwest interviewed in 2000-2005, 49% of Hispanic controls and 66% of non-Hispanic white controls reported having used OC. Breast cancer odds ratios (OR) associated with OC use within the past 5 years were 1.22 (95% confidence interval (CI) 0.80, 1.84) among Hispanics, 1.28 (95% CI 0.93, 1.76) among non-Hispanic whites, 1.27 (95% CI 0.99, 1.63) for both ethnic groups combined and 1.53 (95% CI 0.98, 2.40) for estrogen receptor (ER) negative tumors. OC use for 20 years or longer was associated with ORs of 1.50 (95% CI 1.04, 2.17) for both ethnic groups combined, and 2.23 (95% CI 1.17, 4.25) for ER negative tumors. Hormonal contraceptive injections were used by 3.3% of Hispanic controls and 2.8% of non-Hispanic white controls, OR 1.23 (95% CI 0.88, 1.73). Fifteen cases and 2 controls reported use of a subdermal contraceptive implant, OR 8.59 (95% CI 1.92, 38.39). Associations between OC use and breast cancer in Hispanics are consistent with modestly increased risk among recent users and for ER negative tumors, as observed in other populations. Based on a small number of users of contraceptive implants, a significantly increased breast cancer risk was observed; continued surveillance of implant users may be warranted.  相似文献   
998.
This study investigated associations between CpG island methylator phenotype (CIMP) colon cancer and genetic polymorphisms relevant to one-carbon metabolism and thus, potentially the provision of methyl groups and risk of colon cancer. Data from a large, population-based case-control study (916 incident colon cancer cases and 1,972 matched controls) were used. Candidate polymorphisms in methylenetetrahydrofolate reductase (MTHFR), thymidylate synthase (TS), transcobalamin II (TCNII), methionine synthase (MTR), reduced folate carrier (RFC), methylenetetrahydrofolate dehydrogenase 1 (MTHFD1), dihydrofolate reductase (DHFR) and alcohol dehydrogenase 3 (ADH3) were evaluated. CIMP- or CIMP+ phenotype was based on five CpG island markers: MINT1, MINT2, MINT31, p16 and MLH1. The influence of specific dietary factors (folate, methionine, vitamin B(12) and alcohol) on these associations was also analyzed. We hypothesized that polymorphisms involved in the provision of methyl groups would be associated with CIMP+ tumors (two or more of five markers methylated), potentially modified by diet. Few associations specific to CIMP+ tumors were observed overall, which does not support the hypothesis that the provision of methyl groups is important in defining a methylator phenotype. However, our data suggest that genetic polymorphisms in MTHFR 1,298A > C, interacting with diet, may be involved in the development of highly CpG-methylated colon cancers. AC and CC genotypes in conjunction with a high-risk dietary pattern (low folate and methionine intake and high alcohol use) were associated with CIMP+ (OR = 2.1, 95% CI = 1.3-3.4 versus AA/high risk; P-interaction = 0.03). These results provide only limited support for a role of polymorphisms in one-carbon metabolism in the etiology of CIMP colon cancer.  相似文献   
999.
The International Working Group for Myelofibrosis Research and Treatment (IWG-MRT) is comprised of hematologists, hematopathologists, and laboratory scientists and its main goal is to provide a forum for scientific exchange and collaboration. During its first general meeting in April 2006, the IWG-MRT established uniform treatment response criteria for chronic idiopathic myelofibrosis (CIMF); also known as agnogenic myeloid metaplasia (AMM), myelofibrosis with myeloid metaplasia (MMM), and many other names in the hematologic literature. This document summarizes the proceedings from the second meeting of the IWG-MRT, in November 2006, where the group discussed and agreed to standardize the nomenclature referring to CIMF: (i) the term primary myelofibrosis (PMF) was chosen over several other designations including CIMF, AMM, and MMM, (ii) myelofibrosis that develops in the setting of either polycythemia vera (PV) or essential thrombocythemia (ET) will be referred to as post-PV MF and post-ET MF, respectively, and (iii) "leukemic" transformation will be recognized as blast phase disease (PMF-BP, post-PV/ET MF in blast phase).  相似文献   
1000.
INTRODUCTION: The incidence of breast cancer varies among women living in the Southwestern part of the US. We evaluate how body size influences breast cancer risk among these women. METHODS: Cases (n = 2,325) diagnosed with breast cancer between October 1, 1999 and May 2004 residing in Arizona, Colorado, New Mexico, or Utah were matched to controls (n = 2,525). Participants were interviewed; height, weight, waist, and hip circumference were measured at the time of interview; blood was drawn. RESULTS: A large body mass index (BMI) at age 15 was inversely associated with pre-menopausal breast cancer risk in both non-Hispanic white (NHW) and Hispanic women (Odds ratio, ORs 0.68 95% CI 0.44, 1.04, and 0.65 95% CI 0.39, 1.08, respectively); BMI at age 15 also had an impact on subsequent breast cancer associated with obesity after menopause. Among post-menopausal women, recent exposure to hormones was an important modifier of risk associated with body size. Among women not recently exposed to hormones risk associated with obesity was 1.61 (95% CI 1.05, 2.45) for NHW women; gaining > or = 25 kg between 15 and age 50 was inversely associated with breast cancer among Hispanic women (OR 0.51, 95% CI 0.23, 1.14). A large weight gain and a large waist-to-hip ratio (WHR) was associated with an increased odds of having an estrogen receptor negative tumor among NHW only (OR 1.81, 95% CI 1.07, 3.08, and 2.04 95% CI 1.20,3.50). CONCLUSIONS: These findings suggest that the metabolic consequences of obesity on breast cancer risk differ between NHW and Hispanic women living in the Southwest.  相似文献   
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