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81.
Why we should regionalize perinatal care   总被引:2,自引:0,他引:2  
J F Lucey 《Pediatrics》1973,52(4):488-491
  相似文献   
82.
This study aims to determine the in vitro susceptibility of Helicobacter pylori to clarithromycin, metronidazole, amoxycillin and tetracycline, the four antibiotics commonly used in eradication therapies. These data are used to evaluate the efficacy of current empiric treatment of H. pylori infection in the Southern Region of Ireland. Culture is performed on gastric biopsy samples obtained from 147 consecutive patients undergoing gastroscopy for investigation of dyspepsia. Susceptibility testing to metronidazole, clarithromycin, amoxycillin and tetracycline is performed on the isolates by Etest. Isolates demonstrating clarithromycin resistance are subjected to polymerase chain reaction (PCR) amplification and nucleotide sequence analysis to identify the presence of point mutations in the peptidyltransferase region of the 23S rRNA gene previously associated with resistance to clarithromycin. Prevalence of H. pylori in the population studied was 31% (45 isolates). Antimicrobial resistance to metronidazole and clarithromycin was detected in nine (20%) and four (8.9%) of the isolates, respectively. A single isolate demonstrated co-resistance to metronidazole and clarithromycin (2.2%). No resistance was detected to either amoxycillin or tetracycline. The low level of resistance demonstrated among this group of isolates indicates that the empiric treatment currently in place in the Southern Region of Ireland is likely to be successful.  相似文献   
83.
84.
HD-GYP is a protein domain of unknown biochemical function implicated in bacterial signaling and regulation. In the plant pathogen Xanthomonas campestris pv. campestris, the synthesis of virulence factors and dispersal of biofilms are positively controlled by a two-component signal transduction system comprising the HD-GYP domain regulatory protein RpfG and cognate sensor RpfC and by cell-cell signaling mediated by the diffusible signal molecule DSF (diffusible signal factor). The RpfG/RpfC two-component system has been implicated in DSF perception and signal transduction. Here we show that the role of RpfG is to degrade the unusual nucleotide cyclic di-GMP, an activity associated with the HD-GYP domain. Mutation of the conserved H and D residues of the isolated HD-GYP domain resulted in loss of both the enzymatic activity against cyclic di-GMP and the regulatory activity in virulence factor synthesis. Two other protein domains, GGDEF and EAL, are already implicated in the synthesis and degradation respectively of cyclic di-GMP. As with GGDEF and EAL domains, the HD-GYP domain is widely distributed in free-living bacteria and occurs in plant and animal pathogens, as well as beneficial symbionts and organisms associated with a range of environmental niches. Identification of the role of the HD-GYP domain thus increases our understanding of a signaling network whose importance to the lifestyle of diverse bacteria is now emerging.  相似文献   
85.
Sir William Osler was the preeminent internist of his time, who also worked as a pathologist for a considerable period during his career. Between 1876 and 1889, he performed nearly 1000 autopsies in Montreal, Quebec, and Philadelphia, Pa. Many authors concluded that Osler stopped performing autopsies once he moved to Baltimore, Md, because the autopsy service was organized under William Welch, the professor of pathology. However, this assertion has been contradicted by a recent biography of Dr Osler. To reexamine this issue, the autopsy records of The Johns Hopkins Hospital and relevant publications were examined. The evidence suggests that Dr Osler was an enthusiastic, and sometimes engaged, observer of Hopkins autopsies but that he did not function as an autopsy prosector.  相似文献   
86.
OBJECTIVE: We investigated patterns of use of alcohol and its clinical effects among cirrhotic subjects who participated in a randomized clinical trial comparing the efficacy of transjugular intravenous portosystemic shunt and distal splenorenal shunt.
METHODS: There were 132 cirrhotic subjects, 78 with alcoholic liver disease (ALD), who were followed for a median of 49 months (range 2–93 months). Alcohol use was assessed by patient questionnaire, with corroboration by family members.
RESULTS: Twenty-eight subjects (21%) were drinking at study entry and 60 subjects (45%) drank during follow-up. Heavy drinking (>4 drinks/day) was recorded in 25 ALD subjects, but in no non-ALD subjects ( P < 0.0001). Drinking by ALD subjects was associated with a 153% increase in gamma-glutamyl transpeptidase (GGT) ( P < 0.0001). The frequencies of death (46% vs 30%), ascites (33% vs 20%), encephalopathy (56% vs 42%), and variceal bleeding (11% vs 3%) were greater in the ALD group. In a Cox proportional hazards model only "ever heavy drinking" was associated with death ( P = 0.0099), while recent heavy drinking increased the hazard of variceal hemorrhage dramatically (odds ratio 10.85).
CONCLUSIONS: Whereas most cirrhotic subjects, alcoholic or not, did not drink during 5 yr of observation, heavy alcohol use occurred exclusively in ALD patients. Alcohol use by ALD subjects was associated with elevations in GGT and was linked to death and with rebleeding from shunt dysfunction.  相似文献   
87.
本文总结了用于预防和终止心房颤动的起搏器的类型。窦房结功能异常的病人,心室起搏与较高的心房颤动的发生率相关。有鉴于此,有心房颤动病史、因心动过缓而需要安装起搏器的病人,应该安装双腔或心房起搏生理性起搏器,而不应安装单腔的心室起搏器。  相似文献   
88.
In the mid-1980s, Mosmann, Coffman, and their colleagues discovered that murine CD4+ helper T-cell clones could be distinguished by the cytokines they synthesized. The isolation of human Th1 and Th2 clones by Romagnani and coworkers in the early 1990s has led to a large number of reports on the effects of Th1 and Th2 on the human immune system. More recently, cells other than CD4+ T cells, including CD8+ T cells, monocytes, NK cells, B cells, eosinophils, mast cells, basophils, and other cells, have been shown to be capable of producing "Th1" and "Th2" cytokines. In this review, we examine the literature on human diseases, using the nomenclature of type 1 (Th1-like) and type 2 (Th2-like) cytokines, which includes all cell types producing these cytokines rather than only CD4+ T cells. Type 1 cytokines include interleukin-2 (IL-2), gamma interferon, IL-12 and tumor necrosis factor beta, while type 2 cytokines include IL-4, IL-5, IL-6, IL-10, and IL-13. In general, type 1 cytokines favor the development of a strong cellular immune response whereas type 2 cytokines favor a strong humoral immune response. Some of these type 1 and type 2 cytokines are cross-regulatory. For example, gamma interferon and IL-12 decrease the levels of type 2 cytokines whereas IL-4 and IL-10 decrease the levels of type 1 cytokines. We use this cytokine perspective to examine human diseases including infections due to viruses, bacteria, parasites, and fungi, as well as selected neoplastic, atopic, rheumatologic, autoimmune, and idiopathic-inflammatory conditions. Clinically, type 1 cytokine-predominant responses should be suspected in any delayed-type hypersensitivity-like granulomatous reactions and in infections with intracellular pathogens, whereas conditions involving hypergammaglobulinemia, increased immunoglobulin E levels, and/or eosinophilia are suggestive of type 2 cytokine-predominant conditions. If this immunologic concept is relevant to human diseases, the potential exists for novel cytokine-based therapies and novel cytokine-directed preventive vaccines for such diseases.  相似文献   
89.
Latino Americans are a rapidly growing ethnic group in the United States but studies of glioblastoma in this population are limited. We have evaluated characteristics of 21,184 glioblastoma patients from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. This SEER data from 2001 to 2011 draws from 28% of the U.S. population. Latinos have a lower incidence of GBM and present slightly younger than non-Latino Whites. Cubans present at an older age than other Latino sub-populations. Latinos have a higher incidence of giant cell glioblastoma than non-Latino Whites while the incidence of gliosarcoma is similar. Despite lower rates of radiation therapy and greater rates of sub-total resection than non-Latino Whites, Latinos have better 1 and 5 year survival rates. SEER does not record chemotherapy data. Survivals of Latino sub-populations are similar with each other. Age, extent of resection, and the use of radiation therapy are associated with improved survival but none of these variables are sufficient in a multivariate analysis to explain the improved survival of Latinos relative to non-Latino Whites. As molecular data is not available in SEER records, we studied the MGMT and IDH status of 571 patients from a UCLA database. MGMT methylation and IDH1 mutation rates are not statistically significantly different between non-Latino Whites and Latinos. For UCLA patients with available information, chemotherapy and radiation rates are similar for non-Latino White and Latino patients, but the latter have lower rates of gross total resection and present at a younger age.  相似文献   
90.
ABSTRACT

Effective strategies are needed to address the health behaviors of older patients with diabetes. One approach is health coaching, the practice of health education and health promotion through a structured partnership designed to enhance well-being and facilitate the achievement of individuals’ health-related goals. The aim of this study was to describe the development of a pilot health coaching curriculum, investigate its effects on geriatric patient outcomes, and examine qualitative feedback by older patients and medical students to the curriculum. This mixed-methods study involved 29 first-year medical students randomly paired with 29 older adults with uncontrolled Type 2 diabetes. Health-related quality of life (HRQoL), stage of change movement, diabetes knowledge, locus of control, Body Mass Index (BMI), and glycosylated hemoglobin (HbA1c) were assessed. Focus groups were used to evaluate patients’ and medical students’ experiences. Results showed significant increases in patients’ HRQoL and stage of change for exercise improved significantly over time. There were no significant changes in stage of change for healthy diet and medication, diabetes knowledge, BMI, and HbA1c from baseline to end of study. Focus group data indicated positive responses by older patients and the medical students. A health coaching curriculum may improve patient outcomes and can provide medical students the skills needed to provide compassionate care for geriatric patients.  相似文献   
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