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1.
Successful efforts in improving breastfeeding initiation rates at an urban teaching hospital prompted the hospital to create a lactation consultant (LC) position in the outpatient setting to focus on breastfeeding duration. This article reviews the complexity of the clinic setting, with the challenges and benefits of the consultant's first year in one of the hospital's outpatient clinics. Preliminary data collected by the consultant suggest that patients counseled by the LC in the outpatient clinic setting have longer breastfeeding duration rates.  相似文献   
2.
The etiology of cardiac allograft vasculopathy is not known, but may be preceded by both endothelial cell and smooth muscle dysfunction of the epicardial coronary arteries. We here report a case of acute, reversible coronary artery vasospasm which caused a myocardial infarction in a cardiac transplant recipient. The patient had a complex post-transplant course, including an episode of severe vascular rejection several months before this presentation. Interestingly, the event was captured in its early stages because the patient presented with chest pain: a rare event because of the denervation of the transplanted heart. Our ability to document the etiology of this patient's myocardial infarction supports the concept that cardiac allograft vasculopathy is a progressive disease that, in its early stages, may include a reversible component of abnormal vasoreactivity.  相似文献   
3.

Objective: To summarize changes in folic acid awareness, knowledge, and behavior among women of childbearing age in the United States since the U.S. Public Health Service (USPHS) 1992 folic acid recommendation and later fortification. Methods: Random-digit dialed telephone surveys were conducted of approximately 2000 women (per survey year) aged 18–45 years from 1995–2005 in the United States. Results: The percentage of women reporting having heard or read about folic acid steadily increased from 52% in 1995 to 84% in 2005. Of all women surveyed in 2005, 19% knew folic acid prevented birth defects, an increase from 4% in 1995. The proportion of women who reported learning about folic acid from health care providers increased from 13% in 1995 to 26% in 2005. The proportion of all women who reported taking a vitamin supplement containing folic acid increased slightly from 28% in 1995 to 33% in 2005. Among women who were not pregnant at the time of the survey in 2005, 31% reported taking a vitamin containing folic acid daily compared with 25% in 1995. Conclusions: The percentage of women taking folic acid daily has increased modestly since 1995. Despite this increase, the data show that the majority of women of childbearing age still do not take a vitamin containing folic acid daily. Health care providers and maternal child health professionals must continue to promote preconceptional health among all women of childbearing age, and encourage them to take a vitamin containing folic acid daily.

  相似文献   
4.
Summary Between 1955 and 1986, 25 children (aged 2 weeks to 15 years) were treated for intracranial ependymoma at M.D. Anderson Cancer Center. Nine patients had supratentorial primaries (5 high-grade, 4 low-grade), and 16 had infratentorial primaries (9 high-grade, 7 low-grade). Five patients had gross complete resection and 20 had incomplete resection. Seven patients received craniospinal irradiation (25–36 Gy to the neuroaxis, 45–55 Gy to tumor bed), 12 received local field irradiation (29–60 Gy, median 50 Gy). Five infants had adjuvant chemotherapy without radiotherapy, and 6 children had postradiotherapy adjuvant chemotherapy, and 12 patients had salvage chemotherapy with various agents and number of courses. Eight patients are alive, disease-free and without relapse from 1 year to 12 1/2 years from diagnosis (median 42 months). The primary failure pattern was local recurrence. The data suggest that 1) the long-term cure rate of children with ependymoma is suboptimal; 2) histologic grade may be of prognostic importance for supratentorial tumors; 3) prognosis appears worse for girls and infants under 3 years of age; 4) in well-staged patients routine spinal irradiation could be omitted; 5) the role of adjuvant chemotherapy is unclear. Address for offprints: Shiao Y. Woo, Department of Radiation Oncology, 6565 Fannin, M.S. DB1-37, Houston, Texas 77030, USA  相似文献   
5.
We examined gliding motility and cell invasion by an early-branching apicomplexan, Cryptosporidium parvum, which causes diarrheal disease in humans and animals. Real-time video microscopy demonstrated that C. parvum sporozoites undergo circular and helical gliding, two of the three stereotypical movements exhibited by Toxoplasma gondii tachyzoites. C. parvum sporozoites moved more rapidly than T. gondii sporozoites, which showed the same rates of motility as tachyzoites. Motility by C. parvum sporozoites was prevented by latrunculin B and cytochalasin D, drugs that depolymerize the parasite actin cytoskeleton, and by the myosin inhibitor 2,3-butanedione monoxime. Imaging of the initial events in cell entry by Cryptosporidium revealed that invasion occurs rapidly; however, the parasite does not enter deep into the cytosol but rather remains at the cell surface in a membrane-bound compartment. Invasion did not stimulate rearrangement of the host cell cytoskeleton and was inhibited by cytochalasin D, even in host cells that were resistant to the drug. Our studies demonstrate that C. parvum relies on a conserved actin-myosin motor for motility and active penetration of its host cell, thus establishing that this is a widely conserved feature of the Apicomplexa.  相似文献   
6.
Staphylococcus aureus isolates (n = 70) from 65 patients (36 canine, 18 equine, 7 bovine, 2 avian, and 2 feline) at seven veterinary teaching hospitals in the United States were studied. The majority of patients (83%) with an S. aureus infection were canine and equine, but this may have reflected a sample bias based on clinic case loads and diagnostic lab submissions at the participating institutions. Fourteen percent of patients with an S. aureus infection were infected with a methicillin-resistant S. aureus (MRSA) isolate. Six of seven institutions had at least one MRSA infection during the study. Pulsed-field gel electrophoresis on 63 of the 70 isolates yielded 58 unique strains of S. aureus. None of the strain types of the MRSA isolates matched each other or the type of any other S. aureus isolate. The proportions of patients infected with an MRSA isolate were not significantly different between institutions or animal species (P > or = 0.222). Methicillin-resistant S. aureus isolates in this study seemed to be community acquired rather than hospital acquired.  相似文献   
7.
Although accurate in the identification of Mycobacterium species, partial 16S rRNA gene sequencing does not distinguish Mycobacterium chelonae from M. abscessus. Thus, we designed a SmartCycler PCR assay targeting the 16S-to-23S internal transcribed spacer (ITS) region with use of MGB Eclipse probes to distinguish each species. Comparison with PCR-restriction enzyme analysis of a 441-bp fragment of the hsp65 gene resulted in 100% correlation with 25 isolates of M. chelonae and 25 isolates of M. abscessus. ITS PCR performed on 90 consecutive isolates identified by partial 16S rRNA gene sequencing (26 isolates of the M. chelonae-M. abscessus complex and 64 remaining isolates, including Mycobacterium species, Nocardia species, and other aerobic actinomycetes) showed 100% specificity and sensitivity. The ITS PCR assay is accurate and specific, easy to perform, and a good supplemental test when using partial 16S rRNA gene sequencing to identify M. chelonae and M. abscessus.  相似文献   
8.
9.
The cotton rat represents the best or only animal model for a large number of human infectious diseases, and it may be unique among small laboratory animals in its susceptibility to several potential agents of bioterrorism. Although the cotton rat is a reliable model to define pathologic changes produced during infection with human pathogens, the lack of specific reagents has precluded a more extensive analysis of the molecular basis of pathogenesis. Here, we report the cloning of 24 cotton rat genes encoding various cytokines, chemokines, and interferons (IFNs). Analysis of the expression of most of these genes was performed by RT-PCR in cotton rat macrophages during treatment with lipopolysaccharide (LPS) and in cotton rat lungs after infection with influenza virus. The availability of these reagents will provide the tools for molecular analysis of pathogenesis and immune responses to a wide variety of pathogens and set the basis for the development of new prophylactic and therapeutic strategies against human infectious diseases.  相似文献   
10.
Expression of clinical findings of Waardenburg syndrome type 1 (WS1) and type 2 (WS2) is extremely variable. Using our collection of 26 WS1 and 8 WS2 families, we analyzed the occurrence, severity, and symmetry of clinical manifestations associated with WS. We found significant differences between WS1 and WS2 in deafness, and in pigmentary and craniofacial anomalies. Factor analysis was used to identify manifestations which covaried, resulting in 2 orthogonal factors. Since mean factor scores were found to differ when compared between WS1 and WS2, we suggest that these factors could be useful in distinguishing WS types. We found that the WS gene was transmitted from mothers more often than from fathers. We also extensively examined the W-Index, a continuous measure of dystopia canthorum. Our data suggest that use of the W-Index to discriminate between affected WS1 and WS2 individuals may be problematic since 1) ranges of W-Index scores of affected and unaffected individuals over-lapped considerably within both WS1 and WS2, and 2) a considerable number of both affected and unaffected WS2 individuals exhibited W-index scores consistent with dystopia canthorum. Misclassification of families may have implications for risk assessment of deafness, since WS2 families have been reported to have greater incidence of deafness, as confirmed in our study. © 1995 Wiley-Liss, Inc.  相似文献   
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