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71.
Vascular endothelial growth factor (VEGF) is a potent angiogenic factor. VEGF gene therapy improves perfusion of ischemic myocardium in experimental models and possibly in patients with end-stage coronary artery disease. In addition to its proliferative and migratory effect on endothelial cells, it also activates and up-regulates endothelial nitric oxide synthase (eNOS). Therefore, the authors investigated coronary endothelium-dependent vasodilatation in patients before and after VEGF gene therapy. The effect of intracoronary acetylcholine infusion on coronary diameter was assessed at baseline and after 3 months follow-up in patients with end-stage coronary artery disease treated with VEGF gene and in controls scheduled for elective percutaneous transluminal coronary angioplasty (PTCA) (acetylcholine test at diagnostic angiography and before a subsequently scheduled PTCA). Five out of six VEGF patients experienced a reduction in anginal complaints. Angiographic evidence for improved collateral filling was evident in two out of six patients. The vasoconstrictive response to acetylcholine was partly converted into dilatation. In contrast, the acetylcholine response in control patients remained vasoconstrictive. In conclusion, VEGF gene therapy has an important beneficial effect on the functional characteristics of the myocardial vascular network. Therefore, this therapy can potentially play an important role in all stages of the atherosclerotic process.  相似文献   
72.
Quality assurance issues have assumed growing importance in the cytology laboratory. The 1988 Clinical Laboratories Improvement Amendment (CLIA '88) (United States Department of Health and Human Services, Federal Register: U.S. Government Printing Office 1990;55:9495) regulates the patient identifiers and clinical data on the requisition form but does not mandate physician compliance to provide the information. We investigated the use of patient identifiers and clinical data by laboratories as specimen acceptance/rejection criteria. We surveyed 81 board certified cytopathologists and 235 randomly selected cytology laboratories for acceptance criteria of cytology specimens and received responses from 104. Approximately two thirds of all responding laboratories had specific criteria for rejecting specimens on the basis of inadequate identification or clinical data. While the vast majority required the specimens to be identified with patient name, collection date, and specimen source, a minority of laboratories required clinical information such as LMP, prior atypical cytologic/histologic specimens, and history of previous therapy. Little correlation was found between practice setting and the use of rejection criteria. Diagn Cytopathol 1994; 11:85–92. © 1994 Wiley-Liss, Inc.  相似文献   
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OBJECTIVE: It has been suggested that keratinocyte (KC) stem cells reside at the epicenter of a clonal population of cells. To estimate the territory or surface area covered by a single stem-cell-derived KC population in human skin, clonal skin maps were created from 3 healthy adult women and from normal skin of a psoriatic patient. DESIGN: Two hundred fifty-eight punch biopsy samples of various sizes (ranging from 2 to 8 mm in diameter) were analyzed for clonality employing X chromosome inactivation patterns at the human androgen receptor gene (HUMARA) locus. DNA was isolated and clonality established by significant decrease of either maternal or paternal X chromosome band patterns following restriction enzyme digestion, polymerase chain reaction amplification, and gel electrophoresis. RESULTS: Fifty-three (41%) of 128 two-mm biopsies were clonal, whereas only 6 (14%) of 43 three-mm, 5 (14%) of 36 four-mm, and 3 (8%) of 35 five-mm biopsies revealed a clonal population of KCs. By contrast, in 5 different biopsies from a psoriatic patient, including 4- or 5-mm sizes, all but 1 were clonal; even an 8-mm biopsy contained a clonal population of KCs. Mantel-Haenszel chi(2) analysis revealed a P value of.001, reflecting a strong trend in probability for presence of a single clone of KCs as related to size of the biopsy sample. By sequentially analyzing 30 contiguous 2-mm biopsy samples within a given strip of skin, 10 clonal domain changes, as reflected in maternal versus paternal switches, were observed. CONCLUSIONS: These results provide direct evidence of a clonal population of KCs in normal and psoriatic lesion-free skin, and indicate that a clonal epidermal unit of KCs frequently can be detected in small biopsies (2 mm), but that in normal skin sampling, overlapping clones are apparently present in larger (ie, 4-5-mm) biopsies, producing nonclonal patterns. The clonal domain of progeny in normal skin has a rather limited territorial boundary (2 mm in diameter). However, in lesion-free skin from a psoriatic patient, there may be clonal expansion of KCs due to perturbation in epidermopoiesis and/or stem cell distribution.  相似文献   
74.
Mycoplasma organisms were readily recognized in samples of milk or udder secretions from cows with clinical Mycoplasma bovis mastitis when these samples were stained with 0.01% acridine orange at pH 3.0. Samples could be stored at -4 degrees C for several days or subjected to repeated freezing and thawing without loss of staining or fluorescence properties. Use of this procedure in diagnostic laboratories on suspect samples from cows with clinical mastitis could hasten inauguration of control measures against this highly contagious disease by several days; however, definitive diagnosis still requires standard culture methods.  相似文献   
75.
Summary Background: The World Health Organization predicts that by 2012, depression will be the number one disease in the world. Thus, many women who become pregnant will require treatment with antidepressants. We are aware that women and their health care providers remain hesitant to prescribe and take these drugs during pregnancy, despite evidence of the relative safety. Objectives: 1) To determine perception of risk of antidepressant drugs by pregnant women with depression, 2) to determine the efficacy of evidence-based counseling, and 3) to identify determinants that influence women in their decision making regarding the continuation/discontinuation of antidepressants during pregnancy. Methods: Women who called The Motherisk Program requesting information about the safety of an antidepressant during pregnancy were compared with two other groups: 1) Women who called about antibiotic use (i.e., non-teratogenic drugs used short-term) and 2) women who called about gastric medications (i.e., non-teratogenic drugs used long-term). Their perception of risk was measured before and after evidenced-based information was given and determinants of decision making was also evaluated. Results: We recruited 100 women taking antidepressants during pregnancy and 100 in each comparison group. Despite receiving evidence-based reassuring information, 15% of antidepressant users, compared to 4% using gastric drugs and 1% using antibiotics, chose to discontinue their medication. The main determinants of decision making were based on: information received prior to calling Motherisk, family and friends advice, the internet, sequence of advice given and if a women was undecided at the time of call. Conclusions: Women continue to fear taking antidepressants during pregnancy, more so than non psychiatric drugs, however, evidence based counseling can lower this fear, although not totally. Deciding whether to continue to take a medication or not during pregnancy, is a complex decision for women and their healthcare providers to make.  相似文献   
76.
In 1997, the Schools of Medicine and Public Health at the University of North Carolina at Chapel Hill (UNC) developed a formal MD-MPH program, called the Health Care and Prevention (HC&P) Program, located in the Public Health Leadership Program in the UNC School of Public Health. Since then, and especially since 2003, the number of UNC medical students taking a year out of their medical studies to pursue an MPH has increased dramatically. At present, more than 20% of UNC medical students enter an MPH program at some point between entering medical school and leaving for residency.The HC&P Program is designed to introduce clinicians to the population sciences and to create physicians who can think in both individual and population terms. The curriculum is a rigorous, 12-month program that includes a practicum experience and a master's paper. Several of the traditional MPH introductory courses have been redesigned to be more relevant to physicians. The program allows a maximum number of electives and places a value on flexibility so that students, together with faculty, can design the educational experience that best meets their needs. Many members of the faculty of the program themselves have both MD and MPH degrees, and some have dual appointments in the schools of medicine and public health.The authors have begun a longitudinal cohort study of program graduates and other medical graduates to understand the effect of the program on students' perceptions of their competency and their ability to exert leadership in various areas of population health.  相似文献   
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α-Amino-iso-butyrate (AIB) inhibits long-term, protein synthesis-dependent memory formation by reducing labelled leucine uptake in vivo without affecting leucine incorporation into protein. Unlike the antibiotic cycloheximide, AIB does not block long-term memory formation through inhibition of protein synthesis per se. The behavioural effect of AIB is restricted to times of administration between 5 min before and 5 min after learning a single trial passive avoidance task by day-old chickens. It is concluded that (1) AIB competes with normal amino acids for uptake into cells, and (2) the uptake of amino acids for protein synthesis specific to long-term memory formation takes place in the first few minutes following learning.  相似文献   
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