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41.
42.
A stability-indicating assay is described for the determination of N-acetylcysteine in aqueous pharmaceutical formulations. The sample is diluted to an appropriate concentration with dilute aqueous orthophosphoric acid. An aliquot of the solution, containing added l-tyrosine as an internal standard, is chromatographed using a 10-mum C(18) stationary phase with dilute orthophosphoric acid (pH 2.0) containing 0.5% w/v of sodium perchlorate as the mobile phase. The assay, which has a relative standard deviation of about 0.8%, can also be used as a test for related impurities in N-acetylcysteine. It is also suitable for determining the N-acetylcysteine content of the drug substance.  相似文献   
43.
At a superficial level, one might characterize the primary prevention debate as centering on the question of whether primary prevention has been demonstrated to be an effective means of promoting mental health. This interpretation is supported by the clarity and strength of the confident generalizations of primary prevention proponents such as Dr. Albee (We have a lot of evidence on the effectiveness of primary prevention ... it is available in the literature for all to read) and primary prevention critics such as Dr. Lamb (... The major functional mental illnesses, as well as the frequently occurring diagnosable minor illnesses, remain untouched by efforts to strengthen mental health.). However, it seems clear that the disagreement is not primarily a matter of differences in data interpretation (although this is clearly a part of the problem). Rather, it seems to be mostly a function of differences at the level of basic assumptions about the nature of mental illness and the appropriate scope of activity for mental health professionals.  相似文献   
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Studies on blood samples from a 30-year-old woman of Korean origin, her husband and children, showed the presence of the cis-AB genotype in the mother and one child. The cis-AB red cells showed abnormal reactions with both polyclonal and monoclonal anti-B reagents and an elevated level of H antigen. The serum contained weak anti-B that reacted with normal B antigen but not with that on cis-AB cells. Normal levels of A substance but reduced levels of B and H substances were present in the saliva. Conversely, the serum showed reduced A and normal B and H blood group transferase activity.  相似文献   
46.
A clone of human gastric cancer cells (AGS-6) and the parental line (AGS-P) from which it was isolated were used in cell survival studies to determine whether pretreatment for 24, 48 or 72h with -difluoromethylornithine (DFMO, 5mM) would increase the cell's sensitivity to 5-Fluorouracil (5FU), Adriamycin (Adria), 1-(2-chloroethyl)-3-(4-methyl cyclohexyl)-1-nitrosourea (MeCCNU), or Bleomycin (Bleo). Generally, the AGS parental cells were most sensitive to the anticancer agents after exposures to DFMO. However, there was no way to predict in advance from DFMO-induced changes in ornithine decarboxylase (ODC), polyamine or cell kinetics values, how long an exposure to DFMO was required before sensitization to an anticancer agent occurred. The degree of potentiation for a single drug was variable from time to time during exposure to DFMO, and broad differences in the sensitizations were demonstrated among the four anticancer drugs. The AGS-6 clone exhibited little or no increased sensitivity as a result of pretreatment with DFMO, even though the DFMO-induced reductions in ODC and polyamine values in these cells were similar to those produced in the more sensitive parental line.  相似文献   
47.
This analysis shows a definite trend of fiscal and social retrenchment policy by the government concerning in-home care service delivery (Tables 1 and 2). Ruggie (1990:164) notes that such shifts and changes in Medicare reimbursement patterns may be efforts of the government to realign itself to become the pivotal force in the provision or delivery of in-home care. Cost-containment pressures, although most needed in the health care industry, are the primary driving force behind retrenchment and the subsequent realignment of government. Such forces tend to impede the development of a comprehensive system for the provision of long-term care services. As noted, the movements and shifts in reimbursement patterns documented by this analysis can lead one to conclude that the same old features will continue to prevail instead of new and innovative delivery structures or public-private partnerships. In other words, the in-home care industry will become more like the nursing home industry--highly regulated and perpetually plagued by questions concerning quality of care. Although government is attempting to diminish its task as the prime provider of health services (i.e., through fiscal retrenchment) and the public's role as the dominant delivery system (i.e., social retrenchment), nevertheless the government has been unable to retrench politically in spite of its present direction of cost containment and fiscal restraint. Consequently, Ruggie (1990:147) notes that "the social welfare functions may continue to be performed" in spite of cost restraint policies. As a result, another "no care zone" is created and policy-makers will continue to develop "crisis policy" such as intense demands to hold unit costs low. The home care system has expanded many of the long-term care options and has emerged as a salient segment of our health and social service system (Applebaum and Phillips, 1990). Yet, policy-makers have not developed a comprehensive long-term care system, particularly one that defines a common policy for home care benefits and engenders the right kind of public-private partnership for the delivery of quality home care.  相似文献   
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The publication of the national service framework for mental health provides a good opportunity to review acute psychiatric services, which are unpopular with patients and understaffed. The framework recommends a balance of hospital beds, community provision and home care. Planning should usually cover one or more primary care groups.  相似文献   
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