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In this study we characterized the pattern of use of preventive therapies for specific respiratory diseases within a cohort of homosexual men and assessed the impact of targeted feedback on the level of compliance with guidelines for these diseases. All human immunodeficiency virus seronegative (HIV-) (n=169) and acquired immune deficiency syndrome (AIDS)-free human immunodeficiency virus seropositive (HIV+) (n=154) participants in our cohort, who completed four annual visits between October 1989 and December 1993, were identified. Information about the use of purified protein derivative (PPD) (tuberculin) testing, history of pneumococcal vaccinations, influenza vaccinations, use of Pneumocystis carinii pneumonia (PCP) prophylaxis, symptoms and CD4 counts was obtained yearly for each subject. In 1992, participating physicians were provided with feedback regarding the overall levels of compliance with contemporary guidelines for the prevention of respiratory disease. As part of this exercise, the guidelines were distributed and discussed. The percentage of HIV+ patients who underwent PPD testing increased from 43 to 65% during the study (p=0.001). Significantly more HIV+ than HIV- patients underwent PPD testing (p<0.001). A total of 144 (94%) HIV+ men received at least one influenza vaccination compared to 60 (35%) HIV- men (p<0.001). Utilization of influenza vaccination in the HIV+ group significantly increased from 78% in 1992 to 92% in 1993 (p<0.001). A total of 104 (68%) HIV+ men received pneumococcal vaccination compared to 2 (1%) HIV- men (p<0.001). Among HIV+ individuals whose absolute CD4+ count was less than 200 cells x mm(-3), the percentage of men who received primary PCP prophylaxis was 0, 86, 72 and 88 for the years 1990-1993, respectively. Among HIV+ patients whose only eligibility criterion for PCP prophylaxis was a CD4+ percentage <20%, compliance was 55, 30, 37 and 50% for the years 1990-1993, respectively. Among HIV+ subjects, increases in the compliance level were noted for all preventive therapies after targeted feedback was provided during the last quarter of 1992. However, only utilization of influenza vaccine exceeded a 90% compliance in 1993. These data demonstrate that a suboptimal level of compliance with current guidelines for the prevention of respiratory disease among human immunodeficiency virus-infected individuals can be significantly improved using targeted feedback. Although it is likely that similar effects could be achieved in other populations or the community at large, this remains to be demonstrated.  相似文献   
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Individual variability in the plasma concentration of a xenobiotic is a considerable problem in the clinical use as well as in the clinical development of a new drug. In clinics altered drug response and drug toxicity are predominant findings. In clinical development (especially in the early phases) problems with the interpretation of individual pharmacokinetics and appearance of unexpected drug reactions may occur. One major reason for the inter-and intraindividual variability is based on variations in the metabolism of the drug that are dependent on the genetic variations of the metabolising enzymes. However, while the first of these so-called polymorphisms has already been described in 1979 (for a review see [Daly 1995]) and knowledge of these polymorphisms are still growing, the impact on clinical practice as well on the selection and development of drug candidates in the pharmaceutical industry at present is still limited. This may change in the near future as recent advances in molecular biology and especially in the diagnosis of individual genomic characteristics will result in a better understanding of the basic principles of the polymorphisms. High throughput screening methods will reveal information on the distribution of these polymorphic alleles in the target population and enable the broad characterization of the drug candidate in in vitro systems. The early knowledge as to whether a polymorphic pathway is involved in drug metabolism/action and of its clinical relevance will lead to a reduction of time and costs in the development of a new drug.  相似文献   
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Distinct lipid compositions of intracellular organelles could provide a physical basis for targeting of membrane proteins, particularly where transmembrane domains have been shown to play a role. We tested the possibility that cholesterol is required for targeting of membrane proteins to the Golgi complex. We used insect cells for our studies because they are cholesterol auxotrophs and can be depleted of cholesterol by growth in delipidated serum. We found that two well-characterized mammalian Golgi proteins were targeted to the Golgi region of Aedes albopictus cells, both in the presence and absence of cellular cholesterol. Our results imply that a cholesterol gradient through the secretory pathway is not required for membrane protein targeting to the Golgi complex, at least in insect cells.  相似文献   
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Eighty-five cases of atypical schizophrenia were compared with 200 of schizophrenia, 100 of bipolar (mania), and 225 of unipolar (depression) affective disorder. Comparisons were made on the basis of sex, age at admission, precipitating factors, outcome, and a family history of schizophrenia or of affective disorder. The atypical schizophrenia differed remarkably from the schizophrenia and most closely resembled the bipolar affective disorder when allowance was made for a younger age at onset and a higher frequency of precipitants. An analysis of symptoms verified the predominance of schizophrenic features in the atypical schizophrenia, but also showed a high percentage (80%) of patients who had one or more manic symptoms at index admission. It is concluded that great care should be taken in diagnosing schizophrenia in a patient who also has manic symptoms.  相似文献   
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