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91.
OBJECTIVE: This study determined the sources and frequency of diagnostic uncertainty for patients with chronic psychosis and active cocaine abuse or dependence and assessed the usefulness of prospective follow-up in clarifying diagnosis. METHODS: A total of 165 male patients with chronic psychoses and cocaine abuse or dependence on inpatient units of a Veterans Affairs medical center were evaluated using the Structured Clinical Interview for DSM-III-R (SCID-R), urine tests, hospital records, and interviews with collateral sources. An algorithm allowing key SCID-R items and diagnostic criteria to be designated as provisionally met or uncertain was applied, resulting in a provisional diagnosis and a list of alternate diagnoses. The assessment was repeated 18 months later in an attempt to resolve diagnostic uncertainty. RESULTS: In 30 cases (18 percent), initial assessment produced a definitive diagnosis, including 21 cases of schizophrenia, six of schizoaffective disorder, and three of psychostimulant-induced psychotic disorder. In the other 135 cases, a definitive diagnosis could not be reached because of one or more sources of diagnostic uncertainty, including insufficient periods of abstinence (78 percent), poor memory (24 percent), and inconsistent reporting (20 percent). Reassessment at 18 months led to definitive diagnoses in 12 additional cases. CONCLUSIONS: It was frequently difficult to distinguish schizophrenia from chronic substance-induced psychoses. Rather than concluding prematurely that psychotic symptoms are, or are not, substance induced, clinicians should initiate treatment of both psychosis and the substance use disorder in uncertain cases. The persistence or resolution of psychosis during abstinence and additional history from the stabilized patient or collateral sources may clarify the diagnosis.  相似文献   
92.
Salvia divinorum is a vision-inducing mint used by the Mazatec people of Oaxaca, Mexico. It is grown in California and other parts of the United States where it is employed as a legal hallucinogen. Traditional opinion has been that the plant has mild psychotropic activity, at best. However, when ingested in the correct manner, it is quite powerful. The fresh leaves are chewed as a quid and kept in the mouth. They may also be eaten raw or prepared as an aqueous infusion. When dried, they are smoked in the manner of marijuana. The neoclerodane diterpene, salvinorin A (also known as divinorin A), has been demonstrated in animals and humans to be its major active ingredient. Essentially inactive if taken orally, the compound is effective in doses of 200 to 500 mcg when smoked in a manner similar to cocaine free base. This makes salvinorin A the first documented diterpene hallucinogen and the most potent naturally occurring hallucinogen thus far isolated. This is somewhat remarkable, since the compound is not an alkaloid. This article reviews the use of S. divinorum and its chemistry. In addition, it discusses the effects of the plant and salvinorin A in animals and humans, as well as their potential to become drugs of abuse.  相似文献   
93.
BACKGROUND: Significant changes are restructurng the U.S. health care delivery system. National health reform is now extending itself into the public sector. Increased health and medical costs by federal and state governments are forcing a reevaluation of major entitlement programs, especially Medicaid. METHODS/RESULTS: Because Medicaid is the single largest item in many state budgets, states are now enrolling Medicaid patients into managed and coordinated care arrangements as a means to control costs and increase access to care. HMOs are not only competing for private patients but also actively seeking the Medicaid population. Nationally, almost one-fourth of all Medicaid patients are now enrolled in managed care plans. Various models and approaches have been developed by individual states. CONCLUSIONS: Because managed care enrollment in the Medicaid program has increased substantially in recent years, selected services including vision care are no longer rendered by any practitioner willing to accept Medicaid fees. Freedom of choice is now restricted to pre-selected and panel practitioners participating with the managed care program. The rules, regulations, billing procedures, fees, and program requisites will differ under managed care programs. Private optometric practitioners must consider entering economic and organizational relationships and linkages that make them attractive to managed care organizations.  相似文献   
94.
We isolated cDNA clones encoding five S-RNases (S1-, S3-, S5-, S6-, S7-RNases) from pistils of Pyrus pyrifolia (Japanese pear), a member of the Rosaceae. Their amino acid sequences were aligned with those of other rosaceous S-RNases sequenced so far. A total of 76 conserved amino acid residues were stretched throughout the sequence, but were absent from the 51-66 region which was designated the hypervariable (HV) region. The phylogenetic tree of rosaceous S-RNases showed that S-RNase polymorphism predated the divergence of Pyrus and Malus. Pairwise comparison of these S-RNases detected two highly homologous pairs, P. pyrifolia S1- and S4-RNases (90.0%) and P. pyrifolia S3- and S5-RNases (95.5%). The positions of amino acid substitutions between S1- and S4-RNases were spread over the entire region, but in the pair of S3- and S5-RNases, amino acid substitutions were found in the 21-90 region including the HV region. The substitutions in this restricted region appear to be sufficient to discriminate between S3 and S5 pollen and to trigger the self-incompatible reaction.  相似文献   
95.
The behavioral effects were studied of monoclonal antibodies (MA) against A3G7 protein, which is known to be associated with the processes of nervous cell differentiation. Elaboration, storage, and retention of acoustic startle (ASR) habituation and freezing behavior were tested in adult rats. The MA applied in a dose of 50 ng on cerebellar vermis selectively impaired only the ASR long-term habituation storage whereas its dose of 5 mcg impaired both long-term habituation storage and fear-conditioned freezing. Application of 10 mcg of MA disrupted the elaboration and storage of the ASR short- and long-term habituation as well as fear-conditioned freezing. The results are considered as experimental verification of systemogenesis theory and hypothesis about a common molecular basis of learning and development.  相似文献   
96.
In the Netherlands, childhood leukaemia is recorded by the Dutch Childhood Leukaemia Study Group (DCLSG, set up in 1972) and by nine regional cancer registries which together form the Netherlands Cancer Registry (NCR, set up in 1989). The data files from the incidence years 1989-1992 of the two registries were linked in order to evaluate accuracy and completeness and to calculate and equalise the incidence rates for childhood leukaemia in The Netherlands. Unlinked records or records with disagreements (birth date, sex, type of leukaemia and incidence date) were checked by the DCLSG and by the regional cancer registries. The DCLSG recorded 431 cases of childhood leukaemia, while the NCR recorded 434 cases. After record linkage and review of the cases, it was concluded the 445 records should have been recorded as childhood leukaemia. The NCR had recorded 425 of the 445 correct cases (95.5%), but had missed 20 cases (4.5%). The DCLSG had recorded 431 of the 445 correct cases (96.9%) and had missed 14 cases (3.1%). In addition, the NCR had recorded 9 cases incorrectly as childhood leukaemia. Part of the disagreement was caused by differences in coding rules (definition of non-Hodgkin's lymphoma (NHL) and the myelodysplastic syndrome versus leukaemia). It could be concluded that the quality and completeness of the two registries was very high. Regular comparison of the recorded data will help to reveal the inherently problematic disagreement between definitions and coding.  相似文献   
97.
Cypermethrin is a synthetic pyrethroid that belongs to a group of insecticides with low mammalian toxicity but high insecticidal activity. The present study was designed to investigate the toxicity of cypermethrin on freshly isolated hepatocytes from male and female rats. Hepatocytes were harvested by a collagenase perfusion technique and were exposed to different concentrations of cypermethrin (100, 200, 400, or 800 ng/2 x 10(6) cells) for up to 2 h. Cell viability and the leakage of aspartate transaminase (AST) and alanine transaminase (ALT) were determined throughout the incubation period. The cell viability of the hepatocytes from male and female rats exposed to 400 ng and 800 ng was significantly reduced after 60 and 30 min of incubation, respectively. With cells from female rats, viability was also reduced upon exposure to 200 ng cypermethrin for 2 h. The decrease in cell viability was dose and time dependent. The leakage of ALT and AST was significantly increased with 400 and 800 ng concentrations at 60 and 30 min, respectively. ALT leakage from female hepatocytes was significantly increased at 60 min of incubation with the 200-ng dose, whereas 2 h of incubation was required for the leakage of ALT from the cells of male rats. The present data indicate that cypermethrin has toxic effects on male and female rat hepatocytes in a dose- and time-dependent manner. The data suggest that female rat hepatocytes may be more sensitive to the toxic effects of cypermethrin than male cells.  相似文献   
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100.
This study demonstrates that endogenously produced interferon gamma (IFN-gamma) forms the basis of a tumor surveillance system that controls development of both chemically induced and spontaneously arising tumors in mice. Compared with wild-type mice, mice lacking sensitivity to either IFN-gamma (i.e., IFN-gamma receptor-deficient mice) or all IFN family members (i.e., Stat1-deficient mice) developed tumors more rapidly and with greater frequency when challenged with different doses of the chemical carcinogen methylcholanthrene. In addition, IFN-gamma-insensitive mice developed tumors more rapidly than wild-type mice when bred onto a background deficient in the p53 tumor-suppressor gene. IFN-gamma-insensitive p53(-/-) mice also developed a broader spectrum of tumors compared with mice lacking p53 alone. Using tumor cells derived from methylcholanthrene-treated IFN-gamma-insensitive mice, we found IFN-gamma's actions to be mediated at least partly through its direct effects on the tumor cell leading to enhanced tumor cell immunogenicity. The importance and generality of this system is evidenced by the finding that certain types of human tumors become selectively unresponsive to IFN-gamma. Thus, IFN-gamma forms the basis of an extrinsic tumor-suppressor mechanism in immunocompetent hosts.  相似文献   
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