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41.
The mouse Y-specific DNA sequence pY2 was used as a probe for fluorescence in situ hybridization (FISH) to evaluate murine hematopoietic tissues after sex-mismatched bone marrow transplant (BMT). The pY2 probe was localized to the long arm of the Y chromosome on BM metaphases. Hybridization of pY2 in FISH of interphase cells from BM, spleen, and thymus after BMT was compared with Southern blot analysis; both methods gave comparable results. Only FISH was able to analyze post-BMT peripheral blood (PB) samples successfully, and provides a useful method for following engraftment status in the mouse on an ongoing basis.  相似文献   
42.
BACKGROUND: Bipolar disorder (BPD) is the Axis I disorder with the highest risk for coexisting substance use disorder. One explanation for this phenomenon is the 'self-medication hypothesis', which states that some patients experience improvement in psychiatric symptoms as a result of substance use. We thus investigated reasons for substance use and perceived substance-induced improvement in BPD symptoms among patients with current BPD and substance dependence. METHODS: A total of 45 patients received six monthly assessments; 21 also received integrated group therapy (IGT), focusing simultaneously on BPD and substance dependence, while 24 did not receive IGT. Patients reported at intake their current reasons for initiating substance use (including BPD symptoms) and the effects of substance use on those symptoms. RESULTS: Nearly all patients initiated substance use because of at least one BPD symptom, especially depression (77.8%) and racing thoughts (57.8%); most (66.7%) reported improvement in at least one BPD symptom as a result of substance use. Among patients reporting substance-induced improvement in BPD symptoms, those receiving IGT reported fewer days of drug use over the 6-month study period than those not receiving IGT; this difference was not significant among patients without substance-induced improvement in BPD symptoms. LIMITATIONS: The study is limited by its small sample size and by the potential inaccuracy of self-reports regarding the effects of substance use on mood. CONCLUSIONS: Substance dependent patients who report that substance use improves their BPD symptoms may benefit from treatment that focuses simultaneously on both disorders.  相似文献   
43.
44.
We have identified two cases of previously untreated, small lymphocytic lymphoma with extranodal involvement, which had a reciprocal translocation, t(11;18)(q21;q21), as the sole cytogenetic abnormality. These two cases are remarkably similar to two previously reported cases carrying this translocation with regard to clinical features, cytogenetic abnormality, histologic subtype, and immunophenotype. Molecular genetic analysis of these two cases revealed clonal gene rearrangement of the IGH locus but only germline configuration of the BCL2 oncogene at 18q21 when probes and conditions that usually identify BCL2 rearrangement in lymphomas were used. Lymphomas bearing an (11;18) rearrangement appear to make up a phenotypically identifiable subgroup. Identification of the genes at the translocation breakpoints will be important.  相似文献   
45.
The clinical and pathological features of carcinomas of the pancreas with DNA replication errors (RER+) have not been characterized. Eighty-two xenografted carcinomas of the pancreas were screened for DNA replication errors using polymerase chain reaction amplification of microsatellite markers. Cases with microsatellite instability in at least two markers of a minimum of five tested were considered RER+. RER status was correlated with histological appearance, karyotype of the carcinomas when available, K-ras mutational status, and patient outcome. Three (3.7%) of the eighty-two carcinomas were RER+. In contrast to typical gland-forming adenocarcinomas of the pancreas, all three RER+ carcinomas were poorly differentiated and had expanding borders and a prominent syncytial growth pattern. Neither a Crohn's-like lymphoid infiltrate nor extracellular mucin production were prominent. Ductal adenocarcinomas of the pancreas typically contain a mutant K-ras gene, yet all three RER+ carcinomas had wild-type K-ras. One of the three RER+ carcinomas was karyotyped and showed a near diploid pattern. All three of the RER+ tumors were removed via Whipple resection. One of the three patients is free of disease 16 months after pancreaticoduodenectomy, one is alive and free of tumor at 52 months but developed two colon carcinomas during this period, and the third died of pancreatic cancer at 4 months. None of the three patients had a family history of colorectal carcinoma. A review of the K-ras wild-type carcinomas in a previously characterized series of pancreatic carcinomas with known K-ras mutational status identified two additional cancers with poor differentiation, a syncytial growth pattern, and pushing borders. Both of the cancers were diploid and both patients were longterm survivors (over 5 years). The inclusion of such patients in previous prognostic studies of pancreas cancer may explain the failure of histological grade to be a predictor of prognosis. These data suggest that DNA replication errors occur in a small percentage of resected carcinomas of the pancreas and that wild-type K-ras gene status and a medullary phenotype characterized by poor differentiation, and expanding pattern of invasion, and syncytial growth should suggest the possibility of DNA replication errors in carcinomas of the pancreas.  相似文献   
46.
Thirty-six consecutively admitted psychiatric inpatients were orally administered the Beck and Zung depression scales. Wide Range Achievement Test reading scores also were obtained. The Beck and Zung correlated significantly (p .001) with Diagnostic and statistical manual of mental disorders (DSM-III; American Psychiatric Association, 1980) depression criteria. When the patients were subdivided by diagnosis (Depression and mixed Depression vs. others), and depression scores compared, only the Zung significantly differentiated the two groups (F = 12.51, p less than .001). When subdivided by reading scores, both high (grade level M = 8.7) and low (grade level M = 3.2) groups' Beck and Zung scores correlated equally well with the DSM-III criteria measure. This study substantiates the common practice of orally presenting written tests to low functioning patients most convincingly in the case of the Zung Depression Scale.  相似文献   
47.
Summary The relationships of VII and VIII cranial nerves and related arteries are reviewed in 26 preparations by microdissection techniques. These vessels may be grouped in large (AICA, PICA), medium (LA, SA, CSA, RPI) and small calibre (vasa nervorum, radicullar and medullar branches). The importance of these structures in acoustic neuroma surgery, vestibular neurectomy and cross-compression syndromes is discussed. Vascular loops and elongated arteries are normal structures present at birth.This work was supported by a grant from the AJ Roemmers Foundation  相似文献   
48.
This study was designed to develop a customized enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of Johne's disease (JD) in farmed deer. Two antigens were selected on the basis of their superior diagnostic readouts: denatured purified protein derivative (PPDj) and undenatured protoplasmic antigen (PpAg). ELISA development was based on the antigen reactivity of the immunoglobulin G1 (IgG1) isotype, which is a highly specific marker for mycobacterial disease seroreactivity in deer. Sensitivity estimates and test parameters were established using 102 Mycobacterium paratuberculosis-infected animals from more than 10 deer herds, and specificity estimates were determined using 508 uninfected animals from 5 known disease-free herds. A receiver-operated characteristic analysis determined that at a cut point of 50 ELISA units, there was a specificity of 99.5% and sensitivities of 84.0% with PPDj antigen, 88.0% with PpAg, and 91.0% when the antigens were used serially in a composite test. Estimated sensitivity was further improved using recombinant protein antigens unique for M. paratuberculosis, which identified infected animals that were unreactive to PPDj or PpAg. While 80% of animals that were seropositive in the IgG1 ELISA had detectable histopathology, the assay could also detect animals with subclinical disease. The test was significantly less sensitive (75%) for animals that were culture positive for M. paratuberculosis but with no detectable pathology than for those with pathological evidence of JD (>90%). When the IgG1 ELISA was used annually over a 4-year period in a deer herd with high levels of clinical JD, it eliminated clinical disease, increased production levels, and reduced JD-related mortality.  相似文献   
49.
The simian-human immunodeficiency virus (SHIV)/ macaque model for human immunodeficiency virus type 1 has become a useful tool to assess the role of Vpu in lentivirus pathogenesis. In this report, we have mutated the two phosphorylated serine residues of the HIV-1 Vpu to glycine residues and have reconstructed a SHIV expressing this nonphosphorylated Vpu (SHIV(S52,56G)). Expression studies revealed that this protein was localized to the same intracellular compartment as wild-type Vpu. To determine if this virus was pathogenic, four pig-tailed macaques were inoculated with SHIV(S52,56G) and virus burdens and circulating CD4(+) T cells monitored up to 1 year. Our results indicate that SHIV(S52,56G) caused rapid loss in the circulating CD4(+) T cells within 3 weeks of inoculation in one macaque (CC8X), while the other three macaques developed no or gradual numbers of CD4(+) T cells and a wasting syndrome. Histological examination of tissues revealed that macaque CC8X had lesions in lymphoid tissues (spleen, lymph nodes, and thymus) that were typical for macaques inoculated with pathogenic parental SHIV(KU-1bMC33) and had no lesions within the CNS. To rule out that macaque CC8X had selected for a virus in which there was reversion of the glycine residues at positions 52 and 56 to serine residues and/or compensating mutations occurred in other genes associated with CD4 down-regulation, sequence analysis was performed on amplified vpu sequences isolated from PBMC and from several lymphoid tissues at necropsy. Sequence analysis revealed a reversion of the glycine residues back to serine residues in this macaque. The other macaques maintained low virus burdens, with one macaque (P003) developing a wasting syndrome between months 9 and 11. Histological examination of tissues from this macaque revealed a thymus with severe atrophy that was similar to that of a previously reported macaque inoculated with a SHIV lacking vpu (Virology 293, 2002, 252). Sequence analysis revealed no reversion of the glycine residues in the vpu sequences isolated from this macaque. These results contrast with those from four macaques inoculated with the parental pathogenic SHIV(KU-1bMC33), all of which developed severe CD4(+) T cell loss within 1 month after inoculation. Taken together, these results indicate that casein kinase II phosphorylation sites of Vpu contributes to the pathogenicity of the SHIV(KU-1bMC33) and suggest that the SHIV(KU-1bMC33)/pig-tailed macaque model will be useful in analyzing amino acids/domains of Vpu that contribute to the pathogenesis of HIV-1.  相似文献   
50.
An experimental model of pulmonary fibrosis has been developed by dosing rats with one-fifth the LD50 dose of the herbicide paraquat on 5 consecutive days. Approximately 50% of the rats died within 4 days of the completion of dosing, showing macroscopic changes and wet weight increases in the lung consistent with severe oedema. Those animals which died between Days 4 and 10 had markedly increased levels of hydroxyproline in the lung, maximum at Day 6, and increased prolyl hydroxylase activity, maximum at Day 4. These changes, together with an increase in thymidine incorporation into DNA, and increased lung DNA content, were consistent with the development of fibrosis. Measurement of transglutaminase activity in the lung showed marked increases at Days 4 and 10 after completion of dosing. This activity paralleled closely the changes in prolyl hydroxylase activity and became increasingly associated with particulate protein present in the "nuclear pellet" fraction. The presence of zymogen plasma transglutaminase trapped in lung homogenates could not be demonstrated but the contribution by the active plasma transglutaminase (Factor XIIIa) to increases shown at Day 4 cannot be ruled out.  相似文献   
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