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1.
Data collected from 25 cases of fetal or newborn death associated with maternal cocaine use are reported. The average week of gestation at which fetal death occurred was week 30. Abruptio placentae was observed in 7 cases and placental infarct was found in 4 cases. The average fetal blood cocaine and benzoylecgonine levels were 0.26 and 1.73 micrograms/mL. The average maternal levels were 0.14 and 1.80 micrograms/mL, respectively.  相似文献   
2.
Anti-idiotypes in B-cell tumor therapy   总被引:3,自引:0,他引:3  
Thirteen patients with B-cell lymphomas were treated with mouse monoclonal anti-idiotype antibodies. All but 1 of the patients in this study had received extensive prior treatment with conventional therapy for lymphoma. The treatment protocol initially included an escalating dose schedule which was intended to help us evaluate toxicity and pharmacokinetics and, eventually, to achieve appreciable levels of free mouse antibody in the circulation. The last 4 patients received substantial initial doses. Tumor sampling was performed before and during therapy for evaluation of tissue penetration by antibody. Patients received antibodies of gamma 1, 2a, or 2b isotype. None of the patients had serum paraproteins by routine clinical testing, but 6 had an idiotype protein detectable by a sensitive immunoassay at levels greater than 1 microgram/ml, two of which were greater than 200 micrograms/ml. These levels were temporarily reduced by plasma-pheresis. However, the presence of serum idiotype increased the requirement for mouse antibody to achieve tumor penetration. Another obstacle to treatment was immune response to mouse Ig that occurred in 5 of the 13 patients. Once an immune response had begun, further infusions of antibody failed to reach the tumor or induce tumor regression and were associated with toxicity. Our initial patient remains in an unmaintained complete remission 50 months after receiving antibody. Six of 12 additional patients have had objective remissions which also were clinically significant. However, these remissions were not complete. This therapy shows promise as an alternative modality for the treatment of B-cell lymphoma. We will need further studies to determine the mechanisms of the antitumor effect and to improve the clinical results.  相似文献   
3.
The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control.  相似文献   
4.
Invasion of human immunodeficiency virus (HIV) into the central and peripheral nervous system produces a wide range of neurological symptoms, which continue to persist even with adequate therapeutic suppression of the systemic viremia. The development of therapies designed to prevent the neurological complications of HIV require a detailed understanding of the mechanisms of virus penetration into the nervous system, infection, and subsequent neuropathogenesis. These processes, however, are difficult to study in humans. The identification of animal lentiviruses similar to HIV has provided useful models of HIV infection that have greatly facilitated these efforts. This review summarizes contributions made from in vitro and in vivo studies on the infectious and pathological interactions of feline immunodeficiency virus (FIV) with the nervous system. In vivo studies on FIV have provided insights into the natural progression of CNS disease as well as the contribution of various risk factors. In vitro studies have contributed to our understanding of immune cell trafficking, CNS infection and neuropathogenesis. Together, these studies have made unique contributions to our understanding of (1) lentiviral interactions at the blood–cerebrospinal fluid (CSF) barrier within the choroid plexus, (2) early FIV invasion and pathogenesis in the brain, and (3) lentiviral effects on intracellular calcium deregulation and neuronal dysfunction. The ability to combine in vitro and in vivo studies on FIV offers enormous potential to explore neuropathogenic mechanisms and generate information necessary for the development of effective therapeutic interventions.  相似文献   
5.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant.  相似文献   
6.
Image-directed percutaneous biopsies with a biopsy gun   总被引:3,自引:0,他引:3  
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method.  相似文献   
7.
Sera from leprosy patients and controls were assayed for immunoglobulin M (IgM) and IgG antibodies to the Mycobacterium leprae-specific phenolic glycolipid I antigen (PG) by enzyme-linked immunosorbent assay, for IgG antibodies to M. leprae protein antigens by Western immunoblot, and for antibodies to a 65-kilodalton (kDa) protein antigen of M. leprae by a competition antibody binding assay. Elevated levels of anti-PG IgM were seen in lepromatous and borderline lepromatous patients, and elevated levels of anti-PG IgG were seen in borderline lepromatous patients. There was a significant correlation between the bacillary index (BI) and anti-PG IgM whether all leprosy patients or only multibacillary patients were analyzed. A significant correlation was seen between anti-PG IgG and BI when all leprosy patients were used for analysis, but not when only multibacillary patients were used. IgG antibodies to protein antigens of M. leprae, as detected by Western immunoblot, were more prevalent in lepromatous and borderline lepromatous patients than in borderline tuberculoid patients, while one of eight controls showed one weak band. There were significant correlations between the number of M. leprae protein antigens detected by the sera of patients and both BI and the level of anti-PG IgM. The 65-kDa competition antibody binding assay detected active multibacillary leprosy. Patients positive for antibody to the 65-kDa antigen had a significantly higher BI and levels of anti-PG IgM and anti-PG IgG than did patients that were negative. In addition, the level of antibody to the 65-kDa antigen correlated with both the BI and anti-PG IgM. We conclude that testing for antibodies to protein antigens of M. leprae may provide a useful adjunct to testing for antibodies to PG.  相似文献   
8.
The stem cells of rapidly renewing tissues give rise to transiently proliferating cells, which in turn give rise to postmitotic terminally differentiated cells. Although the existence of a transiently proliferating compartment has been proposed for the prostate, little molecular anatomical evidence for its presence has been obtained to date. We used down-regulation of the cyclin-dependent kinase inhibitor p27Kip1 to identify cells capable of entering the proliferative phase of the cell cycle and, therefore, competent to fulfill the role of the transiently proliferating compartment. We examined the expression of p27Kip1 in relation to its role in the development of prostatic carcinoma. Formalin-fixed paraffin-embedded specimens from matched samples of normal-appearing prostate tissue, benign prostatic hyperplasia, high-grade prostatic intraepithelial neoplasia, primary adenocarcinomas, and pelvic lymph node metastases were evaluated by comparative immunohistochemistry against p27Kip1. In normal-appearing prostate epithelium, moderate to strong nuclear staining of p27Kip1 was present in greater than 85% of the terminally differentiated secretory cells. The normal basal cell compartment, believed to contain prostatic stem cells, showed distinctive p27Kip1 expression; acini in epithelial benign prostatic hyperplasia tissue contained more p27Kip1-negative basal cells than acini from non-benign prostatic hyperplasia tissue. A third layer of cells was identified that was sandwiched between the basal cells and the luminal cells, and this layer was consistently p27Kip1 negative. This intermediate layer was accentuated in the periurethral region, as well as in prostate tissue that had been subjected to prior combined androgen blockade. We hypothesize that, on appropriate additional mitogenic stimulation, cells in this layer, and other p27Kip1-negative basal cells, are competent for rapid entry into the cell cycle. Consistent with the fact that cancer cells are capable of cell division, all cases of high-grade prostatic intraepithelial neoplasia and invasive carcinoma also showed down-regulation of p27Kip1 as compared with the surrounding normal-appearing secretory cells. In pelvic lymph node metastases, p27Kip1 expression was also reduced. In summary, our results suggest that lack of nuclear p27Kip1 protein may delineate a potential transiently proliferating subcompartment within the basal cell compartment of the human prostate. In addition, these studies support the hypothesis that reduced expression of p27Kip1 removes a block to the cell cycle in human prostate epithelial cells and that dysregulation of p27Kip1 protein levels may be a critical early event in the development of prostatic neoplasia.  相似文献   
9.
Sarcomas can be divided into those with specific translocations displaying monotonous cytomorphology, and those with complex karyotypes and marked cellular pleomorphism. Telomeres contain terminal DNA sequence repeats that maintain chromosomal stability. Telomeres shorten with cell division and may become dysfunctional leading to chromosomal instability. Using a fluorescence in situ hybridization/immunofluorescence method to assess telomere lengths in archival tissues we analyzed these two types of sarcomas using paraffin-embedded primary tumor specimens. Tissues from nine sarcomas with characteristic translocations (two synovial sarcomas, two alveolar rhabdomyosarcomas, two desmoplastic round cell tumors, and one each of infantile fibrosarcoma, myxoid liposarcoma, cellular congenital mesoblastic nephroma) and nine without (four malignant fibrous histiocytomas, two leiomyosarcomas, one pleomorphic rhabdomyosarcoma, one dedifferentiated chondrosarcoma, and one malignant peripheral nerve sheath tumor) were analyzed. In all (nine of nine) cases with specific translocations, which generally have few karyotypic abnormalities, telomere lengths were similar to or reduced compared to surrounding nonneoplastic tissues. In contrast, telomeres in cases lacking specific translocations, which generally contain complex karyotypes, were often found to be dramatically lengthened and heterogeneous. In addition to markedly elongated telomeres, seven of nine (78%) complex cases exhibited large brightly stained regions corresponding to a specific type of promyelocytic leukemia nuclear body found in immortalized cells that maintain telomeres in a telomerase-independent manner [alternative lengthening of telomeres (ALT) pathway]. This phenotype is unlike that of epithelial neoplasms that typically display complex karyotypes with abnormally short telomeres maintained by the enzyme telomerase. The discovery of heterogeneous telomere lengths and evidence of the ALT pathway in the majority of sarcomas with complex karyotypes supports the existence of a telomere maintenance pathway incapable of full karyotypic stabilization in pleomorphic sarcomas. These findings provide additional molecular-genetic evidence supporting the dichotomous grouping of sarcomas into those with characteristic signature translocations without extensive additional karyotypic abnormalities, and those without such signature translocations that typically display very complex karyotypes, and point to telomere dysfunction as a plausible contributor to the chromosomal aberrations found in complex sarcomas.  相似文献   
10.
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