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1.
E M Raney  J T Bennett 《Spine》1992,17(12):1522-1524
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2.
W R Vogler  M R Raney 《Cancer》1988,61(12):2481-2486
Bone marrow and peripheral blood findings at the time of complete remission were analyzed in 333 patients with acute myelogenous leukemia to determine if any variables were predictive for remission duration and survival. Patients were categorized as to percentage of blasts, promyelocytes, erythroid precursors and lymphocytes in the marrow and hemoglobin concentration, leukocyte and platelet counts, and percentage of granulocytes and blasts in the blood. Additionally, the degree of cellularity in the marrow aspirate and biopsy were analyzed. Patients with less than 1% blasts in the marrow had significantly longer remission durations than those with blasts greater than or equal to 1% (P less than 0.01). Those with hypercellular marrows had significantly shorter remission (P less than 0.05) and survival (P less than 0.01). The transient presence of more than 3% blasts in the blood also was suggestive of a shorter remission duration and survival. The presence of less than 1% blasts in the marrow, normal or decreased biopsy cellularity, and no anemia at the time of remission defined a "good" prognostic group. The quality of remission should be assessed in evaluating the results of therapy and assigning further treatment.  相似文献   
3.
We assessed the in vitro activities of daptomycin, linezolid, and quinupristin-dalfopristin (QD) against a contemporary challenge panel of 88 staphylococcal and 90 enterococcal isolates. The staphylococci selected included vancomycin-intermediate Staphylococcus aureus (VISA), methicillin-resistant S. aureus, and coagulasenegative staphylococci. Enterococcal isolates included vancomycin-resistant Enterococcus faecium (VREF) containing either vanA, vanB1, or vanD. The MICs of daptomycin, linezolid, and QD were determined using commercial broth microdilution panels. All three VISA isolates were susceptible to daptomycin, linezolid, and QD. QD was the most active agent against staphylococcal isolates (MIC50 < or = 0.5 microg/ml and MIC90 = 1 microg/ml), including those with decreased susceptibility to vancomycin. QD was also the most active agent against VREF (MIC90 < or = 0.5 microg/ml). No differences were seen for susceptibility of vanA, vanB1, and vanD VREF strains for daptomycin, linezolid, or QD. Daptomycin was the most effective against E. faecalis. On the basis of manufacturer-suggested interpretive criteria, 92% of isolates were susceptible (MIC90 = 4 microg/ml). All isolates tested were susceptible to at least one antimicrobial agent for which interpretive criteria have been defined. Population analysis of three S. aureus isolates for which the daptomycin MICs were 8 microg/ml showed a pattern of homogeneous resistance.  相似文献   
4.
Twenty-nine children (24, male; 5, female) with non-disseminated rhabdomyosarcomas of the bladder or prostate were treated (1978-1980) by a primary chemotherapy regimen consisting of vincristine, actinomycin D, and cyclophosphamide ("Pulse" VAC), with or without local radiotherapy. During the initial 20 wk of chemotherapy, nine children achieved a Clinical Complete Response (CCR). Three of these are without evidence of disease (NED) and have functional bladders, two following partial cystectomy. Four who achieved a CCR subsequently relapsed or remained biopsy positive, but are at present NED following radiotherapy and anterior exenteration. Two patients who achieved CCR status relapsed and have died of disease. Twelve patients had a Clinical Partial Response (CPR) in less than 20 wk and two others in less than 40 wk. Seven of these are NED with intact bladders following chemotherapy-radiotherapy; and an additional patient is NED following partial cystectomy. Four patients in the CPR group have been treated by exenteration following failure to achieve complete response, and are NED. One patient has died, and one has progressive disease. Six patients had an inadequate response to chemotherapy (NR). Anterior exenteration was carried out in three, and two of these have survived. The overall results in these 29 patients are: (A) alive and disease-free with functional bladders, 11; (B) alive and disease-free following anterior exenteration, 10; and (C) dead or death from tumor anticipated, 8. The function of retained bladders (11) has been satisfactory.  相似文献   
5.
BACKGROUND AND AIM OF THE STUDY: Systolic anterior motion (SAM) of the mitral valve resulting in left ventricular outflow obstruction is a well-recognized complication of repair of the degenerative myxomatous mitral valve. A precise mechanism is unknown. A current approach consists of sliding annuloplasty of the posterior leaflet. It was postulated that excess tissue of the anterior mitral leaflet (AML) was as equally (or more) important as the excess posterior mitral leaflet (PML) tissue in the development of SAM subsequent to valve repair. METHODS: Thirty-two patients without post-repair SAM (No-SAM group) were compared with eight patients with SAM (SAM group). The AML and PML heights and the mitral annulus diameter were measured by TEE using mid-esophageal four-chamber and long-axis planes. RESULTS: Pre-repair TEE showed the AML height to be greater in the SAM group (p = 0.04), and that of the posterior leaflet tended to be greater (p = 0.08), whilst the annular dimensions were similar in both groups. In the post-repair status, the AML height was markedly greater (p = 0.005) and the annulus markedly smaller (p = 0.001) in the SAM group. Post-repair assessment showed the relative difference between AML height and annular dimension (AML - Ann) as well as the difference between combined leaflet heights and annular dimension (AML + PML - Ann) to be strikingly greater in the SAM group as compared with the No-SAM group (p = 0.001). CONCLUSION: A disparity between dimension of the annulus following mitral valve repair and combined heights of the two leaflets explains post-repair SAM. The AML height is a more important factor in the development of SAM. Thus, surgical techniques to reduce AML heights should be considered in patients with disproportionately large anterior leaflets in order to prevent SAM. Selection of size of the annuloplasty ring should take into consideration the height of the AML.  相似文献   
6.
Extended-spectrum beta-lactamases (ESBLs) are enzymes found in gram-negative bacilli that mediate resistance to extended-spectrum cephalosporins and aztreonam. In 1999, the National Committee for Clinical Laboratory Standards (NCCLS) published methods for screening and confirming the presence of ESBLs in Klebsiella pneumoniae, Klebsiella oxytoca, and Escherichia coli. To evaluate the confirmation protocol, we tested 139 isolates of K. pneumoniae that were sent to Project ICARE (Intensive Care Antimicrobial Resistance Epidemiology) from 19 hospitals in 11 U.S. states. Each isolate met the NCCLS screening criteria for potential ESBL producers (ceftazidime [CAZ] or cefotaxime [CTX] MICs were > or =2 microg/ml for all isolates). Initially, 117 (84%) isolates demonstrated a clavulanic acid (CA) effect by disk diffusion (i.e., an increase in CAZ or CTX zone diameters of > or =5 mm in the presence of CA), and 114 (82%) demonstrated a CA effect by broth microdilution (reduction of CAZ or CTX MICs by > or =3 dilutions). For five isolates, a CA effect could not be determined initially by broth microdilution because of off-scale CAZ results. However, a CA effect was observed in two of these isolates by testing cefepime and cefepime plus CA. The cefoxitin MICs for 23 isolates that failed to show a CA effect by broth microdilution were > or =32 microg/ml, suggesting either the presence of an AmpC-type beta-lactamase or porin changes that could mask a CA effect. By isoelectric focusing (IEF), 7 of the 23 isolates contained a beta-lactamase with a pI of > or =8.3 suggestive of an AmpC-type beta-lactamase; 6 of the 7 isolates were shown by PCR to contain both ampC-type and bla(OXA) genes. The IEF profiles of the remaining 16 isolates showed a variety of beta-lactamase bands, all of which had pIs of < or =7.5. All 16 isolates were negative by PCR with multiple primer sets for ampC-type, bla(OXA), and bla(CTX-M) genes. In summary, 83.5% of the K. pneumoniae isolates that were identified initially as presumptive ESBL producers were positive for a CA effect, while 5.0% contained beta-lactamases that likely masked the CA effect. The remaining 11.5% of the isolates studied contained beta-lactamases that did not demonstrate a CA effect. An algorithm based on phenotypic analyses is suggested for evaluation of such isolates.  相似文献   
7.
Developmental dyslexia affects 40–60% of children with a familial risk (FHD+) compared to a general prevalence of 5–10%. Despite the increased risk, about half of FHD+ children develop typical reading abilities (FHD+Typical). Yet the underlying neural characteristics of favorable reading outcomes in at‐risk children remain unknown. Utilizing a retrospective, longitudinal approach, this study examined whether putative protective neural mechanisms can be observed in FHD+Typical at the prereading stage. Functional and structural brain characteristics were examined in 47 FHD+ prereaders who subsequently developed typical (n = 35) or impaired (n = 12) reading abilities and 34 controls (FHD?Typical). Searchlight‐based multivariate pattern analyses identified distinct activation patterns during phonological processing between FHD+Typical and FHD?Typical in right inferior frontal gyrus (RIFG) and left temporo‐parietal cortex (LTPC) regions. Follow‐up analyses on group‐specific classification patterns demonstrated LTPC hypoactivation in FHD+Typical compared to FHD?Typical, suggesting this neural characteristic as an FHD+ phenotype. In contrast, RIFG showed hyperactivation in FHD+Typical than FHD?Typical, and its activation pattern was positively correlated with subsequent reading abilities in FHD+ but not controls (FHD?Typical). RIFG hyperactivation in FHD+Typical was further associated with increased interhemispheric functional and structural connectivity. These results suggest that some protective neural mechanisms are already established in FHD+Typical prereaders supporting their typical reading development.  相似文献   
8.
This report describes the results of bone marrow leukocyte immunophenotypic studies, DNA index measurement, and chromosome analysis in a newborn with Down syndrome and transient myeloproliferative disorder. The infant's initial leukocytosis with immature cells in the peripheral blood and thrombocytopenia resolved without treatment by 6 months of age, and he was well at 2 years of age. The lack of specific reactivity between the patient's morphologically immature cells and multiple monoclonal antibodies directed against lymphoid and myeloid leukemia cells may be characteristic of this disorder. Other cases should be examined for immunophenotype to correlate the results with chromosomal analysis and to provide a basis for comparison in those who subsequently develop true acute leukemia.  相似文献   
9.
The pathologic materials and clinical courses of 36 children aged 1 month-22 years, with histiocytosis × (H-X) seen at the Philadelphia Children's Cancer Research Center from 1970 to 1979 were reviewed. The pathologic subtype of H-X was favorable (type II) in 31 patients, unfavorable (type I) in one patient, and unclassified in four patients whose specimens were limited to a skin biopsy. Sixteen patients had localized H-X involving bone (14 patients), soft tissue (1 patient), or skin only (1 patient); all are alive and well after treatment with surgery alone (12 patients), radiation therapy (RT) (3 patients), or observation (1 patient); only 1 of the 16 developed recurrent H-X. The other 20 patients presented with multifocal H-X involving the skeleton alone (3 patients); the skeleton and soft tissues other than liver (7 patients); soft tissue exclusive of the liver (3 patients); soft tissue including the liver (4 patients); or soft tissues, skeleton, and liver or multiple drugs ± RT (15 patients). Seven of the 20 patients are alive and well without recurrence at a median of 4 years after diagnosis. Nine of the 20 patients, including 3 with liver dysfunction, responded completely to initial therapy but developed recurrence; each was retreated with drugs and is alive and well at a median of 4 years. The remaining 4 patients had widespread disease with dysfunction of the liver and/or hematopoietic system at diagnosis, failed to respond, and died. We conclude that (1) patients with multiple bony lesions with or without associated soft tissue disease or skin involvement have a favorable outlook and do not require systemic chemotherapy; (2) systemic treatment also is unnecessary for patients with localized H-X since recurrence is rare; (3) drugs can benefit patients with multifocal H-X, although the optimal duration of therapy is unclear; and (4) favorable response to treatment indicates high probability of disease-free survival. However, organ dysfunction at diagnosis is ominous: four of seven patients with liver dysfunction are dead, as are all three patients who prsented with peripheral blood count depression.  相似文献   
10.
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