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81.
Preoperative staging with computerized axial tomography and biochemical laboratory tests in patients with hepatic metastases. 总被引:3,自引:0,他引:3 下载免费PDF全文
Preoperative biochemical liver function tests and computerized axial tomographic (CAT) scans were performed on 100 patients as part of a prospective randomized study of treatments for liver metastases from colorectal cancer. The CAT scans reliably reflected the presence of disease in most patients but only accurately demonstrated the number and location of metastases in 43% of the patients. Extrahepatic metastases were present in 35 patients but were only seen on the CAT scans in three of these patients. The biochemical tests, which were useful for detecting hepatic metastases, were alkaline phosphatase (AP), lactic dehydrogenase (LDH), and carcinoembryonic antigen (CEA). When hepatic disease was minimal, these tests were less likely to be elevated than when there was extensive disease. Even with the combination of late generation CAT scans and biochemical tests, the accurate quantification and location of hepatic metastases and extrahepatic disease require a surgical assessment. 相似文献
82.
G. M. Kotzar D. T. Davy J. Berilla V. M. Goldberg 《Journal of orthopaedic research》1995,13(6):945-955
Torques generated in one subject during the early postoperative period were measured with a telemeterized total hip component. The patient was examined during gait, stair ascent, rising from a chair, and single-limb stance. The torques were plotted against both the resultant joint contact force and the force component directed along the stem axis. During gait, the maximum torque was 35 Nm, recorded at a walking velocity of 1.7 m/sec. The peak torques during stair ascent and during rising from a seated position were found to be 23 and 15 Nm, respectively. The maximum value for torque measured in this study was 37 Nm during one attempt at single-limb stance. Comparison of plots for torque versus stem-axis component for the four activities shows that the torque increased more rapidly for chair exits than for gait up to resultant contact force values of as much as 1,000 N. For stair ascent, the same was true to values of 1,400 N. Within any given activity, the relationship between stem torque and resultant or stem-axis force showed considerable variability. These results indicate that experiments evaluating the stability of femoral components in total hip arthroplasty should incorporate a component directed along the stem axis, as well as a component normal to the plane of the prosthesis. The results also suggest that theoretical stress analysis models should consider the broad variability in the orientation of the joint force at the hip. 相似文献
83.
MY Mancao LJ Sindel PH Richardson FM Silver 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(1):118-120
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup. 相似文献
84.
Azra Raza Harvey D. Preisler Ya Qin Li Richard A. Larson Jack Goldberg George Browman John Bennett Hans Grunwald Ralph Vogler Cathi Kukla 《American journal of hematology》1993,42(4):359-366
A pilot study was conducted of the biological characteristics of the leukemia cells of newly diagnosed patients with poor prognosis acute myelogenous leukemia (AML). This study included measurements of the pretherapy proliferative rate of the leukemia cells in vivo, assessment of differentiation in vivo during remission induction therapy, and the level of expression of the fms, myc, and IL1β genes in pretherapy leukemia cells. Short cell cycle times were characteristic of the best prognostic category and were associated with a rapid reduction in marrow leukemia cells in cytosine arabinoside (araC)-sensitive patients. Expression of c-fms was associated with rapid reduction in marrow leukemia cells during araC therapy and with a successful treatment outcome. Expression of the IL1β gene was associated with short remissions. These studies suggest that when compared to newly diagnosed standard prognosis AML, the leukemia of poor prognosis patients is more likely to exhibit long cell cycle times, low levels of fms expression, and is less likely to be associated with myeloid differentiation during remission induction therapy. © 1993 Wiley-Liss, Inc. 相似文献
85.
Performance of schizophrenic patients on putative neuropsychological tests of frontal lobe function 总被引:4,自引:0,他引:4
T E Goldberg J R Kelsoe D R Weinberger N H Pliskin P D Kirwin K F Berman 《The International journal of neuroscience》1988,42(1-2):51-58
Though individual tests thought to assess frontal lobe function have been administered to patients with schizophrenia for many years, approaches in which a number of tests thought to tap a single function or brain region have rarely been used. Such an approach might define a critical test or a common dysfunctional cognitive process. In the present study four putative neuropsychological tests of frontal lobe integrity, namely, the Wisconsin Card Sorting Test, the Category Test, Trail Making B, and verbal fluency, were administered to 28 patients with schizophrenia. Seventy-five percent performed abnormally on at least one test. However, relationships among the test results were difficult to characterize, either by correlation or factor analysis. A hierarchical arrangement in which "higher order" tests proscribe performance on "lower order" tests did not appear to be present. Regarding sensitivity, Trails B, the only timed test, was most frequently impaired and verbal fluency was least frequently impaired. The results suggest that the tests assess somewhat different aspects of frontal lobe function, and that no single frontal lobe test is uniquely sensitive to cognitive impairment in schizophrenia. 相似文献
86.
Summary The incidence of strains producing transferable -lactamases capable of hydrolyzing third generation cephalosporins or aminothiazole-oximino substituted monobactams in five Buenos Aires hospitals during a four month period was studied. These enzymes were categorized by 1) MIC 1 mg/l for third generation cephalosporins; 2) MIC < 0.06 mg/l for third generation cephalosporins combined with clavulanic acid or sulbactam; 3) sensitivity to imipenem or cephamycins (excluding permeability mutants); and 4) transferable resistance by conjugation. -lactamases hydrolyzing aminothiazole-oximino substituted monobactams were produced by 17.2% of Enterobacteriaceae from intensive care unit patients; 3.6% from inpatients of other units and 1.2% from outpatients. Producers were mainlyKlebsiella spp. (45/46) resistant to aminoglycosides (most of them AAC 3 — AAC 6 producers). Three strains had a an isoelectric point of 6.0, two of 6.5 and three of 7.7. TEM-1 -lactamase (isoelectric point 5.4) was detected in 6/8 strains. An inocolum effect was observed in 40/46 strains. AKlebsiella pneumoniae strain preserved since 1982 also produced a transferable -lactamase hydrolyzing aminothiazole-oximino substituted monobactams.
Vorkommen von Bakterienstämmen mit erweitertem Breitspektrum -Laktamasen in Argentinien
Zusammenfassung Während einer Zeit von vier Monaten wurde an fünf Krankenhäusern in Buenos Aires nach dem Vorkommen von Stämmen mit Bildung übertragbarer -Laktamasen gesucht, die Cephalosporine der dritten Generation oder aminothiazol-oximino-substituierte Monobaktame hydrolysieren. Kriterien für die Selektion dieser Enzyme waren 1) MHK-Werte von 1 mg/l für Cephalosporine der dritten Generation; 2) MHK-Werte von < 0,06 mg/l für Drittgenerationscephalosporine in Kombination mit Clavulansäure oder Sulbactam; 3) Empfindlichkeit gegenüber Imipenem oder Cephamycinen; 4) Resistenz übertragbar. Zur Bildung von -Laktamasen mit hydrolytischer Aktivität gegen Aminothiazol-oximinosubstituierte Monobaktame waren 17,2% der Enterobacteriaceae-Isolate von Intensivpflegepatienten befähigt, 3,6% der Isolate von Patienten von anderen Stationen und 1,2% der Isolate von ambulanten Patienten. Die meisten der Stämme, die diese Enzyme bildeten (45/46), waren aminoglykosidresistenteKlebsiella spp. (Synthese von AAC 3-AAC 6). Der isoelektrische Punkt lag bei drei Enzymen bei 6,0, in zwei Fällen bei 6,5 und in drei Fällen bei 7,7. Sechs von acht Stämmen bildeten TEM-1 -Laktamase. Bei 40 der 46 Stämme wurde ein Inokulumeffekt festgestellt. Die Bildung übertragbarer -Laktamasen mit hydrolytischer Wirkung gegen Aminothiazolyl-oximino-substitutierte Monobaktame wurde in einem bereits seit 1982 gelagertenKlebsiella pneumoniae-Stamm nachgewiesen.相似文献
87.
A pharmacy-coordinated process is described in which the frequency and types of inappropriate drug prescribing are evaluated as part of the medical staff quality assurance and physician credentialing program. A pharmacist intervention program was implemented at an 838-bed private hospital to review all medication orders for appropriateness and to intervene with physicians and nurses when problems in drug prescribing or administration were identified. During a five-year period there were more than 6500 drug therapy interventions. Because of the recurrent problems identified, the medical staff asked the pharmacy department to develop a process for objectively evaluating the quality of prescribing practices that could be used in the medical staff quality assurance program and in physician credentialing. The drug-prescribing activities of physicians applying for clinical privileges are subjected to a "macro" review by using a computerized clinical financial information system to extract drug-use information from patients' bills. In a "micro" review, patient records are retrospectively analyzed by Pharm.D. clinical specialists; all medications prescribed by the physician for those patients being evaluated are scrutinized. Appropriate response scores are calculated by dividing the number of appropriate responses by the total responses. The pharmacy department in this hospital has assumed a more active role in patient care through its participation in a process for objectively evaluating the quality of prescribing practices. 相似文献
88.
Global dendritic calcium spikes in mouse layer 5 low threshold spiking interneurones: implications for control of pyramidal cell bursting 总被引:1,自引:1,他引:1
Interneuronal networks in neocortex underlie feedforward and feedback inhibition and control the temporal organization of pyramidal cell activity. We previously found that lower layer neocortical interneurones can reach action potential threshold in response to the stimulation of a single presynaptic cell. To better understand this phenomenon and the circuit roles of lower layer neocortical interneurones, we combined two-photon calcium imaging with whole cell recordings and anatomical reconstructions of low threshold spiking (LTS) interneurones from mouse neocortex. In both visual and somatosensory cortex, LTS interneurones are somatostatin-positive, concentrated in layer 5 and possess dense axonal innervation to layer 1. Due to the LTS properties, these neurones operate in burst and tonic modes. In burst mode, dendritic T-type calcium channels boosted small synaptic inputs and triggered low threshold calcium spikes, while in tonic mode, sodium-based APs evoked smaller calcium influxes. In both modes, the entire dendritic tree of LTS interneurones behaved as a 'global' single spiking unit. This, together with the fact that synaptic inputs to layer 5 LTS cells are facilitating, and that their axons target the dendritic region of the pyramidal neurones where bursts are generated, make these neurones ideally suited to detect and control burst generation of individual lower layer pyramidal neurones. 相似文献
89.
The data for 197 mother-infant pairs from two longitudinal studies were analyzed to assess relations between maternal attachment representations; atypical maternal behavior, coded with a new tool. Atypical Maternal Behavior Instrument for Assessment and Classification (AMBIANCE), and infant attachment. Both maternal and infant attachment were systematically related to atypical maternal behavior: mothers who were Unresolved on the Adult Attachment Interview and those whose infants were disorganized in the Strange Situation Procedure engaged in more atypical behaviors than those who were not Unresolved and whose infants showed organized patterns of attachment, respectively. Regression analyses indicated that when tested as a mediator, atypical maternal behavior as measured on the AMBIANCE did not reduce the association between maternal Unresolved status and infant disorganized attachment. This may, in part, reflect the fact that our low-risk sample did not include enough cases in the risk categories. These data provide preliminary empirical validation for the AMBIANCE and strengthen the evidence for links between atypical maternal behavior and disorganized attachment but indicate that in addition to maternal attachment representations, other factors must contribute to atypical maternal behavior. 相似文献
90.
Implications of the World Health Organization study of mental illness in general health care for training primary care staff. 总被引:1,自引:1,他引:1 下载免费PDF全文
A substantial international study of mental disorders seen in primary care settings has shown that there are marked differences in prevalence between centres. Detection of mental disorders is better in centres using a 'personal' style of clinical service, and where there has been close collaboration between psychiatrists and general practitioners. However, even in the better centres, substantial numbers of mental disorders are missed and treatment often appears to be given regardless of diagnosis. It is argued that changes need to be made to the way in which both undergraduates and vocational trainees are taught about mental disorders, so that teaching emphasizes the psychological syndromes that general practitioners are likely to meet in their everyday work. Training packages need to be developed for primary care staff in the detection and management of mental disorders. 相似文献