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41.
BACKGROUND: Polymorphonuclear elastase is an early and sensitive indicator of neonatal infection when performed at the beginning of clinical symptoms. PATIENTS AND METHODS: To investigate the diagnostic value of elastase measurement in cord blood immediately after birth, 211 neonates (103 boys vs 108 girls, 154 vaginal delivery vs 57 cesarean section). Mean gestational age 38.9 weeks (range: 30-42), mean birth weight 3,260 g (range: 1,430-4,920 g). After clinical, bacterial and biological screening, the infants were classified in three groups. Group A (n = 118): none infectious risk factor neither clinical signs of infection; group B (n = 79): one or more risk factors but no evidence of infection; group C (n = 14): proved or probable infection. Polymorphonuclear elastase was measured in cord blood of all infants using an heterogeneous enzyme-linked-immunosorbent assay. RESULTS: We observed higher elastase values in group C (176 +/- 67 micrograms/L) than in group A (91 +/- 64 micrograms/L) and B (67 +/- 61 micrograms/L) (mean +/- SD, P = 0.0001). With a cutoff value fixed at 80 micrograms/L, the sensitivity of this test applicated to neonates presenting materno-fetal infectious risk factor(s) was 85% (12/14), specificity 74% (59/79), positive predictive value 37%, and negative predictive value 96%. CONCLUSION: Because two of the 14 infected infants (15%) were not detected by elastase dosage in cord blood, this test cannot be used as an early indicator of materno-fetal infection.  相似文献   
42.
The purpose of this study was to determine the outcome of patients with metastatic breast cancer treated with high-dose busulfan (Bu), melphalan (Mel) and thiotepa (TT) followed by peripheral blood stem cell (PBSC) infusion. Fifty-one patients with chemotherapy refractory (n = 32) or responsive (n = 19) metastatic breast cancer received Bu (12 mg/kg), Mel (100 mg/m2) and TT (500 mg/m2) followed by PBSC collected after chemotherapy and growth factor (n = 43) or growth factor alone (n = 8). The 100 day treatment-related mortality was 8% including one death from cytomegalovirus pneumonia, one from aspiration pneumonia and two from regimen-related toxicity (RRT). Seven of 28 refractory (25%) and 5/7 (71%) responsive patients with evaluable disease achieved a complete response of all measurable disease or all soft tissue disease with at least improvement in bone lesions (PR*). Fifteen of 51 patients (29%) are alive and progression-free a median of 423 days (range 353-934) after treatment, 5/32 (16%) with refractory disease and 10/19 (53%) with responsive disease. The probabilities of progression-free survival (PFS) at 1.5 years for the patients with refractory (n = 32) and responsive (n = 19) disease were 0.24 and 0.53, respectively. These preliminary data suggest that high-dose Bu/Mel/TT has significant activity in patients with advanced breast cancer and may be superior to some previously published regimens.  相似文献   
43.
CDC 25 is a dual phosphatase responsible for dephosphorylation and, thus, activation of CDC 2 kinase in G2. Abnormal activation of cyclin B-associated CDC 2 kinase has been implicated in apoptosis induced by cancer chemotherapeutic agents such as paclitaxel (Taxol) and etoposide (VP-16). In this study, we found that the CDC 2 kinase could be transiently activated when nasopharyngeal carcinoma NPC-TW01 cells were treated for 3 h with a new anticancer agent, GL331. GL331 treatment also induced a concomitant increase in CDC 25A phosphatase activity and a reduced level of Tyr-15-phosphorylated CDC 2 in NPC-TW01 cells. Furthermore, subsequent apoptotic DNA fragmentation induced by GL331 could be interrupted by treatment of the cells with the cyclin B1-specific antisense oligonucleotides, suggesting that abnormal activation of cyclin B1-associated CDC 2 kinase and CDC 25A phosphatase was involved in GL331-induced apoptosis. Raf-1 has been shown to associate with CDC 25A and, thus, to stimulate its phosphatase activity. Our results revealed that GL331 could facilitate the association of CDC 25A with Raf-1, resulting in the cascade of CDC 25A phosphatase activation and CDC 2 kinase activation, as well as related signaling pathways, and ultimately causing apoptosis in cancer cells.  相似文献   
44.
OBJECTIVE: Endoscopic injection sclerotherapy and variceal ligation are two popular endoscopic methods used to treat esophageal variceal hemorrhage. These two methods have not been compared with regard to esophageal dysfunction after treatment. This is a prospective investigation of esophageal dysmotility after endoscopic injection sclerotherapy and variceal ligation. METHODS: Sequential changes of esophageal motility after endoscopic injection sclerotherapy (n = 25) and variceal ligation (n = 25) were investigated in 50 cirrhotic patients with recent variceal bleeding. Another 22 cirrhotics without esophageal varices were included as controls. Radionuclide esophageal transit tests were performed before initial endoscopic treatment, and 1 and 3 months after variceal eradication. RESULTS: The baseline esophageal transit time was longer in both the sclerotherapy (n = 25, 7.8 +/- 1.4 s) and ligation groups (n = 25, 8.2 +/- 1.8 s) than in controls (n = 22, 6.7 +/- 0.7 s, p < 0.005). The transit time was longer in patients with large varices than in those with small varices (8.3 +/- 1.7 vs. 7.2 +/- 0.7 s, p < 0.05). In the sclerotherapy group, the transit time was prolonged 1 month after variceal eradication, compared with its pretreatment state (n = 20, 7.6 +/- 1.5 vs. 10.0 +/- 2.2 s, p < 0.0001) but was shortened at 3 months compared with 1 month after variceal eradication (n = 12, 10.7 +/- 1.5 vs. 8.6 +/- 2.2 s, p < 0.05). Multiple regression analysis showed that the number of treatment sessions required to eradicate varices was the only significant factor associated with prolonged transit time (p < 0.05). In the ligation group, the transit time changed little at 1 month or 3 months after variceal eradication. CONCLUSIONS: Impairment of esophageal motility can be significant with endoscopic injection sclerotherapy but is reversible. However, endoscopic variceal ligation exerts no significant impact on esophageal motility.  相似文献   
45.
We describe in this report a sensitive and direct method for the analysis of tamoxifen (TAM) in microsamples of plasma. The drug and internal standard (quinine bisulfate, I.S.) were separated on a 10-microm particle, 10 cm X 8 mm CN cartridge in conjunction with a radial compression system. The mobile phase was a mixture of 0.1 M sodium acetate in 0.001 M tetrabutylammonium phosphate solution (pH 6) and methanol (30:70, v/v) at a flow-rate of 4 ml/min. After addition of I.S. and o-phosphoric acid in acetonitrile (0.6 M) to the plasma (30 microl), the mixture was placed in an ultraviolet shortwave transluminator for 2 min prior to injection into the chromatograph. The compounds were detected in the effluent fluorometrically at excitation and emission wavelengths of 258 and 378 nm, respectively. Under these conditions, no interference in the assay from any endogenous substance or other concurrently used drugs was observed and the retention times of I.S. and TAM were 4.4 and 10.15 min, respectively. The concentration of TAM in plasma was linearly (r>0.9983) related to the peak height ratio (TAM/I.S.) in the range 0.01-2.0 microg ml(-1) and C.V. at 0.075, 0.4 and 1.2 microg ml(-1) was < or = 4.96%. We are currently using this assay for monitoring TAM in plasma and investigating its pharmacokinetics in cancer patients receiving cytotoxic drugs in addition to TAM as a multi-drug resistance modifier.  相似文献   
46.
The current environment in which medicine is taught and practiced requires that medical schools pay increased attention to the faculty member's roles, rewards, career development, and productivity. Medical schools must make strategic decisions about the allocation of resources that can nurture their faculties and support the activities in academic and community settings in which faculty are involved. From 1993 to 1995 Allegheny University of the Health Sciences (formerly Medical College of Pennsylvania and Hahnemann University) designed a comprehensive system for the professional development of faculty. This system is based upon expanded categories of faculty academic activity and scholarship. New programs were implemented to reorient faculty toward conducting and documenting the expanded array of scholarly activities. The main characteristics of the new system are the establishment of formally defined performance expectations, the vertical alignment of the individual faculty member's objectives with the department's mission and the school's mission, and an increasing emphasis upon faculty interdependence, accountability, and use of sound business practices. The authors describe these and other aspects of the design of the new system in detail and report initial results and lessons learned from the system's implementation, evaluation, and dissemination throughout the university. The long-term success of this comprehensive professional development program will be assessed over time by observing how this institution advances its mission in a well-planned and cost-effective manner that retains talented, productive, and professionally fulfilled faculty.  相似文献   
47.
PURPOSE: We report a case of postoperative reparalysis in the recovery room, following nebulized epinephrine. The patient was pharmacologically reversed with edrophonium after paralysis with rocuronium. CLINICAL FINDINGS: A 12-yr-old girl developed postoperative reparalysis following the intraoperative administration of rocuronium. A total of 0.92 mg.kg-1 rocuronium was administered. After surgery, pharmacological reversal was achieved with 20 mg edrophonium with 0.15 mg atropine sulfate iv 35 min after the last administration of rocuronium. Muscular relaxation was monitored using an ulnar peripheral nerve stimulator (PNS). After reversal, a full train-of-four and sustained tetanus at 50 Hz were present. In the recovery room, following nebulized epinephrine, the patient became apneic. The patient was paralyzed and an ulnar PNS demonstrated only one faint twitch. The paralysis was reversed with 1.5 mg neostigmine with 0.3 mg glycopyrrolate. CONCLUSION: Postoperative reparalysis following rocuronium may be a cause of postoperative respiratory distress. The definitive diagnosis is made using PNS and observing the response to pharmacological reversal. Nebulized epinephrine may have a previously undescribed role in the development of postoperative reparalysis.  相似文献   
48.
We describe two sibs with chorioretinal dystrophy, hypogonadotrophic hypogonadism, and cerebellar ataxia, Boucher-Neuh?user syndrome, a rare but distinct pleiotropic single gene disorder with an autosomal recessive pattern of inheritance. The cases presented illustrate that this syndrome is still poorly recognised. We provide a review and analysis of previously reported cases and the differential diagnosis, which might aid in the identification of additional cases.  相似文献   
49.
50.
The loss of immunotolerance has been implicated in the pathogenesis of both primary biliary cirrhosis (PBC) and idiopathic, immune-mediated thrombocytopenic purpura (ITP). An association between these two autoimmune diseases has been well described. We describe a 41-year-old woman in whom ITP developed 457 days after liver transplantation for PBC while receiving immunosuppressive medications sufficient to maintain allograft function. Our case report, the first to describe post-transplant ITP in association with PBC, demonstrates the persistence of the underlying immune dysregulation of PBC after transplantation. The practice of decreasing the dosage of immunosuppressive medication to maintenance levels after transplantation may unmask the effects of this defect in immunotolerance.  相似文献   
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