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61.
Cressey TR Jourdain G Lallemant MJ Kunkeaw S Jackson JB Musoke P Capparelli E Mirochnick M 《Journal of acquired immune deficiency syndromes (1999)》2005,38(3):283-288
OBJECTIVE: To determine nevirapine (NVP) plasma levels during the postpartum period after a single intrapartum NVP dose for the prevention of mother-to-child transmission. METHODS: Plasma samples at delivery and during days 8 to 45 postpartum were obtained from HIV-infected Thai women who received an intrapartum NVP dose in the Perinatal HIV Prevention Clinical Trial-2 (PHPT-2) for the prevention of perinatal HIV transmission. These data were combined with NVP concentration data from 2 phase 1 studies of NVP for a population analysis. RESULTS: The median NVP level fell to 68 ng/mL (range: <50-228, n = 43) 8 to 14 days after dosing and to 51 ng/mL (range: <50-166, n = 25) between 15 and 21 days. During the second and third weeks postpartum, NVP levels were below the limit of quantitation in 23% and 44% of samples, respectively. Between 21 and 45 days, no sample had a quantifiable NVP concentration. A simulation derived from the population analysis predicts that NVP concentration falls to less than 10 ng/mL in 5% of women by 11 days, in 50% of women by 17.5 days, and in 95% of women by 28 days. CONCLUSIONS: Significant NVP concentrations remained for up to 20 days in these Thai women. To ensure that coverage is maintained until NVP concentrations fall to nonsuppressive levels, 1 month of additional antiretroviral treatment after delivery should be considered to prevent the emergence of resistant viruses. 相似文献
62.
Dr. Martin Scholz Stefanie Märzheuser-Brands Joachim Gottschalk Johannes C. Böck Wolfgang R. Lanksch 《Neurosurgical review》1994,17(1):89-93
The authors add to the literature a case report of a 32-year-old man with an intramedullary epidermoid cyst at the level of D 3/4, that was successfully operated on. There are several previous reports in the literature, but only five of these include MRI studies. 相似文献
63.
64.
Traumatic brain and spinal cord injuries are severe burdens for the patients, their relatives, the health care providers and society as a whole. Recent data demonstrate the magnitude of the problem: It is mostly a disease of the young gen-eration (age 20-45 years) with mortality rates for severe traumatic brain injury (TBI) between 40-50%. In approximately 60% of cases, multiple trauma is accompanied by head injury. The outcome of TBI is determined not only by the extent and severity of the primary insult, but also by the degree of secondary brain damage. In the subgroup of severe TBI (GCS=8) only 25%t of patients showed a complete recovery or had minor neurological deficits; 15% resulted in a lifelong disability or even in a permanent vegetative state. Economically, the impact of TBI is enormous - estimates of the costs of TBI in the U.S. range from 4-15 billion dollars per year. Valid data for Germany are not yet available. 相似文献
65.
66.
Ockert D Schellong S Bergert H Scholz A Zimmermann T Nagel M Saeger HD 《Zentralblatt für Chirurgie》1999,124(1):7-11
In spite of quite a few clinical trials the benefit of venous thrombectomy is seen controversially. The primary objectives of treating venous thrombosis are survival rate, prevention of pulmonary embolism and of postthrombotic syndrome. We report our experience with 47 patients who underwent venous thrombectomy. The mortality rate was 0%. We did not observe clinically relevant pulmonary embolism. After two years 90% of thrombectomised veins were patent. The mortality rates given in the literature of conservative treatment with heparin and following oral anticoagulation are 0.4 to 1.6%. Fibrinolysis shows mortality rates of 1 to 2.4, and thrombectomy of 3.8%, respectively. Venous thrombectomy is an effective treatment to prevent pulmonary embolism. In our own experience we saw no clinically significant pulmonary event. The danger of embolism rises with the proximity of the venous thrombus. Therefore those patients may have the greatest potential benefit from thrombectomy who present with a mobile inguinal thrombus or a thrombus in the iliac vein. So far there are no statistically sufficient data to support the indication of thrombectomy to prevent a postthrombotic syndrome. 相似文献
67.
Raghavan Krishnaswamy S. Gray David B. Scholz Thomas H. Nemeth Gregory A. Hussain Munir A. 《Pharmaceutical research》1996,13(12):1815-1820
Purpose. The objective was to evaluate the degradation profile of the elastase inhibitor DMP 777 and lay the foundation for formulation development.
Methods. The pKa was determined by potentiometric titration in mixed-aqueous solvents. The degradation kinetics were studied as a function of pH, buffer concentration, ionic strength, methanol concentration and temperature using a stability-indicating HPLC assay. The degradation products were identified by LC-MS, NMR, and by comparison with authentic samples.
Results. The pKa for the protonated piperazine nitrogen was estimated to be 7.04. The pH-rate profile is described by specific acid-, water-, and specific base-catalyzed pathways. The pH of maximum stability is in the range of 4 to 4.5 where water is the principal catalyst in the reaction. Buffer catalysis, primary salt effects and medium effects were observed. The proposed mechanism for acid catalyzed degradation is the rarely observed AAL1 which involves alkyl-nitrogen heterolysis. The driving force for the reaction appears to lie in the stability of the benzylic carbocation. The proposed mechanism for base catalyzed degradation is BAC2 which involves -lactam ring opening. The -lactam ring of DMP 777, a monolactam, appears to be as reactive as that in benzylpenicillin in the k
OH controlled region where a similar mechanism of hydrolysis should be operative. A contributing factor to this increased reactivity may lie in the reduced basicity of the -lactam nitrogen making it a good leaving group.
Conclusions. The degradation profile indicates that development of a solution dosage form of DMP 777 with adequate shelf-life stability at room temperature is feasible. 相似文献
68.
Edmund Przegaliński Leokadia Baran Władysław Palider Joanna Siwanowicz 《Psychopharmacology》1979,62(3):295-300
The central action of the potential antidepressant drug pizotifen (Sandomigran) was studied in mice, rats and rabbits. Pizotifen in doses up to 10 mg/kg i.p. was ineffective in classic tests for antidepressant activity. It neither antagonized the effects of reserpine in rats (hypothermia, ptosis) nor potentiated the effects of amphetamine (in mice and rats), nialamide or L-dopa (in mice) on locomotor activity. However, its antidepressant activity was found in the despair test in rats.On the other hand, pizotifen inhibited the head twitch reaction induced by L-5-hydroxytryptophan in mice (ED50=0.009 mg/kg, i.p.) and by 5-methoxytryptamine (+tranylcypromine) in rats (ED50=0.45 mg/kg, i.p.). It also antagonized tryptamine-induced clonic convulsions of fore-paws in rats (ED50=0.35 mg/kg, i.p.), and in doses of 5–10 mg/kg s.c. inhibited hyperthermia produced by LSD in rabbits. Finally, pizotifen (0.1–0.3 mg/kg, i.v.) inhibited or abolished LSD- or quipazine-induced stimulation of the hind limb flexor reflex of spinal rats; the above effect was not due to noradrenolytic action of the drug. These results suggest that pizotifen strongly blocks the central postsynaptic serotonin receptors. 相似文献
69.
Antineoplastic effects of partially HLA-matched irradiated blood mononuclear cells in patients with renal cell carcinoma. 总被引:11,自引:0,他引:11
Roger K Strair Dale Schaar Daniel Medina Mary B Todd Joseph Aisner Robert S DiPaola Jacqueline Manago Beth Knox Amanda Jenkinson Rachelle Senzon Christina Baker Dudek Liesel Marie Ciardella Mercy Kuriyan Arnold Rubin Edmund C Lattime 《Journal of clinical oncology》2003,21(20):3785-3791
PURPOSE: Vaccines, cytokines, and other biologic-based therapies are being developed as antineoplastic agents. Many of these agents are designed to induce an autologous immune response directed against the malignancy. In contrast, hematopoietic stem-cell transplantation is being developed as a form of allogeneic immunotherapy. This study tests the tolerance and antineoplastic activity of sequential infusions of partially HLA-matched allogeneic blood mononuclear cells (obtained from relatives) when administered outside of the context of a hematopoietic stem-cell transplantation. The cells are irradiated to prevent graft-versus-host disease. PATIENTS AND METHODS: Fifteen patients with relapsed or refractory malignancies for which no standard therapy was available were enrolled onto a clinical trial designed to assess the tolerability and antineoplastic effects of irradiated partially HLA-matched blood mononuclear cells obtained from relatives. RESULTS: There was disease regression in three patients with metastatic renal cell carcinoma during treatment. There was disease progression in six patients with metastatic renal cell carcinoma and two patients with metastatic melanoma during treatment. There was no change in disease state in several other patients. CONCLUSION: Irradiated allogeneic blood mononuclear cells administered outside the context of hematopoietic stem-cell transplantation may induce disease responses in patients with relapsed or refractory malignancies. Transfusion of irradiated allogeneic blood mononuclear cells should be developed further as a novel therapeutic antineoplastic approach. 相似文献
70.
In this case report we discuss the anaesthetic management of newborns with esophageal atresia classified as Vogt III b. This type is characterised by an upper esophageal pouch which ends blindly and a distal tracheoesophageal fistula. Commonly associated diseases are cardiac, renal, vertebral and anal anomalies. The most important intraoperative anaesthesiological complications are acidosis, hypoxaemia, gastric distension, endotracheal tube obstruction, tracheal compression, cardiac arrhythmias and atelectasis. In the presented case an endotracheal tube obstruction with hypercapnia occurred which required a change of the airway. After changing the endotracheal tube the newborn could be ventilated sufficiently. Further postoperative course was uneventful. 相似文献