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1.
A 55-year-old woman with primary (granulomatous) angiitis of the central nervous system in association with non-Hodgkin's lymphoma (mucosa-associated lymphoid tissue type) presented with an acute spinal subdural hemorrhage secondary to rupture of one of several fusiform inflammatory aneurysms of the spinal cord radicular arteries. The literature on hemorrhagic complications, aneurysms, and spinal cord involvement in granulomatous angiitis is reviewed. Recognition of granulomatous angiitis is important, as the condition may be responsive to immunosuppressive therapy.  相似文献   
2.
PURPOSE: We designed a phase I-II trial of three active agents, paclitaxel, ifosfamide, and vinorelbine, in advanced non-small-cell lung cancer (NSCLC) to: 1) define the dose-limiting toxicities (DLT) and maximum tolerated dose (MTD) of paclitaxel with filgrastim (G-CSF) support; and 2) determine the overall response rate and median survival of patients treated on this regimen. PATIENTS AND METHODS: We treated cohorts of patients with stage IIIB or IV NSCLC with ifosfamide 1.2-1.6 g/m2/day x 3 and vinorelbine 20-25 mg/m2/day x 3 and escalating doses of paclitaxel at 100-175 mg/m2 on day 2 with G-CSF support on a 21-day cycle. One prior experimental single-agent chemotherapy regimen was allowed. RESULTS: Fifty-six patients, were enrolled on this trial: 27 on the phase I portion of the study and an additional 29 at the recommended phase II dose (RPTD). Thirteen patients had received prior chemotherapy. Paclitaxel doses of 175 mg/m2 and 150 mg/m2 produced dose-limiting myelosuppression, and the RPTD was determined to be paclitaxel 135 mg/m2 with ifosfamide 1.2 g/m2/day on days 1-3 and vinorelbine 20 mg/m2/ day on days 1-3 with G-CSF support. The overall response rate was 18%, with a median survival of 6.1 months. Six of 35 patients (17%) treated at the RPTD achieved a partial response to therapy. Grade IV neutropenia was observed in 19 of 35 patients at this dose, with eight patients suffering febrile neutropenia. CONCLUSIONS: This non-cisplatin-containing three-drug regimen has substantial toxicity and low activity in advanced NSCLC, and does not seem to improve on prior regimens. It is unclear whether the lack of efficacy relates to an antagonistic reaction between the specific drugs, administration schedule, or to subtherapeutic doses of the individual agents.  相似文献   
3.
We have investigated the visual responses of 184 single units located in the superficial layers of the optic tectum (OT) of the decerebrate, paralysed pigeon. Visual responses were similar to those reported in non-decerebrate preparations; most units responded best to moving visual stimuli, 18% were directionally selective (they had a clear preference for a particular direction of visual stimulus movement), 76% were plane-selective (they responded to movement in either direction in a particular plane). However, we also found that a high proportion of units showed some sensitivity to the orientation of visual stimuli. We examined the effects of extraocular muscle (EOM) afferent signals, induced by passive eye movement (PEM), on the directional visual responses of units. Visual responses were most modified by particular directions of eye movement, although there was no unique relationship between the direction of visual stimulus movement to which an individual unit responded best and the direction of eye movement that caused the greatest modification of that visual response. The results show that EOM afferent signals, carrying information concerning the direction of eye movement, reach the superficial layers of the OT in the pigeon and there modify the visual responses of units in a manner that suggests some role for these signals in the processing of visual information.  相似文献   
4.
Several variations of cache-based checkpointing for rollback error recovery from transient errors in shared-memory multiprocessors have been recently developed. By modifying the cache replacement policy, these techniques use the inherent redundancy in the memory hierarchy to periodically checkpoint the computation state. Three schemes, different in the manner in which they avoid rollback propagation, are evaluated in this paper. By simulation with address traces from parallel applications running on an Encore Multimax shared-memory multiprocessor, we evaluate the performance effect of integrating the recovery schemes in the cache coherence protocol. Our results indicate that the cache-based schemes can provide checkpointing capability with low performance overhead, but with uncontrollable high variability in the checkpoint interval  相似文献   
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6.
Recent research has proposed the use of asphalt and tall-oil-pitch emulsions for stabilizing radioactive contamination deposited on surfaces in urban areas. The objective of this project was to investigate whether surface applied emulsions could capture airborne radioactive particulate. Laboratory experiments included wind-blown particulate capture studies using an acrylic column and particulate retainment experiments using a wind box capable of producing wind speeds of 96?km/h. A probe methodology was developed to relate particulate retainment to a tack force on the emulsion surface. Experiments were also performed to determine the potential for such emulsions to absorb particulate matter into their emulsion matrix. Tall-oil-pitch emulsions outperformed asphalt emulsions in terms of particulate retention, tack force, and the ability to absorb magnesium silicate. Both tall-oil-pitch and asphalt emulsions were capable of extracting 22–24?g?m?2 of powder from particulate-laden airflow. Tall-oil-pitch emulsions were capable of retaining as much as 5–10% of magnesium silicate powder applied (i.e., retainment densities of 10–20?g?m?2) even after seven?days of curing and after applying 96.5?km/h (60?mph) wind. Tall-oil-pitch emulsions were able to absorb surface-applied magnesium silicate (approximately 0.1–0.2?g of magnesium silicate per 1.0?g of emulsion within three?days) into their emulsion matrix, preventing the magnesium silicate from being exposed to the external environment. Initial results with these five different emulsion formulations suggested particulate capture was feasible. Future emulsion formulations (i.e., longer curing times with greater acid concentrations) should be tested to optimize this postdetonation response strategy.  相似文献   
7.
The mass childhood immunization programme has traditionally been viewed as a safe and effective preventative measure by health promoters, primary health care professionals and governments. This consensus has meant that immunization has rarely been viewed as ethically problematic. A number of recent changes in the context of the delivery of health care, particularly the emphasis on consumerism and the effect of the marketization of services, makes timely an examination of ethical, social and political issues. This article examines four main grounds for problematizing the mass childhood immunization programme. These are: clinical research evidence about the safety and efficacy of vaccines; the masking of wider social and political determinants of ill health; the contradictory strictures about collective and individual rights in relation to immunization; and the uniqueness of childhood immunization as a physical intrusion into a healthy body. The implications of these ethical issues are discussed in relation to informed consent and the need for a 'greenfield' review that includes the views of dissenting parents, lawyers and moral philosophers, as well as health professionals.  相似文献   
8.
We have treated 50 patients with stage III, VI malignant tumors confirmed by pathology. The patients were divided into two groups. One group was treated by combination of chemotherapy and traditional Chinese medicine (treatment group); the other only by chemotherapy (control group). The effect of cancer treatment was evaluated according to the criteria of WHO. The results showed that the effective rate was 80% in treatment group and 52% in control group. The pain relieving rate was 68% in treatment group and 40% in control group (P < 0.01). This fact demonstrates that the application of traditional Chinese medicine can invigorate blood circulation, eliminate blood stasis, soften hardness and dissolve the mass, nourish blood and increase vigor. This kind of application can not only enhance the effect of cancer treatment but also increase the cancer pain relieving rate.  相似文献   
9.
This study investigated the developmental changes in the mechanical properties of the respiratory system in growing horses. Pulmonary mechanics and lung volumes were serially measured in anesthetized foals during the first year of life. Quasi-static pressure-volume curves were generated, and functional residual capacity (FRC) was measured using a closed nitrogen equilibration technique. At birth, chest wall compliance normalized to body weight was substantially less than that reported in other less precocious newborn species, while lung compliance normalized to body weight was similar to values reported for other species. Characteristics of the transition from the neonatal to adult respiratory system in the foal included a decrease in the ratios of chest wall to lung compliance (Cw/CL) and the unstressed volume of the chest wall to TLC, and a constant FRC/TLC throughout most of the study period. The somatic growth of the foal and its respiratory system were uneven processes, with increases in lung volume lagging increases in overall body size.  相似文献   
10.
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