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991.
Cancer chemotherapy is associated with a wide range of vascular toxicities, which may be related to endothelial cell damage by these agents. The authors describe a patient with Hodgkin's disease who developed an atypical aortic dissection while receiving MOPP/ABV chemotherapy (nitrogen mustard, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, and vinblastine). They would place aortic dissection on the list of potential vascular complications associated with antineoplastic agents.  相似文献   
992.
993.
After sciatic transection a strong decrease in immunoreactivity occurred, starting at 2 days. After 6, 10, 14, and 20 days survival only 5% of the sciatic motoneurons were strongly labeled for GluR2/3 against 80% in the control situation. From Day 20, GluR2/3 labeling started to increase again, reaching near normal levels at Day 80 after sciatic transection. In contrast, after sciatic crush, the decrease in GluR2/3 labeling in motoneurons was less pronounced and returned to normal in 30 days. In all animals, the GluR1 and GluR4 labeling of motoneurons remained unchanged after sciatic transection or crush. It is concluded that sciatic nerve injury leads to a strong, time-dependent decrease in the expression of GluR2 and 3 subunits in the corresponding motoneurons. As a consequence, AMPA receptors with a different subunit composition may be assembled, leading to a change in the functional properties of these receptors. Moreover, if they lack the GluR2 subunit, they may become calcium permeable.  相似文献   
994.
Ideomotor apraxia, disordered movement execution to command, commonly follows left-hemisphere damage, implying left-hemisphere dominance for certain kinds of movements. To delineate this dominance we used different command modalities to elicit meaningful movements and tested imitation of nonsense movements. Twenty-seven patients with unilateral hemispheric stroke and 10 age-matched controls were evaluated. Patients with left-hemisphere damage performed both meaningful and nonsense movements poorer than the other study groups; thus, the meaningfulness of the movements is irrelevant for the left-hemisphere motor dominance. The performance varied, however, with the command modality and movement type. Based on this and earlier studies we posit that the left-hemisphere motor dominance is determined by the artificiality of the test situation (it concerns movements performed to command and out of the natural context) and increased spatial and temporal complexity of the demanded movements. No association between the lesion locus within the left hemisphere and the severity of the ideomotor apraxia was found.  相似文献   
995.
996.
PROBLEM/CONDITION: Malaria is caused by infection with one of four species of Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, and P. malariae ), which are transmitted by the bite of an infective female Anopheles sp. mosquito. Most malarial infections in the United States occur in persons who have traveled to areas (i.e., other countries) in which disease transmission is ongoing. However, cases are transmitted occasionally through exposure to infected blood products, by congenital transmission, or by local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to adapt prevention recommendations. REPORTING PERIOD COVERED: Cases with onset of symptoms during 1994. DESCRIPTION OF SYSTEM: Malaria cases confirmed by blood smear are reported to local and/or state health departments by health-care providers and/or laboratories. Case investigations are conducted by local and/or state health departments, and the reports are transmitted to CDC through the National Malaria Surveillance System (NMSS), which was the source of data for this report. Numbers of cases reported through NMSS may differ from those reported through other passive surveillance systems because of differences in the collection and transmission of data. RESULTS: CDC received reports of 1,014 cases of malaria with onset of symptoms during 1994 among persons in the United States or one of its territories. This number represented a 20% decrease from the 1,275 cases reported for 1993. P. vivax, P. falciparum, P. malariae, and P. ovale accounted for 44%, 44%, 4%, and 3% of cases, respectively. More than one species was present in five persons (<1% of the total number of patients). The infecting species was not determined in 50 (5%) cases. The number of reported malaria cases in U.S. military personnel decreased by 86% (i.e., from 278 cases in 1993 to 38 cases in 1994). Of the U.S. civilians who acquired malaria during travel to foreign countries, 18% had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Five persons became infected while in the United States; the infection was transmitted to two of these persons through transfusion of infected blood products. The remaining three cases, which occurred in Houston, Texas, were probably locally acquired mosquitoborne infections. Four deaths were attributed to malaria. INTERPRETATION: The 20% decrease in the number of malaria cases from 1993 to 1994 resulted primarily from an 86% decrease in cases among U.S. military personnel after withdrawal from Somalia. Because most malaria cases acquired in Somalia during 1993 resulted from infection with P. vivax, there was a proportionately greater decrease during 1994 in the number of cases caused by P. vivax relative to those caused by P. falciparum. ACTIONS TAKEN: Additional information was obtained concerning the four fatal cases and the five cases acquired in the United States. Malaria prevention guidelines were updated and distributed to health-care providers. Persons traveling to a geographic area in which malaria is endemic should take the recommended chemoprophylactic regimen and should use protective measures to prevent mosquito bites. Persons who have a fever or influenza-like illness after returning from a malarious area should seek medical care; medical evaluation should include a blood smear examination for malaria. Malarial infections can be fatal if not promptly diagnosed and treated. Recommendations concerning prevention and treatment of malaria can be obtained from CDC.  相似文献   
997.
This study was designed to determine the efficacy of saline as an epidural top-up to prolong spinal anesthesia during combined spinal-epidural anesthesia (CSEA). Eight volunteers received three separate CSEAs with intrathecal lidocaine (50 mg). After two-segment regression, each subject received either a saline (10 mL), lidocaine 1.5% (10 mL), or control sham (0.5 mL saline) epidural injection in a randomized, double-blind, triple cross-over fashion. Sensory block was assessed by pinprick and tolerance to transcutaneous electrical stimulation (TES) equivalent to surgical stimulation at the knee and ankle. Motor strength was assessed with iso-metric force dynamometry. Data were analyzed with a repeated measures analysis of variance and a paired t-test. Sensory block to pinprick was prolonged in the thoracolumbar dermatomes only by lidocaine (P < 0.05). Neither lidocaine nor saline prolonged the duration of tolerance to TES at the tested sites. Instead, saline decreased the duration of tolerance to TES by 20 and 24 min at the knee and ankle (P < 0.05). Recovery from motor block at the quadriceps was prolonged by an epidural injection of lidocaine (P < 0.05). We conclude that when 10 mL of epidural saline is administered after two-segment regression, it is an ineffective top-up and may decrease the duration of spinal anesthesia during CSEA.  相似文献   
998.
999.
BACKGROUND: We considered whether it is more practical to amputate the toe of a diabetic patient with osteomyelitis and good circulation or to treat the patient with antibiotics for a prolonged period. METHODS: We undertook a retrospective study of 141 diabetic patients who had undergone a toe-ray amputation for proven or documented osteomyelitis. RESULTS: The mean ankle/brachial index of all patients was 0.81 (range, 0.68 to 1.14); the mean functional days lost on antibiotic therapy was 39 (range, 7 to 84 days). The cost of 6 to 8 weeks of preoperative antibiotic therapy was $900 to $2240 (mean, $1440). CONCLUSIONS: Diabetic patients with good circulation and osteomyelitis of the toe may benefit from prompt toe amputation.  相似文献   
1000.
BACKGROUND: A comparative study was performed between patients with exocrine pancreatic insufficiency after conventional pancreatoduodenectomy (Whipple's procedure) and pylorus-preserving pancreatoduodenectomy (PPPD). In these patients the pharmacodynamics of 2-mm enteric-coated pancreatin microspheres (ECPMs) and their gastric transit time in relation to that of a solid meal were investigated. The efficacy of ECPM preparations may differ after Whipple's procedure compared with PPPD, because the latter procedure does not include gastrectomy. METHODS: Gastric transit was assessed by double-isotope scintigraphy. A pancake meal was labelled with 99mTc. ECPMs were cold-labelled with 170Er and neutron activated shortly before ingestion to enable imaging with a gamma camera. Intraluminal pancreatic enzyme activity was assessed during a 6-h period with two indirect tests: the cholesteryl [14C]octanoate breath test and the N-benzoyl-L-tyrosyl-p-aminobenzoic acid-p-aminosalicylic acid (NBT-PABA-PAS) test. RESULTS: In patients who had Whipple's procedure, the gastric transit time of ECPMs and of the pancake meal was not significantly different. The outcome of the indirect pancreatic function tests during enzyme supplementation was comparable, and not significantly different, from that in healthy volunteers. In patients who had PPPD, however, the gastric transit time of microspheres was greatly delayed compared with that of the pancake meal (P < 0.05). Improvement in the outcome of the indirect pancreatic function tests during enzyme supplementation was much less and remained well below that of healthy volunteers (P < 0.05). CONCLUSION: In cases of exocrine pancreatic insufficiency after Whipple's procedure, 2-mm ECPM treatment adequately restores pancreatic enzyme activity. Following PPPD, however, ECPM treatment is often ineffective because the microspheres are retained in the stomach. In these patients, use of conventional powdered pancreatin enzyme preparations may improve the efficacy of treatment.  相似文献   
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