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41.
OBJECTIVE: The authors describe their experience with left ventricular assist-device (LVAD) recipients undergoing noncardiac surgery and delineate surgical, anesthetic, and logistic factors important in the successful intraoperative management of these patients. SUMMARY BACKGROUND DATA: Left ventricular assist-devices have become part of the armamentarium in the treatment of end-stage heart failure. As the numbers of patients chronically supported with long-term implantable devices grows, general surgical problems that are commonly seen in other hospitalized patients are becoming manifest. Of particular interest is the intraoperative management of patients undergoing elective noncardiac surgical procedures. METHODS: The anesthesia records and clinical charts were reviewed for eight ventricular assist-device recipients undergoing general surgical procedures between August 1, 1990 and August 31, 1994. RESULTS: A total of 12 procedures were performed in 6 men and 2 women averaging 52.7 years of age. Mean time elapsed from device implantation to operation was 68 +/- 35 days. Conventional inhalational and intravenous anesthetic techniques were well tolerated in these patients undergoing diverse surgical procedures. No perioperative mortality was observed. Five of eight patients went on to successful cardiac transplantation. CONCLUSIONS: Hemodynamic recovery after LVAD insertion has defined a new group of patients who develop noncardiac surgical problems often seen in other critically ill patients. Recognition of the unique potential problems that the LVAD recipient may encounter in the perioperative period--in particular patient positioning, device limitations, and fluid and inotropic management--will ensure an optimal surgical outcome for LVAD recipients undergoing noncardiac surgery.  相似文献   
42.
Patients who had undergone unilateral temporal lobe surgery (right or left temporal lobectomy or amygdalo-hippocampectomy) for intractable temporal lobe epilepsy, and normal control subjects, completed two questionnaires about everyday memory, the Subjective Memory Questionnaire (SMQ) and the Everyday Memory Questionnaire (EMQ). Relatives/close friends completed suitably adapted versions of these questionnaires about the patient. Patients who had undergone right and left temporal lobectomy rated themselves, and were rated by relatives/friends as having worse memories than controls on both the SMQ and EMQ. Individual items on both questionnaires differentiated between the memory abilities of the five groups. Age at surgery was correlated with one measure of everyday memory for the right temporal lobectomy group, and seizure frequency was correlated with memory performance for the amygdalo-hippocampectomy groups. Issues concerning validity and accuracy of rating memory lapses are discussed.  相似文献   
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In order to screen for fetal neural tube defects and chromosome abnormalities, amniocentesis was carried out in 334 women with insulin-dependent diabetes mellitus (IDDM) between 1979 and 1987. Two cases (0.6%; 95% confidence limits 0.1-2.2%) of fetal chromosome abnormality were found: one case of Klinefelter's syndrome and one case of de novo translocation. This is comparable to the overall incidence of chromosome abnormality found at birth and is also comparable to the incidence of fetal chromosome abnormality (1.0%) found by amniocentesis at our Department in a group of 2,264 young non-diabetic women with little risk of contracting genetic disorders. The results suggest that maternal IDDM does not increase the risk of fetal chromosome abnormality and consequently screening by amniocentesis for chromosome abnormalities among diabetic women does not seem to be indicated.  相似文献   
46.
The delivery of therapeutic genes to primary brain neoplasms opens new opportunities for treating these frequently fatal tumors. Efficient gene delivery to tissues remains an important obstacle to therapy, and this problem has unique characteristics in brain tumors due to the blood-brain and blood-tumor barriers. The presence of endothelial mitogens and vessel proliferation within solid tumors suggests that genetically modified endothelial cells might efficiently transplant to brain tumors. Rat brain endothelial cells immortalized with the adenovirus E1A gene and further modified to express the beta-galactosidase reporter were examined for their ability to survive implantation to experimental rat gliomas. Rats received 9L, F98, or C6 glioma cells in combination with endothelial cells intracranially to caudate/putamen or subcutaneously to flank. Implanted endothelial cells were identified by beta-galactosidase histochemistry or by polymerase chain reaction in all tumors up to 35 days postimplantation, the latest time examined. Implanted endothelial cells appeared to cooperate in tumor vessel formation and expressed the brain-specific endothelial glucose transporter type 1 as identified by immunohistochemistry. The proliferation of implanted endothelial cells was supported by their increased number within tumors between postimplantation days 14 and 21 (P = 0.015) and by their expression of the proliferation antigen Ki67. These findings establish that genetically modified endothelial cells can be stably engrafted to growing gliomas and suggest that endothelial cell implantation may provide a means of delivering therapeutic genes to brain neoplasms and other solid tumors. In addition, endothelial implantation to brain may be useful for defining mechanisms of brain-specific endothelial differentiation.  相似文献   
47.
BACKGROUND. This study reports the barriers and challenges for hospital tobacco control efforts after the institution of smoke-free policies. METHODS. Surveys of employees and inpatients of five hospitals in Augusta, Georgia, were conducted and evaluated 4 months after joint hospital implementation of smoke-free policies. A random sample of 1997 employees and a convenience sample of 517 inpatients returned usable surveys. RESULTS. Although attitudes to the hospital bans on smoking reflected strong support for smoke-free policies, four out of five hospitals reported significant implementation problems. Despite the bans, 49% of patients who were smokers continued to smoke while hospitalized, and almost one half of all hospitalized smokers had received no advice to quit smoking from a physician or a nurse since admission. Employees and patients both agreed that the smoke-free policies had benefited employees more than patients. CONCLUSIONS. Despite achieving a smoke-free status, there are many challenges that remain for comprehensive hospital tobacco-control efforts. Hospitals and health care professionals must remain particularly alert and attentive to the needs of patients and employees still addicted to tobacco.  相似文献   
48.
States of phosphorylation of neurofilament proteins were examined in the perikarya of rat sensory and motor neurons between 3 and 28 d following either a distal transection [6-7 cm from the L4-L5 dorsal root ganglia (DRG)] or a proximal transection (1-2 cm from the L4-L5 DRG) of the sciatic nerve. Paraffin sections of the right (experimental) and left (control) L4 and L5 DRG from animals with unilateral transection of the right distal sciatic nerve were stained immunocytochemically with monoclonal antibodies to phosphorylation-dependent (NF-P), dephosphorylation-dependent (NF-dP), or phosphorylation-independent (NF-ind) epitopes on the largest (NF200), mid-sized (NF150), or smallest (NF68) neurofilament protein subunits. Increased immunoreactivity to NF-P on NF200 and NF150 was detected in experimental DRC at 10 d, peaking by 20 d, and declining to near control levels by 28 d. Conversely, immunoreactivity to NF-dP declined in experimental DRG beginning at 6 d, reaching a maximum decline at 10-16 d, and returning to near control levels by 28 d. Immunocytochemical changes were confirmed with biochemical studies on tissue homogenates that demonstrated an increase of immunoreactivity to NF-P and a decrease of reactivity to NF-dP in the experimental DRG. Changes in immunoreactivities to NF-P and NF-dP were observed only in the perikarya of large neurons and were closely associated with chromatolytic changes in these neurons. Marked enhancement of chromatolysis, as well as the immunoreactivities to NF-P and NF-dP, occurred following a proximal (left side) versus distal (right side) transection in the same animal.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
49.
Samples from fibrotic lung lesions greater than 1 cm in diameter macroscopically (by definition, massive fibrosis; MF) were taken from the lungs of 9 randomly selected post-mortem cases of mine workers all showing a background of a pneumoconiosis. These samples were studied histologically, biochemically, and by X-ray diffraction and electron microscopy. As controls for the biochemical and X-ray diffraction investigations, nonfibrosed lung tissue was taken from the same specimens. The findings suggest that the higher quartz content may be the primary cause responsible for the MF formation in this series of cases, while other factors such as tuberculosis may play a part according to some relevant literature on MF. Although an area of MF appears macroscopically to be a solid lesion, on microscopy this is not the case and the lesion is composed of dense and sparse collagen bundles and cellular elements.  相似文献   
50.
We evaluated the relative contribution of plain radiographs and computed tomography to the assessment of fracture healing under experimental circumstances. In 15 sheep, we performed midshaft femoral osteotomies and internal fixation of the resultant segmental fractures. Radiographs were obtained preoperatively and immediately postoperatively. Animals were sacrificed at 3 weeks, 6 weeks, 12 weeks, 24 weeks, and 36 weeks after surgery, and the femoral specimens radiographed. After removal of the internal fixation devices, computed tomographic scans of the specimens were performed.By 3 weeks, callus was visible, but at 6 weeks, a trabecular pattern in the callus was seen on plain films but not on computed tomography. There was progressive organization of the callus on both studies. At 24 weeks, computed tomography demonstrated fracture lines not seen due to overlying callus on plain films and also more accurately showed incomplete union. By 36 weeks, healing was essentially complete according to both modalities, although there still were small gaps in the callus detectable on computed tomography but not on plain films.Computed tomography may be of value in the evaluation of fractures of long bones in those cases in which clinical examination and plain radiographs fail to give adequate information as to the status of healing.  相似文献   
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