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81.
Pyrethrins, complex esters extracted from Chrysanthemum cinerariaefolium, exhibit only minimal in vitro activity against herpes simplex virus (HSV). Employing a guinea pig model of HSV genital infection, no in vivo activity could be demonstrated. Although purported to be an effective remedy for the treatment of genital herpes, we were unable to demonstrate efficacy for either the oral administration of an alcoholic solution of pyrethrins or the topical application of pyrethrins in mineral oil.  相似文献   
82.
Fourteen children with juvenile rheumatoid arthritis and two with ankylosing spondylitis received 29 total hip replacements (THR). The ages at THR were 12 to 18 years, the median duration of prior hip disease was 7.1 years, and the minimum followup was one year (range 1–4 years, median 2.2 years). The primary indication for THR was pain in 5 hips and severe malposition or flexion contractures in 24 hips. (Sixteen of these also had some degree of pain.) All 29 hips demonstrated improved postoperative range of motion, and all were free of pain. In children, active rheumatic disease in other joints, prosthesis longevity, and possible lack of adequate motivation all merit special consideration prior to THR, but the results are encouraging.  相似文献   
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84.
The c-kit receptor ligand functions as a mast cell chemoattractant.   总被引:15,自引:4,他引:15  
Mast cells accumulate at sites of neovascularization, solid tumors, and many immune reactions. Such accumulation requires directed migration of mature mast cells or their precursors. The nature of the chemoattractants that regulate mast cell motility and the identity of the receptors that mediate the chemotactic response are poorly understood. We have tested the ability of stem cell factor (SCF), a mast cell growth factor, to stimulate mast cell migration. Our results show that SCF is a potent mast cell attractant that stimulates directional motility of both mucosal and connective tissue-type mast cells. The activity is potentiated by costimulation with interleukin-3 (IL-3), another mast cell chemoattractant. SCF, a known ligand for the c-kit tyrosine kinase receptor, was unable to stimulate motility in W42 mutant mast cells, which have a defective c-kit tyrosine kinase. However, W42 mast cells were still able to migrate in response to IL-3. These results show that SCF is a chemotactic factor as well as a growth factor and that the c-kit receptor can transduce signals leading to both cell proliferation and increased directional cell motility.  相似文献   
85.
Previous research has affirmed the key role of the physician in the decision to use hospice. Yet at least 1/4 of the physicians who have the opportunity to discuss hospice with a terminally ill patient never do so, and those that do so are selective. The present study used a qualitative approach to investigate the factors considered by the physician when deciding to discuss hospice with a patient. Participants were 17 practicing physicians who had referred patients to the one certified hospice in the geographic area of the study. Data were gathered by means of semi-structured interviews, which were audiotaped and transcribed for thematic analysis. The final categorization of data divided themes along two dimensions: a content dimension and a second dimension called incentives and disincentives. It is proposed that the physician’s proactive stance toward disclosure of the terminal diagnosis and perception of hospice as an opportunity for death with dignity create a culture within which the work that is necessary to make the other factors favorable toward use of hospice is accomplished.  相似文献   
86.
A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas.  相似文献   
87.
McGuire KJ  Chacko AT  Bernstein J 《Orthopedics》2011,34(10):e598-e601
Hospitals with lower costs are not necessarily superior to those that are more expensive, because the more costly institutions might offer better outcomes. The purpose of this study was to consider prices and outcomes in an integrated model and thereby determine if teaching hospitals are cost-effective for the care of hip fractures. We analyzed the claims data of a sample of 18,908 Medicare patients who were admitted to one of 190 acute care hospitals for surgical treatment of a hip fracture. For each hospital, we assessed the relationship between the total per capita Medicare payments over a 6-month period following admission and the 30-day and 6-month mortality. The data were analyzed as a function of hospital type: teaching vs nonteaching. The mean adjusted costs were $5910 per patient higher at teaching hospitals compared to nonteaching hospitals (approximately $24,000 vs $18,000) However, the adjusted 6-month mortality was 1.4% lower at major teaching hospitals. The adjusted incremental cost-effectiveness for teaching hospitals was $422,143 per life saved. By that measure, each life saved would have to yield nearly 8.5 additional quality-adjusted life years (QALY) to attain the $50,000/QALY standard thought to represent cost-effective spending, an unlikely target given the age of the typical hip fracture patient. Nonetheless, because teaching hospitals are more expensive than non-teaching hospitals, a relatively small cut in the overall cost of care at teaching hospitals could dramatically decrease the marginal cost of each life saved. The elements of teaching hospital care that improve survival might be identified in further studies and instituted, perhaps, at non-teaching hospitals without greatly increasing their cost structure.  相似文献   
88.
Despite multiple studies, many clinicopathologic issues about chromophobe renal cell carcinoma (RCC) remain contentious; for example, its biological behavior-whether better or similar to papillary RCC, the incidence of sarcomatoid features, and whether pathologic features such as necrosis, nuclear grade, and tumor stage predict worse outcome. We studied 203 consecutive primary chromophobe RCCs resected at our institution in an attempt to answer these and other questions. The tumors showed significant progressive decrease in size and stage (P=0.047 and 0.001) from 1980 to 2000. Five patients had metastasis at presentation, and further disease-specific events (recurrence/metastasis/death due to disease) occurred in 8 more. Only 4 of 203 tumors had sarcomatoid features. Over median follow-up of 6.1 years (range, 0.1 to 18 y), 5-year and 10-year disease-specific events occurred in 3.7% (95% CI, 1.5%, 7.4%) and 6.4% (95% CI, 2.7%, 12.2%) patients. Outcomes showed significant association with tumor size, small-vessel invasion, sarcomatoid features, and microscopic necrosis (P≤0.05 each). pT stage or nodal metastasis tended to show some association, without reaching statistical significance (P=0.05 and 0.06, respectively). A modified tumor grading scheme, somewhat similar to that proposed recently, mitotic index, cytologic eosinophilia, and architecture, were not significantly associated with outcome. In conclusion, sarcomatoid differentiation is quite uncommon in chromophobe RCC. Tumor size, small-vessel invasion, sarcomatoid differentiation, and microscopic necrosis are the only features that are significantly associated with adverse outcome. On the basis of this long follow-up on a large number of cases, chromophobes seem to have better clinical outcomes than those reported for clear cell and papillary RCCs.  相似文献   
89.
OBJECT: The authors prospectively assessed the value of awake craniotomy used nonselectively in patients undergoing resection of supratentorial tumors. METHODS: The demographic features, presenting symptoms, tumor location, histological diagnosis, outcomes, and complications were documented for 610 patients who underwent awake craniotomy for supratentorial tumor resection. Intraoperative brain mapping was used in 511 cases (83.8%). Mapping identified eloquent cortex in 115 patients (22.5%) and no eloquent cortex in 396 patients (77.5%). RESULTS: Neurological deficits occurred in 89 patients (14.6%). In the subset of 511 patients in whom brain mapping was performed, 78 (15.3%) experienced postoperative neurological worsening. This phenomenon was more common in patients with preoperative neurological deficits or in those individuals in whom mapping successfully identified eloquent tissue. Twenty-five (4.9%) of the 511 patients suffered intraoperative seizures, and two of these individuals required intubation and induction of general anesthesia after generalized seizures occurred. Four (0.7%) of the 610 patients developed wound complications. Postoperative hematomas developed in seven patients (1.1%), four of whom urgently required a repeated craniotomy to allow evacuation of the clot. Two patients (0.3%) required readmission to the hospital soon after being discharged. There were three deaths (0.5%). CONCLUSIONS: Awake craniotomy is safe, practical, and effective during resection of supratentorial lesions of diverse pathological range and location. It allows for intraoperative brain mapping that helps identify and protect functional cortex. It also avoids the complications inherent in the induction of general anesthesia. Awake craniotomy provides an excellent alternative to surgery of supratentorial brain lesions in patients in whom general anesthesia has been induced.  相似文献   
90.
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