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排序方式: 共有493条查询结果,搜索用时 15 毫秒
41.
42.
Gastrointestinal teratomas are uncommon, benign neoplasms that occur primarily in children. A retrospective review of five cases (two gastric, one pancreatic, one mesenteric, and one in the lesser omentum) is presented with emphasis on the computed tomographic and ultrasonographic appearances. Principal findings are a well-defined mass with separate cystic and solid components of varying proportions, discrete areas with densities similar to that of fat, or coarse, globular calcifications within the solid component. Recognition of these findings may allow the radiologist to make a correct preoperative diagnosis of teratoma. 相似文献
43.
Conventional computer-based medical expert systems deliver advice to physicians as written text. While such advice is useful, it has distinct limitations in a visually oriented discipline such as diagnostic radiology, in which decisions often depend on pattern recognition and appreciation of subtle morphologic features. The authors developed a prototype expert computer system, IMAGE/ICON, which displays groups of images sorted into a series of axes based on different ways in which they may be similar. They may share a common feature, group of features, causes, or clinical setting. IMAGE/ICON may display examples of morphologic variations of a dominant finding or a spectrum of abnormalities seen in an specific disease or group of diseases. The system also assembles a written analysis of key features of a case. Such a tool may be useful as a diagnostic aid or for continuing medical education. It is likely to have particular impact in the form of an intelligent radiologic workstation, as picture archiving and communication systems become available. 相似文献
44.
Mueller PR; Silverman SG; Tung G; Brink JA; Cardenosa G; Saini S; Forman BH; Hahn PF 《Radiology》1989,173(1):278-279
A new tray has been designed for use during procedures involving needles and other sharp objects. The tray includes a foam adhesive pad, marked into 10 sections, into which the sharp objects can be placed point first. After the procedure, the objects can be safely withdrawn by their handles and then discarded. The tray has been used in more than 250 procedures. 相似文献
45.
The Viral Activation Transfusion Study (VATS): rationale, objectives, and design overview 总被引:1,自引:0,他引:1
46.
Monitoring for undertransfusion 总被引:1,自引:0,他引:1
BACKGROUND: Most published reviews and audits of blood and blood component transfusion have focused on the issue of overtransfusion and on the inappropriate use of red cell components. There is growing concern that efforts to curb unnecessary transfusions may result in a trend toward undertransfusion of patients. There is little published information that addresses this issue or the magnitude of this practice. STUDY DESIGN AND METHODS: Undertransfusion was evaluated by examining the transfusion records from a 3-month period for 55 patients who met the study criteria of having either a hemoglobin level < 7 g per dL or a platelet count of < 10 × 10(9) per L. If the identified patient did not receive a transfusion within 24 hours of the reported hemoglobin level or platelet count, the medical record was reviewed by a resident physician. RESULTS: A total of 213 individual hemoglobin levels and platelet counts, representing the 55 patients, met our transfusion criteria. All except 8 of the identified patients received red cells and/or platelet transfusions. Reasons for not transfusing red cells included the patient's response to nutritional support and iron supplementation, refusal of blood, and noncompliance. Reasons for not transfusing platelets included falsely low platelet count because of platelet clumping in vitro, contraindication based on clinical diagnosis (e.g., immune thrombocytopenic purpura), and the patient's death before transfusion. CONCLUSION: Red cell and platelet transfusions were appropriately ordered for all patients who met the transfusion criteria. Undertransfusion is not a problem at this institution according to the criteria established. It is recommended that other institutions expand their blood utilization audits to include investigation for evidence of undertransfusion. Further research regarding the issue of undertransfusion is warranted and could be expanded to include other components. 相似文献
47.
Oral sumatriptan in the acute treatment of migraine and migraine recurrence in general practice 总被引:1,自引:0,他引:1
Scott RJ; Aitchison WR; Barker PR; McLaren GI 《QJM : monthly journal of the Association of Physicians》1996,89(8):613-622
We investigated the efficacy, safety and tolerability compared with placebo
of a second dose of oral sumatriptan 100 mg in 1349 general practice
patients who had already treated a moderate or severe migraine headache
with 100 mg sumatriptan 4 h earlier. Headache was relieved by the first
sumatriptan dose in about 70% of patients, but the second dose did not
produce significantly more relief than placebo, either in nonresponders or
in the group as a whole, nor did it reduce other symptoms (photophobia,
nausea, vomiting, etc,) at 8 h, or influence the incidence of headache
recurrence. The drug was well-tolerated, and a further single dose was
effective in treating recurrence after initial relief. A single 100 mg dose
of sumatriptan is an effective acute treatment for migraine. A second dose
should be reserved for treating headache recurrence.
相似文献
48.
Kejia Cai Ravi PR Nanga Lisa Lamprou Claudia Schinstine Mark Elliott Hari Hariharan Ravinder Reddy C Neill Epperson 《Neuropsychopharmacology》2012,37(13):2764-2771
Gamma-aminobutyric acid (GABA) and glutamate are implicated in numerous neuropsychiatric and substance abuse conditions, but their spectral overlap with other resonances makes them a challenge to quantify in humans. Gabapentin, marketed for the treatment of seizures and neuropathic pain, has been shown to increase in vivo GABA concentration in the brain of both rodents and humans. Gabapentin effects on glutamate are not known. We conducted a gabapentin (900 mg) challenge in healthy human subjects to confirm and explore its effects on GABA and glutamate concentrations, respectively, and to test the ability of single voxel localized proton magnetic resonance spectroscopy (1H-MRS) to reliably measure GABA and glutamate in the visual cortex at the ultra-high magnetic field of 7 Tesla. Reproducibility of GABA and glutamate measurements was determined in a comparison group without drug twice within day and 2 weeks apart. Although GABA concentration changes were small both within day (average 5.6%) and between day (average 4.8%), gabapentin administration was associated with an average increase in GABA concentration of 55.7% (6.9–91.0%). Importantly, drug-induced change in GABA levels was inversely correlated to the individual''s baseline GABA level (R2=0.72). Mean glutamate concentrations did not change significantly with or without drug administration. In conclusion, localized 1H-MRS at 7 Tesla can be successfully applied to the measurement of GABA concentration and is sensitive to acute drug-induced changes in cortical GABA. Whether baseline GABA concentrations predict clinical efficacy of gabapentin is an area worthy of exploration. 相似文献
49.
Endoscop c manometry of sphincter of Oddi(SO)and serumlevels of gastrin,glucagon,and somatostatin were measured in patients withpostcholecystectomy syndrome(n=12),asymptomatic cholecystectomised pa-tients(n=6),and controlled subjects(n=14).Pentagastrin-stimulated gastricacid secretion test was also performed in part of patients who had symptoms orno symptoms after gallbladder resection.The results showed that the patientsof symptomatic group had hypertonic dyskinesia of SO as shown by deep andwide waves superimposed on high basal pressure plateau of SO.The symptoma-tic group also had a higher serum level of gastrin and a greater BAO than tho-se of other two groups.No difference of serum levels of glucagon and soma-tostatin was found among these three groups.The hypertonic dyskinesia of SOand hypergastrinemia are considered as possibly important factors in the patho-genesis of postcholecystectomy syndrome. 相似文献
50.
We examined if rat myometrial cells in culture generate nitric oxide (NO)
and express various isoforms of NO synthase (NOS). Myometrial cells
isolated from rats on day 18 of gestation were incubated with various
stimulators and inhibitors of NOS for 24 and 48 h, and NO production was
evaluated by measuring nitrites in the media and NOS proteins in the cell
lysates. NO was produced by myometrial cells and its production inhibited
by N(G)-methyl-L-arginine (L-NMMA). This inhibition was reversed by
L-arginine (3 mM). Interleukin-1beta (IL- 1beta) significantly stimulated
NO production, in a dose-dependent manner. The IL-1beta-stimulated NO
production was inhibited by the NOS inhibitor, L-NMMA, whose effects were
reversed by L-arginine. Abundant NOS III protein was detectable in freshly
isolated myometrial cells, and this was maintained in culture in the
presence of fetal bovine serum (FBS; 10%). In the absence of FBS, NOS III
levels decreased significantly (by 90%) within 24 h. In contrast, NOS I and
NOS II proteins were undetectable in freshly isolated muscle cells and in
cells cultured without IL-1beta. However, NOS II protein in these cells was
induced by IL-1beta. Thus, NO is produced by myometrial cells through the
NOS III isoform, and the myometrial NO may be important in maintaining
uterine quiescence during pregnancy.
相似文献