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排序方式: 共有524条查询结果,搜索用时 15 毫秒
91.
92.
93.
Enzmann DR; Wheat R; Marshall WH; Bird R; Murphy-Irwin K; Karbon K; Hanbery J; Silverberg GD; Britt RH; Shuer L 《Radiology》1985,154(2):393-399
Intraoperative ultrasound (US) was compared to computed tomography (CT) in 41 intracranial and 6 spinal cord tumors. The studies correlated closely except for primary gliomas. Eight of the 22 primary intracranial gliomas (37%), including 1 low-grade and 7 anaplastic tumors, were larger and more extensive on US than on CT. Margins of non-enhanced primary astrocytomas were shown by US but not CT. Four anaplastic tumors (19%) exhibited echogenicity extending beyond the enhanced area. In 4 patients an enhanced lesion contained a lucent center which proved to be echogenic. Low-grade astrocytomas were relatively homogeneous on US, while anaplastic astrocytomas were more inhomogeneous. Cysts could be found in both types of astrocytomas and were often small and multiple. The echo pattern was not helpful in differentiating metastases from primary tumors, although all of them had sharp margins. Sonography of the central nervous system can provide valuable information about tumor morphology and margins. 相似文献
94.
James F. Bishop Richard Kefford Derek Raghavan John Zalcberg Robin Stuart-Harris David Ball Ian N. Olver Michael Friedlander Colin Bull Kally Yuen Jane P. Matthews Alan Zimet 《Cancer chemotherapy and pharmacology》1990,25(5):367-370
Summary The efficacy and toxicity of 120 mg/m2 etoposide and 100 mg/m2 carboplatin given i.v. daily x 3 together with 750 mg/m2 cyclophosphamide and 14 mg/m2 vincristine given i.v. on day 1 (ECCO) in a regimen given every 28 days for 6 courses was assessed in 90 (40 limited stage, 50 extensive stage) previously untreated patients with small-cell lung cancer. Mediastinal irradiation using 50 Gy in 25 fractions was given to limitedstage patients without progression after 3 courses of chemotherapy. Cranial irradiation with 30 Gy in 10 fractions was given to all patients attaining a complete response (CR). Objective responses were seen in 83% [CR, 60%; partial response (PR), 23%] of patients with limited and 76% (CR, 22%; PR, 54%) of those with extensive disease. The median relapse-free survival for objective responders with limited disease was 13.4 months, with a median of 8.0 months for extensive-stage patients. The median relapse-free survival for patients achieving a CR was 13.4 months, with a median of 7.8 months for those undergoing a PR. The median survival was 13.3 months for patients with limited disease, with a median of 9.6 months for those with extensive disease. The median survival following a CR was 18.2 months, with a median survival of 9.9 months for those showing a PR. The combination was well tolerated, with either no nausea or nausea only (WHO grade 0 or 1) in 56% of patients and minimal mucositis, renal toxicity, neurotoxicity or ototoxicity. Neutropenia measuring <1.0×109 WBC/l (WHO grade 3 or 4) was seen in 74% of patients, with two deaths due to infection occurring during neutropenia. Thrombocytopenia of <50×109 platelets/l (WHO grade 3 or 4) occurred in 24% of patients. ECCO is a new, active, welltolerated program for previously untreated patients with small-cell lung cancer.This study was partly supported by David Bull Laboratories, Melbourne, and the Anti-Cancer Council of Victoria 相似文献
95.
Cerebral microgyria, thalamic cell size and auditory temporal processing in male and female rats 总被引:4,自引:2,他引:2
Herman AE; Galaburda AM; Fitch RH; Carter AR; Rosen GD 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(5):453-464
Induction of microgyria by freezing injury to the developing somatosensory
cortex of neonatal rats causes a defect in fast auditory processing in
males, but not in females. It was speculated that early damage to the
cortex has sexually dimorphic cascading effects on other brain regions
mediating auditory processing, which can lead to the observed behavioral
deficits. In the current series of experiments, bilateral microgyri were
induced by placement of a freezing probe on the skulls of newborn male and
female rats, and these animals were tested in adulthood for auditory
temporal processing. Control animals received sham surgery. The brains from
these animals were embedded in celloidin, cut in the coronal plane and the
following morphometric measures assessed: microgyric volume, medial
geniculate nucleus (MGN) volume, cell number, and cell size, and, as a
control, dorsal lateral geniculate nucleus (dLGN) volume, cell number and
cell size. There were no sex differences in the cortical pathology of
lesioned animals. However, microgyric males had more small and fewer large
neurons in the MGN than their sham-operated counterparts, whereas there was
no difference between lesioned and sham-operated females. There was no
effect on dLGN cell size distribution in either sex. Microgyric males were
significantly impaired in fast auditory temporal processing when compared
to control males, whereas lesioned females exhibited no behavioral
deficits. These results suggest that early injury to the cerebral cortex
may have different effects on specific thalamic nuclei in males and
females, with corresponding differences in behavioral effects.
相似文献
96.
Pond GD; Seeley GW; Ovitt TW; Chernin MM; Yoshino MT; Roehrig H; McIntyre KE 《Radiology》1989,170(2):367-370
This prospective study compared images obtained with a photostimulable imaging plate with matched images obtained with a conventional screen-film combination in 26 patients undergoing intraoperative arteriography. Diagnostic accuracy of the two techniques was assessed objectively, and image quality was assessed subjectively. In 16 patients (62%), the radiation exposure was reduced by 50% for the imaging plate technique by decreasing the mAs level generally used for the screen-film combination. Because of the dynamic range of the imaging plate system, no repeat examinations were necessary, while 12% of the screen-film studies had to be repeated because of over- or under-penetration. Imaging plate studies required 6% more time for processing than screen-film studies. Receiver-operating-characteristic analysis indicated no difference in diagnostic accuracy between the two imaging techniques. Subjective evaluation also revealed no difference in observer preference for imaging plate or screen-film studies. The imaging plate technique is an excellent alternative to screen-film studies in the operating room. 相似文献
97.
98.
Mediastinal Hodgkin disease in children: response to therapy 总被引:1,自引:0,他引:1
99.
Sara Goodman Zimet EdD Gordon K. Farley MD 《Child psychiatry and human development》1993,23(3):183-202
Reading, spelling, and arithmetic achievement of children treated in a day psychiatric hospital was examined over time. The results indicated that the majority of children fell in the average and above achievement group and progressed evenly over time. Almost none got worse and only a few made large gains. Organic impairment ratings appeared to distinguish the three performance groups within each subject area.This research was supported in part by an award from NIMH Grant No. 1 R03 MH40993-01A1 and from a grant from the Developmental Psychobiology Research Group Endowment Fund No. 1344, provided by the Grant Foundation. The authors would like to thank the staff members and children at the Day Care Center for their cooperation, and Nanci Avitable for her assistance in analyzing the data. 相似文献
100.
Anterior temporal lobes and hippocampal formations: normative volumetric measurements from MR images in young adults 总被引:25,自引:0,他引:25
Jack CR Jr; Twomey CK; Zinsmeister AR; Sharbrough FW; Petersen RC; Cascino GD 《Radiology》1989,172(2):549-554
Volumes of the right and left anterior temporal lobes and hippocampal formations were measured from magnetic resonance images in 52 healthy volunteers, aged 20-40 years. Subjects were selected by age, sex, and handedness to evaluate possible effect of these variables. Data were normalized for variation in total intracranial volume between individuals. Right-left asymmetry in the volumes of the anterior temporal lobes and hippocampal formations was a normal finding. The anterior temporal lobe of the non-dominant (right) hemisphere was larger than the left by a small (mean right-left difference, 2.3 cm3) but statistically significant amount (P less than .005) in right-handed subjects. No significant effect of age or sex was seen in normalized right or left anterior temporal lobe volume. The right hippocampal formation was larger than the left for all subjects by a small (mean right-left difference, 0.3 cm3) but statistically significant amount (P less than .001). No effect of age, sex, or handedness was seen in normalized hippocampal formation volumes. 相似文献