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711.
712.
713.
Endotracheal tubes in neonates: sonographic positioning 总被引:3,自引:0,他引:3
Twenty-one real-time sonographic determinations of endotracheal tube tip position were performed in 16 neonates. Findings were compared with those from simultaneously obtained chest radiographs. Relation of the tube tip to the aortic arch provided a reliable method of determination of appropriate position. Optimal tube tip position was seen when the tube tip was 1 cm above the arch. 相似文献
714.
715.
In spite of accumulating evidence on the potent neuromodulatory,
neuroprotective, trophic and memory-enhancing effects of the neuropeptide
substance P (SP) in the cerebral cortex, the excitatory or inhibitory
nature of the cortical SP innervation remains unclear and the postsynaptic
targets of SP fibers are not defined. To obtain further insight into these
issues, we have examined SP-containing axons and their postsynaptic targets
in the prefrontal cortex of adult monkeys with single- and double label
immunocytochemistry combined with light and correlated electron microscopy.
SP fibers in the primate prefrontal cortex, unlike those in the rat cortex,
preferentially innervate cortical layers I, II and upper layer III. Our
results demonstrate for the first time that all SP-immunoreactive boutons
in all cortical layers contain GABA. Of the entire sample of SP boutons,
53% synapse on dendritic shafts, 39% on dendritic spines and 8% on cell
bodies. Another new finding is that synapse-forming SP boutons, in addition
to their known innervation of pyramidal cells, form pericellular baskets
around interneurons in layers II and upper III, a subpopulation of which
contains calbindin D28k. Finally, the study also revealed that SP boutons
frequently participate in 'synaptic triads' with spines which receive
another (asymmetric, putatively excitatory amino acid-utilizing) synapse.
Our findings indicate that SP/GABA axons in the primate prefrontal cortex
modulate excitatory amino acid- mediated neurotransmission and control
feed-forward disinhibitory GABAergic circuits in supragranular cortical
layers.
相似文献
716.
Neutrophils were examined for their ability to recognize and ingest beads coated with amino-derivatives of glucose, mannose, and galactose. Radioactive or fluorescent beads coated with any of the three sugars were ingested to an extent three times that observed with albumin- coated beads. Enhancement of ingestion of sugar-coated beads was much more evident when examined by electron micrographic studies. Inclusion of glucose or mannose in the medium with glucose- or mannose-coated beads caused a dose-dependent reduction of ingestion to control levels, but ingestion of galactose-coated beads was poorly inhibited. Similarly, galactose or fucose (6-deoxy-galactose) markedly inhibited ingestion of galactose-coated beads, but caused only a slight decrease in ingestion of glucose- or mannose-coated beads. Thus, neutrophils possess carbohydrate-binding membrane structures that can mediate recognition and ingestion of sugar-coated beads. Such carbohydrate recognition systems may underlie certain interactions of neutrophils and other surfaces. 相似文献
717.
Cerebral astrocytomas: histopathologic correlation of MR and CT contrast enhancement with stereotactic biopsy 总被引:18,自引:0,他引:18
Earnest F th; Kelly PJ; Scheithauer BW; Kall BA; Cascino TL; Ehman RL; Forbes GS; Axley PL 《Radiology》1988,166(3):823-827
Gadolinium-labeled diethylenetriaminepentaacetic acid was used as a contrast agent for stereotactic magnetic resonance (MR) imaging in six selected patients with brain tumors who underwent stereotactic biopsy. Regions of contrast enhancement demonstrated by computed tomography (CT) and MR imaging in four of the six patients correlated with areas of malignant neovascularity and endothelial proliferation within solid tumor. Radiation necrosis produced contrast enhancement indistinguishable from that of recurrent neoplasm. Isolated tumor cells within intact white matter were identified in biopsy specimens obtained outside of regions that were depicted as abnormal by contrast material-enhanced CT, as well as by precontrast and postcontrast T1- and T2-weighted MR images. 相似文献
718.
719.
Abdominal CT scans were reviewed in a series of 53 patients who had abdominal pain without objective physical, radiographic, or laboratory abnormalities. Forty patients presented with abdominal pain alone, while the remaining patients had abdominal pain associated with nausea, vomiting, or mild weight loss. Abdominal CT scans in all patients were interpreted as normal. In all but one patient, the final diagnosis was an insignificant benign condition. One patient had a pancreatic carcinoma discovered at surgery one month after the CT scan was obtained. The patients were followed up for 6 to 12 months to confirm absence of significant disease. Our analysis suggests a very low yield from abdominal CT in patients with abdominal pain and no other objective findings. 相似文献
720.
Endometriosis detection by US with laparoscopic correlation 总被引:1,自引:0,他引:1
Endometriosis is a common cause of female infertility. It may affect as many as 40% of infertile women and may be the sole contributing factor to infertility in 15%. A study was undertaken to determine the usefulness of the routine pelvic ultrasound (US) examination in the detection of endometriosis by correlating pelvic US findings with laparoscopic findings in 85 patients who underwent both examinations. Forty-eight patients (56.5%) had no laparoscopic evidence of endometriosis, and 37 patients (43.6%) had endometriosis. Eight of the patients had abnormal sonograms; of these patients, only four had sonographic abnormalities that corresponded to laparoscopically identified endometriosis. Thus, US was successful in detecting endometriosis in only four (10.8%) of 37 patients. US is neither sensitive nor specific in diagnosing endometriosis. Furthermore, we believe that US does not have a significant role in the diagnosis or management of endometriosis in patients in whom a pelvic mass or other obvious pelvic abnormality is not suspected. 相似文献