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991.
992.
In a prospective study, the effect of infusion of a low-density contrast material was evaluated as an adjunct to high-density, double-contrast imaging of the sigmoid colon. After double-contrast barium enema (DCBE) study, 52 consecutive patients with sigmoid diverticulosis received an additional 500-750-mL enema either with water or a 1.5% barium suspension for computed tomography. Rectosigmoid radiographs were evaluated for luminal distention, visualization of the interhaustral space, definition of diverticula, and interpretation of polypoid defects. While double-contrast views were excellent in 21% of patients, improvement in multiple factors by water or 1.5% barium flush resulted in improved sigmoid images in 65% and 75% of patients, respectively. Polyps were confirmed and artifactual defects confidently excluded. Sigmoid flush, particularly with low-density barium, is a simple adjunct to DCBE study that improves visualization of the diverticular sigmoid and increases interpretive confidence.  相似文献   
993.
St. John  JN; Palmaz  JC 《Radiology》1986,158(1):119-123
Anteroposterior radiographs of the fully flexed and slightly externally rotated elbow were obtained in 122 cases of cubital tunnel syndrome (CUTS) and in 33 normal elbows. Medial trochlear lip osteophytes were not found in the studies of normal elbows but were noted in 20% of ulnar nerve entrapment cases. Medial incongruity between the trochlea and the olecranon greater than or equal to 5 mm was found in 29% of CUTS cases and in 6% of normal elbows. The presence of posttraumatic elbow-joint deformities seen on radiographs correlated significantly with the degree of clinical involvement. Depth and area measurements of ulnar nerve compression, performed using a line-art representation of the radiographs, showed a significant (P less than .0001) correlation between decrease in the area of the cubital tunnel and ulnar innervated muscle atrophy. These findings confirm the importance in this syndrome of both osteoarthritis and incongruity of the medial structures of the elbow joint.  相似文献   
994.
We describe a patient who had cryptosporidiosis and cytomegalovirus infection of the gastric antrum that was initially detected on computed tomography (CT) scans. CT may be useful in the evaluation of immunocompromised patients with diarrheal illness, as well as in the assessment of the gastrointestinal tract.  相似文献   
995.
Whitin  JC; Takahashi  K; Cohen  HJ 《Blood》1987,69(3):762-768
The effect of concanavalin A (Con A) on the concentration of ionized intracellular calcium [( Cai++]) in human granulocytes (PMN) was monitored using the fluorescent calcium indicator and chelator, Quin2. The addition of Con A to PMN resulted in a rise in [Cai++] that was markedly enhanced by the presence of Ca++ in the external buffer. The onset of the increment in [Cai++] preceded the onset of O2- production. The rise in [Cai++] induced by Con A is not transient, with a new, higher steady-state level of [Cai++] being attained within five minutes. The addition of alpha-methylmannoside (alpha-MM) one minute after Con A resulted in the return of [Cai++] to the original baseline level and the cessation of O2- production. The addition of a second stimulus (such as arachidonic acid) to these cells resulted in a second increment in [Cai++] and the return of O2- production. Thus the rise in [Cai++] induced by Con A is tightly coupled to the activation, inactivation, and reactivation of the O2- generating system by Con A. Further experiments were undertaken to assess the possible requirement for the rise in [Cai++] in the activation of PMN by Con A. PMN could be depleted of Cai++ by loading with Quin2 in the absence of extracellular Ca++. These Ca++- depleted PMN can be induced to produce O2- after treatment with PMA but not with Con A. The addition of Ca++ to Ca++ - depleted PMN results in a return of [Cai++] to the normal resting level of Ca++ -replete PMN. The time required to return to baseline is a function of the concentration of intracellular Quin2. The addition of Ca++ to Ca++ -depleted, Con A-treated PMN results in the elevation of [Cai++] and the production of O2-. Over a tenfold range of intracellular Quin2 concentration, the onset of O2- production always occurred at [Cai++] that were less than the normal resting level. Thus, activation of the O2- generating system by Con A can occur at [Cai++] which are much lower than the incremental level induced by Con A in Ca++ -replete PMN. Supporting this is the observation that only a very small increment in [Cai++] is induced by Con A in PMN cytoplasts, even though Con A could induce O2- production in the Quin2-loaded cytoplasts.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
996.
997.
998.
Maglinte  DD; Lappas  JC; Chernish  SM; Anger  RT  Jr; Miller  RE 《Radiology》1985,157(2):535-536
Artifacts related to barium flow during double-contrast esophagography may obscure mucosal surface details. Double-contrast esophagograms with flow artifacts of 35 patients were evaluated to determine the effect on radiographic interpretation and to assess the method of examination. Initial radiographs obtained during swallowing of barium were compared with those obtained after a slight delay while patients repeatedly dry swallowed. When severe surface flow artifacts were present, the extent of mucosal disease was underestimated in all cases. Mild surface flow artifacts interfered with the demonstration of the reticular pattern of Barrett esophagus, and luminal flow artifacts caused misinterpretation. The demonstration of strictures was unaffected by flow artifacts. This study suggests that the dry swallowing maneuver and some delay improve depiction of esophageal surface details on double-contrast radiographs and obviate interpretive error from barium flow artifacts.  相似文献   
999.
Meijers  JC; Vlooswijk  RA; Kanters  DH; Hessing  M; Bouma  BN 《Blood》1988,72(4):1401-1403
Monoclonal antibodies specific for protein C inhibitor (PCI) partially blocked the inactivation of activated protein C (APC) in plasma, whereas in a purified system, the PCI activity could be completely blocked. The inactivation of APC in normal and in PCI-depleted plasma was similar in the absence of heparin. The addition of heparin did not change the rate of inactivation of APC in PCI-depleted plasma, whereas in normal plasma a rapid phase of inhibition of APC was followed by a slower phase of inhibition. The slower phase was identical to the rate of inhibition of APC in the absence of heparin. After incubation of normal plasma with a monoclonal antibody specific for PCI that blocked its activity, there was no difference in heparin-dependent or heparin- independent inhibition of APC. These results indicate that in the absence of heparin PCI is unable to inactivate APC in a plasma environment.  相似文献   
1000.
Chen  Z; Font  MP; Loiseau  P; Bories  JC; Degos  L; Lefranc  MP; Sigaux  F 《Blood》1988,72(2):776-783
The authors have analyzed the involvement of V gamma and J gamma segments in TRG gamma rearrangement from a series of 40 acute lymphoblastic leukemia (ALL), including 25 T- and 15 B-lineage cases, in which TRG gamma are rearranged. Sixty-five rearranged alleles were studied. The authors first describe the cloning and sequencing of two variable segments, V gamma 11 and psi V gamma 12, which rearrange in T- and B-neoplastic cells. To date three subgroups of translatable V gamma segments have been described. The authors show that V gamma 11 is the unique member of a new fourth V gamma subgroup that also rearranges in normal polyclonal T cells and that psi V gamma 12 is located at 5- kilobase (kb) downstream to V gamma 11. As shown by DNA sequence analysis, V gamma 11 shares a 60% homology with V gamma 10 (third subgroup) and a 50% homology with V gamma 9 (second subgroup) but no appreciable homology with the V gamma segments from the first family. In contrast to psi V gamma 12, V gamma 11 is translatable. In this paper the authors have also attempted to determine which V gamma segments were rearranged in the ALL cases by hybridization with a J gamma probe and genomic probes specific of the four subgroups. In the 54 instances in which the rearrangement was consistent with J gamma 1 or J gamma 2 involvement, the authors have identified the corresponding V gamma segments and have not found any other rearrangements suggestive of the existence of further V regions. The V gamma segments, belonging to the first subgroup, were the most frequently used (41 alleles). V gamma 9, V gamma 10, V gamma 11, and psi V gamma 12 were found rearranged in cases 3, 4, 5, and 1, respectively. No cases using the pseudo psi V gamma 1, psi V gamma 5, and psi V gamma 6 segments were found. Pseudo V gamma segments were not found rearranged in T cells, while V gamma 2 and V gamma 4, segments are frequently used. In contrast to the V gamma I gene rearrangement, the involvement of the V gamma II, V gamma III, and V gamma IV subgroups was most frequently observed in T-ALL with stage II differentiation (CD7+, CD4+, and/or CD8+, CD3-), than in those with stage I (CD7+, CD4-, CD8-, CD3-), than in those with stage I (CD7+, CD4-, CD8-, CD3-) and stage III (CD7+, CD4+/-CD8+/-CD3+).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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