7,644 research outputs found
Gastrointestinal complications of hepatic transplantation
In this series of 150 orthotopic hepatic transplants, clinically significant gastrointestinal hemorrhage occurred in 34 patients (23%). Five patients (15%) survived this complication. Enteric perforations occurred in 20 patients following 198 biliary-enteric procedures. Only one patient survived. Enteric perforations unrelated to biliary procedures fared only slightly better with one survivor among eight perforations. These results clearly do not warrant complacency. Modifications advocated are an aggressive diagnostic approach and early reoperation with establishment of extensive peritoneal drainage where necessary
Liver Resection for Hepatic Adenoma
Between 1970 and 1978, eight hepatic adenomas were resected. Four of the eight patients took oral contraceptive pills before the hepatic adenoma was identified; one patient was male. Four patients had evidence of bleeding at the time of presentation. The original histologic diagnosis in the first five patients was malignant hepatoma. There has been no known recurrence of tumor and all patients are well. The use of oral contraceptives in these patients has been prohibited. Formal anatomic resection is recommended for hepatic adenoma when this procedure can be done without mortality or serious morbidity; however, in the future, less drastic treatments, such as occlusion of the hepatic arterial circulation to the tumor or discontinuation of oral contraceptives, may prove as effective as tumor resection. © 1979, American Medical Association. All rights reserved
Kidney transplantation. Modern trends in kidney transplantation.
Trends in renal transplantation stem from recognition of the virtues and drawbacks of this kind of treatment and from a better appreciation of the interrelationship between transplantation and dialysis
0- quantum transition in a carbon nanotube Josephson junction: universal phase dependence and orbital degeneracy
We investigate experimentally the supercurrent in a clean carbon nanotube
quantum dot, close to orbital degeneracy, connected to superconducting leads in
a regime of strong competition between local electronic correlations and
superconducting proximity effect. For an odd occupancy of the dot and
intermediate coupling to the reservoir, the Kondo effect can develop in the
normal state and screen the local magnetic moment of the dot. This leads to
singlet-doublet transitions that strongly affect the Josephson effect in a
single-level quantum dot: the sign of the supercurrent changes from positive to
negative (0 to -junction). In the regime of strongest competition between
the Kondo effect and proximity effect, meaning that the Kondo temperature
equals the superconducting gap, the magnetic state of the dot undergoes a first
order quantum transition induced by the superconducting phase difference across
the junction. This is revealed experimentally by anharmonic current-phase
relations. In addition, the very specific electronic configuration of clean
carbon nanotubes, with two nearly orbitally degenerated states, leads to
different physics depending whether only one or both quasi-degenerate upper
levels of the dots participate to transport, which is determined by their
occupancy and relative widths. When the transport of Cooper pairs takes place
through only one of these levels, we find that the phase diagram of the
phase-dependent 0- transition is a universal characteristic of a
discontinuous level-crossing quantum transition at zero temperature. In the
case were two levels participate to transport, the nanotube Josephson current
exhibits a continuous 0- transition, independent of the superconducting
phase, revealing a different physical mechanism of the transition.Comment: 14 pages, 12 figure
An Optical Study of Two VY Sculptoris-Type Cataclysmic Binary Stars: V704 And and RX J2338+431
We report observations of the known cataclysmic variable star (CV) V704 And,
and also confirm that the optical counterpart of the ROSAT Galactic Plane
Survey source RX J2338+431 is a heretofore-neglected CV. Photometric and
spectroscopic observations from MDM Observatory show both systems to be
novalike variables that exhibit dips of 4-5 magnitudes from their mean
brightnesses, establishing them as members of the VY~Scl subclass. From
high-state emission-line radial velocities, we determine orbital periods of
0.151424(3) d (3.63 hr) for V704 And and 0.130400(1) d (3.13 hr) for RX
J2338+431. In V704 And, we find that the H-alpha emission-line measures cluster
into distinct regions on a plot of equivalent width versus full width at
half-maximum, which evidently correspond to high, intermediate, and low
photometric states. This allows us to assign spectra to photometric states when
contemporaneous photometry is not available, an apparently novel method that
may be useful in studies of other novalikes. Our low-state spectra of RX
J2338+431 show features of an M-type secondary star, from which we estimate a
distance of 890 +- 200 pc, in good agreement with the Gaia DR2 parallax.Comment: Accepted for Astronomical Journa
Manipulating the magnetic state of a carbon nanotube Josephson junction using the superconducting phase
The magnetic state of a quantum dot attached to superconducting leads is
experimentally shown to be controlled by the superconducting phase difference
across the dot. This is done by probing the relation between the Josephson
current and the superconducting phase difference of a carbon nanotube junction
whose Kondo energy and superconducting gap are of comparable size. It exhibits
distinctively anharmonic behavior, revealing a phase mediated singlet to
doublet transition. We obtain an excellent quantitative agreement with
numerically exact quantum Monte Carlo calculations. This provides strong
support that we indeed observed the finite temperature signatures of the phase
controlled zero temperature level-crossing transition originating from strong
local electronic correlations.Comment: 5 pages, 4 figures + supp. material
Thoracic duct drainage in organ transplantation: Will it permit better immunosuppression?
It is possible that thoracic-duct drainage, a major but neglected immunosuppressive adjunct, can have an important impact on organ transplantation. If thoracic-duct drainage is started at the time of transplantation, the practicality of its use in cadaveric cases is greatly enhanced. With kidney transplantation, the penalty of not having pretreatment for the first organ is compensanted by the automatic presence of pretreatment if rejection is not controlled and retransplantation becomes necessary. The advantage of adding thoracic-duct drainage to conventional immunosuppression may greatly enhance the expectations for the transplantation of extrarenal organs, such as the liver, pancreas, heart, and lung. There is evidence that pretreatment with thoracic-duct drainage of patients with cytotoxic antibodies may permit successful renal transplantation under these otherwise essentially hopeless conditions. Exploration of the neglected but potentially valuable tool of thoracic-duct drainage seems to the authors to be highly justified in other centers
Liver Transplantation for Budd-Chiari Syndrome
Orthotopic liver transplantation was accomplished in a 22-year-old woman dying of the Budd-Chiari syndrome. She is well and has normal liver function 16 months postoperatively. In view of the good early result, it will be appropriate to consider liver replacement for this disease in further well-selected cases. © 1976, American Medical Association. All rights reserved
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