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21.
The Authors, after a short introduction concerning the primary carcinoma of the cystic duct and the exact definition according to Farrar's criteria, report a case occurred to their observation, the 35th case of international literature. In particular the importance of some hemato-clinical parameters and instrumental investigation (ERCP, angio-CT) to underlined in order to surgical indication. In the case here reported cholecystectomy uses informed with partial resection of the hepato-choledochus and excision of some periductal and pericholedochus lymph nodes. Finally, the Authors discuss about clinical data and diagnostic and therapeutic trends, on the case of their experience and literature review.  相似文献   
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The total experience (154 patients) with ball-valve (Starr-Edwards) replacement of the tricuspid valve, alone and in combination, through Dec. 31, 1971, at the Mayo Clinic is reviewed. The early mortality rate with isolated tricuspid replacement was twice that for tricuspid replacement combined with replacement of other valves. Among patients receiving three valves, those with "functional' tricuspid insufficiency and those who were in New York Heart Association (N.Y.H.A.) Class IV preoperatively had a higher early mortality rate. The early mortality rate for the total group was 28%. Of those surviving tricuspid plus mitral valve replacement, 70% were alive at 3 years; at latest follow-up, 94% of those surviving were functionally improved. Of those surviving triple valve replacement, 56% were alive at 3 years; at latest follow-up, 93% of those surviving were functionally improved. Previous cardiac surgery with residual tricuspid valve dysfunction and severe disability, as judged by N.Y.H.A. class, influenced the outcome adversely. The experience reported here provides a standard against which never prostheses can be compared.  相似文献   
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Two hundred sixty-two patients with active upper gastrointestinal (GI) bleeding underwent panendoscopy between July 1970 and March 1973. There was 100% accuracy of endoscopic diagnosis as to the anatomical site of bleeding; the etiopathologic definition was 94.7% accurate. The series was divided into two groups, 116 with "liver disease" and 146 with "no liver disease." There were 107 patients with varices: 21 fell into no liver disease (small varices) and 86 into liver disease (39 small and 47 large varices). All had associated gastritis. Three endoscopic bleeding patterns were identified in the liver disease group. Only 27% of the patients in the liver disease group with varices (cirrhotics) had frank variceal hemorrhage, whereas 57% bled from hemorrhagic gastritis. The diagnostic unit provided early diagnosis, meaningful therapy, organized data gathering, and rough estimates of ultimate prognosis.  相似文献   
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BACKGROUND: Neuromyotonia (NMT) has been postulated to be an autoimmune channelopathy, probably by affecting voltage gated potassium channels (VGKC) leading to excitation and abnormal discharges [Sinha et al., Lancet 338 (1991) 75]. OBJECTIVE: To report three patients with NMT who had other associated immune-mediated conditions, i.e., myasthenia gravis, thymoma and various types of peripheral neuropathies. One patient had peripheral neuropathy and involvement of pre- and post-synaptic neuromuscular junction. RESULTS: All three patients had evidence of polyneuropathy and neuromyotonic discharges on electrodiagnostic studies. Elevated acetylcholine receptor antibodies were noted in all patients and malignant thymoma was found in two patients with metastasis. All three patients showed moderate to marked response to plasma exchange. CONCLUSIONS: These findings strongly suggest a humoral autoimmune pathogenesis of NMT, probably by K(+) channel involvement, affecting acetylcholine quantal release and postsynaptic membrane. Clinicians should be aware of this association of immune-mediated conditions in NMT patients and marked improvement with plasma exchange.  相似文献   
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Magnetic fields with quasi-symmetry are known to provide good confinement of charged particles and plasmas, but the extent to which quasi-symmetry can be achieved in practice has remained an open question. Recent work [M. Landreman and E. Paul, Phys. Rev. Lett. 128, 035001, 2022] reports the discovery of toroidal magnetic fields that are quasi-symmetric to orders-of-magnitude higher precision than previously known fields. We show that these fields can be accurately produced using electromagnetic coils of only moderate engineering complexity, that is, coils that have low curvature and that are sufficiently separated from each other. Our results demonstrate that these new quasi-symmetric fields are relevant for applications requiring the confinement of energetic charged particles for long time scales, such as nuclear fusion. The coils’ length plays an important role for how well the quasi-symmetric fields can be approximated. For the longest coil set considered and a mean field strength of 1 T, the departure from quasi-symmetry is of the order of Earth’s magnetic field. Additionally, we find that magnetic surfaces extend far outside the plasma boundary used by Landreman and Paul, providing confinement far from the core. Simulations confirm that the magnetic fields generated by the new coils confine particles with high kinetic energy substantially longer than previously known coil configurations. In particular, when scaled to a reactor, the best found configuration loses only 0.04% of energetic particles born at midradius when following guiding center trajectories for 200 ms.  相似文献   
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We present a case of visceral leishmaniasis confirmed after the histological investigation of an ulcerate lesion of the scalp in an HIV-1-infected patient receiving highly active antiretroviral therapy (HAART). Histological examination of the skin lesion revealed a squamous cell carcinoma superinfected by amastigotes of Leishmania infantum from the bloodstream. Because HIV-1-infected individuals can harbour parasitic infections in normal and neoplastic tissue, it is necessary to examine carefully any skin lesions, particularly those with uncommon aspects or a worsening course, to exclude superinfections by unsuspected pathogens.  相似文献   
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The young, active patient with a meniscal tear poses a significant challenge for the surgeon. Multiple factors influence the treatment of meniscal pathology and the ultimate goal of meniscal surgery should be to remove only torn and nonfunctional tissue by limited meniscectomy or to repair amenable tears. The chondroprotective significance of the meniscus has influenced the current treatment of meniscal injuries in young athletes with the emphasis on repairing meniscus tears to include complex tears and tears in the avascular zone. Partial meniscectomy and meniscal repair techniques have provided good long-term clinical success and return to activity. The decision to debride versus repair a meniscus depends on tear pattern, location, and the patient's willingness to comply with postoperative restrictions. In patients with symptomatic meniscus deficiency, meniscal allograft transplant is an option that may provide pain relief but may not allow return to sports. The purpose of this article is to provide a succinct review of the diagnostic and management principles for the young, active patient with a meniscal tear.  相似文献   
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