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81.
Kidneys from donation after circulatory death (DCD) donors are utilized variably worldwide, in part due to high rates of delayed graft function (DGF) and putative associations with adverse longer-term outcomes. We aimed to determine whether the presence of DGF and its duration were associated with poor longer-term outcomes after kidney transplantation from DCD donors. Using the UK transplant registry, we identified 4714 kidney-only transplants from controlled DCD donors to adult recipients between 2006 and 2016; 2832 recipients (60·1%) had immediate graft function and 1882 (39·9%) had DGF. Of the 1847 recipients with DGF duration recorded, 926 (50·1%) had DGF < 7 days, 576 (31·2%) had DGF 7–14 days, and 345 (18·7%) had DGF >14 days. After risk adjustment, the presence of DGF was not associated with inferior long-term graft or patient survivals. However, DGF duration of >14 days was associated with an increased risk of death-censored graft failure (hazard ratio 1·7, p = ·001) and recipient death (hazard ratio 1·8, p < ·001) compared to grafts with immediate function. This study suggests that shorter periods of DGF have no adverse influence on graft or patient survival after DCD donor kidney transplantation and that DGF >14 days is a novel early biomarker for significantly worse longer-term outcomes.  相似文献   
82.
Background:To evaluate the changes in penile sensation by electrophysiological tests in patients who underwent radical prostatectomy (RP) and to demonstrate the role of dorsal penile nerve injury in postoperative erectile dysfunction.Materials and methods:Twenty-six volunteer patients who were eligible for RP were included in the study. Preoperative penile sensory electromyography and the International Index of Erectile Function-5 (IIEF-5) questionnaire were done for each patient. Erectile function assessment and electrophysiological evaluation of penile sensation were repeated at postoperative 3rd and 6th months.Results:Postoperative IIEF-5 scores and electromyography values were significantly lower than preoperative findings (p < 0.05). The IIEF-5 scores in the nerve sparing-RP (NS-RP) group were significantly higher than the non-nerve sparing-RP (NNS-RP) group in the postoperative period. Nerve conduction velocity values in the NS-RP group were also higher than the NNS-RP group at the postoperative 3rd and 6th months. However, these changes were not statistically significant (p > 0.05).Conclusions:Patients who underwent RP have decreased penile sensation due to cavernous nerve damage and a possible dorsal penile nerve injury. The decrease of penile sensation may be associated with postoperative erectile dysfunction.  相似文献   
83.
Immunological factors are important in the pathogenesis of a wide spectrum of hepatobiliary diseases. Using flow cytometry, we determined the changes in lymphocyte subsets and natural killer cells in 123 individuals (81 patients with liver disease and 42 healthy volunteers). The liver diseases included periportal fibrosis (PPF, 10 patients), liver cirrhosis (LC, 31 patients), and hepatocellular carcinoma (HCC, 40 patients). Schistosomiasis and viral hepatitis B and C were the putative etiological agents of liver diseases. Immunophenotyping by indirect immunofluorescence was conducted using monoclonal antibodies to CD3 (T-lymphocytes), CD4 (helper/inducer T-cells), CD8 (suppressor/cytotoxic T-cells), and CD57 (natural killer cells) cell surface markers. Immunophenotyping of PPF patients showed no significant changes in all markers compared with the healthy controls. However, there was a significant decrease ( P<0.01) in CD3 and CD4 T-cells, and a highly significant increase ( P<0.001) in CD57 T-cells in patients with LC or HCC. In addition, LC and HCC patients showed no significant change in CD8 T-cells compared with controls. In conclusion, the progression of liver diseases is associated with a dysregulation of cellular immune responses. T-lymphocytes and natural killer cells may play a role in the immunopathogenesis of liver cirrhosis and HCC.  相似文献   
84.
Reaction of propane-1,3-sultone with amines gave N-substituted aminosulphonic acids2a?i. Dehydration of2a?c with POCl3 gave the corresponding sultams3a?c. Propane-1,3-sultone1 reacted with tertury amines to give the betaiene salts4–11. 2,4-Dimethyl-1,3-butadiene-1,4-sultone12 condensed with amines to give N-substituted-2,4-dimethyl-1,3-butadiene-1,4-sultams13a and13b. The reaction of3a, 13a with hydrazine hydrate gave acid hydrazides3d or13c. Compounds3d, 13c reacted with isocyanates to yield urea derivatives14a?c, 15a?c.  相似文献   
85.
The authors have previously described an extradural transmaxillary approach to the anterior compartment of the cavernous sinus. In an effort to expand the surgical access to that area without necessitating a craniotomy or wide transfacial dissection, they present a modification of the transmaxillary approach to the sellar region and cavernous sinus. Methods: The approach was developed on 12 fresh and 12 embalmed cadaveric specimen, and 2 dry skulls. The initial sublabial incision is followed by a maxillotomy to expose the course of the infraorbital nerve (terminal branch of maxillary branch of the trigeminal nerve) on the roof of the maxillary sinus. The route of the infraorbital nerve is traced to the pterygopalatine fossa as a guide to the foramen rotundum. Superomedial drilling of the foramen rotundum is then performed to reveal the contents of the superior orbital fissure. After the nerves are safely identified in the superior orbital fissure, medial enlargement of the window into the cavernous sinus is made possible by drilling the lateral and posterior wall and septum of the sphenoid sinus. Results: The combined transmaxillary transsphenoidal approach offers an excellent exposure of the sellar and infrasellar region. The approach offers clear visualization of the ipsilateral loop of the carotid artery, the pituitary fossa, and the cranial nerves of the ipsilateral cavernous sinus. Mean operative reach is 38 mm from the posterior wall of the maxillary sinus to the ipsilateral carotid loop and 56 mm to the contralateral loop. The width of the operative window is 26 mm at the base within the cavernous sinus. Conclusion: The model offers a minimally invasive approach that avoids the need for craniotomy or violating the nasal cavity. It may be safely employed to access vascular as well as invasive lesions of the sellar and infrasellar region. The approach offers excellent visualization of the ipsilateral intracavernous carotid artery with both proximal and distal control, as well as cranial nerves III, IV, VI, V2, the hypophyseal region, and the medial aspect of the contralateral cavernous sinus.  相似文献   
86.
Summary Bone changes in sickle cell disease occur due to marrow hyperplasia, tissue ischaemia and infarction due to vaso-occlusion. Between 1982 and 1991 thirty four patients were treated in the Orthopaedic and Neurosurgery Departments of the Kind Fahd University Hospital, Al-Khobar, with spinal complications due to sickle cell disease. There were 21 males and 13 females aged between 4 and 28 years (mean 17.4 years). Structural changes in the vertebral bodies due to marrow hyperplasia occurred in 44% of the patients. Avascular necrosis leading to collapse of the vertebral bodies was seen in 9 (27%) patients. Infective spondylitis was the most serious complication seen in 8 (24%) patients; the majority needed anterolateral decompression and bone grafting. The spine is often affected in sickle cell disease and aggressive treatment with close follow-up is required to avoid disabling complications.
Résumé Les modifications osseuses survenant au cours de la drépanocytose sont la conséquence d'une hyperplasie médullaire, d'une ischémie tissulaire et d'un infarcissement liés à l'occlusion vasculaire. Cette étude rétrospective analyse les complications rachidiennes de la drépanocytose observées de 1982 à 1991. Trente-quatre patients ont été traités dans les services d'orthopédie et de neuro-chirurgie de l'Hôpital universitaire King Fahd à Al Khobar. Il s'agissait de 21 hommes et de 13 femmes, âes en moyenne de 17.4 ans, avec des extrêmes de 4 à 28 ans. Des modifications structurales du corps vertébral liées à l'hyperplasie médullaire sont survenues chez 44% des patients. Des nécroses avasculaires responsables d'un effondrement du corps vertébral ont été observéees chez 9 patients (26.5%). La spondylite infectieuse, qui constitue la complication la plus grave, a concerné 8 patients (23.5%), dont la plupart ont bénéficié d'une décompression antérolatérale et de greffes osseuses. Nous pensons que le rachis est souvent atteint au cours de la drépanocytose et qu'un traitement agressif et une étroite surveillance sont nécessaires pour éviter des séquelles majeures.
  相似文献   
87.
OBJECTIVE--To investigate changes in the electrocardiographic QT interval during rapidly induced, sustained hypocalcaemia in healthy volunteers. DESIGN--Serial rate corrected QT measurements were made during and after a variable rate trisodium citrate infusion designed to "clamp" the whole blood ionised calcium concentration 0.20 mmol/l below baseline for 120 min. SUBJECTS--12 healthy teetotallers aged 19- 36 years who were not receiving medication known to influence calcium homoeostasis. MAIN OUTCOME MEASURES--Whole blood ionised calcium concentration and QaTc intervals (onset of the Q wave to T wave apex divided by the square root of the RR interval). RESULTS--Mean (SD) ionised calcium concentration decreased from 1.18 (0.03) mmol/l preinfusion to values close to target (0.98 mmol/l) between 10 and 120 min. The QaTc interval lengthened from a baseline of 0.309 (0.021) to a maximum 0.343 (0.024) s0.5 at 10 min before returning to a stable level from 15 to 120 min (0.334 (0.023) and 0.330 (0.023) s0.5 respectively). The change from baseline of both variables expressed as a ratio (delta QaTc/ delta [Ca2+]) was greater during rapid induction of hypocalcaemia (at 5 and 10 min) than at other times during and after the infusion (P < 0.02). CONCLUSIONS--The disproportionate prolongation of QaTc interval during prompt induction of hypocalcaemia suggests rate dependency which can be represented by a hysteresis relation between (ionised calcium, QaTc) coordinates. This finding may have clinical implications.  相似文献   
88.
BACKGROUND: Plant fats and oils are major sources of mono- and polyunsaturated fatty acids as well as vitamin E, the major fat-soluble antioxidants in human nutrition. Dietary antioxidants are expected to reduce cancer risk by minimizing DNA damage. AIM OF THE STUDY: To compare the effects of gamma-tocopherol rich corn oil and the mixture of the alpha-tocopherol rich olive/sunflower oil on plasma concentration of tocopherols and on the frequency of sister chromatid exchange (SCE), an indicator of DNA damage. METHODS: This study had a double-blind, cross-over design and was conducted in 20 normal healthy non-smoking males aged 19-31 years. Design included a 2-week adjustment period and two 2-week test periods in which diets containing 30% energy as fat including either 80 g of corn oil (CO) (20 mg alpha-tocopherol, 100 mg gamma-tocopherol) or 80 g of olive/ sunflower oil (OSO) (24 mg alpha-tocopherol, 2.4 mg gamma-tocopherol), as the main fat-source, were given. Blood samples for analysis of SCE rate and content of tocopherols were collected at the beginning (T0), after adjustment (T1) and after the test period (T2) in intervals of 2 weeks. RESULTS: After two weeks of the corn oil diet, the plasma concentration of gamma-tocopherol increased but alpha-tocopherol decreased significantly compared to the olive/sunflower oil diet. The concentration of alpha-tocopherol increased (CO: 22.99 +/- 1.11 vs. OSO: 24.40 +/- 1.49 micromol/l) and that of gamma-tocopherol decreased (CO: 4.19 +/- 0.29 vs. OSO: 2.99 +/- 0.25 micromol/l) after the olive/sunflower oil diet. Intake of the corn oil diet was associated with reduced SCE rate and intensity, whereas there was no change in SCE after the olive/sunflower oil diet (CO: 7.66 +/- 0.25 vs. OSO: 8.06 +/- 0.47 mean SCE/cell) CONCLUSIONS: The combination of gamma-tocopherol with alpha-tocopherol in corn oil diet despite the lower alpha-tocopherol equivalents/diene acid equivalents ratio achieved better protection against DNA damage than alpha-tocopherol alone in the olive/sunflower oil diet.  相似文献   
89.
Imaging of septate gallbladder   总被引:1,自引:0,他引:1  
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90.
High-frequency ultrasound (US) is an efficient, rapid and inexpensive altenative to magnetic resonance imaging (MRI) for investigation of diseases in the soft tissues of the wrist and hand. US allows detection of foreign bodies and the reliable identification of a variety of traumatic lesions affecting tendons, annular pulleys, ligaments, vessels and nerves. Inflammatory diseases of tendons, including acute and chronic tenosynovitis and some degenerative conditions in the wrist and hand, can also be diagnosed. In entrapment neuropathies, US is able to identify nerve shape changes and possible extrinsic space-occupying lesions that may cause nerve compression within the tunnels. In patients with localized swelling of the hand or wrist, US is able to assess the presence of an expansile lesion and to characterize its nature in most cases. The objective of this article is to review the main findings and the primary indications of US in the investigation of disorders of the hand and wrist. Received: 10 September 1998 Accepted: 24 November 1998  相似文献   
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