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41.
42.
Brian Hung-Hin Lang Diane T. Y. Chan Felix Che-Lok Chow Kai Pun Wong Rita Y. K. Chang 《World journal of surgery》2016,40(7):1611-1617
Background
It remains uncertain whether a parathyroid gland (PG) that appears darkened or severely bruised but still has an attached vascular pedicle should be left in situ or taken out and auto-transplanted following total thyroidectomy. Our study aimed to examine the impact of discolored PGs (DPGs) on short- and long-term hypoparathyroidism.Methods
One hundred and three patients who underwent total thyroidectomy with 4 clearly identified PGs were analyzed. Location (superior/inferior) and color of each PG were recorded. Patients without DPG were grouped into I while those with 1–2 DPGs and ≥3 DPGs were grouped into II and III, respectively. Transient hypoparathyroidism meant adjusted Ca <2.00 mol/L 24 h after surgery and/or need for supplements. Protracted hypoparathyroidism meant a subnormal PTH at 4–6 weeks and/or supplements >6 weeks. Permanent hypoparathyroidism meant supplements ≥1 year.Results
Relative to I, group III had greater adjusted Ca drop at postoperative 1-h (p = 0.012), 24-h (p < 0.001) and lower day-1 PTH (p = 0.015). Having ≥3 DPGs (OR 14.00, 95 % CI 1.575–124.474, p = 0.018) was an independent factor of transient hypoparathyroidism. However, permanent hypoparathyroidism rate was higher than in group I than II (p = 0.019). Eight patients (25.8 %) in group I had undetectable day-1 PTH, while none in group III had undetectable day-1 PTH. Graves’ disease/toxic goiter (OR 15.166, 95 % CI 2.594–88.661, p = 0.003) and excised gland weight (OR 1.028, 95 % CI 1.010–1.046, p = 0.003) were independent factors of ≥3 DPGs.Conclusions
PG discoloration is associated with transient hypoparathyroidism while normal colored PG with seemingly adequate blood supply does not always imply functionally normal gland. These findings highlights the need for a real-time intraoperative method to assess PG viability.43.
Clozapine blocks D-amphetamine-induced excitation of dopamine neurons in the ventral tegmental area.
Wei-Xing Shi Xiang-Yang Zhang Chen-Lun Pun Benjamin S Bunney 《Neuropsychopharmacology》2007,32(9):1922-1928
Current antipsychotic drugs are thought to inhibit central dopamine (DA) transmission by blocking DA receptors. Here, we provide evidence that the atypical antipsychotic drug clozapine may produce part of its effect by inhibiting a subset of excitatory inputs to DA neurons. Thus, in chloral hydrate-anesthetized rats, systemic administration of D-amphetamine produced two opposing effects on DA neurons in the ventral tegmental area. Under control conditions, D-amphetamine inhibited the firing of the cell through D2-like receptors. When D2-like receptors were blocked by raclopride, D-amphetamine excited DA neurons, instead of producing no effect. The excitation, expressed as an increase in firing rate and a slow oscillation in firing pattern, was suppressed by the adrenergic alpha1 receptor antagonist prazosin, suggesting an involvement of alpha1 receptors. In rats pretreated with the typical antipsychotic drug haloperidol, D-amphetamine also excited DA neurons. However, when given after clozapine, D-amphetamine produced no significant effects. The failure of D-amphetamine to produce an excitation is not due to an incomplete blockade of D2-like receptors by clozapine because co-treatment with clozapine and raclopride also failed to enable the excitatory effect of D-amphetamine. The suggestion that clozapine inhibits the excitatory effect of D-amphetamine is further supported by the finding that clozapine, given after D-amphetamine, reliably reversed D-amphetamine-induced excitation in raclopride-treated rats. Thus, different from raclopride and haloperidol, clozapine may inhibit DA transmission through two additive mechanisms: blockade of DA receptors and inhibition of an amphetamine-sensitive, excitatory pathway that innervates DA neurons. 相似文献
44.
Cyanosis, clubbing, and arterial oxygen desaturation may occur in patients with liver disease, and are attributed to the presence of pulmonary or peripheral arterio-venous shunting. Cardiac catheterisation and angiocardiography in a patient with a normal heart did not demonstrate the presence of abnormal arterio-venous anastomoses. Pulmonary shunting was proved when intravenous technetium-labelled macroaggregated albumin, normally held up in capillary networks, was passed quickly through the lungs and immediately detected in high systemic blood flow organs. The opening of peripheral and pulmonary anastomoses in patients with liver disease may be owing to the presence of a vasodilatory substance such as ferritin, which was found to be abnormally increased in the patient's blood. 相似文献
45.
Haas MJ Reinacher D Pun K Wong NC Mooradian AD 《Metabolism: clinical and experimental》2000,49(12):1572-1578
Apolipoprotein AI (apoAI) expression is inversely related to the incidence of atherosclerosis. ApoAI expression is also influenced by the nutritional state and diabetes. We used both cell culture and animal models to examine the effect of fasting and ketoacidosis on apoAI gene expression. Two days of food deprivation in rats increased hepatic and intestinal apoAI mRNA by 2.6- and 2.3-fold, respectively (P < .05). The absolute concentration of plasma apoAI did not change. However, the plasma apoAI concentration relative to the plasma concentration of serum proteins was increased 23% (P < .05). In fasting rats, there was a significant positive correlation between the serum beta-hydroxybutyrate concentration and hepatic or intestinal apoAI mRNA level. Despite this correlation, changes in apoAI mRNA are probably not mediated by ketone bodies, since neither hepatic nor intestinal apoAI mRNA levels were altered in rats maintained on a ketogenic diet for 10 days or treated with isobutyramide, an orally active ketone analog. In addition, the activity of the rat apoAI promoter was not altered in Hep G2 cells treated with isobutyramide or fatty acids or exposed to hypoglycemic conditions, while dexamethasone increased promoter activity 1.9-fold (P < .05). These data indicate that metabolic changes other than ketone bodies, such as an increase in plasma glucocorticoids, may account for starvation-induced expression of apoAI. 相似文献
46.
Thirty-five patients with sequential fractures of both hips were studied prospectively. The second hip fractures occurred more commonly if the patients were institutionalized, if they suffered from concomitant neurologic diseases such as previous stroke or Parkinsonism, or if there was biochemical evidence of osteomalacia. Twelve patients sustained the contralateral hip fracture within 12 months of the first one. There was a significant correlation between biochemical evidence of osteomalacia and early occurrence of the second hip fracture. Although rehabilitation was difficult for such patients, it was possible with a longer period of intensive physiotherapy; only three patients were not able to walk upon discharge from the hospital after the second hip fracture. 相似文献
47.
Cyclosporin A is associated with faster engraftment and less mucositis than methotrexate after allogeneic bone marrow transplantation 总被引:1,自引:0,他引:1
K. Atkinson J. C. Biggs A. Ting A. J. Concannon A. J. Dodds A. Pun 《British journal of haematology》1983,53(2):265-270
S ummary . Thirty-eight patients with severe aplastic anaemia or acute leukaemia received HLA-identical sibling marrow transplants. Seventeen were treated with methotrexate and 21 with cyclosporin A (CyA) to minimize graft-versus-host disease post transplant. Marrow engraftment was more rapid and oropharyngeal mucositis less severe in those receiving CyA. This resulted in a shorter period of neutropenia and thrombocytopenia, fewer platelet and granulocyte transfusions and less fever. These benefits have to be weighed against the increased nephrotoxicity of CyA. 相似文献
48.
Parathyroid adenomas evaluated by Tl-201/Tc-99m pertechnetate subtraction scintigraphy and high-resolution ultrasonography 总被引:2,自引:0,他引:2
Winzelberg GG; Hydovitz JD; O'Hara KR; Anderson KM; Turbiner E; Danowski TS; Lippe RD; Melada GA; Harrison AM 《Radiology》1985,155(1):231-235
Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar. 相似文献
49.
R Y Pun K C Marshall W J Hendelman P B Guthrie P G Nelson 《The Journal of neuroscience》1985,5(1):181-191
Locus coeruleus (LC) explants were co-cultured with dissociated spinal neurons of mice. Nerve fibers exhibiting catecholamine fluorescence radiated from the explants and frequently invested spinal cord (SC) neurons close to the explants. Electrical stimulation of the explant and iontophoretic application of norepinephrine evoked a spectrum of slow depolarizing, hyperpolarizing, and biphasic responses in the SC cells. The responses to LC stimulation and to application of norepinephrine were usually similar in a given cell. The depolarizing responses were associated with an increase in apparent input resistance and pharmacologic tests indicated that the responses were mediated by alpha-receptors. Neurons in regions innervated by catecholamine-containing fibers usually gave depolarizing responses to LC stimulation and such neurons had a very high probability of exhibiting depolarizing responses to applied norepinephrine. It would appear that either locus coeruleus explants favored the survival of cells with alpha-receptors or expression of these receptors in SC neurons was induced by innervation of the neurons by locus coeruleus axons. 相似文献
50.
This educational intervention was designed as part of a garment worker occupational health and safety initiative, with the goal to reduce musculoskeletal symptoms in this monolingual Cantonese speaking population. Using risk communication and the Chinese concepts of yin and yang, the class curriculum was designed to be participatory. It focused on linking symptoms to high risk work activities; explaining the nature of musculoskeletal injury; and encouraging compliance with self care measures of ice, stretching, and early symptom reporting. A total of 21 women completed the Healthy Work Classes, with an increase in perceived levels of energy measured after each class. Additionally, contingency contracting for both individual and workplace change was piloted. This curriculum was revised to become a "train the trainer" program, with training of garment worker leaders and the goal to disseminate this prevention based curriculum to garment workers in the Oakland, California community. 相似文献