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81.
82.
OBJECTIVE AND IMPORTANCE: Parathyroid carcinoma is a rare entity, and fewer than 200 cases have been described. It is a slowly progressive disease characterized by frequent recurrences and local metastases. Most patients with parathyroid carcinoma die from metabolic complications of hyperparathyroidism. Five-year survival rates range from 25 to 50%. Functional parathyroid carcinoma is a rare cause of hyperparathyroidism that affects only 0.32 to 5% of all patients who undergo surgery for hypercalcemia. A review of the literature revealed only one other reported case of metastatic intracranial parathyroid carcinoma, in a patient who experienced local recurrence and metastatic disease when she was diagnosed with an intracranial lesion. CLINICAL PRESENTATION: We report the case of a 44-year-old African-American man with recent-onset, right lower-extremity weakness and hypercalcemia 4 years after he underwent a parathyroidectomy for parathyroid carcinoma. At presentation, his parathyroid level was 467 pg/ml, and his serum calcium level was 15.2 mg/dl. Imaging studies revealed an isolated enhancing left mesial frontoparietal mass. A systemic Cardiolite study demonstrated a single focus of radiotracer uptake in this region. No abnormal uptake was demonstrated in the neck or elsewhere. INTERVENTION: The patient underwent a frameless stereotactic interventional magnetic resonance imaging-guided resection via a parasagittal interhemispheric approach. Pathological findings were consistent with parathyroid carcinoma. After resection, his right lower-extremity weakness and secondary hyperparathyroidism resolved. CONCLUSION: The typical natural history of parathyroid carcinoma concludes with death from complications of hyperparathyroidism. This case report supports aggressive surgical management to eliminate all parathyroid hormone-secreting malignant tissue and prevent metabolic complications. In this patient, intraoperative magnetic resonance imaging was helpful to ensure complete resection. 相似文献
83.
BACKGROUND/AIMS: We describe the histological patterns of rejection in liver transplant recipients using induction therapies with cyclosporine and tacrolimus monotherapy compared with standard triple therapy as historical control. METHODS: Patients formed part of the initial cohort in an open-labelled, randomised pilot study and were selected consecutively if they had histological rejection and no other confounding diagnoses. There were 13 patients in the cyclosporine monotherapy group (CsA), 11 in the tacrolimus monotherapy group and 13 in the triple therapy group (CAP). The histology of liver biopsies was reassessed blindly and the severity of rejection was recorded. RESULTS: The total Royal Free Hospital (RFH) rejection scores as well as other histological features (zone 3 haemorrhage, apoptosis in zones 1 and 3, steatosis, cholestasis, nuclear vacuolation, lymphoblasts and ballooning) were comparable in the three groups. There was no difference in individual components of the histological features comprising the diagnosis of rejection, except that the portal inflammation score was significantly lower in the tacrolimus group when compared with the CsA group (p=0.04). There was no significant difference in the number of patients with moderate/severe rejection between the three groups. Overall, there was no significant increase in histological severity of rejection in the monotherapy groups. CONCLUSIONS: The results suggest that the monotherapy may be as effective as the triple therapy in the initial post-transplant phase and that no particular graft histological changes were associated with the type of treatment. 相似文献
84.
OBJECTIVE: To determine whether differences existed in mood and coping styles among fertile men, oligoasthenospermic men, or euspermic men whose wives were undergoing ovulation stimulation with clomiphene and IUI. DESIGN: A cross-sectional research design. SETTING: Hospital-based academic fertility clinic. PATIENT(S): 30 fertile men with currently pregnant wives, 30 euspermic and 30 oligoasthenospermic men in couples undergoing ovulation stimulation with clomiphene and IUI. INTERVENTION(S): Measures of psychological well-being and coping were administered. MAIN OUTCOME MEASURE(S): Biodemographic information, and psychometric measures of mood and coping. RESULT(S): There were no significant differences among the groups on any of the measures except the Family Inventory of Life Events (FILE), in which fertile men reported higher stress levels. FILE scores in all groups were moderate, indicating typical levels of family stress. CONCLUSION(S): Mood and coping in the three groups were similar. This study suggests that men's psychological adjustment to their own infertility and to unexplained infertility is generally healthy. 相似文献
85.
Core promoter mutations and genotypes in relation to viral replication and liver damage in East Asian hepatitis B virus carriers 总被引:62,自引:0,他引:62
Lindh M Hannoun C Dhillon AP Norkrans G Horal P 《The Journal of infectious diseases》1999,179(4):775-782
Virus load and liver damage, as measured by quantitative polymerase chain reaction and histology activity index, were related to genotype and core promoter mutations in 43 chronic hepatitis B virus (HBV) carriers of East Asian origin. T-1762 mutants were more frequent in genotype C strains and were associated with more inflammation (P=.0036) and fibrosis (P=.0088) of the liver but not with hepatitis B e antigen (HBeAg) status or virus load. Conversely, precore mutations were associated with less liver inflammation (P=. 08), which was linked to HBeAg negativity and lower viral replication. Carriers with genotype C were more often HBeAg positive (P=.03) with precore wild type strains and more-severe liver inflammation (P=.009) than were those with genotype B. These findings suggest that pathogenic differences between genotypes may exist and that the T-1762 mutation may be useful as a marker for progressive liver damage but seem to contradict that down-regulation of HBeAg production is the major effect of this mutation. 相似文献
86.
Anthony A Pounder RE Dhillon AP Wakefield AJ 《Alimentary pharmacology & therapeutics》2000,14(2):241-245
BACKGROUND: Both Crohn's disease ileal ulcers and indomethacin-induced jejunal ulcers in the rat have a predilection for the mesenteric margin of the bowel wall. Unlike the anti-mesenteric margin, the mesenteric margin is supplied by small end-arteries that might render it more sensitive to ischaemic injury. AIM: To examine, in both situations, the histological relationship between the precise localization of small bowel ulcers and the mesenteric margin. METHODS: Ileal Crohn's disease ulcers identified in surgical resection specimens (n=5) and indomethacin-induced lesions in the rat jejunum (n=6) were examined macroscopically and histologically. RESULTS: In both the human ileum and the rat jejunum, ulcers occurred consistently along the mesenteric margin, with the most extensive mucosal injury occurring at two adjacent sites on either side of the midline of this margin. At these two sites, feeding arteries entered the muscularis propria. CONCLUSIONS: For anatomical reasons apparently related to the vasculature of the human and rodent small bowel, specific sites along the mesenteric margin are susceptible to Crohn's disease ulceration and NSAID damage, respectively. 相似文献
87.
Anthony A Sim R Guillaume JL Strosberg AD Dhillon AP Pounder RE Wakefield AJ 《Alimentary pharmacology & therapeutics》2000,14(5):579-585
BACKGROUND: We previously localized beta3-adrenergic receptors immunohistochemically in human gastrointestinal smooth muscle and incidently found a population of human pancreatic islet cells and duodenal epithelial neuroendocrine cells that also expressed beta3-adrenergic receptors. AIM: To identify the nature of the islet and duodenal cells that stained positive for beta3-adrenergic receptors. METHODS: Paraffin sections of human pancreas and duodenum and Chinese hamster ovary cells transfected with the human beta3-adrenergic receptor were immuno-stained for beta3-adrenergic receptors using an affinity-purified rabbit polyclonal antibody (anti-P12) raised against a 15 amino acid sequence (P12) of the human receptor. Immunohistochemical staining for the receptor was carried out in the presence and absence of P12 peptide and both somatostatin 14 and 18 peptides. beta3-adrenergic receptor-stained sections were also double-immunostained with anti-insulin, -glucagon, -somatostatin and -pancreatic polypeptide antibodies. RESULTS: A subpopulation of human pancreatic islet cells and duodenal epithelial cells expressed positive cytoplasmic beta3-adrenergic receptor immunostaining. Using distribution and double-staining techniques, these cells were found to be somatostatin-positive D cells but not A or B cells. The positive staining of D cells with anti-P12 antibody was inhibited by prior incubation of the antibody with P12 peptide but not somatostatin-14 or -28 peptides. Pancreatic vascular smooth muscle and duodenal vascular and non-vascular smooth muscle also stained with anti-P12 antibody. Transfected Chinese hamster ovary cells showed positive membrane staining. CONCLUSION: We have identified a population of neuroendocrine cells in the human pancreas and duodenum that express beta3-adrenergic receptors. These cells appear to be somatostatin D cells. 相似文献
88.
89.
Ramesh C. Dhiman Sharmila Pahwa G. P. S. Dhillon Aditya P. Dash 《Parasitology research》2010,106(4):763-773
It is unequivocal that climate change is happening and is likely to expand the geographical distribution of several vector-borne
diseases, including malaria and dengue etc. to higher altitudes and latitudes. India is endemic for six major vector-borne
diseases (VBD) namely malaria, dengue, chikungunya, filariasis, Japanese encephalitis and visceral leishmaniasis. Over the
years, there has been reduction in the incidence of almost all the diseases except chikungunya which has re-emerged since
2005. The upcoming issue of climate change has surfaced as a new threat and challenge for ongoing efforts to contain vector-borne
diseases. There is greater awareness about the potential impacts of climate change on VBDs in India and research institutions
and national authorities have initiated actions to assess the impacts. Studies undertaken in India on malaria in the context
of climate change impact reveal that transmission windows in Punjab, Haryana, Jammu and Kashmir and north-eastern states are
likely to extend temporally by 2–3 months and in Orissa, Andhra Pradesh and Tamil Nadu there may be reduction in transmission
windows. Using PRECIS model (driven by HadRM2) at the resolution of 50 × 50 Km for daily temperature and relative humidity
for year 2050, it was found that Orissa, West Bengal and southern parts of Assam will still remain malarious and transmission
windows will open up in Himachal Pradesh and north-eastern states etc. Impact of climate change on dengue also reveals increase
in transmission with 2 C rise in temperature in northern India. Re-emergence of kala-azar in northern parts of India and reappearance
of chikungunya mainly in southern states of India has also been discussed. The possible need to address the threat and efforts
made in India have also been highlighted. The paper concludes with a positive lead that with better preparedness threat of
climate change on vector-borne diseases may be negated. 相似文献
90.
J Dhillon R Fielding J Adler-Moore R L Goodall D Mitchison 《The Journal of antimicrobial chemotherapy》2001,48(6):869-876
Most of the amikacin in low-clearance liposomal amikacin is excreted very slowly, offering the possibility of maintaining effective treatment of pulmonary tuberculosis with widely separated supervised doses. As a preliminary to explorations in humans, its efficacy was assessed in acute experimental murine tuberculosis by weekly counts of viable bacilli in spleen and lungs over a 4 week period. Liposomal amikacin in dosages of 160, 80 and 40 mg/kg given iv three times a week was 2.4-5.0 times more active than free amikacin and 6.6-6.7 times more active than streptomycin with the non-liposomal drugs given im five times a week. When the free amikacin and the streptomycin were also given iv three times a week, liposomal amikacin was 2.7-2.9 times more active than free amikacin and 3.7-5.6 more active than streptomycin. In a model of chronic tuberculosis, initial BCG vaccination was followed by challenge with virulent Mycobacterium tuberculosis and a 2 week stabilization period. Thereafter, treatment with liposomal amikacin 160 and 80 mg/kg three times a week for the first 4 weeks and then once a week for a further 4 weeks, had greater initial bactericidal activity than free amikacin 160 mg/kg five times a week, but had less eventual sterilizing activity than five times a week oral isoniazid 25 mg/kg or rifampicin 15 mg/kg. Although low-clearance liposomes increased the safety, potency and dosing interval of amikacin in these models, all aminoglycosides, including liposomal amikacin, were only bactericidal in the presence of bacillary metabolism and growth. 相似文献