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1.
Gallstones are common and their incidence increases with age.1 Fifty per cent of these stones are in the common bile duct (CBD) in the elderly.2 Most of them are silent but with time there is an increasing chance of developing symptoms which are more likely to be serious in the elderly.3 Failure to relieve mechanical obstruction of bile flow may lead to secondary biliary cirrhosis.4 It has been estimated that on average secondary biliary cirrhosis develops some seven years after the onset of obstruction from a stricture, four and half years after gallstone obstruction and 10 months after the onset of malignant stricture.5 The characteristic features are the pathological findings of portal-portal linkages, with a pattern of monolobular cirrhosis and the preservation of normal vascular relationships.6 Secondary biliary cirrhosis may lead to hepatic insufficiency and portal hypertension with the resultant complications, such as bleeding oesophageal varices, hypersplenism with pancytopenia, ascites and encephalopathy. We describe a patient in whom the diagnosis was not suspected until laparotomy and confirmed only at autopsy.  相似文献   
2.
The role of open lung biopsy (OLB) in the diagnosis of the etiology of lung infiltrates in children was analyzed for a 10-year period 1979-1989 in a tertiary referral center. A total of 18 children had 19 lung biopsies to ascertain the cause of lung infiltrates. Thirteen of these children (72 %) were immunocompromised due to treatment of hematological/solid malignancies and bone marrow transplantation. The clinical diagnosis was bilateral lung infiltrates of unknown etiology in 17 of 18 children. Eight of these children were ventilated for respiratory failure. The biopsy was useful in achieving a histological diagnosis in 18 of 19 samples (diagnostic yield 95%) and an etiological diagnosis in 14 of 19 samples (etiological yield 74 %). Therapeutic strategy was altered in 14 of 18 patients based on the biopsy results. Five of 14 patients responded favorably to a change in specific treatment. The lime interval from onset of respiratory illness to biopsy was 2-60 days (mean 16 days). Despite the critical state of these children there were few complications associated with the biopsy and no mortality directly related to the procedure. We recommend that OLE be undertaken sooner rather than later in immunocompromised children with bilateral pulmonary infiltrates of unknown etiology.  相似文献   
3.
Currently, antiretroviral therapy has become more affordable even in developing countries and it is being used in India. Fifteen HIV-1 infected individuals, who were on highly active antiretroviral therapy (HAART), were followed up for an average period of one year. The plasma viral load and CD4+ T cell estimation done at mean intervals of 5 months and 11 months after initiation of therapy showed a good response to therapy in 14 (93%) individuals.  相似文献   
4.
5.
HPV DNA in plasma of patients with cervical carcinoma.   总被引:4,自引:0,他引:4  
BACKGROUND: HPV DNA has been detected in metastatic tumour and HPV plasma viraemia may indicate a poor prognosis and a high risk for metastasis. OBJECTIVE: Detection of HPV DNA in plasma of patients with cervical carcinoma. STUDY DESIGN: A cross-sectional study was done, wherein cervical biopsies and plasma samples were collected from 58 women with invasive cervical carcinoma, 10 women with cervical intraepithelial neoplasia (CIN) and 30 control women in the same age range. Polymerase chain reaction (PCR) was employed to detect the presence of HPV DNA. Samples positive for HPV DNA were typed by restriction fragment length polymorphism (RFLP). To confirm that the HPV sequence in plasma was identical to that in tissue, sequencing was done on all the paired plasma and tissue samples. RESULTS: All the 30 paired cervical tissue and plasma samples from the controls were negative for HPV DNA. HPV DNA was detectable in cervical tissues of 55 (94.8%) of 58 patients with invasive cervical carcinoma and in all 10 patients (100%) with CIN and in eight (11.8%) of the total 68 plasma samples from patients. All eight plasma samples were from women with invasive cervical carcinoma with three each in stages IIIB and IV and one each in stages IIB and IB, respectively. Of the eight positive samples, seven were typed as HPV-16 and 1 as HPV-58. HPV types detected in cervical tissue and plasma pairs from these eight patients correlated as revealed by RFLP and sequencing. A patient with stage IB cancer had detectable HPV DNA in the external iliac lymph node, removed at Wertheims hysterectomy, which was histopathologically free of tumour. The HPV type in the node, was the same as that present in the paired tissue and plasma sample. CONCLUSIONS: HPV DNA is detectable in the plasma of patients with advanced cervical cancer.  相似文献   
6.
Background: Individuals ascending to high altitude are at a risk of getting acute mountain sickness (AMS). The present study is a network meta-analysis comparing all the interventions available to prevent AMS.

Methods: Electronic databases were searched for randomized clinical trials evaluating the use of drugs to prevent AMS. Incidence of AMS was the primary outcome and incidence of severe AMS, paraesthesia (as side effect of acetazolamide use), headache and severe headache, and oxygen saturation were the secondary outcomes. Odds ratio [95% confidence interval] was the effect estimate for categorical outcomes and weighted mean difference for oxygen saturation. Random effects model was used to derive the direct and mixed treatment comparison pooled estimates. Trial sequential analysis and grading of the evidence for key comparisons were carried out.

Results: A total of 24 studies were included. Acetazolamide at 125, 250 and 375?mg twice daily, dexamethasone and ibuprofen had statistically significant lower incidence of AMS compared to placebo. All the above agents except ibuprofen were also observed to significantly reduce the incidence of severe AMS. Acetazolamide alone or in combination with Ginkgo biloba were associated with lower incidence of headache, but higher risk of paraesthesia. Acetazolamide at 125?mg and 375?mg twice daily significantly reduce the incidence of severe headache as like ibuprofen. Trial sequential analysis indicates that the current evidence is adequate for the incidence of AMS only for acetazolamide 125 and 250?mg twice daily. Similarly, the strength of evidence for acetazolamide 125 and 250?mg twice daily was moderate while it was either low or very low for all other comparisons.

Conclusions: Acetazolamide at 125, 250 and 375?mg twice daily, ibuprofen and dexamethasone significantly reduce the incidence of AMS of which adequate evidence exists only for acetazolamide 125 and 250?mg twice daily therapy. Acetazolamide 125?mg twice daily could be the best in the pool considering the presence of enough evidence for preventing AMS and associated with lower incidence of paraesthesia.
  • Key messages
  • Acetazolamide 125, 250 and 375?mg twice daily, dexamethasone and ibuprofen reduce the incidence of AMS in high altitudes.

  • Adequate evidence exists supporting the use of acetazolamide 125?mg and 250?mg twice daily for preventing AMS of which acetazolamide 125?mg twice daily could be the best.

  相似文献   
7.
The alterations in serum levels of T3, T4, TSH and TBG, TSH response to 100 mug iv TRH, and urinary excretion of T3 and T4 were studied in 8 healthy men at sea level (SL), on days 1, 2, 4, 8 and 16 after arrival by air at high altitude (3,700 m, HA), and during days 5 to 7 after their return to SL. No significant alterations in serum levels of TSH and TBG or TSH response to TRH were observed during exposure to HA or on return to SL. There was, however, an acute elevation in both serum total T3 and T4. Serum total T3 from a mean basal+/-SE value of 128+/-13 ng/dl increased to 320+/-18 on day 1 and remained significantly elevated at 225+/-48 up to day 8 after arrival at high altitude. Similarly serum total T4 increased from basal level of 9+/-0.92 mug/dl to 15.2+/-1.2 and remained elevated till day 16 and it was 11+/-1.19 mug/dl during days 5 to 7 after return to SL. The urinary excretion of both T3 and T4 was decreased. These changes perhaps were the result of complex physiologic adjustments on acute exposure to high altitude, like shrinkage of the T3 and T4 distribution pools, altered binding capacities of thyroid hormones binding proteins, and a reduction in clearance of thyroid hormones from the plasma compartment; and were probably not suggestive of an enhanced thyroid activity. Their actual significance in high altitude adaptation in man is not clearly understood.  相似文献   
8.
Objectives: The purpose of this study was to establish that the prostacyclin (PGI2) receptor (IP receptor) is present on rabbit and human erythrocytes and that its activation stimulates cyclic adenosine monophosphate (cAMP) synthesis and adenosine triphosphate (ATP) release. Methods: The effect of incubation of erythrocytes with the active PGI2 analogs, iloprost or UT‐15C, on cAMP levels and ATP release was determined in the absence and presence of the IP receptor antagonist, CAY10441. Western analysis was used to determine the presence of the IP receptor on isolated membranes. To establish that effects of PGI2 analogs were not due to prostaglandin E2(PGE2) receptor activation, the effect of PGE2 on cAMP levels and ATP release was determined. Results: Rabbit and human erythrocytes possess IP receptors. Iloprost and UT‐15C stimulated increases in cAMP and ATP release that were prevented by the IP receptor antagonist, CAY10441. PGE2 did not stimulate cAMP accumulation or ATP release and did not inhibit iloprost‐induced increases in cAMP. Conclusions: This study establishes that the IP receptor is present on rabbit and human erythrocytes and that its activation results in increases in cAMP and ATP release. These results suggest a novel mechanism by which PGI2 and its active analogs, when administered pharmacologically, could produce vasodilation.  相似文献   
9.
Burkitt's lymphoma(BL) is an aggressive form of nonHodgkin's B-cell lymphoma with three variants namely endemic, sporadic, and immunodeficiency-associated types. It is endemic in Africa and sporadic in other parts of the world. While the endemic form is widely reported to occur in early childhood and commonly involves the jaw bones, the sporadic form typically presents as an abdominal mass. This presentation reports a rare case of sporadic form of BL clinically manifesting as a generalized gingival enlargement in an immunocompetent adult male which demonstrated an aggressive behavior. The patient reported with a prominent anterior gingival swelling of 6 mo duration which slowly enlarged in size and associated with multiple lymph node involvement. Microscopic examination of the lesion using H, E and immunohistochemical diagnosis confirmed the diagnosis as BL. The patient succumbed to the disease before any therapy could be instituted. Since a wide array of causes can be attributed to gingival enlargements, it is necessary to consider malignancies as one of the important differential diagnosis so as to facilitate the need for appropriate diagnosis and prompt treatment.  相似文献   
10.
BackgroundRanolazine inhibits late Na+ and K+ currents. Earlier studies have reported an antiarrhythmic effect. The aim of the present study was to understand whether ranolazine could still preserve its antiarrhythmic properties in the settings of chronic heart failure (CHF).Methods and ResultsIn 12 female rabbits, CHF was induced by 4 weeks of rapid ventricular pacing leading to a decrease in ejection fraction. Twelve rabbits underwent sham operation. Isolated hearts were Langendorff perfused and demonstrated a significant QT prolongation after induction of heart failure. Ranolazine caused a concentration-dependent (10 and 30 μmol/L) increase of action potential duration (APD90) in sham-operated and failing hearts. Eight endo- and epicardial monophasic action potentials revealed a nonsignificant increase in spatial and temporal dispersion of repolarization. The increase in APD90 was accompanied by a greater increase in refractory period, resulting in a significant increase in postrepolarization refractoriness in sham-operated (+29 ms and +55 ms; P < .01) and failing (+22 ms and +30 ms; P < .05) hearts. In control conditions, programmed ventricular stimulation and a burst pacing protocol led to ventricular fibrillation (VF) in 5 of the 12 sham-operated (6 episodes) and in 7 of the 12 failing (18 episodes) hearts. In the presence of ranolazine, VF was inducible in only 2 of 12 failing hearts (5 episodes). In the presence of low [K+], only 1 ranolazine-treated sham-operated heart developed early afterdepolarizations and ventricular tachyarrhythmias despite significant QT prolongation.ConclusionsRanolazine decreases inducibility of VF in the presence of a significant increase in postrepolarization refractoriness. This antiarrhythmic effect in the intact heart is preserved in CHF and is not associated with drug-induced proarrhythmia.  相似文献   
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