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1.
The aim of this study was to determine whether patients with sickle cell disease (SCD) in steady state had pulmonary abnormalities seen on high-resolution computed tomography (HRCT) and whether any abnormalities correlated with contemporaneously diagnosed lung function abnormalities. A subsidiary question was whether the results of a noninvasive measure of haemolysis (end-tidal carbon monoxide (ETCO) levels) correlated with pulmonary function abnormalities. Thirty three patients with SCD, median (range) age 36 yrs (17-67 yrs) were examined. The degree of lobar volume loss and ground-glass opacification and prominence of central vessels on HRCT were quantitatively assessed. Pulmonary function was assessed by measurements of lung volumes, spirometry, gas transfer and oxygen saturation. ETCO levels were measured using an end-tidal CO monitor. Forced expiratory volume in one second (FEV1), forced vital capacity and total lung capacity significantly correlated with HRCT findings, particularly lobar volume loss. ETCO levels significantly negatively correlated with FEV1, vital capacity measured using a plethysmograph, specific airway conductance and arterial oxygen saturation measured by pulse oxymetry. In conclusion, the present results suggest that high-resolution computed tomography noninvasive assessment of haemolysis might be useful to identify sickle cell disease patients with respiratory function impairment.  相似文献   
2.
Benign intracranial hypertension (BIH) is reported in three children from Australia and one from New Zealand, who were being treated with recombinant human growth hormone (rhGH). Three males and one female, aged between 10.5 and 14.2 y, developed intracranial hypertension within 2 weeks to 3 months of starting treatment. A national database, OZGROW, has been prospectively collecting data on all 3332 children treated with rhGH in Australia and New Zealand from January 1986 to 1996. The incidence of BIH in children treated with growth hormone (GH) is small, 1.2 per 1000 cases overall, but appears to be greater with biochemical GHD (<10IUml -1), i.e. 6.5/1000 (3 in 465 cases), relative risk 18.4, 95% confidence interval 1.9-176.1, than in all other children on the database. The incidence in patients with Turner's syndrome was 2.3/1000 (1 in 428 cases). No cases in patients with partial GHD (10–20 IUml -1) or chronic renal failure were identified. Possible causative mechanisms are discussed. The authors'practice is now to start GH replacement at less than the usual recommended dose of 14IUm-2 week-1 in those children considered to be at high risk of developing BIH. Ophthalmological evaluation is recommended for children before and during the first few months following commencement of rhGH therapy and is mandatory in the event of peripheral or facial oedema, persistent headaches, vomiting or visual symptoms. The absence of papilledema does not exclude the diagnosis.  相似文献   
3.
The observation of high levels of xenobiotic metabolizing enzyme activity in the olfactory mucosa has produced speculation on the functional significance of these enzymes in the nose. Hypothesized roles include protection of the nasal epithelium, lung, and other downstream tissues, and termination or modification of olfactory responses. The enzyme rhodanese metabolizes cyanide, which is a commonly inhaled toxicant and an odorant and therefore of interest to both toxicologists and olfactory neurobiologists. The cellular localization of this enzyme within the olfactory mucosa will have important consequences for its ability to protect specific cells, as well as its ability to alter the concentration of inhaled cyanide at receptors, and therefore could provide clues as to its function in this tissue. We have compared the distribution of this enzyme in two species, the rat and the cow, using immunohistochemical localization techniques employing species-specific polyclonal antisera raised in our laboratory. In the rat, rhodanese-like immunoreactivity was greatest within the apical portion of the sustentacular cells, the basal cells, and the duct cells of Bowman's glands. Very little to no reaction was observed in the acinar cells of Bowman's glands. In the cow, however, the acinar cells and duct cells of Bowman's glands showed intense immunoreactivity with little to no reaction observed in the sustentacular or basal cells. The differences in localization of rhodanese in these two species may have important implications for cell types at risk during inhalation of cyanide or organonitrile compounds metabolized to cyanide within the nasal mucosa. In addition, the difference in distribution in the two species emphasizes the importance of considering enzyme activity and localization in the determination of an appropriate animal model for study of both nasal toxicology and olfactory responsiveness in humans.  相似文献   
4.
A case is described in which a deep palmo-planar wart (myrmecia) caused erosion of the underlying phalanx.  相似文献   
5.
In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population.  相似文献   
6.
We have investigated whether an alternating induction chemotherapy regimen of PVB/BEP is superior to BEP in patients with poor-prognosis testicular non-seminoma. A total of 234 eligible patients were randomised to receive an alternating schedule of PVB/BEP for a total of four cycles or four cycles of BEP. Poor prognosis was defined as any of the following: lymph node metastases larger than 5 cm, lung metastases more than four in number or larger than 2 cm, haematogenic spread outside the lungs, such as in liver and bone, human chorionic gonadotrophin > 10,000 IU l-1 or alphafetoprotein > 1000 IU l-1. The complete response (CR) rates to PVB/BEP and BEP were similar, 76% and 72% respectively (P = 0.58). In addition, there was no significant difference in relapse rate, disease-free and overall survival at an average follow-up of 6 years. The 5-year progression-free and survival rates in both treatment groups were approximately 80%. The PVB/BEP regime was more toxic with regard to bone marrow function; the frequencies of leucocytes below 1000 microliters-1, leucocytopenic fever and platelets below 25,000 microliters-1, throughout four cycles were 28% vs 5% (P < 0.001), 16% vs 5% (P = 0.006), and 10% vs 1% (P = 0.001) respectively. Neuropathy also occurred more often in the PVB/BEP arm: 47% vs 25% (P = 0.001). This study shows that an alternating regimen of PVB/BEP is not superior to BEP and that it is more myelo- and neurotoxic.  相似文献   
7.
There has been concern about the number of interval cancers which have been detected within the National Breast Screening Programme. A series of 134 women presenting with interval cancers was studied by prospective audit and the rate and radiological classification of the tumours determined. The cancers were classified as true (67), false-negative (22), unclassifiable (28), occult (12), and minimal sign (5). The interval cancer rate did not achieve the new National Guidelines in either the first 2 years or the 3rd interval year. The false-negative cancers presented mainly in the 1st interval year, whereas the true cancers were predominantly confined to the 2nd and 3rd years. These data suggest that alterations to the screening programme may be beneficial. It may be, however, that the programme is still on the learning curve and this should be taken into account when interpreting these data.  相似文献   
8.
Bottomley  PA; Lee  Y; Weiss  RG 《Radiology》1997,204(2):403
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9.
10.
Tamoxifen (TAM) has previously been shown to inhibit growth of the Dunning R3327 rat prostate adenocarcinoma and to elevate serum prolactin levels. The purpose of this study was to determine the role of prolactin in modulating the effects of tamoxifen on growth of the R3327 prostatic adenocarcinoma. Intact and castrated Copenhagen-Fischer male rats bearing the Dunning R3327 rat prostatic tumor were divided into groups and injected sc five times per week for 16 weeks as follows: vehicle; TAM (0.5 mg/kg); haloperidol (HALO; 0.5 mg/kg); bromocriptine (CB-154; 5 mg/kg); TAM plus HALO; or TAM plus CB-154. In both intact and castrated rats, agents that either raised (HALO) or lowered (CB-154) serum prolactin had little effect on prostatic tumor growth when administered singly. In intact rats, average tumor diameter in vehicle-treated controls increased 421% 16 weeks after the start of the experiment, and treatment with TAM or TAM plus HALO reduced this tumor growth by approximately one-half. Interestingly, CB-154 administered in combination with TAM completely blocked TAM inhibition of tumor growth in intact rats. In contrast to these results in intact rats, average tumor diameter increased 129% in TAM- and 118% in TAM plus HALO-treated castrated rats and was significantly greater than the characteristic retardation of tumor growth (49% increase) that occurred in the vehicle-treated castrate controls. In addition, combined treatment of TAM plus CB-154 in castrate rats resulted in an even greater increase (188%) in average tumor diameter. The inhibitory effect of TAM on R3327 prostatic tumor growth in intact rats appears to be an indirect effect resulting from its ability to reduce serum testosterone levels. In contrast, the stimulatory effect of TAM in castrate rats appears to result directly from an estrogen-like action, which can directly enhance prostatic tumor growth in the presence of low levels of circulating androgens; this stimulatory effect of TAM is more pronounced when prolactin levels are suppressed by CB-154. Clearly, castration alone is more effective than TAM therapy alone or in combination with castration in the retardation of the growth of the androgen-dependent R3327 prostatic tumor in rats.  相似文献   
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