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41.
An intracranial mixed germ cell tumour with germinoma and teratoma components is reported. The patient presented with parinaud's syndrome and precocious puberty. The treatment involved partial surgical debulking followed by whole brain radiotherapy (4500 cGY in 25 fraction over 5 weeks) and chemotherapy (consisting of cisplatin and etoposide). Post treatment MRI showed no residual lesion. The controversies in the management are discussed. 相似文献
42.
Chopra RK Bhagavan HN 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》1999,69(2):92-95
There are several reports in the literature on the relative bioavailabilities of RRR (natural) vs. all-rac (synthetic) forms of vitamin E in humans and animal models but none on the bioavailability of alpha-tocopherol in mixed vitamin E formulations. In the present study we examined the bioavailability of alpha-tocopherol in a typical commercially available product containing mixed tocopherols. We also tested a formulation containing all-rac-alpha-tocopherol with mixed tocopherols for purposes of comparison along with straight RRR- and all-rac-alpha-tocopheryl acetate as reference products. Normal male subjects were given one of the four formulations of vitamin E (800 IU per day in softgel capsule form for 10 days): 1. All-rac-alpha-tocopheryl acetate, 2. RRR-alpha-tocopheryl acetate, 3. RRR-alpha-tocopherol with mixed tocopherols, and 4. all-rac-alpha-tocopherol with mixed tocopherols. Both serum alpha- and gamma-tocopherols were determined by HPLC at baseline, and at days 2, 4, 7 and 10. The values for alpha- at baseline and 10 days were 0.80, 0.80, 0.80 & 0.79 mg/dl and 1.67, 1.72, 1.76 & 1.62 mg/dl. The values for gamma- were 0.28, 0.29, 0.30 & 0.29 mg/dl and 0.11, 0.08, 0.10 & 0.10 mg/dl. Thus the data show that a) the bioavailability of RRR- and all-rac-alpha-tocopherols is not affected by other tocopherols, and b) both RRR- and all-rac-alpha-tocopherol (free or esterified) significantly suppress the serum gamma tocopherol to the same extent. Furthermore, since there was no difference in the serum values of alpha-tocopherol between RRR- and all-rac-vitamin E given the same dose as IUs, the data also support the currently accepted ratio of 1.36 for the biopotency of RRR- vs. all-rac-alpha-tocopheryl acetate. 相似文献
43.
Chopra A Bahl RK Puri RK Gill SS 《Indian journal of dermatology, venereology and leprology》1996,62(2):110-111
A 45-year-old woman with livid plaques showing central atrophy and erythematous vesicular borders over both dorsa of feet and buttocks, and follicular and papular lesions over buttocks and lumbar area, was difficult to diagnose as either lichen planus (LP) or lupus erythematosus (LE). The histological studies from two places showed features of both LE and LP. Laboratory findings were within normal limits first, but follow up studies for two years showed persistent albuminurea, leucopenia, arthritis and erythema over the exposed areas with same histology suggesting that eruption may be an unusual variant of LE. 相似文献
44.
45.
Lung clearance of soluble radioaerosols of different molecular weights in systemic sclerosis. 总被引:5,自引:5,他引:0
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Clearance rates of soluble radioaerosols of sodium pertechnetate (99mTcO4; mol wt 163) and diethylenetriaminepenta-acetate (99mTc-DTPA; mol wt 492) were determined in seven normal subjects and ten patients with systemic sclerosis affecting the lungs. Twenty millicuries (mCi) each of 99mTcO4 and 99mTc-DTPA in 5 ml saline were aerosolised and inhaled using a disposable "Blount" nebuliser on two different days. Two regions of interest over each posterior lung field were monitored with scintillation camera, and data were stored on magnetic tape using a Hewlett Packard Data Analyser. Decreasing levels of radioactivity were plotted semilogarithmically and half-time (T 1 1/2) removal rates were calculated. The T 1 1/2) values in normal subjects did not differ significantly from T 142 values of the patients with TcO4. However, the removal rates of the higher molecular weight solute were significantly faster from lower lung zones in patients with systemic sclerosis than in the normal subjects. The faster absorption of DTPA from lower lung zones of the patients could be due to regional abnormalities of alveolar epithelium at the lung bases, presumably as a result of greater retractive forces secondary to fibrosis. 相似文献
46.
Rehan Asif Kamlesh Chandra Vanita Chopra M. L. B. Bhatt 《Indian journal of otolaryngology and head and neck surgery》2003,55(2):94-96
Management of Head and Neck Cancers poses a challenge inspite of several advances because of poor success in terms of response
rate, survival and reduced morbidity of the patients. In the present study 30 untreated histologically proven cases of head
and neck cancers were subjected to weekly radiotherapy with adjuvant chemotherapy (cisplatin 30 mg/m2 intravenously). This study group was compared with a group of 30 patients who were given only radiotherapy. Results have
shown that combination of chemotherapy with radiotherapy gives a significantly better results in tumour as well as nodal response
with minimal toxicities. 相似文献
47.
48.
Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung 总被引:1,自引:0,他引:1
Prahalad AK; Ross JA; Nelson GB; Roop BC; King LC; Nesnow S; Mass MJ 《Carcinogenesis》1997,18(10):1955-1963
Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic
hydrocarbon, is the most potent carcinogen ever tested in mouse skin and
rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction,
tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in
strain A/J mouse lung. Groups of mice received a single i.p. injection of
0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment,
DNA adducts were measured at times between 1 and 28 days, while tumors were
counted at 250 days and analyzed for the occurrence of point mutations in
codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung
induced six major and four minor DNA adducts. Maximal levels of adduction
occurred between 5 and 10 days after injection followed by a gradual
decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti-
and syn-11,12- dihydroxy-13,14-epoxy-
11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both
deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed
by cochromatography. The major adduct was identified as a product of the
reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced
significant numbers of lung adenomas in a dose- dependent manner, with the
highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In
tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based
on the administered dose, DB[a,l]P was more active than other environmental
carcinogens including benzo[a]pyrene. As a function of time-integrated DNA
adduct levels, DB[a,l]P induced lung adenomas with about the same potency
as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar
in carcinogenic potency to other PAHs in the strain A/J mouse lung model.
Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors
revealed the predominant mutations to be G-->T transversions in the
first base of codon 12, A-->G transitions in the second base of codon
12, and A-->T transversions in the second or third base of codon 61,
concordant with the DNA adduct profile.
相似文献
49.
Twenty-seven patients with idiopathic palmoplanter hyperhidrosis were treated with Iontotherapy over a one year period. In twenty-four cases there was a good response but maintenance therapy was required every 3-4 weeks.KEY WORDS: Iontophoresis, Palmoplanter hyperhidrosis 相似文献
50.