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91.
C. Caramella F. Ferrari M. C. Bonferoni M. E. Sangalli M. De Bernardi Di Valserra F. Feletti M. R. Galmozzi 《Biopharmaceutics & drug disposition》1993,14(2):143-160
Six preparations were considered: three multiple unit dosage forms (micropellets in capsules) (D, E and G) and one matrix tablet (B) were experimental prolonged release formulations, two non-disintegrating tablets (A and C) were commercial products. The in vitro dissolution behaviour of the differing formulations was investigated using the USP XXII paddle apparatus. The in vivo study was effected on a panel of 12 healthy volunteers. The two commercial tablets (A and C) showed mean dissolution time (MDT) of 1.34 and 1.44 h and td of 91 and 92 min, respectively; for prolonged release formulations (B, E, D, and G) MDT ranged between 2.28 and 4.23 h and td between 149 and 291 min. The mean residence time (MRT) was 8.68 and 6.47 h for tablets A and C, respectively; it ranged between 9.62 and 10.24 h for the multiple unit formulations E, D, and G and was 11.27 h for matrix B. Formulation B also showed the higher apparent elimination half-life t1/2 (7.12 h), while apparent t1/2 for all the other formulations were very similar, ranging between 5.04 and 5.28 h. High variability between the various formulations was found for Cmax and AUC values, and no relationships could be established with the type of formulation. An in vitro/in vivo correlation was found for all the formulations examined on the basis of analogous parameters (MDT and MRT); (r = 0.83, p <0.05). In a few cases the Wagner-Nelson deconvolution method was applied to individual plasma level versus time curves and the corresponding absorption curves were obtained. In these cases the in vitro/in vivo correlation was tested on the basis of the comparison of the in vivo absorption curves with the in vitro dissolution profiles. This was accomplished using the ‘Levy's plot’ (per cent released versus per cent absorbed) approach and provided further support for the correlation found. 相似文献
92.
93.
Ronald J. Hogg Fred G. Silva Philip L. Berry James E. Wenz 《Pediatric nephrology (Berlin, Germany)》1993,7(1):27-31
We report clinical and pathological data in 56 adolescents presenting with gross hematuria (GH) and 65 presenting with idiopathic nephrotic syndrome (INS). IgA nephropathy (present in 52%) and other mesangial lesions were found in the majority of the 56 patients with GH. Many of these patients had complex urological procedures prior to consideration of a nephrological problem. This often led to significant delays in making the appropriate diagnosis. Pathological lesions in the 65 patients with INS included minimal change NS (MCNS) in 31%, membranous glomerulonephritis (MGN) and focal segmental glomerulosclerosis (FSGS) in 18.5% each, and membranoproliferative GN (MPGN) in 12%. In 47 of the patients with INS, in whom no specific treatment had been given prior to renal biopsy, MCNS and MGN were observed with a similar frequency (26% and 23%, respectively), with FSGS and MPGN being found in 21% and 11%. These results indicate that the pathological lesions in adolescents with INS who undergo a renal biopsy more closely resemble those in adults, and are usually more severe than those in young children. However, it should be noted that our study was retrospective. Hence, there were probably some adolescents with INS who had a successful response to therapy and therefore did not have a renal biopsy performed.
Southwest Pediatric Nephrology Study Group (Central Office, Baylor University Medical Center at Dallas, Tex., USA). Director, Ronald J. Hogg; Associate Directors, Fred G. Silva and F. Bruder Stapleton; Statistician, Joan S. Reisch; Administrative Assistant, Kaye Green. Participating Centers—Baylor College of Medicine, Houston, Tex.: Phillip L. Berry, L. Leighton Hill, Sami A, Sanjad, Edith Hawkins; Baylor University Medical Center, Dallas, Tex.: Ronald J. Hogg, Kaye Green; Tulane University Medical Center, New Orleans, La.: Frank Boineau, John E. Lewy, Radhakrishna Baliga, Patrick Walker; University of Arkansas, Little Rock, Ark.: Watson Arnold, Eileen Ellis, Edward Uthman; University of Colorado Health Science Center, Denver, Colo.: Gary M. Lum, Wiliam Hammond; University of Oklahoma Medical Center, Oklahoma City, Okla.: James Wenzl, James Matson, Geoffrey Altshuler, Sarah Johnson; University of Tennessee, Memphis, Tenn.: F. Bruder Stapleton, Shane Roy, III, Robert J. Wyatt, Charles McKay, William Murphy; University of Texas Health Science Center at Dallas, Tex.: Billy S. Arant Jr, Michel Baum, Fred G. Silva, Arthur Weinberg, Craig Argyle, Joseph Rutledge, Ed Eigenbrodt; University of Texas Medical School, Houston, Tex.: Susan B. Conley, Jacques Lemine, Ron Portman, Ann Ince, Regina Verani; University of Texas Health Science Center at San Antonio, Tex.: Michael Foulds, Sudesh Makker, Kanwal Kher, Melanie Sweet, Victor Saldivar, Fermin Tio; University of Texas Medical Branch, Galveston, Tex.: Ben H. Brouhard, Alok Kalia, Luther B. Travis, Lisa Hollander, Tito Cavallo, Srinivasan Rajaraman; University of Utah Medical Center, Salt Lake City; Utah: Eileen Brewer, Richard Siegler, Elizabeth Hammond, Theodore Pysher.
Note that this list reflects the investigators' addresses and positions during the period of this study and not necessarily their current situations. 相似文献
94.
Total parenteral nutrition is now a broadly used method whose efficacy is confirmed, even if it is still not free from risk of complications. The Authors report their own clinical experience on 130 cases in the period 1981-1988. Complications were registered in 4.6% of the observed cases. They underline the problems relating to this subject. 相似文献
95.
Diagnosis of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes in a Chinese family by PCR/restriction enzyme analysis 总被引:1,自引:0,他引:1 下载免费PDF全文
C W Lam K Jain K Y Chan D K Silva Y W Chan L J C Wong 《Journal of clinical pathology》1995,48(5):M285-M288
The clinical presentation and the biochemical and molecular genetic findings are described in a 13 year old Chinese boy with MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes). The diagnosis was initially suspected because of the characteristic clinical features and the strong family history of convulsions. Using polymerase chain reaction—restriction enzyme analysis, the heteroplasmic nt3243 A→G mutation in mtDNA of peripheral blood leucocytes and a muscle sample was demonstrated. The oligosymptomatic relatives were then screened by this method and the degree of heteroplasmy was analysed. This appears to be the first report of a MELAS family in Hong Kong with this described mutation. Molecular genetic techniques are advantageous in the diagnosis of MELAS. 相似文献
96.
Razeq Shetab Stuart H. Cohen Thomas Prindiville Yajarayma J. Tang Mary Cantrell Darush Rahmani Joseph Silva Jr. 《Journal of clinical microbiology》1998,36(6):1729-1732
Bacteroides fragilis constitutes about 1% of the bacterial flora in intestines of normal humans. Enterotoxigenic strains of B. fragilis have been associated with diarrheal diseases in humans and animals. The enterotoxin produced by these isolates induces fluid changes in ligated intestinal loops and an in vitro cytotoxic response in HT-29 cells. We developed a nested PCR to detect the enterotoxin gene of B. fragilis in stool specimens. After DNA extraction, a 367-bp fragment was amplified with two outer primers. The amplicon from this reaction was subjected to a second round of amplification with a set of internal primers. With these inner primers, a 290-bp DNA fragment was obtained which was confirmed as part of the B. fragilis enterotoxin gene by Southern blotting with a nonradioactive internal probe and a chemiluminescence system. By this approach, B. fragilis enterotoxin gene sequences were detected in eight known enterotoxigenic human isolates and nine enterotoxigenic horse isolates. No amplification products were obtained from DNA extracted from 28 nonenterotoxigenic B. fragilis isolates or B. distasonis, B. thetaiotaomicron, B. uniformis, B. ovatus, Escherichia coli, or Clostridium difficile. The sensitivity of this assay allowed us to detect as little as 1 pg of enterotoxin DNA sequences or 100 to 1,000 cells of enterotoxigenic B. fragilis/g of stool. Enterotoxin production of all isolates was confirmed in vitro in HT-29 cells. A 100% correlation was obtained between enterotoxin detection by cytotoxin assay and the nested PCR assay. This rapid and sensitive assay can be used to identify enterotoxigenic B. fragilis and may be used clinically to determine the role of B. fragilis in diarrheal diseases. 相似文献
97.
Physician based surveillance system for occupational respiratory diseases: the experience of PROPULSE, Québec, Canada. 总被引:1,自引:0,他引:1 下载免费PDF全文
OBJECTIVE: To evaluate the feasibility of implementing a physician based surveillance system of occupational respiratory diseases (PROPULSE) in Québec with regard to physician participation rate, characteristics of reported cases, and comparison with official statistics from the Workers' Compensation Board (WCB). METHODS: All chest physicians and allergists in Québec were asked to report suspected new cases of occupational respiratory diseases, on a monthly basis, between October 1992 and September 1993. For each case, personal information was collected and the physician's opinion on whether the condition was related to work was categorised as highly likely, likely, and unlikely. RESULTS: Of the 161 physicians initially approached, 68% participated. Physicians rated 48% of suspected cases as highly likely, 29% as likely, and 20% as unlikely. The most often reported diagnosis was asthma (63%), followed by diseases related to asbestos (16%). Silicosis was less frequent (5%) but it was reported for six workers under 40 of whom five were involved in sandblasting activities. The high proportion of cases of asthma probably reflects the increasing importance of this disease but may also reflect the different patterns of reporting among physicians with different expertise. The distribution of cases by diagnostic category is quite different between the PROPULSE system and that of the WCB (annual mean number of compensated cases during a four year period). Asthma and allergic alveolitis are more frequent in PROPULSE, reactive airways dysfunction syndrome are about the same in both systems, and other diseases are more frequent among compensated cases. The most frequent sensitising agents reported for asthma were the same in both systems (isocyanates, flour, and wood dust). 15% of the PROPULSE cases were not covered by the WCB, and therefore would not be found in the board's official statistics. CONCLUSIONS: A physician based reporting procedure can be implemented as part of a surveillance system to supplement data from other sources and thus provide a better understanding of the occurrence of occupational respiratory diseases. 相似文献
98.
F. Marino M. Cosentino F. De Ponti C. Giaroni L. Somaini R. Bombelli M. Ferrari A.J. Aasen S. Lecchini G. Frigo 《Autonomic & autacoid pharmacology》1997,17(6):365-372
1 The present study examined the role of muscarinic receptors in the modulation of noradrenaline (NA) release in the guinea-pig isolated distal colon. The spontaneous endogenous NA overflow assayed by HPLC-ED was taken as an index of NA release from enteric noradrenergic nerve terminals. 2 Physostigmine (10 μm ) significantly enhanced spontaneous endogenous NA overflow. Hyoscine (muscarinic antagonist), (R)-(-)-trihexyphenidyl and telenzepine (M1-selective antagonists), and 11[[2-[(diethylamino)methyl]-1-piperydil]acetyl]-5,11-dihydro-6H-pyrido[2,3-b][1,4]benzodiazepine-6-one (AF-DX 116, M2-selective antagonist) inhibited NA overflow in a concentration dependent manner, with the following EC50 values: 131.74 (18.19–953.96), 101.62 (58.83–175.60), 150 (60–330), 30 (5–170) nm , respectively. 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP, M1- and M3- selective antagonist) had no significant effect up to 100 μm . 3 The muscarinic agonist oxotremorine inhibited NA overflow in a concentration dependent manner, with an EC50 value of 0.67 (0.30–1.51) μm . The response to oxotremorine was inhibited by muscarinic antagonists with the following order of potency: hyoscine = (R)-(-)-trihexyphenidyl = telenzepine > 4-DAMP >> AF-DX 116. 4 In the presence of 3 μm tetrodotoxin (TTX), the effect of oxotremorine and 4-DAMP was unchanged, while hyoscine, (R)-(-)-trihexyphenidyl, telenzepine and AF-DX 116, instead of inhibiting, significantly enhanced NA overflow. 5 The present results indicate that, in the guinea-pig colon, endogenous acetylcholine sustains spontaneous NA release by activating muscarinic receptors possibly located on interneurones. In addition, inhibitory muscarinic receptors may exist on adrenergic terminals. 相似文献
99.
De Leo V; Morgante G; Lanzetta D; D'Antona D; Bertieri RS 《Human reproduction (Oxford, England)》1997,12(2):357-360
We report the results of administration of danazol after suspension of
gonadotrophin-releasing hormone analogue (GnRHa) therapy for uterine
myomas. A total of 21 women with uterine myomas was treated with 100 mg
danazol for 6 months after GnRHa therapy. Uterine volume and endocrine
status were monitored monthly by ultrasound and assay of plasma
gonadotrophins, oestradiol and progesterone. The results show a rebound of
uterine volume about 30% less than in controls at the end of danazol
therapy. Menstrual cyclicity returned after 65 +/- 3 days in 16 subjects
and five patients remained amenorrhoeic. Hormone assays confirmed renewed
ovarian function in the women whose menstrual periods returned. Bone
mineral content was substantially reduced during GnRHa treatment but
improved significantly during danazol therapy even in the women who
remained amenorrhoeic. These results show the utility of danazol in
prolonging the therapeutic effects of GnRHa. The mechanism by which danazol
inhibits rebound of uterine volume may be due to its antiprogesterone
effects on uterine myomas.
相似文献
100.
Hilda A. Perez Carmen Bracho Mirtha Romano Mercedes De la Rosa 《Parasitology research》1997,83(3):246-251
A monoclonal antibody raised by immunization of BALB/c mice with erythrocytic stages of Plasmodium vivax was shown to react with asexual erythrocytic stages of P. chabaudi. The cross-reactivity molecules are antigens of 200 and 148 kDa in P. vivax and of 190 and 70 kDa in P. chabaudi. Immunofluorescence studies of the erythrocytic stages of P. vivax and P. chabaudi indicated that expression of these antigens increased as the parasites' developed from the ring stage to the schizont stage.
In the mature trophozoites of P. chabaudi, immunoelectron microscopy revealed clusters of antigen distributed in the cytoplasm of the parasitized erythrocyte. In the
schizont, packets of antigen were found associated with the parasitophorous vacuole and the cytoplasm of the infected host
cell.
Received: 19 March 1996 / Accepted: 28 August 1996 相似文献