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The major growth factors in bovine colostrum are transforming growth factor-beta s (TGF-beta 1 and TGF-beta 2) and insulin-like growth factors (IGF-1 and IGF-2). Recently, TGF-beta 2 content of bovine colostrum was measured using a TGF-beta 2 specific ELISA (1) and now we have validated ELISAs for for bovine TGF-beta 1 and IGF-1. The concentrations of IGF-1 and TGF-beta 1 in the first milking after calving were 248-1850 ng/ml and 12.4-42.6 ng/ml, respectively, and they declined in correlation with total protein concentration to 27.0-101 ng/ml (IGF-1) and 0.80-3.49 ng/ml(TGF-beta 1) by the fifth milkings. The amount of TGF-beta 1 was on average 5.3 +/- 1.4% of that of TGF-beta 2 and there is a high correlation (r = 0.966) between the concentrations of these growth factors in the same samples. No free TGF-beta 1 form of could be detected.  相似文献   

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The use of a collagen gel as a hard tissue induction material in fractured and undeveloped teeth is reviewed. Three of four cases demonstrate a modest amount of hard tissue formation within the pulp space previously occupied by the collagen gel. Limitations in positive results, compared with a previous animal study and one clinical case report, are probably due to the pre-existence of infection in the present study.  相似文献   

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Metal binding strategies employing low molecular weight chelators and equilibrium dialysis were used to investigate several unresolved aspects of zinc and copper binding to serum albumin. Direct measurement of histidine binding to bovine serum albumin when the histidine is presented either as a metal-chelate or alone provides no evidence for an albumin-metal-histidine ternary complex. Using previously determined intrinsic constants for Zn(II) and Cu(II), we have measured zinc binding to bovine serum albumin in the presence of saturating amounts of copper. The results of these experiments unambiguously show that zinc and copper bind at separate noninteracting sites on this protein. The intrinsic constants for zinc and copper binding to dog serum albumin have been determined. Contrary to previous reports, we find that dog serum albumin has a specific high affinity site for copper, log10K 10.17 for Cu(II) compared to 6.85 for Zn(II) at the separate site.  相似文献   

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A comparative study on extraction of Fe(III) from the HCl leach liquor of low grade iron ore tailings has been carried out using Tri-n-butyl phosphate (TBP), Cyanex 921 and Cyanex 923 in distilled kerosene. The percentage extraction of iron increased with increasing HCl and extractant concentrations. The extracted species in each case was found to be HFeCl4·S. The extraction isotherms for the above extractants indicated quantitative extraction of Fe(III) in 3-stages at O:A ratio of 3:2 with TBP, and in 2-stages at O:A ratio of 1:1 with Cyanex 921 and Cyanex 923. The stripping studies of the loaded organic phases were carried out with 0.4 M HCl. The stripping isotherms indicated 2-stages at O:A ratio of 5:2 for TBP, and 3-stages at O:A ratio of 2:3 for Cyanex 921 and Cyanex 923. From the extraction studies, the extraction efficiency of the extractants for Fe(III) was in the order TBP < Cyanex 921 < Cyanex 923. Although Cyanex 923 was found to be the best extractant, the percentage stripping of Fe from the loaded Cyanex 923 was the least. The stripping of Cyanex 923 was 94.9%, but with TBP and Cyanex 921, it was 99.8% and > 99.9%, respectively.  相似文献   

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This study compared the ability of three types of engine driven instrumentation techniques to negotiate and prepare small, slightly curved root canals. Forty five mesial roots of extracted maxillary and mandibular first permanent molars were classified into three groups. Group (I) was prepared by Canal Leader system, group (II) was prepared by Nickel Titanium files and group (III) was prepared by Canal Master technique. Radiographs of the root canal space before and after preparation was carried out by the aid of an experimental model. Enlarged photographic prints obtained from radiographs were scored for shaping effectiveness of the three techniques in respect to canal course, position & width of apical constriction and lack of ledge formation. The results indicated that the Canal Leader system was an efficient technique in maintaining canal curvature, absence of zipping, transportation or ledge formation in almost all of the specimen tested, followed by the Nickel Titanium files and then the Canal Master technique which produced more straightening and destruction of apical constriction.  相似文献   

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The increased incidence of drowsiness in hypoalbuminemic patients administered diazepam and more rapid clearance of tolbutamide in cirrhotics may be due to changes in plasma protein binding. The binding of diazepam and tolbutamide was studied by equilibrium dialysis at 37degreesC over a total drug concentration range of 1 to 10 mug/ml and 50 to 300 mug/ml, respectively, in plasma from 21 normal and 14 alcoholic subjects. At 1 mug/ml, diazepam plasma protein binding (+/- S.D.) was 98.5+/-0.4 per cent in normals and 97.8+/-1.2 per cent in alcoholics; at 100 mug/ml, tolbutamide binding was 97.8+/-0.3 per cent in normals and 95.1+/-4.2 per cent in alcoholics. For both agents at all concentrations, the binding to plasma from alcoholics was significantly decreased (P less than 0.01-less than 0.02). The extent of binding of both drugs was dependent on the albumin concentration. These findings suggest that important changes in pharmacologic effect, distribution, and clearance of diazepam and tolbutamide can be anticipated in alcoholics with hypoalbuminemia.  相似文献   

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BACKGROUND: The course of neurosyphilis has been reported to be altered by human immunodeficiency virus (HIV) infection. Prior reports of neurosyphilis occurring in association with HIV infection have been largely anecdotal and have failed to compare neurosyphilis in patients with HIV infection with an uninfected control group. This study was performed to determine if the clinical presentation encountered is different in the presence of HIV infection. DESIGN: A retrospective, hospital-based, case series study based on chart review encompassing a 64-month period. SETTING: The study was performed in a large, university-affiliated, public health trust hospital in south Florida. PATIENTS: Forty-six hospitalized patients with neurosyphilis were identified; 13 patients fulfilled Centers for Disease Control and Prevention (Atlanta, Ga) criteria for acquired immunodeficiency syndrome (AIDS), 11 were HIV seropositive only, and 22 were HIV uninfected. Neurosyphilis was determined by a reactive cerebrospinal fluid VDRL slide test. RESULTS: The HIV-infected patients (both AIDS and HIV-seropositive groups) were younger and more frequently had features of secondary syphilis, such as rash, fever, adenopathy, headache, or meningismus. Significant differences were observed in cerebrospinal fluid measurements when the HIV-infected group was compared with the HIV-uninfected group, including a higher mean white blood cell count in patients with AIDS and a higher mean protein level and a lower mean glucose level in the HIV-infected group. Syphilitic meningitis was more common in HIV-seropositive patients, although the HIV-uninfected patients presented with a greater variety of types of neurosyphilis. Ophthalmic syphilis was observed more frequently in the HIV-infected group. CONCLUSIONS: Significant differences exist between neurosyphilis occurring in the presence and absence of HIV infection.  相似文献   

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In order to evaluate the efficacy of centrally acting analgesics. In treating rheumatic diseases, tramadol hydrochloride (Tramal Grunental) has been administered to a group of 68 patients (36 women and 32 men), who received 100 mg twice a day during a 10-day treatment. The testing comprised 14 female patients with rheumatoid arthritis, 20 patients (7 women and 13 men) with degenerative (OA) hip and knee diseases and 34 patients (15 women and 19 men) affected by the vertebrogen painful syndrome of lumbar spine. The control group comprised 12 patients (9 women and 3 men) with rheumatoid arthritis using non-steroidal antiinflammatory drugs only, 22 patients (12 women and 10 men) with the OA of the hip and knee, using paracetamol only, and 30 patients (15 women and 15 men) affected by the vertebrogen painful syndrome of lumbar spine, also using paracetamol only. The visual analogue scale has been used in following the pain relief assessments during the therapy. It has thus been observed that the intensity of pain has not been significantly relieved with the acute rheumatic diseases (p > 0.05) in the control group either; that the significant pain relief has occurred with the degenerative (OA) rheumatic diseases (p < 0.05) but not in the control group; while the best analgetic effect of tramadol has been proved on the patients affected by the vertebrogen painful syndrome of lumbar spine (p < 0.01) but was not significant in the control group. During the therapeutic treatment 13 patients (19%), mostly the elderly, experienced side effects, manifested as nausea and the dry mouth.  相似文献   

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We have compared the value of immunohistochemical and polymerase chain reaction (PCR) techniques in distinguishing follicular lymphoma from follicular hyperplasia in formalin-fixed paraffin-embedded tissues of 41 follicular lymphomas, 15 reactive lymph nodes and 5 reactive tonsils. Immunohistochemistry demonstrated bcl-2 protein in the follicle centre cells of 97% of follicular lymphomas whereas monoclonal immunoglobulin light chain was detected in 83% of cases. Assessing the lowest proliferating follicle of each case by MIB-1 immunostaining, proliferation fractions in the lymphomas varied from 0.5% to 59% (mean 15.6%). Over 80% of lymphomas had proliferation fractions of less than 25%. PCR detected gene rearrangement either at the bcl-2 locus, or at the IgH locus, or at both loci in 32%, 44% and 61% of lymphomas, respectively. The follicle centre cells of the reactive lymph nodes and tonsils were all bcl-2 protein negative and polytypic for kappa and lambda light chains. Proliferation fractions of the lowest proliferating follicle in each reactive case ranged from 30.5% to 86.8% (mean 64.9%). Rearrangements of the bcl-2 or IgH loci were not detected in any reactive case. This study demonstrates that bcl-2 and light chain immunostaining are the most consistently helpful aids to diagnosing follicular lymphoma. A low proliferation fraction also indicates lymphoma but a high proliferation fraction does not exclude the diagnosis. Immunostaining with a combination of anti bcl-2 and MIB 1 antibodies is a sensitive and specific method for identifying follicular lymphoma, is technically simple to perform and easy to interpret. In occasional cases, where immunostaining gives equivocal results, PCR analysis can confirm lymphoma, but a negative result does not exclude the diagnosis.  相似文献   

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Several new, non-benzodiazepine hypnotic drugs have recently been marketed (zopiclone, zolpidem) or are in development (zaleplon, SX 3228). These compounds act at benzodiazepine (BZ) (omega) receptors but have mechanisms of action which are not identical to those of benzodiazepines; in particular, zolpidem, zaleplon and SX 3228 have been reported to have selectivity for the BZ1 (omega 1) receptor subtype. In the present study the effects of the four hypnotic drugs were investigated in rats trained to discriminate ethanol (1 g/kg). Comparisons were made with pentobarbital and the benzodiazepines, lorazepam and midazolam. The two benzodiazepines and the barbiturate produced dose-related substitution for ethanol. In contrast, zolpidem, zaleplon, SX 3228 and zopiclone gave rise to only partial (maximum effect 50-67%) substitution, even at doses which greatly reduced rates of lever pressing. The limited ethanol-like effects of zolpidem, zaleplon and SX 3228 may be related to the more selective mechanism of action of these compounds. It is not clear why the effects of zopiclone differed from those of the benzodiazepines.  相似文献   

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(BACKGROUND): Surgical therapy for Benign Prostatic Hypertrophy (B.P.H.) has mainly depended upon Transurethral Resection of the Prostate (TUR-P) using a cutting loop electrode. Recently, a new technique TVP was reported using the VaporTrode apparatus. We assessed the safety and efficacy of the VaporTrode in a preliminary study. (METHODS): Histological changes of the muscle and liver of pigs were examined after vaporization using the VaporTrode and a cutting loop electrode. First, histological changes were investigated following vaporization after one stroke at a slow hand speed. Next, histological changes were assessed following vaporization at fixed stroke speed in an experimental model. (RESULTS): At an electrical output of less than 275 W, the depth of the vaporized layer increased as the stroke speed became slower (4.0 cm/s-2.5 cm/s). When the electrical output was 300 W, the depth of vaporized layer increased even at a faster stroke speed (2.5 cm/s-3.0 cm/s.) The depth of the desiccated layer increased as the stroke speed became slower at any electrical output. However, when the stroke speed was 4.0 cm/s, the depth of this layer was less than 2.0 mm. With the cutting loop electrode, the depth of the desiccated layer increased at a higher electrical power, but the change was very small. (CONCLUSION): To achieve deep enough vaporized and desiccated layers safely, the VaporTrode should be used at a stroke speed slower than 3.0 cm/s and a high electrical power of about 275 W.  相似文献   

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In this paper we describe a two-dimensional gel database of the regenerating newt limb. Protein synthesis was compared in the intact limb, in the 1-week regenerating limb, representing the dedifferentiation stage, and in the 2-week regenerating limb, representing the formation of the blastema. This comparative database provided data on differential expression of about 800 proteins during the process of limb regeneration. In addition, a map has been generated for these proteins for future guidance in characterizing further new, unknown proteins. The overall expression patterns of the proteins indicated that the dedifferentiation stage was marked by down-regulation of most proteins, while the blastema formation was marked by the appearance of many new proteins. The potential use of such a database in isolating factors involved during limb regeneration is discussed.  相似文献   

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Differing reports in the literature on the intellectual capabilities of patients with unspecific ulcerative colitis caused us to undertake a controlled test-psychological study. 30 patients with ulcerative colitis and 30 "healthy" control persons were tested with the Hamburg-Wechsler-Intelligenztest für Erwachsene (HAWIE). The patients and the controls were matched as regards age, sex, family status, education, professional status and monthly income. A statistical comparison using the Wilcoxon matched-pairs signed-ranks test showed that the two groups did not differ significantly in their intelligence quotients. Our results seem to indicate that the assumption of extraordinary intellectual capabilities of patients with ulcerative colitis is not tenable.  相似文献   

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