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81.
82.
We have studied five males with B?rjeson-Forssman-Lehmann syndrome (BFLS) from two unrelated families. They had a characteristic facial appearance with prominent supraorbital ridges, deep-set eyes, ptosis, and large ears, as well as obesity, severe mental retardation, hypotonia, and hypogonadism. Ophthalmologic, EEG, and skeletal abnormalities were also present. The findings in several presumed or possible heterozygous women were evaluated and suggested a wide range of phenotypic effects varying between apparent normality to mild or moderately evident BFLS manifestations. The observed pattern of occurrence of the BFLS in our two families provides strong support for X-linked inheritance. In clinically normal female relatives at risk for being carriers of BFLS, we have been unsuccessful in identifying a reliable screening test. The condition in our and previously reported patients was contrasted with other malformation syndromes and our findings support the conclusion that BFLS is a distinct and clinically identifiable disorder. 相似文献
83.
Y S Yeh Y Iriyama Y Matsuzawa S R Hanson H Yasuda 《Journal of biomedical materials research》1988,22(9):795-818
Tubular blood-contacting polymeric materials were modified by plasma polymerization and evaluated in the baboon with respect to their capacity to induce both acute and chronic arterial thrombosis. Polymer surface composition was determined by electron spectroscopy for chemical analysis. Steady-state arterial thromboembolism was initiated by introducing tubular segments into chronic arteriovenous shunts. Rates of platelet destruction induced by the test materials were calculated from 111In-platelet survival measurements. Nine plasma polymers based on tetrafluoroethylene, hexafluoroethane, hexafluoroethane/H2, and methane, when deposited on silicone rubber, consumed platelets at rates ranging from 1.1-5.6 x 10(8) platelets/cm2-day. Since these values were near the lower detection limit for this test system, the plasma polymers were considered relatively nonthrombogenic. Acute thrombus formation was initiated by inserting expanded Teflon (Gore-Tex PTFE) vascular grafts into the shunt system. 111In-platelet deposition was measured by scintillation camera imaging over a 1-h exposure period. Standard PTFE grafts (10 cm x 4 mm i.d.) accumulated approximately 1 x 10(10) platelets over this interval. While modification of PTFE grafts with a plasma polymer based on hexafluoroethane/H2 did not alter graft surface morphology, platelet deposition was reduced by 87% as compared to the controls (p less than 0.001). We conclude that both the surface chemistry and texture of prosthetic materials influence thrombogenesis. The method of plasma polymerization may be useful for assessing the importance of these variables independently and, perhaps, for minimizing certain adverse blood-material interactions. 相似文献
84.
Petit J Klam F Grantyn A Berthoz A 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1999,125(3):287-301
Pontine omnipause neurons (OPNs) have so far been considered as forming a homogeneous group of neurons whose tonic firing
stops during the duration of saccades, when the head is immobilized. In cats, they pause for the total duration of gaze shifts,
when the head is free to move. In the present study, carried out on alert cats with fixed heads, we present observations made
during self-initiated saccades and during tracking of a moving target which show that the OPN population is not homogeneous.
Of the 76 OPNs we identified, 39 were found to have characteristics similar to those of previously described neurons, ”saccade”
(S-) OPNs: (1) the durations of their pauses were significantly correlated with the durations of saccades; (2) the discharge
ceased shortly before saccade onset and resumed before saccade end; (3) visual responses to target motion were excitatory;
and (4) during tracking, S-OPNs interrupted the discharge for the duration of saccades and resumed firing during perisaccadic
”drifts”. However, the characteristics of 37 neurons (”complex” (C-) OPNs) were different: (1) the pause duration was not
correlated with the duration of self-initiated saccades; (2) time lead of pause onsets relative to saccades was, on average,
longer than in the group of S-OPNs, and firing resumed after the saccade end; (3) visual target motion suppressed tonic discharges;
and (4) during tracking, firing was interrupted for the total duration of gaze shifts, including not only saccades but also
perisaccadic ”drifts”. We conclude that cat OPNs can be subdivided into two main groups. The first comprises neurons whose
firing patterns are compatible with gating individual saccades (”saccade” OPNs). The second group consists of ”complex” OPNs
whose firing characteristics are appropriate to gate total gaze displacements rather than individual saccades. The function
of these neurons may be to disinhibit pontobulbar circuits participating in the generation of saccade sequences and associated
perisaccadic drifts.
Received: 20 January 1998 / Accepted: 22 October 1998 相似文献
85.
Bronchocentric granulomatosis: a complication of allergic bronchopulmonary aspergillosis. 总被引:1,自引:0,他引:1
G Hanson N Flor I Wells H Novey S Galant 《The Journal of allergy and clinical immunology》1977,59(1):83-90
Hypersensitivity to the fungal antigens of Aspergillus fumigatus may result in a spectrum of immune injury collectively known as allergic bronchopulmonary aspergillosis (ABPA). This report describes a 14-yr-old boy who presented clinical findings consistent with ABPA,including a history of asthma, blood eosinophilia, serum precipitins, and IgE antibodies to Aspergillus fumigatus. Sputum Aspergillus, pulmonary infiltrates, and dual types I and III skin reactions to Aspergillus fumigatus were observed also. Pathology of the resected right upper lobe revealed severe bronchial destruction with the findings of bronchocentric granulomatosis. Noninvasive septate fungal hyphae compatible with Aspergillus were identified. Cultures from sputum and surgical specimens grew Aspergillus and Mycobacterium intracellulare avium. The PPD-B (purified protein derivative-Batty) intradermal skin test produced a 6 mm induration (PPD-S was negative). The patient's condition has been well controlled with prednisone and several antituberculous drugs. In addition, inflammatory and immunologic parameters have begun to return to normal. The relationship between ABa and the atypical mycobacterial infection is not clear. The association of ABPA with the severe bronchial destruction seen in bronchocentric granulomatosis is emphasized to alert physicans to this serious sequelae of ABa seen in the asthmatic. 相似文献
86.
87.
88.
Ray L. Hanson Alan R. Dahl Simon J. Rothenberg Janet M. Benson Antone L. Brooks John S. Dutcher 《Archives of environmental contamination and toxicology》1985,14(3):289-297
Volatile components from diesel exhaust particles and coal gasifier process gas condensate were vacuum fractionated by cryogenic distillation and identified by infrared spectroscopy and gas chromatography/mass spectrometry. The vacuum distillation line consisted of a sample flask and nine traps cooled from 0°C to ?196°C in approximately 20°C steps. The pressure in the vacuum line of about 10?2 Torr was maintained with a vacuum pump. Separated compounds were identified by comparison to reference infrared spectra and confirmed by comparison with standards when practical. Volatile compounds identified from the diesel exhaust particle sample included NOx, carbon dioxide, sulfur dioxide, alkanes, aldehydes, and one and two ring aromatic hydrocarbons. Volatile compounds identified in process gas condensate from a coal gasifier were ammonia, carbonyl sulfide, carbon dioxide, C3-C7 hydrocarbons, one and two ring aromatic hydrocarbons, and phenols. Volatile components collected at either 0° or ?24°C were evaluated to determine their genotoxicity using the Chinese hamster ovary/hypoxanthine-guanine phosphoribosyltransferase (CHO/HGPRT) assay. Neither the gasifier condensate nor diesel particle samples produced mutations at the HGPRT locus. The diesel samples were not cytotoxic at the concentrations tested (100 μg/ml) but the gasifier samples resulted in 50% cell killing at concentrations between 25 and 100 μg/ml depending on the temperature of collection and the test conditions. Vacuum desorption with cryogenic distillation has provided a means to separate the volatile components in complex environmental samples to allow chemical and biological characterization of these components. 相似文献
89.
Hanson BG 《Sociology of health & illness》1985,7(1):21-35
This paper examines the dynamics of the process of negotiation in a nursing home by focusing on the process of gaining advantage. The concepts of primary and secondary advantage are introduced in order to allow comparison and organization of the data. In the course of examining what rewards are possible and how they are achieved, we are able to see that the impetus to treat and the control of treatment action often lies with the staff of the home rather than the physician, that officially imposed definitions may be unfavourable to the persons they are imposed upon and that the process of deciding on everyday activities is often complex. 相似文献
90.
Summary Thirty-two patients with common variable immunodeficiency (CVID) and two patients with IgA and IgG subclass deficiency received a total of 1,040 intravenous (i.v.) infusions during 60 patient years with 7,575 g of a new immunoglobulin (Ig) preparation. The content of prekallikrein activators and the anti-complementary activity in the tested Ig preparation was low and, in comparison to seven other commercial i.v. Igs, so was the proportion of IgG polymers and fragments. The IgA content was always 0.02 g/l, often <0.004 g/l, and it was possible to continuously give the Ig prophylactically to four patients with anti-IgA antibodies, i.e. three with CVID and one with combined IgA-IgG2 deficiency. Adverse reactions were only noted in 4.7% of the 1,040 infusions and in 12 out of the 34 patients. None of the reactions were of the anaphylactic type, but two patients had moderate reactions and one had anuria, probably not caused by the Ig. A simultaneous infection seemed to increase the risk of phlogistic reactions, as five out of six patients who reacted with temperature rise and chills had a simultaneous upper respiratory tract infection. A substudy of various dosage schedules was performed with 11 patients receiving 203 infusions over 10.8 patient years. On 25 mg/kg/week of Ig given i.v. every five weeks, a mean increase in the preinfusion serum IgG level of 0.3 g/l was observed, as compared to earlier i.m. prophylaxis with the same dose. Only 1/4 of the patients on 25 mg/kg/week every five or three weeks reached a preinfusion IgG level 3 g/l. On 50 mg/kg/week every two weeks, 4/4 CVID patients had preinfusion levels above 3 g/l with a mean preinfusion increase of 1.5 g/l over the start level. Finally, 100 mg/kg/week every three weeks gave 5/5 patients a preinfusion serum IgG level of >4 g/l with a mean rise of 3.6 g/l, as compared with the levels before the study. An association between decreasing preinfusion IgG serum levels and the presence of infection was noted on 13/17 occasions, while increasing IgG was seen in healthy periods on 14/14 observations.
1040 Infusionen mit einem nicht modifizierten Immunglobulin-Produkt, das bei Patienten mit Antikörpermangelsyndrom wenig Nebenwirkungen hervorruft
Zusammenfassung 32 Patienten mit gewöhnlichem variablen Immunglobulinmangel (CVID) und zwei Patienten mit fehlenden IgA- und IgG-Subklassen erhielten zusammen 1040 intravenöse (i.v.) Infusionen innerhalb von 60 Patientenjahren mit 7575 g einer neuen Immunglobulinpräparation (Ig). Der Gehalt an Prä-Kallikrein-Aktivatoren und die anti-komplementäre Aktivität in der getesteten Ig-Präparation war gering, verglichen mit sieben anderen kommerziell erhältlichen i.v. Immunglobulinen. Dasselbe gilt für den Anteil an IgG-Polymeren und -Fragmenten. Der IgA-Gehalt betrug immer 0,02 g/l, oft 0,004 g/l. Das Ig konnte vier Patienten mit IgA-Antikörpern, d. h. drei mit CVID und einem mit kombiniertem IgA-IgG-Mangel kontinuierlich verabreicht werden. Nur bei 4,7% der 1040 Infusionen und bei 12 der 34 Patienten wurden Nebenwirkungen beobachtet. Keine der Nebenwirkungen war vom anaphylaktischen Typ, aber zwei Patienten hatten mittelschwere Nebenwirkungen und einer eine Anurie, die wahrscheinlich nicht durch das Ig verursacht war. Das Risiko für phlogistische Reaktionen schien durch gleichzeitige Infektionen erhöht zu werden. Dies wurde bei fünf von sechs Patienten beobachtet, die bei Infektion der oberen Atemwege auf die Infusion mit Temperaturanstieg und Schüttelfrost reagierten. Bei 11 Patienten, die über 10,8 Patientenjahre 203 Infusionen erhielten, wurde eine Sonderstudie zu verschiedenen Dosierungen durchgeführt. Bei Infusion von 25 mg/kg/Woche i.v. alle fünf Wochen wurde ein mittlerer Anstieg der Serumspiegel vor Infusion gemessen, der um 0,3 g/l höher war als bei früherer i.m. Prophylaxe mit derselben Dosis. Nur bei 1/4 Patienten, die alle fünf oder drei Wochen 25 mg/kg/Woche erhielten, wurde ein IgG-Spiegel vor Infusion von 3 g/l erreicht. Bei Gabe von 50 mg/kg/Woche alle zwei Wochen hatten 4/4 CVID-Patienten vor Infusion Spiegel über 3 g/l, dabei stiegen die Spiegel vor Infusion um 1,5 g/l höher an als vor Therapiebeginn. Bei 100 mg/kg/Woche alle drei Wochen wiesen 5/5 Patienten ein Serum IgG von >4 g/l auf; der mittlere Anstieg gegenüber den Werten vor Studienbeginn betrug 3,6 g/l. Bei 13/17 Fällen wurde eine Assoziation von abnehmenden IgG-Serumspiegeln vor Infusion mit einer Infektion beobachtet; in gesunden Phasen waren bei 14/14 Beobachtungen Anstiege der IgG-Spiegel zu beobachten.相似文献