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81.
Isolation of a human cDNA for alpha 2-thiol proteinase inhibitor and its identity with low molecular weight kininogen 总被引:13,自引:0,他引:13
A lambda gt11 cDNA library containing DNA inserts prepared from human liver mRNA has been screened with an antibody to human alpha 2-thiol proteinase inhibitor that was isolated from fresh plasma. Eighteen positive clones were isolated from one million phage, and each was plaque purified. The cDNA insert of one of these phage was sequenced and shown to code for alpha 2-thiol proteinase inhibitor as identified by a partial amino acid sequence of the light chain of alpha 2-thiol proteinase inhibitor. This cDNA insert contained 1529 base pairs coding for the complete alpha 2-thiol proteinase inhibitor. It included 45 base pairs of 5' noncoding sequence, 1281 base pairs that code for pre alpha 2-thiol proteinase inhibitor, a stop codon, 160 base pairs of 3' noncoding sequence, and 40 base pairs of poly(A) tail. The noncoding sequence on the 3' end contained a potential recognition site (AATAAA) for processing and polyadenylation of precursor messenger RNA. The amino acid sequence of alpha 2-thiol proteinase inhibitor deduced from the cDNA showed a striking similarity (overall homology at 74%) to that of bovine low molecular weight (LMW) kininogen, including two internally repeated sequences and a nonapeptide sequence of bradykinin. These data clearly indicated that alpha 2-thiol proteinase inhibitor and LMW kininogen are identical. This was further supported by immunological cross-reactivity between alpha 2-thiol proteinase inhibitor and LMW kininogen.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
82.
We studied changes in both laryngeal resistance (Rla) and respiratory resistance (Rrs) after a voluntary deep breath in 7 normal and 20 asthmatic subjects. Rla was measured using a low-frequency sound method (Sekizawa et al. J. Appl. Physiol. 55: 591-597, 1983) and Rrs by forced oscillation at 3 Hz. In normal subjects, both Rla and Rrs significantly decreased after a voluntary deep breath (0.05 less than P less than 0.01). During methacholine provocation in the normal subjects, a voluntary deep breath significantly decreased Rrs (0.05 less than P less than 0.01, but Rla was significantly increased (0.05 less than P less than 0.01). In 10 asthmatic subjects in remission, a voluntary deep breath significantly increased Rrs (0.05 less than P less than 0.01) but significantly decreased Rla (0.05 less than P less than 0.01). In another 10 asthmatic subjects during spontaneous mild attacks, a voluntary deep breath significantly increased both Rrs and Rla (0.05 less than P less than 0.01). The present study showed that without obvious bronchoconstriction, Rla decreased after a voluntary deep breath in both normal and asthmatic subjects but, with bronchoconstriction, Rla increased in both groups. Subtraction of the change in Rla from Rrs gives the change in Rrs below the larynx (Rlow). Rlow changed little or decreased in normal subjects and increased in asthmatic subjects, irrespective of base-line bronchomotor tone. These results suggest that airway response below the larynx after a voluntary deep breath differentiates patients with bronchial asthma from normal subjects. 相似文献
83.
We exposed two awake dogs with a chronic tracheostomy and the cervical vagus nerves exteriorized in skin loops to 1.0 ppm of ozone (O3) for 2 h at intervals of 4 wk. We measured ventilatory variables before and after O3 exposure during rest and exercise before and after vagal block. We compared the effects of vagal blockade, exercise, and O3 on the primary determinants of breathing pattern (VT/TI, VT/TE, TI, and TE) in each of three conditions: base line (steady state), during hypercapnia, and after inhalation of 1% histamine. Under base-line conditions, O3 increased respiratory rate and decreased tidal volume (VT) by shortening time of expiration (TE) and time of inspiration (TI) without affecting VT/TI, an indicator of the neural drive to breathing. During progressive hypercapnia, O3 shortened TE and TI by effects both on tonic (nonvolume-related) and on phasic (volume-related) vagal inputs, and only the latter were prevented completely by cooling of the vagus nerves. Histamine-induced tachypnea was increased by O3 and was totally blocked by cooling the vagus nerves. We conclude that O3 shortens the timing of respiration without increasing ventilatory drive, shortens TI and TE through vagal and nonvagal pathways, increases tonic nonvagal and phasic vagal inputs, and stimulates more than one vagal fiber type. 相似文献
84.
Hemodynamics and vascular sensitivity to circulating norepinephrine in normal skin and delayed and acute random skin flaps in the pig 总被引:1,自引:0,他引:1
C Y Pang P C Neligan C R Forrest T Nakatsuka G H Sasaki 《Plastic and reconstructive surgery》1986,78(1):75-84
Cutaneous circulation in 4 X 10 cm skin samples and delayed and acute random skin flaps constructed on the flanks of castrated Yorkshire pigs (13.3 +/- 0.7 kg; n = 12) were studied during intravenous infusion (0.5 ml per minute) of 5% dextrose solution (vehicle) and 5% dextrose containing norepinephrine (1 microgram/kg per minute). Total and capillary blood flow and A-V shunt flow were measured by the radioactive microsphere technique 6 hours after the raising of 4 X 10 cm single-pedicle acute and delayed random skin flaps using the technique and calculations published previously. Fluorescein dye test was also performed to assess vascular perfusion. It was observed that the capillary blood flow in the single-pedicle delayed skin flaps was similar to that in the normal skin, and the maintenance of this normal skin blood flow was not due to the closing of A-V shunt flow in the delayed skin flaps. Similarly, the significant (p less than 0.01) decrease in capillary blood flow and distal perfusion in the acute skin flaps compared with the delayed skin flaps was not due to the opening of A-V shunts in the acute skin flaps. There was no evidence to indicate that A-V shunt flow per se was the primary factor for the regulation of capillary blood flow in the acute and delayed skin flaps in the pig. Our data seemed to indicate that tissue ischemia in the distal portion of acute skin flaps was likely the result of vasoconstriction of the small random arteries which supplied blood to arterioles and A-V shunts, and locally released neurohumoral substances may play an important role in the pathogenesis of vascular resistance and ischemia in the acute skin flaps. 相似文献
85.
Yutaka Tamaura Katsunobu Takahashi Yoh Kodera Yuji Saito Yuji Inada 《Biotechnology letters》1986,8(12):877-880
Summary A ferromagnetic modifier was prepared by reacting ferrous(Fe2+)- and ferric(Fe3+)-ions with polyethylene glycol having two carboxyl groups (MW:2000) at pH 8.0–8.5. Lipase fromPseudomonas
fragi 22–39B was coupled with the modifier using water-soluble carbodiimide. The modified lipase, which was dispersed into buffered solutions in the size range of 30–70 nm, exerted the hydrolytic activity of 8.0 U/mg. In a magnetic field of 250 Oe, the ferromagnetic-modified lipase was readily recovered from the colloidal solution. 相似文献
86.
Structure, expression, and chromosomal location of the human c-fgr gene. 总被引:22,自引:11,他引:11
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M Nishizawa K Semba M C Yoshida T Yamamoto M Sasaki K Toyoshima 《Molecular and cellular biology》1986,6(2):511-517
87.
Diazepam action onγ-aminobutyric acid-activated chloride currents in internally perfused frog sensory neurons 总被引:3,自引:0,他引:3
The Cl- current (ICl) in gamma-aminobutyric acid (GABA)-sensitive frog sensory neuron was separated from other Na+, Ca2+, and K+ currents using a suction pipette technique which allows internal perfusion under a single-electrode voltage clamp. Diazepam (DZP) itself evoked no response but facilitated the dose- and time-dependently GABA-induced ICl without changing the GABA equilibrium potential (EGABA) at concentrations ranging widely, from 3 X 10(-9) to 10(-4) M. In the presence of DZP, the GABA dose-response curve shifted to the left without changing the maximum current, indicating that DZP modifies the interaction between GABA and its receptor rather than affecting directly the channel activation step. The enhancement of the GABA-induced ICl by DZP depended neither on the membrane voltage nor on the inward or outward direction of the ICl. DZP also potentiated the ICl elicited by GABA agonists such as beta-alanine, taurine, homotaurine, 5-aminovaleric acid, l-GABOB, d-GABOB, glycine, and muscimol. The GABA response enhanced by pentobarbital (PB) was further enhanced by adding DZP, indicating that DZP and PB do not act in the same way. Ro5-3663, a diazepam analogue, enhanced the GABA-induced ICl only in a narrow range of the concentrations but inhibited the current at concentrations higher than 2 X 10(-6) M. 相似文献
88.
Summary Monoaminergic nerve fibers were studied in the pineal organ of the monkey, Macaca fuscata, by use of fluorescence and immunohistochemical procedures. Abundant formations of noradrenergic nerve fibers were observed in the pineal organ. They entered the parenchyma in the form of several coarse bundles via the capsule in the distal portion of the organ and spread throughout the organ after branching into smaller units. The density of the autonomic innervation decreased gradually toward the proximal portion of the organ. In the distal portion, numerous nerve fibers formed perivascular plexuses around the blood vessels and some fibers ran as bundles unrelated to the blood vessels in the stroma. Fine varicose fibers and bundles derived from these plexuses penetrated among the pinealocytes. However, only a few intraparenchymal fluorescent fibers were detected in the proximal third of the gland. With the use of serotonin antiserum serotonin-immunoreactive nerve fibers were clearly restricted to the ventroproximal part of the pineal organ. Although the somata of the pinealocytes showed intense immunoreactivity, their processes were not stained. In one exceptional case, clusters of pinealocytes displaying very intense immunoreactivity were found in an area extending from the distal margin of the ventral portion of the pineal stalk to the proximal portion of the pineal organ proper; these cells were bipolar or multipolar and endowed with well-stained processes. 相似文献
89.
Summary Skins from back and tail were dissected from tadpoles of Rana japonica prior to resorption of the tail and separated into epidermis and dermis by treatment with neutral protease. Homotypically and heterotypically recombined skins were constructed from the separated epidermis and dermis and transplanted into the tail of the original tadpole. Skin grafts using dermis from tail region degenerated simultaneously with resorption of the tail. However, skin grafts containing dermis from back region survived on the posterior part of the juvenile frog beyond metamorphosis. Furthermore, all epidermis underlaid with dermis from back region formed secretory glands and became flattened epithelia characteristic of adult back skin, regardless of region from which the epidermis came. Even when epidermis isolated from tail skin was cultured inside a back skin graft, the tail epidermis survived forming an epithelial cyst and developed secretory glands. These results suggest that regional specificities of anuran larval skin, i.e., development of back skin and even histolysis of tail skin, are determined by regionally specific dermis. The results also suggest that some of epidermal cells of tail skin are able to differentiate into epithelial cells similar to back skin of the adult under the influence of back dermis. 相似文献
90.
Akira Inokuchi Yasunobu Tomida Chizuko Yanaihara Ryogo Yui Yutaka Oomura Hiroshi Kimura Takanobu Hase Tomoaki Matsumoto Noboru Yanaihara 《Cell and tissue research》1986,246(1):71-75
Summary Immunohistochemically, nerve fibers and terminals reacting with anti-N-terminal-specific but not with anti-C-terminal-specific glucagon antiserum were observed in the following rat hypothalamic regions: paraventricular nucleus, supraoptic nucleus, anterior hypothalamus, arcuate nucleus, ventromedial hypothalamic nucleus and median eminence. Few fibers and terminals were demonstrated in the lateral hypothalamic area and dorsomedial hypothalamic nucleus. Radioimmunoassay data indicated that the concentration of gut glucagon-like immunoreactivity was higher in the ventromedial nucleus than in the lateral hypothalamic area. In food-deprived conditions, this concentration increased in both these parts. This was also verified in immunostained preparations in which a marked enhancement of gut glucagon-like immunoreactivity-containing fibers and terminals was observed in many hypothalamic regions. Several immunoreactive cell bodies were found in the ventromedial and arcuate nuclei of starved rats. Both biochemical and morphological data suggest that glucagon-related peptides may act as neurotransmitters or neuromodulators in the hypothalamus and may be involved in the central regulatory mechanism related to feeding behavior and energy metabolism. 相似文献