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21.
Inbred rabbits of B/Jas strain were found to be highly susceptible to herpes simplex virus type 1 encephalitis, following i.v. injection of the virus, while Chbb:HM strain rabbits were not susceptible. The susceptibility trait seemed to be inherited recessively, involving multiple genes, because (B/Jas x Chbb:HM)Fl hybrids were as resistant as Chbb:HM rabbits, and because more than 90% of backcrosses of (B/Jas x Chbb: HM)FI to B/Jas were resistant to viral inoculation. The encephalitis in B/Jas rabbits resembled human herpes simplex encephalitis, in that the temporal lobe as well as the brain stem were affected preferentially, leading to the development of various types of seizures, such as circling, loss of balance leading to a fall, and tonic and clonic convulsions. The disease could be diagnosed by magnetic resonance imaging (MRI) analysis before onset of seizures, and diseased rabbits showed a marked lymphopenia at onset of seizures. © 1995 Wiley-Liss, Inc.  相似文献   
22.
The objective of this study was to demonstrate the appearance of ampullary carcinoma using current MR techniques, including fat suppression, gadolinium enhancement, and MR cholangiography. Nine patients with ampullary carcinoma were examined by MRI at 1.5 T. MR examinations included T1-weighted spoiled gradient echo, T1-weighted fat-suppressed, and immediate postgadolinium spoiled gradient echo images for all patients and MR cholangiography for three patients. The imaging features of ampullary carcinomas, including tumor size and morphology, signal intensity, and enhancement characteristics, were determined. Ampullary carcinomas shown on MR images ranged in size from 1.5 to 5.5 cm. Tumors were low in signal intensity on precontrast T1-weighted spoiled gradient echo and T1-weighted fat-suppressed images relative to normal pancreatic tissue and enhanced less than normal pancreas on immediate postgadolinium spoiled gradient echo images. Tumor conspicuity was greatest on immediate postgadolinium spoiled gradient echo images. MR cholangiography demonstrated high grade obstruction of the common bile duct and mild dilatation of the pancreatic duct at the level of the ampulla with abrupt termination of the ducts in two untreated patients and moderate dilatation of the common bile duct in one patient who had a biliary stent. Ampullary carcinomas can be demonstrated on MR images as small masses arising at the ampulla. Tumors are well defined on immediate postgadolinium spoiled gradient echo images.  相似文献   
23.
C Shimomura  K Eguchi  A Kurata  M Seto  G Mameya  S Nagataki 《Ryūmachi》1991,31(5):519-27; discussion 525-6
We recently saw a patient who had aortitis syndrome associated with secondary amyloidosis. To our knowledge, she is the fourth report of this complication occurring in aortitis syndrome. In November 1985, the patient, a 18 year-old woman, was admitted to our hospital because of a high fever, back pain, abdominal pain and general fatigue. On physical examination, bruit was audible on the abdomen, bilateral radial artery was weakly palpable. Angiography showed the stenosis of bilateral carotid artery, subclavian artery, renal artery and superior mesenteric artery. From the above findings, she was diagnosed aortitis syndrome, and treatment was begun with prednisolone. However, she developed recurrently a high fever, chest pain, abdominal pain and exertional dyspnea. Laboratory findings at the active stage revealed the marked elevation of leukocytes, erythrocyte sedimentation rate and C-reactive protein. On her clinical course, the number of circulating thrombocytes was paralleled with the activity of the disease. On June 1988, she developed suddenly a high fever and severe pain of abdomen. Pathological findings of her stomach showed the deposition of amyloid protein A. Laboratory findings depicted the marked increment of thrombocytes, beta-thromboglobulin and platelet factor 4. These results suggest that circulating thrombocytes may play a role in product ion of amyloid protein.  相似文献   
24.
25.
Abstract  The general expectation that patients should be willing to trust nurses is rarely explored or challenged despite claims of diminishing public trust in social and professional institutions. Everyday meanings of trust take account of circumstance and suggest that our understanding of what it means to trust is contextually bound. However, in the context of health care, to trust implies a particular understanding which becomes apparent when abuses of this trust are reported and acknowledged as scandals. The predominant assumption in the literature that trust is something that occurs between equally competent adults cannot explain trust in nursing precisely because of the unequal power relationships between patients on the one hand and healthcare professionals on the other. Moreover, the tendency to conflate terms such as trust, reliance, confidence and so on suggests that confusion permeates discussions of trust in nursing. In this paper, I argue in support of Annette Baier's requirement of good will (or lack of ill will) as the essential feature of trust, and outline how this account (i) enables us to make the necessary distinctions between trust on the one hand and 'trust pretenders' on the other; and (ii) lays the foundations for understanding trust in relationships, such as those between patients and nurses, where power differentials exist.  相似文献   
26.
We describe the synthesis and some pharmacological properties of 16 new in vivo antagonists of oxytocin. These are based on modifications of three peptides: A, B, and C. A is our previously reported potent and selective antagonist of the vasopressor (V1 receptor) responses to arginine-vasopressin (AVP)/weak oxytocin antagonist, [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid), 2-O-methyltyrosine]arginine-vasopressin (d(CH2)5[Tyr(Me)2]AVP. B reported here, the Ile3 analogue of A, is d(CH2)5[Tyr(Me)2]AVT (5 below) and C is our previously reported potent nonselective oxytocin antagonist/AVP V1 antagonist, [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid),2-O- methyltyrosine,8-ornithine]vasotocin (d(CH2)5[Tyr(Me)2]OVT). The following substitutions and deletions, alone or in combination, were employed in A, B, and C: 1-deaminopenicillamine (dP); D-Tyr(Alk)2 (where Alk = Me or Et), D-Phe2; Val4, Thr4; delta 3-Pro7; Lys8, Cit8; desGly9, desGly-NH2(9), Ala-NH2(9); Leu-NH2(9); Arg-NH2(9). The 16 new analogues are (1) d(CH2)5[D-Tyr(Me)2]AVP, (2) d(CH2)5[D-Tyr(Me)2, Val4,delta 3-Pro7]AVP, (3) d(CH2)5[D-Tyr-(Et)2, Val4,Lys8]VP, (4) d(CH2)5[D-Tyr(Et)2,Val4,Cit8]VP, (5) d(CH2)5[Tyr(Me)2]AVT, (6) d(CH2)5[Tyr(Me)2,Lys8]VT, (7) dP[Tyr(Me)2]AVT, (8) dP[Tyr(Me)2,Val4]AVT, (9) d(CH2)5[D-Tyr(Me)2, Val4]AVT, (10) d(CH2)5[D-Phe2,Val4]AVT, (11) d(CH2)5[Tyr(Me)2,Thr4]OVT, (12) d(CH2)5[Tyr(Me)2,Thr4,Ala-NH2(9)]OVT, (13) d(CH2)5[Tyr(Me)2,Thr4,Leu-NH2(9)]OVT, (14) d(CH2)5[Tyr(Me)2,Thr4,Arg-NH2(9)]OVT, (15) desGly-NH2(9),d(CH2)5[Tyr(Me)2,Thr4]OVT, (16) desGly9,d(CH2)5[Tyr(Me)2,Thr4]OVT. 1-4 are analogues of A, 5-10 are analogues of B, and 11-16 are analogues of C. Their protected precursors were synthesized either entirely by the solid-phase method or by a combination of solid-phase and solution methods (1 + 8 or 8 + 1 couplings). All analogues were tested in rats for agonistic and antagonistic activities in oxytocic (in vitro, without and with Mg2+, and in vivo) assays as well as by antidiuretic and vasopressor assays. All analogues exhibit potent oxytocic antagonism in vitro and in vivo. With an in vitro pA2 (in the absence of Mg2+) = 9.12 +/- 0.09, dP[Tyr(Me)2]AVT is (7) one of the most potent in vitro oxytocin antagonists reported to date. Fifteen of these analogues (all but 6) appear as potent or more potent in vivo oxytocin antagonists than C (pA2 = 7.37 +/- 0.17). Analogues 1-9 and 14 are potent AVP V1 antagonists. Their anti-V1 pA2 values range from 7.92 to 8.45. They are thus nonselective oxytocin antagonists.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
27.
28.
M Abe  N Ono  K Tominaga  H Hojo  M Seto  S Fukuhara  H Wakasa 《Cancer》1992,70(4):821-829
Immunohistochemical and molecular genetic (bcl-2 gene) studies were performed on specimens from 24 patients with follicular small cleaved cell lymphoma (FSCCL), 24 patients with diffuse small cleaved cell lymphoma (DSCCL) and 4 patients with mantle zone lymphoma (MZL) to determine the cellular origin of the disease and whether or not DSCCL represents the diffuse counterpart of FSCCL. Two patients with FSCCL, 22 patients with DSCCL, and all of the patients with MZL had a phenotype of mantle zone (MZ) B-lymphocytes (SIgD+, Leu-1+, Leu-8+, positive alkaline phosphatase [ALPase+], and negative common acute lymphoblastic leukemia antigen [CALLA-]), and all the tested patients (2 patients with FSCCL, 13 patients with DSCCL, and 4 patients with MZL) had germlines of bcl-2 gene. Fourteen patients with FSCCL and 1 patient with DSCCL had a phenotype of follicular center cells (FCC) (CALLA+, SIgD-, Leu-1-, Leu-8- and negative ALPase), and 11 patients with FSCCL had bcl-2 gene rearrangements. These results indicate that FSCCL are almost always derived from FCC, whereas some FSCCL, most DSCCL, and all MZL are derived from MZ B-lymphocytes, and these lymphomas should be included in the same category as MZ B-lymphocyte-derived lymphomas. Histologically diagnosed DSCCL often may represent a diffuse counterpart of MZ B-lymphocyte-derived lymphoma. MZ B-lymphocyte-derived lymphomas histologically show a follicular (nodular), a follicular MZ, or a diffuse growth pattern and clinically show a high incidence of peripheral blood (PB) involvement or bone marrow (BM) involvement.  相似文献   
29.
Significant advances in understanding of P2X purinoceptor pharmacology have been made in the last few years. The limitations of nucleotide agonists as drug tools have now been amply demonstrated. Fortunately, inhibitors of the degrading ecto-ATPase enzymes are becoming available and it has become apparent that the complete removal of all divalent cations can be used experimentally in some systems to prevent nucleotide breakdown. Despite these issues, convincing evidence for P2X receptor heterogeneity, from data with agonists, has recently been reported.A number of new antagonists at P2X purinoceptors have also recently been described which to some degree appear to be more specific and useful than earlier antagonists like suramin. It is now apparent that suramin is a poor antagonist of ATP in many tissues because it potently inhibits ATPase activity at similar concentrations to those at which it blocks the P2X purinoceptor.Advances in the use of radiolabelled nucleotides as radioligands for binding studies has allowed the demonstration of P2X purinoceptors in a variety of tissues throughout the body including the brain. These studies have also provided evidence for receptor heterogeneity. Excitingly, two P2X purinoceptor genes have been cloned but operational studies suggest that more than two types exist. The cloning studies have also demonstrated a unique structure for the P2X purinoceptor which differentiates it from all other ligand-gated ion channel receptors. Further studies on P2X purinoceptor operation and structure are needed to help resolve controversies alluded to regarding the characterization and classification of nucleotide receptors. Hopefully such studies will also lead to a better understanding of the physiological and pathological importance of ATP and its activation of P2X purinoceptors. This will require the identification of better drug tools, in particular antagonists which may also provide the basis for novel therapeutic agents.  相似文献   
30.
Background: The objective of this study was to identify the extent to which propofol alters intracellular free Ca2+ concentration ([Ca2+]i), myofilament Ca2+ sensitivity, and contraction of individual cardiomyocytes during activation of [alpha]1a adrenoreceptors and to determine the cellular mechanism of action.

Methods: Freshly isolated ventricular myocytes were obtained from adult rat hearts. Myocyte shortening and [Ca2+]i were simultaneously monitored in individual cardiomyocytes exposed to phenylephrine after treatment with chloroethylclonidine ([alpha]1b-adrenoreceptor antagonist) and BMY 7378 ([alpha]1d-adrenoreceptor antagonist). Data are reported as mean +/- SD.

Results: Phenylephrine increased myocyte shortening by 124 +/- 9% (P = 0.002), whereas peak [Ca2+]i only increased by 8 +/- 3% (P = 0.110). Inhibition of phospholipase A2 and phospholipase C attenuated the phenylephrine-induced increase in shortening by 84 +/- 11% (P = 0.004) and 15 +/- 6% (P = 0.010), respectively. Inhibition of protein kinase C (PKC) and Rho kinase attenuated the phenylephrine-induced increase in shortening by 17 +/- 8% (P = 0.010) and 74 +/- 13% (P = 0.006), respectively. In the presence of phenylephrine, propofol increased shortening by 40 +/- 6% (P = 0.002), with no concomitant increase in [Ca2+]i. PKC inhibition prevented the propofol-induced increase in shortening. Selective inhibition of PKC[alpha], PKC[delta], PKC[varepsilon], and PKC[zeta] reduced the propofol-induced increase in shortening by 12 +/- 5% (P = 0.011), 36 +/- 8% (P = 0.001), 32 +/- 9% (P = 0.007), and 19 +/- 5% (P = 0.008), respectively. Na+-H+ exchange inhibition reduced the propofol-induced increase in shortening by 56 +/- 7% (P = 0.001).  相似文献   

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