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71.
The purpose of this study was to determine whether alcoholics with a co-existing anxiety disorder (dual-diagnosed group) experienced different withdrawal symptomatology from alcoholics without an anxiety disorder (alcohol-only group). Symptoms of alcohol withdrawal were measured on admission to an in-patient treatment program and throughout treatment (days 0, 2, 7, 14 and 21) using the revised Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar) scale. The dual-diagnosed group exhibited more severe alcohol withdrawal, as indicated by higher total CIWA-Ar scores, at all time points than the alcohol-only group. The possibility that anxiety disorders and alcohol withdrawal share a common neurochemical basis and that the CIWA-Ar scale may be useful as a screening instrument for anxiety disorders in alcoholics is discussed.  相似文献   
72.
Origin of Pulmonary Megakaryocytes   总被引:2,自引:0,他引:2  
1. Evidence is presented which indicates that pulmonary megakaryocytesdo not originate in the lungs but elsewhere in the body and are carried tothe lungs in the venous blood.

2. Some megakaryocytes in the lungs evidently deliver platelets to theblood.

3. Surgery is a potent stimulus to megakaryocyte production; the numbersof megakaryocytes found in the lung postoperatively is significantly increased.

Submitted on July 3, 1964 Accepted on September 19, 1964  相似文献   
73.
ABSTRACT: Previous studies employing ultraviolet light-induced (UV-induced) and methylcholanthrene-induced (MCA-induced) tumors have elucidated the presence of three functionally denned groups of tumor antigens. One is the tumor-specific transplantation antigens (TSTA), which represent the most potent tumor-rejection antigens. The second is the tumor-associated transplantation antigens (TATA), which appears to be etiology-dependent (ultraviolet light-UV-or methylcholanthrene-MCA) and is capable of acting as a rejection antigen following hyperimmunization. The third is the tumor-associated antigens (TAA) which, to date, has only been defined by in vitro assays. The TAA appear to be present on all murine tumors tested. We feel that the TAA are functionally related to fetal antigens. In these experiments, cytotoxic T lymphocytes (CTL) generated from the popliteal lymph nodes of C3H mice immunized with a C3H, UV-induced tumor (RD-1024) were capable of causing specific lysis of not only the immunizing tumor but also of fetal fibroblasts (FFB) and placental cells (PC) obtained from syngeneic C3H × C3H matings. In cold-cell inhibition experiments, unlabeled placental cells could abolish specific lysis of labeled placental cell targets, fetal fibroblast targets, and secondary tumor targets (LR80, a MCA-induced tumor) while not inhibiting lysis of the immunizing tumor. Placental cells and fetal fibroblasts from 12-day to 14-day syngeneic C3H pregnancies were capable of eliciting a CTL response by footpad immunization of virgin C3H female mice. Anti-FFB or anti-PC CTL were capable of killing all tumors tested (UV-induced or MCA-induced) and were without H-2 restriction as demonstrated by specific lysis of a BALB/c tumor. These results indicate that antigenic determinants present on 12-day to 14-day fetal and placental cells satisfy the functional definition of the TAA.  相似文献   
74.
Highly purified basic proteins have been isolated from bovine and turkey brains by a novel method employing acid-acetone extraction. The final product gave a single band on polyacrylamide gel electrophoresis at pH 4.3 and in the presence of sodium dodecyl sulfate. Both proteins have arginine at the COOH-terminus while the NH2-terminal residue cannot be detected and is probably blocked. A higher ratio of histidine to lysine and a greater proportion of serine and valine was found for the turkey compared with the bovine protein. Both proteins contain one tryptophan and two methionine residues. However, it was found from cyanogen bromide treatment that there is a marked difference in the location of one of the methionine residues, while the tryptophan-containing peptides liberated after trypsin digestion have different mobilities on peptide maps. When dissolved in water these proteins give a typical random coil curve from circular dichroism (CD)*, whereas in 80% methyl alcohol they assume a 25% α-helix.  相似文献   
75.
76.
Teratology Study in Rats with Amsacrine, an Antineoplastic Agent.ANDERSON, J. A., PETRERE, J. A., SAKOWSKI, R., FITZGERALD, J.E., AND DE LA IGLESIA, F. A. (1986). Fundam. Appl. Toxicol.7, 214–220. Amsacrine, an acndinylamino derivative usedin the treatment of refractory leukemias, was evaluated forits teratogenic potential in pregnant rats. The compound wasgiven by intrapentoneal (ip) administration on Days 6 to 9 ofgestation to groups of 20 female CD rats at levels of 0.5, 1.0,and 2.0 mg/kg. Appropriate vehicle and untreated controls wereincluded. Dams given 2.0 mg/kg lost weight during and afterthe treatment period. Food consumption was comparable to controlsat all dose levels except for the high dose group in the post-treatmentperiod. Decreased litter size, increased postimplantation loss,and reduced fetal weights occurred with doses of 2.0 mg/kg.Significantly reduced fetal body weight and increased incidenceof stunting were the only adverse findings at 0.5 and 1.0 mg/kg,respectively. Two fetuses at 2.0 mg/kg, one at 1.0 mg/kg, oneat 0.5 mg/kg, and two vehicle control fetuses had gross abnormalities.Fetotoxicity, manifested by inhibition of osteogenesis and minorskeletal abnormalities, occurred with doses of 0.5 mg/kg ormore. The results indicate that amsacrine was embryolethal torats at doses of 2.0 mg/kg and embryotoxic at lower dose levels.Teratogenicity was not evident at doses which did not affectfetal survival.  相似文献   
77.
78.
Chronic Morpholine Exposure of Rats. HARBISON, R. D., MARINO,D. J., CONAWAY, C. C., RUBIN, L. F., AND GANDY, J. (1989). FundamAppl. Toxicol. 12,491–507. The chronic toxicity and carcinogenicpotential of morpholine were evaluated in 60 Sprague-Dawleyrats/sex/group receiving morpholine at mean inhalation exposureconcentrations of 0, 10, 50 and 150 ppm for 6 hr/day, 5 days/week,for 104 weeks. Survival, body weight gains, organ weights, hematology,and clinical chemistries were normal in exposed groups and comparableto those of the control animals. The incidences of palpabletissue masses and of histologically confirmed neoplasia werecomparable among all groups, including the control groups, andwere typical of the strain and age of the rats tested. In-lifeclinical examinations revealed increased incidences of irritationaround the eyes and nares, chromadacryorrhea, and urine stainson the fur, predominately in high-dose animals. Morpholine exposurewas associated with corneal irritation seen by ophthalmoscopicexamination and confirmed microscopically as keratitis limitedto the highest exposure group. Irritation of the maxillary andnasoturbinates as indicated by infiltration of neutrophils,focal squamous metaplasia of the turbinate epithelium, and necrosisof the turbinate bone was observed in high-dose animals. Therefore,chronic exposure of rats to morpholine for 2 years at concentrationsof 150 ppm or less revealed no carcinogenic potential or chronicsystemic toxicity. Consistent with its known irritating properties,morpholine produced only local irritation, which was limitedalmost exclusively to high-dose animals.  相似文献   
79.
N-Methylformamide (NMF) is a metabolite of dimethylformamide(DMF), a solvent with wide applications in the chemical industry.The potential developmental toxicity of NMF was evaluated inCD rats and New Zealand white rabbits. Pregnant rats and rabbitswere dosed once daily by gavage on Gestation Days 6–15and 6–18, respectively. Doses for rats were 0, 1, 5, 10,or 75 mg/kg; doses for rabbits were 0, 5, 10, or 50 mg/kg. Cesareansections were performed on rats and rabbits on Gestation Days20 and 29, respectively. No treatment-related maternal deathsor clinical signs occurred in either species. Body weight gainand food consumption were depressed in rats given 75 mg/kg andrabbits given 50 mg/kg. Fetal viability was reduced at 75 mg/kgin rats and at 50 mg/kg in rabbits. In rats, a significant increasein the incidence of malformations including cephalocele andstern-oschisis was observed in fetuses from the 75 mg/kg group.In addition, a developmental delay was indicated by reductionof fetal weight and by a significant increase in the occurrenceof incomplete ossification of various skeletal structures. Inthe rabbit, fetal body weight was reduced at 50 mg/kg. Malformationsobserved at 50 mg/kg included gastroschisis, cephalocele, domedhead, flexed paw, and skull and sternum anomalies. The lowest-observed-adverse-effectlevels for maternal and developmental toxicity in the rat andrabbit were 75 and 50 mg/kg, respectively. The no-observed-adverse-effectlevel for maternal and developmental toxicity in the rat andrabbit was 10 mg/kg.  相似文献   
80.
Surgical Treatment of Supraventricular Tachycardia: A Five-Year Experience   总被引:2,自引:0,他引:2  
Two hundred and eight patients underwent operative therapy of supraventricular tachycardia between June 1984 and June 1986. There were 196 patients with Wolff-Parkinson-White syndrome, one with AV nodal reentry, two with atrial flutter, one with ectopic atrial tachycardia, three with paroxysmal sinus tachycardia, and five with atrial fibrillation. Map guided or direct surgery was performed in all patients except the three with atrial fibrillation. Direct surgery was generally successful with failures including one patient with Wolff-Parkinson-White syndrome, one with atrial flutter, and the three patients with paroxysmal sinus tachycardia. There was no mortality. Major complications were uncommon and included three resternotomies for bleeding, one chylopericardium. Six patients required reoperation.  相似文献   
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