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21.
McGuire  M; Smith  BL; Agre  P 《Blood》1988,72(1):287-293
Hereditary elliptocytosis is a heterogeneous disorder resulting from defects in the erythrocyte membrane skeleton. Although some cases of elliptocytosis result from defects in spectrin, the specific structural abnormality has yet to be identified in the majority of cases. Protein 4.1 plays an essential role in erythrocyte membrane physiology, and deficiencies have been implicated in only a few rare cases of elliptocytosis. By using 4.1 immunoblots and a 4.1 radioimmunoassay we identified distinct variants of protein 4.1 in 15 elliptocytic members of three US white families with the Rh-linked form of elliptocytosis. Elliptocytic members of family G were heterozygotes for a low-molecular weight (mol wt) 4.1 variant (65,000 to 68,000 daltons; normal, 80,000) inherited in linkage with the Rz phenotype. Elliptocytic members of family C expressed a simple partial deficiency of protein 4.1 (63% of the normal level) that was inherited in linkage with the r phenotype. Elliptocytic members of family N were heterozygotes for a high-mol wt 4.1 variant (100,000 daltons) also inherited in linkage with the r phenotype. These studies indicate that mutant forms of protein 4.1 are not uncommon in elliptocytosis among whites and that different kindreds probably express different mutations. The observed linkage of elliptocytosis and Rh blood type most likely results from the close proximities of the 4.1 gene (site of the mutation) and the Rh gene, which is located nearby on the short arm of chromosome 1.  相似文献   
22.
Ornithine carbamoyl transferase (OCT) activity and other liver function tests were studied in a total of 50 patients of clinical malaria and 15 controls. They were grouped as group I (positive for malarial parasite on peripheral blood smear, n=18), group II (negative for malarial parasite on peripheral blood smear (PBS) but responded to antimalarials, n=17) and group III (peripheral blood smear negative and did not respond to antimalarial therapy, n=15). The mean OCT levels were significantly raised in group I (6.79 ± 1.84 IU/L, p value = 0.006) and group II (5.0 ± 1.15 IU/L, p value = 0.014) as compared to controls (2.5 ± 1.13 IU/L) and returned to normal after treatment In contrast, group III had normal levels except in a case of kala azar and septicemia where OCT levels were high and increased further on treatment. Taking PBS positivity as a gold standard of diagnostic criteria, OCT had a sensitivity of 83% and specificity of 86% with a high positive predictive value of 88% as compared to ALT which had a lower sensitivity of 55% and specificity of 80%. The clinical response rate in PBS negative cases of fever having high OCT level was 83% as compared to 35% in cases with normal OCT level, making OCT a good surrogate marker of malaria. OCT levels could also be of prognostic significance as 2 cases of cerebral malaria had high OCT levels of 11.1 UAL and 10.7 IU/L, respectively.Key Words: Malaria, Ornithine carbamoyl transferase  相似文献   
23.
The present study was undertaken to assess the temporal association between the profiles of serum concentrations of oestradiol-17beta, progesterone, chorionic gonadotrophin (CG) and relaxin in pregnancies established naturally, and after embryo transfer, as well as in failed pregnancies in rhesus monkeys. In naturally mated cycles (group 1) a conception rate of 75% was obtained. In group 1, the mean day of CG detection in serum was 11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day post-ovulation. In group 2, embryo transfer to synchronous, non-mated surrogate recipients was performed; seven embryo transfer cycles yielded three pregnancies which were allowed to continue to term and normal infants were delivered. In embryo transfer cycles the mean day of CG detection was 14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day post-ovulation. A delay of about 3 days was observed in the appearance in circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between natural mated and embryo transfer conception cycles. Significant differences (P < 0.05 for progesterone and P < 0.03 for oestradiol) were obtained for the areas under the curves for progesterone and oestradiol between days 12 and 16 in conception cycles compared with failed pregnancies. These data provide the first observation of the normal hormonal signals associated with maternal recognition of transferred embryos during the peri- implantation period, and suggest that the use of such an experimental primate embryo transfer model may help to elucidate components of maternal and embryonic signal-response mechanisms during embryo implantation.   相似文献   
24.
急性有机磷农药中毒120例的救治   总被引:1,自引:0,他引:1  
0 引言 近年来 ,我科在救治急性有机磷农药 (organophos-phorus,OP)中毒方面 ,积累了一些经验 ,现报告如下 .1 对象和方法1 .1 对象 本组 1 2 0例符合《急诊急救学》中的诊断标准 [1 ](男 2 9例 ,女 91例 ) ,年龄 1 .5~ 70岁 ,平均 2 8.6岁 .经口中毒 99例 ,经皮肤中毒 2 1例 .轻度中毒 1 5例 ,中度中毒 42例 ,重度 (含极重度 )中毒 6 3例 . 1 996年 39例 ,1 997年 43例 ,1 998年 38例 . DDV 79例 ,乐果 2 0例 ,混合性中毒 1 0例 ,水胺磷 3例 ,氧化乐果、 391 1、 1 0 5 9、对硫磷各 2例 ,敌百虫 1例 ,药名不详 1 0例 .服毒量 >2 5 …  相似文献   
25.
AJ Unwin  BL Smith  RL Allum  G Singer  JMR Burwell   《The Knee》1995,2(4):233-234
We performed a randomized doubled-blind study to evaluate whether there was a benefit in delay in tourniquet deflation with intra-articular administration of morphine and bupivacaine following operative arthroscopic surgery. In 34 patients the tourniquet was deflated immediately and in 38 patients the tourniquet remained inflated for 10 min following injection. The analgesic efficacy was assessed using pain scores and the amount of supplementary analgesia required. The results demonstrate no benefit in delay in tourniquet deflation.  相似文献   
26.
Taylor  GA; Fitz  CR; Miller  MK; Garin  DB; Catena  LM; Short  BL 《Radiology》1987,165(3):675-678
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis.  相似文献   
27.
Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US.  相似文献   
28.
We characterized the virtual absence of immunoassayable thyroglobulin (Tg) in the serum and thyroid gland of two siblings (MA, JNA) and one nephew (RSS) from a family without inbreeding or familial goiter. Diagnosis of defective Tg gene expression was based on findings of normal PBI and low serum T4, low or normal serum T3, negative perchlorate discharge test, and virtual absence of the serum Tg response to challenge by bovine TSH. This conclusion was confirmed by analysis of proteins in the goiter extracts. Only minute amounts of immunoassayable Tg were detected by RIA (MA, 0.11; JNA, 0.19 mg/g tissue; compared to 70-90 mg/g in normal thyroid tissue). Gel filtration in Sephacryl S300 showed the absence of a normal Tg peak at 280 nm and concentration of label mostly on albumin. A minor intermediate peak of radioactivity was also detected, with the size of, approximately, normal Tg. Sodium dodecyl sulfate-agarose gel electrophoresis indicated the absence of Tg dimer and monomer, and Western blotting and immunoelectrophoresis confirmed this finding. Dot blot quantification of Tg and thyroid peroxidase mRNA indicated decreased hybridization of the patients' mRNA (MA, 44%; JNA, 63%) with phTgM2 (Tg probe) and increased hybridization (MA, 191%; JNA, 182%) with the pM5 (thyroid peroxidase probe) compared with control thyroid tissue. Dot blot analysis of Tg mRNA from the two siblings weakly hybridized with 3' and 5' Tg probes. RNA analysis by means of Northern transfer showed a clear signal of hybridization with Tg probe (phTgM1) in the 8- to 9-kilobase range, corresponding to the normal size Tg mRNA. No major polymorphisms were noted in Southern blotting, using seven restriction endonucleases. We conclude that no gross alteration of the 5' region of Tg gene was present in these patients. Ultrastructural examination of the thyroid tissue indicated that the rough endoplasmic reticulum was not augmented, nor were the cisternae of rough endoplasmic reticulum dilated. The defect observed in these goiters is diminished tissue concentration of Tg mRNA with defective translation. However, small amounts of functionally active Tg could be synthesized, iodinated, and immediately hydrolized, yielding mostly T3, owing to the intense tissue stimulation by TSH.  相似文献   
29.
Cyproterone acetate given as a single intramuscular dose of 300 mg monthly for 6 months resulted in significant reduction of hirsutism without appreciable side effects. This regimen resulted in decreased levels of luteinizing hormone (LH) and estradiol in the eight women studied. No significant changes were observed in total serum testosterone (T) levels, however, there was a reduction in sex hormone binding globulin (SHBG), resulting in lowered SHBG-bound T, and an increase in non-SHBG-T over this time. Serum androstanediol glucuronide levels decreased in three of four women, although not to normal levels.  相似文献   
30.
We studied a 23-yr-old woman with scleroderma and type B insulin resistance. The association with autoimmune disease suggested that the insulin resistance resulted from autoantibodies to the insulin receptor. However, in preliminary studies, serum antireceptor antibodies were not detected in an assay that measures the ability of the antibodies to inhibit insulin binding to the insulin receptor. Antireceptor antibodies were subsequently detected by their ability to immunoprecipitate affinity-labeled receptors. After the patient had received immunosuppressive therapy with prednisone and cyclophosphamide for 3 months, her insulin resistance remitted, and she developed hypoglycemia. Simultaneously with the remission of insulin resistance, the titer of serum antireceptor antibody (measured by the immunoprecipitation assay) fell to less than 1% of the previous level. In a series of 21 patients, this is the first patient with antireceptor antibodies that bound to the insulin receptor without inhibiting insulin binding.  相似文献   
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