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141.
Thrombomodulin, an endothelial anticoagulant protein, is absent from the human brain 总被引:10,自引:1,他引:10
Protein C activation by thrombin is significantly accelerated by the endothelial cell cofactor, thrombomodulin. In this study, we have developed a radioimmunoassay for thrombomodulin and have measured the cofactor content in several human tissues. The assay method detects as little as 2 ng of thrombomodulin. The highest thrombomodulin content was found in lung and placenta, but the antigen was also detected in spleen, pancreas, liver, kidney, skin, heart, and aorta. Unexpectedly, thrombomodulin was absent from brain. Extracts from cerebral cortex, cerebellum, centrum semiovale, midbrain, basal ganglia, pons, and medulla were devoid of thrombomodulin. In contrast, thrombomodulin antigen is present in extracerebral intracranial vessels, including basilar and internal carotid arteries and choroid plexus, as well as in endothelium of the pia-arachnoid. 相似文献
142.
A prospective trial was undertaken to evaluate the efficacy of stimulated
in-vitro fertilization (SIVF) and stimulated intrauterine insemination
(SIUI) in couples with unexplained and mild male factor infertility. In
all, 80 couples were allocated to treatment with SIVF or SIUI, both
treatments following the same protocol [clomiphene citrate and follicle
stimulating hormone (FSH) injection], except that higher doses of FSH were
used in the SIVF treatment cycles. Initially, 41 couples were allocated to
and started treatment with SIVF but eight cases were eventually converted
to SIUI because of under-response. Similarly, although 39 couples were
initially allocated to SIUI treatment, five of these converted to SIVF
because of over-response. The treatment cycles that were converted either
to SIUI or to SIVF were not considered as treatment failures but as
treatment changes and so were included in the analyses. Of the final 38
SIVF cycles, four were cancelled (dysfunctional response), failed
fertilization occurred in five cycles and 29 subjects reached embryo
transfer. There were two biochemical pregnancies [positive human chorionic
gonadotrophin (HCG) only], two clinical abortions and seven live births. Of
the final 42 SIUI cycles, only two were cancelled, insemination being
performed in the remaining 40 cases. The result was one clinical abortion,
three ectopics and eight live births. The proportion of cycles with
positive HCG was identical (28.9% per cycle treated for SIVF and 28.6% for
SIUI) and the livebirth rates were also not different (18.4% per cycle
treated for SIVF and 19.0% for SIUI). The cost per maternity of SIUI was
approximately half that of SIVF (Pounds Sterling 1923 versus Pounds
Sterling 4611) and so we conclude that, as SIUI had an efficacy that was
not significantly different from SIVF (using similar protocols) but was
more cost-effective, it must be considered the more appropriate form of
management for the treatment of unexplained and mild male factor
infertility. Indeed, it is hard to justify the routine use of IVF, as a
first approach, in unexplained infertility.
相似文献
143.
144.
由于妊娠期母体生理功能的改变,药物更易于通过胎盘进入胎儿体内。妊娠期用药不当可导致胎儿畸形或死亡。本文就耳鼻咽喉科常用的几类药物在妊娠期的应用指征做一编译,以供同道们参考。 相似文献
145.
Solitary pulmonary nodules: CT assessment 总被引:29,自引:0,他引:29
Siegelman SS; Khouri NF; Leo FP; Fishman EK; Braverman RM; Zerhouni EA 《Radiology》1986,160(2):307-312
Computed tomography (CT) was used to examine 634 solitary pulmonary nodules (SPNs). Each lesion was assessed as benign or indeterminate on the basis of CT criteria. Benign nodules made up 44% of all SPNs and 58% of the 431 that were 2 cm or less in diameter. All malignant SPNs were assessed as indeterminate, and adenocarcinoma (42%) was the most common primary malignancy. A total of 176 (63% of benign SPNs) were correctly assessed as benign by CT. Ninety SPNs assessed as diffusely calcified were not so identified by conventional tomography at outside institutions. An SPN can be reliably assessed by CT as benign if it exhibits high attenuation values, exceeding a critical level and distributed diffusely throughout a CT section through the center of the lesion and a well-defined edge. Although 38 of 283 (13.4%) primary lung cancers contained localized calcification, there was no significant overlap with the diffuse calcification of benign lesions. Central carcinoid tumors may contain focal ossification, but such lesions may be recognized by noting the proximity of larger bronchi. Assessment of SPNs by CT is most effective for lesions 2.0 cm or less in diameter. For larger lesions, the frequency of benign disease was decreased (14.3% of 203), as was the percentage of benign SPNs correctly assessed as benign by CT (37.9%). 相似文献
146.
147.
RP Ford EA Mitchell AW Stewart R Scragg BJ Taylor 《Archives of disease in childhood》1997,77(1):54-55
One component of the Back to Sleep campaign to reduce the risk of sudden infant death syndrome (SIDS) is the recommendation that parents seek medical attention if their infant is unwell. The aim of this study was to investigate of SIDS could in part be explained by sick infants not getting appropriate medical care. Data on symptoms of illness and on acute medical contacts made for infants dying from SIDS (n = 390) within two weeks of their death were compared with those from a randomly selected group of control infants (n = 1592). SIDS cases had more severe illness than controls (odds ratio (OR) = 3.43; 95% confidence interval (CI) = 1.69 to 5.38), and were more likely to have seen a general practitioner (OR = 1.37; 95% CI = 1.09 to 1.73) or attended hospital (OR = 3.43, 95% CI = 1.09 to 1.73). Only 1.3% of all SIDS cases had symptoms suggesting severe illness and had not seen a general practitioner. A lack of medical contacts in the two weeks before death does not contribute to the risk of SIDS. 相似文献
148.
Hanway D Chin JK Xia G Oshiro G Winzeler EA Romesberg FE 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(16):10605-10610
A competitive growth assay has been used to identify yeast genes involved in the repair of UV- or MMS-induced DNA damage. A collection of 2,827 yeast strains was analyzed in which each strain has a single ORF replaced with a cassette containing two unique sequence tags, allowing for its detection by hybridization to a high-density oligonucleotide array. The hybridization data identify a high percentage of the deletion strains present in the collection that were previously characterized as being sensitive to the DNA-damaging agents. The assay, and subsequent analysis, has been used to identify six genes not formerly known to be involved in the damage response, whose deletion renders the yeast sensitive to UV or MMS treatment. The recently identified genes include three uncharacterized ORFs, as well as genes that encode protein products implicated in ubiquitination, gene silencing, and transport across the mitochondrial membrane. Epistatsis analysis of four of the genes was performed to determine the DNA damage repair pathways in which the protein products function. 相似文献
149.
In vivo platelet activation in beta-thalassemia major reflected by increased platelet-thromboxane urinary metabolites 总被引:2,自引:2,他引:2
Increased frequency of thromboembolic events has been recently observed in patients with beta-thalassemia major (TM). Platelet function anomalies including impaired aggregation, increased circulating aggregates, and our finding of shortened platelet survival indicate that platelets may be involved in the hypercoagulability in thalassemia. Consequently, we used a technique based on thin layer chromatography purification and enzyme immunoassay to measure urinary metabolites of thromboxane A2 (TXA2) and prostacyclin (PGI2) in nine splenectomized patients with beta-TM regularly transfused, five non- splenectomized patients with beta-thalassemia intermedia (TI), and 20 healthy individuals. A significant 4- to 10-fold increase was observed in the urinary excretion of 2,3-dinor-TXB2, 11-dehydro-TXB2 and 2,3- dinor-6-keto-PGF1 alpha in patients with TM and TI as compared with healthy controls. No significant differences were found in the concentrations of these metabolites between TM and TI patients. Six TM patients received a very low dose of aspirin (20 mg/day) for 7 days. A significant decrease was observed in the urinary concentrations of 2,3- dinor-TXB2 and 11-dehydro-TXB2 derived from platelets. However, the levels of urinary 2,3-dinor-6-keto-PGF1 alpha reflecting vascular production and TXB2 and 6-keto-PGF1 alpha originating from the kidney were not significantly changed. These results are consistent with those of increased in vivo production of TXA2 because of endogenous platelet activation. 相似文献
150.
GTA Jombo EM Mbaawuaga Akaa P Denen AM Dauda KI Eyong JT Akosu EA Etukumana 《Asian Pacific journal of tropical medicine》2010,3(7):563-566
ObjectiveTo ascertain the role of traditional healers in malaria treatment and its impact on control of the disease.MethodsThe study was cross-sectional in nature. Test-run structured and semi-structured questionnaires were either interviewer or self administered to adult women aged 18 years old and above. House holds were selected using systematic random sampling methods. Information such as age, educational level, marital status, occupation and methods of malaria treatment were obtained. Focused group discussions about beliefs and perceptions on utilization of traditional healers and in depth discussions on treatment and control of malaria were also carried out.ResultsOf the 2 075 respondents studied, 49.7% (n=1 031) utilized traditional healers for treatment of malaria, including 16.7% (n=172) utilizing traditional healers strictly while 83.3% (n=859) combining it with other treatment methods such as hospital/clinic, pharmacy/chemist shop, herbs or spiritual healing. The major contributors to utilization of traditional healers were: illiteracy and ignorance, poverty, unemployment/underemployment and slow pace of the comprehensive package implementation of the “roll back malaria” (RBM) programme initiate in the community.ConclusionsHealth education should be intensified while adequate facilities put in place to commence home management of malaria and probable free distribution of the artemisinin-based combination therapy (ACT). 相似文献