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891.
Heparin therapy in the Chinese--lower doses are required   总被引:1,自引:0,他引:1  
Warfarin requirements are lower in the Chinese, but it is not known if this applies to heparin. We investigated the optimal dose for heparin therapy in Chinese patients, and to assess relationship between i.v. heparin dosage and anticoagulation efficacy. One hundred Chinese patients requiring intravenous heparin therapy were given an initial bolus followed by continuous intravenous infusion. The main outcome measures were: (i) Efficacy of anticoagulation assessed by blood coagulation studies (APTT) compared to heparin dosage, (ii) Determinants of dosage variation-age, gender, body weight, height, indication for heparin therapy and number of medications, other disease, and serum albumin level. It was found that the mean therapeutic infusion dose requirement of heparin was 848.7 +/- 274.7 units/h, 79% required a dose of 1000 units/h or less. Heparin dose correlated negatively with age (r = -0.40; p < 0.001) and positively with weight (r = 0.44 p < 0.001) and height (r = 0.49; p < 0.001). Chinese subjects require lower heparin doses (about 800 units/h) than usually recommended for Caucasians (usual dose 1000-1500 units/h). This can be partly explained by the lower body weight in Chinese patients.   相似文献   
892.
One hundred and one patients with cirrhosis resulting from alcoholabuse, admitted to Broussais University Hospital, Paris, betweenJanuary, 1986 and December, 1989 were assessed for infectionof the ascitic fluid using clinical and cytobacteriologicalcriteria. All of 46 patients (45.5%) with clinical signs andsymptoms of peritonitis had an ascitic fluid polymorphonuclear(PMN) count > 250 cells/mm3. Bacteria could be isolated fromthe ascitic fluid of 23 patients (50%). Twenty-six bacterialstrains were isolated(there was more than one strain in twosamples). Escherichia coli was found in 14 cases. It is noteworthythat no anaerobes were grown. Mortality, biochemical parametersand clinical features correlated significantly with an asciticfluid PMN count > 250 cells/mm3. High mortality correlatedwith a PMN count > 1000 cells/mm3 (70% vs. 33%).  相似文献   
893.
Growth and development following marrow transplantation for leukemia   总被引:1,自引:3,他引:1  
One hundred forty-two patients between the ages of 1 and 17 years who survived disease-free more than 1 year after marrow transplantation for hematologic malignancy had growth and development evaluations from one to 14 years posttransplant (median 4 years). Prior to transplant all children received multiagent chemotherapy and 55 also received central nervous system irradiation, but none had growth and development evaluations. Marrow transplant preparation included high-dose chemotherapy and total body irradiation (TBI) given as a single dose of 9.2 to 10.0 Gy (79 patients) or as fractionated doses of 2.0 to 2.25 Gy/d for six to seven days (63 patients). After transplant abnormal thyroid function was present in 39%. Stimulated 11-desoxycortisol levels were subnormal in 24% of patients evaluated. Growth hormone (GH) deficiency was present in 17 of 25 children who received previous cranial irradiation. Partial GH deficiency was present in 4 of 25 who received previous cranial irradiation and in 6 of 18 who had not received cranial irradiation. Height velocity was decreased in all patients. After transplant, height was significantly influenced by chronic graft-v-host disease and single-dose TBI. Sixty-eight percent had delayed development of secondary sexual characteristics. Gonadal failure occurred in nearly all who were postpubertal at transplant. While it is not possible to determine how many of these endocrine abnormalities occurred as a result of treatment administered prior to transplantation, these data do demonstrate that children who become long-term survivors after marrow transplantation for hematologic malignancy have endocrine abnormalities that adversely affect growth and development.  相似文献   
894.
895.
A variant of von Willebrand disease (vWD) was identified in six members of a kindred spanning four generations. The proband was a 46-year-old woman with a lifelong history of bleeding, a prolonged bleeding time (> 15 minutes), markedly elevated von Willebrand factor (vWF) antigen (vWF:Ag = 2.09 U/mL), slightly reduced ristocetin cofactor activity, and a plasma vWF multimer pattern similar to that of vWD type IIC. Similar findings were observed in her three children, mother, and brother. In affected family members, platelet and plasma vWF multimer patterns were discrepant with higher molecular weight multimers observed in platelet vWF. Following a 1-Des-amino-8-D-arginine vasopressin (DDAVP) challenge, the proband failed to normalize her bleeding time even though vWF: Ag rose by 70% and higher molecular weight multimers were increased slightly. Genetic studies were consistent with autosomal dominant inheritance of a mutation within the vWF gene. By sequencing of cloned genomic DNA, mutations were excluded in exons 4, 5, 14, and 15, which encode regions of the vWF propeptide proposed to be important in multimer biosynthesis. Mutations also were excluded in exons 28 to 31, which encompass the known mutations that cause vWD types IIA, IIB, and B. This new variant of vWD, characterized by autosomal dominant inheritance, a qualitative defect that resembles vWD type IIC, and increased plasma vWF:Ag, was tentatively designated vWD type IIC Miami.  相似文献   
896.
Stoehr  SJ; Smolen  JE 《Blood》1990,75(2):479-487
Investigations of protein kinase C (PKC) activity have focussed on protein phosphorylation using adenosine triphosphate (ATP), not guanosine triphosphate (GTP), as the phosphate donor. In a continuing study of the enzymology of the PKC of human neutrophils, we wanted to determine if there might be protein kinases that do use GTP as a phosphate donor. Soluble extracts or detergent-extracted fractions of human neutrophils were used as enzyme sources. Phosphorylation of histone using [gamma-32P]-GTP was 31% as effective as [gamma-32P]-ATP. Phosphorylation with GTP depended on Ca2+, Mg2+, and phospholipid, just as the ATP, and the Ca2+ requirements were similar. In all cases, H-7, an inhibitor of ATP-supported PKC activity, blocked GTP-utilizing activity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed that similar endogenous proteins were phosphorylated with ATP or GTP. The apparent Km and Vmax for the enzyme(s) for both phosphate donors were identical, although these were modified by treatment with Triton X-100. GTP competitively inhibited use of ATP by PKC; however, low concentrations of ATP enhanced GTP- utilizing kinase activity in some cases. Non-hydrolyzable forms of ATP and other nucleotide triphosphates were inhibitory. Detergent treatment also markedly altered the number of proteins phosphorylated by either nucleotide. The major protein phosphorylated in the soluble or detergent extract was a single polypeptide band in the 34 Kd range. These studies are the first to explicitly examine the possible phosphorylation by neutrophil PKC using GTP and point to a potential alternative mode of enzyme activity. Since high concentrations of GTP are available within neutrophils, the ability of PKC or a PKC-like enzyme to use this nucleotide may have important ramifications in signal transduction.  相似文献   
897.

Background

The use of non-steroidal anti-inflammatory drugs (NSAIDs) is associated with serious adverse drug events (ADEs).

Aim

To determine the prevalence of over-the-counter (OTC) NSAID use in the general population and in patients with a high risk of developing a serious NSAID-related ADE.

Design and setting

Cross-sectional study in four general practices in the Netherlands.

Method

Two patient samples were selected: a random sample of adults (general population sample); and adult patients with a high risk of developing a serious ADE in case of NSAID use (high-risk sample). All included patients were sent a questionnaire regarding their use of OTC NSAIDs in the 4 weeks prior to participation.

Results

In the general population sample, 118 of 456 (26%) invited patients completed the questionnaire. Of these, 35 (30%) had used an OTC NSAID. In the high-risk sample, 264 of 713 (37%) invited patients completed the questionnaire, and of these high-risk patients 33 (13%) had used an OTC NSAID. Over 20% of OTC NSAID users in the general population sample and over 30% in the high-risk sample had used the OTC NSAID for >7 days. OTC NSAIDs were used in a dosage exceeding the recommended daily maximum by 9% and 3% of OTC NSAID users in the general population and the high-risk sample respectively.

Conclusion

OTC NSAIDs are used by almost one-third of the general population. In the high-risk patients selected, one in eight patients used an OTC NSAID. Continued efforts by health authorities and healthcare professionals to inform patients of the risks of these drugs are warranted.  相似文献   
898.
Helicobacter pylori causes chronic active gastritis and is thought to be associated with the development of gastric atrophy, intestinal metaplasia and carcinoma. As the effect of H. pylori eradication on this process is poorly understood, we sought to determine the long-term effects of H. pylori eradication on gastric histology. Fifty-four patients with duodenal ulceration associated with H. pylori infection received H. pylori eradication therapy in 1985/86 and either remained infected (n= 22) or had the infection eradicated (n= 32); patients were followed up by endoscopy with gastric antral biopsy for 7.1 years (mean). Histopathological analysis of gastric antral mucosa from patients rendered H. pylori-negative revealed a marked decrease in both inflammatory cells within the lamina propria and intraepithelial neutrophils and an increase in epithelial mucinogenesis. Gland atrophy remained unchanged in both H. pylori-positive and -negative patients. When examined for the presence and severity of intestinal metaplasia, there was neither a difference between the two patient groups nor a change with time. These data demonstrate that significant long-term improvements in gastric histology accompany H. pylori eradication when compared with histology in patients with persistent infection. Whether this confers a protective effect by reducing the risk of gastric carcinoma remains unknown.  相似文献   
899.
900.
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