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41.
Strain S, a spotted fever group (SFG) rickettsia isolated from Rhipicephalus sanguineus ticks collected in Armenia, was identified. Microimmunofluorescence, sodium dodecyl sulfate-polyacrylamide gel protein electrophoresis and Western immunoblotting, PCR and then restriction fragment length polymorphism analysis, pulsed-field gel electrophoresis, and 16S rRNA gene sequencing were used to compare strain S with reference isolates. Strain S was found to possess proteinic, antigenic, and genomic patterns which were unique among SFG rickettsiae. Strain S is characterized by its high degree of pathogenicity for experimental animals, but its role as a potential human pathogen should be determined. The role of R. sanguineus ticks in the epidemiology of SFG rickettsiae is discussed.  相似文献   
42.
Low affinity FcR are a heterogeneous group of glycoproteinswhich exist in transmembrane (TM) as well as in soluble forms.Two membrane isoforms of the murine type II FcR, FcRilb1 andFc;Rilb2, have been described. They result from the translationof alternatively spliced premRNA, FcRilb2 lacking sequencesof the first intracytoplasmic domain (IC1). Soluble forms ofFcR (sFcR) have previously been shown to result from proteolysisof membrane receptors. We report here the identification, inmacrophages, of a mRNA derived from the FCRll gene by splicingexons encoding the TM and IC1 domains, i.e. corresponding toa TM-deleted FcRllb2 mRNA. A soluble protein possibly encodedby this mRNA was identified in macrophage supernatants. In accordancewith FcR nomenclature, we propose to name this new FcRll IsoformFcRllb3. It is the most abundant 8FcR present in serum, as comparedwith 8FcR resulting from cleavage of membrane FcR.  相似文献   
43.
44.
The concomitant effects of trans-chromosomal allotype suppression of both an a VH and an n Cmu locus allotype in multiheterozygous rabbits were investigated. For example of the expression of the a2 VH and n81 Cmu allotypes were suppressed in a multiheterozygous rabbit having the a1 chi-y-n81de12,15f73g74/a2 chi 32y33n80de12.14f69g77 genotype. This trans-chromosomal allotype suppression led to the concomitant suppression of other CH allotypes in the same parental haplotype as the suppressed-n81 allotype (i.e. the e15, f73 and g74 allotype) and the partial suppression of the a1 VH allotype (from the normal level of 70% of the total Ig to 10%), and also led to compensation by other VH allotypes from the same parental haplotype as the suppressed-a2 allotype (i.e. the x32 and y33 allotypes). The x32 and y33 allotypes were expressed on Ig molecules with the CH allotypes coded by the same haplotype (i.e. the cis molecules). In a further analysis of the IgG molecules having the partially-suppressed-a1 allotype, one-half (5%) of these molecules were trans-chromosomal recombinant molecules (i.e. a1e14 IgG) and the other half (5%) were cis-chromosomal molecules (i.e. a1e15 IgG). The trans-chromosomal a1e14 IgG molecules probably were derived from the expansion of a limited number of lymphoid clones that normally produce only 1.5% trans-chromosomal recombinant molecules. The cis-chromosomal a1e15 IgG molecules were probably derived either from lymphoid clones that survived the suppression by the anti-n81 Ab, or from lymphoid clones that bore a different subclass of IgM (i.e. n-negative IgM).  相似文献   
45.
Nutritional status was evaluated on 210 occasions in 90 pediatric oncology inpatients during a 7-month period; 39 had solid tumors and 51 leukemia. Ages ranged from 3 months to 20 yr. Nutritional parameters were defined as normal, "at risk," or "probably malnourished." Fifty-seven and 29% of assessments revealed at least one parameter "at risk" or "probably malnourished," respectively. Prognosis was negatively related to the number of abnormal nutritional parameters. Serum albumin was most frequently abnormal. However, on most occasions, hypoalbuminemia was associated with weight/height, arm muscle area, and triceps skinfold measurements in the normal range. In order to further identify determinants of serum albumin, we analyzed dietary, chemotherapy, and temperature data in 10 prospectively studied leukemia patients, half of whom received parenteral nutrition. In these patients there was little relationship of serum albumin to chemotherapy or dietary intake. In all of these patients, especially those receiving total parenteral nutrition, low serum albumin was highly associated with fever (p less than 0.0005). We concluded that febrile illness is an important determinant of abnormal serum albumin concentrations. In pediatric cancer patients, abnormal serum albumin may more often reflect the acute metabolic response to fever and infection than depletion of body mass.  相似文献   
46.
Summary Two cases of quadriceps amyotrophy, probably of chronic neurogenic origin are reported. Only the knee jerks were diminished, the calves hypertrophic, and the serum creatine kinase level very high in one case, and there were neurogenic electromyographic abnormalities in the quadriceps. In the first case, biopsy of the quadriceps muscle revealed a neurogenic origin with hyalinized hypertrophic fibres. CT scan showed abnormalities not only in the quadriceps but also in the sartorius, gracilis and gastrocnemius muscles. A second biopsy specimen from the gastrocnemius muscle showed histological findings similar to those of the quadriceps. In the second case, the EMG and biopsy findings suggested a myogenic origin, but 6 years later they were compatible with neurogenic atrophy. Differentiation from Becker dystrophy is very difficult in the first case and the second case is more a focal spinal amyotrophy. Further, in spite of their localization, the extension of the affected muscles changes the diagnosis. The same applies to chronic quadriceps amyotrophy in general, which cannot be regarded as an entity, but which suggests muscular dystrophy, spinal atrophy, polymyositis or a metabolic disorder. These cases can be compared with the four cases reported in the literature, which were regarded as a forme fruste of chronic spinal amyotrophy.  相似文献   
47.
Auditory evoked responses (AERs) were recorded from 16 autistic children (ages 2–10 years) and age-matched normal and retarded controls. In order to test the ability to form auditory-visual cross-modal associations, often impaired in autism, the effects on AERs of coupling sound and light were studied with a paradigm that did not require the cooperation of the subject. Several differences between groups were found concerning the frequency and the amplitudes of present AERs. The pattern characterizing the effects on AERs of coupling sound and light (conditioning phenomenon) was observed for both autistic and normal controls, and not for retarded children. Results suggest that autistic children may have a real but slow learning ability.This study was supported by C.N.R.S. (UA 596), Biology and Neuropsychiatry, Sécurité Sociale, 1982. We wish to thank M. Barre, A. Lardeux, and L. Crespin for their technical work.  相似文献   
48.
Bariatric surgery is an effective intervention for management of obesity through treating dysregulated appetite and achieving long-term weight loss maintenance. Moreover, significant changes in glucose homeostasis are observed after bariatric surgery including, in some cases, type 2 diabetes remission from the early postoperative period and postprandial hypoglycaemia. Levels of a number of gut hormones are dramatically increased from the early period after Roux-en-Y gastric bypass and sleeve gastrectomy—the two most commonly performed bariatric procedures—and they have been suggested as important mediators of the observed changes in eating behaviour and glucose homeostasis postoperatively. In this review, we summarise the current evidence from human studies on the alterations of gut hormones after bariatric surgery and their impact on clinical outcomes postoperatively. Studies which assess the role of gut hormones after bariatric surgery on food intake, hunger, satiety and glucose homeostasis through octreotide use (a non-specific inhibitor of gut hormone secretion) as well as with exendin 9–39 (a specific glucagon-like peptide-1 receptor antagonist) are reviewed. The potential use of gut hormones as biomarkers of successful outcomes of bariatric surgery is also evaluated.  相似文献   
49.
SETTING:Rural Eastern Cape, South Africa.OBJECTIVE:To identify steps in the TB preventive care cascade from routinely collected data among TB patients at a district hospital prior to the implementation of a novel TB program.DESIGN:This was a retrospective study. We adapted the TB prevention cascade to measure indicators routinely collected at district hospitals for TB using a cascade framework to evaluate outcomes in the cohort of close contacts.RESULTS:A total of 1,722 charts of TB patients were reviewed. The majority of patients (87%) were newly diagnosed with no previous episodes of TB. A total of 1,548 (90%) patients identified at least one close contact. A total of 7,548 contacts were identified with a median of 4.9 (range 1–16) contacts per patient. Among all contacts identified, 2,913 (39%) were screened for TB. Only 15 (0.5%) started TB preventive therapy and 122 (4.4%) started TB treatment. Nearly 25% of all medical history and clinical information was left unanswered among the 1,722 TB charts reviewed.CONCLUSION:Few close contacts were screened or started on TB preventive therapy in this cohort. Primary care providers for TB care in district health facilities should be informed of best practices for screening and treating TB infection and disease.  相似文献   
50.
Mycobacterium leprae was detected by optical microscopy, fluorescent in situ hybridization, and molecular detection in feces collected for the diagnosis of Entamoeba coli enteritis in a leprosy patient in Burkina Faso. This observation raises questions about the role of fecal excretion of M. leprae in the natural history and diagnosis of leprosy.  相似文献   
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