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101.
The heel fat pad is organized, both in structure and in composition, to bear the stresses and strains of normal activities and to permit pain-free weightbearing. The fatty acid composition of heel pads in 11 patients with rheumatoid arthritis, a disease process frequently associated with heel fat pad atrophy, was analyzed using gas-liquid chromatography and was compared with that of patients without systemic disease. The heels of patients with rheumatoid arthritis demonstrated a significant change in the composition of saturated fatty acids when compared with heels of nonrheumatoid patients. This composition reflects an increased fat viscosity, which decreases the ability of the heel to absorb and dissipate the energy generated during ambulation. This factor could cause degeneration of the heel septal system, with resulting fat pad atrophy.  相似文献   
102.
Summary A new approach to avoid typical complications from bone marrow transplantation into MHC different mice was studied. Rat monoclonal anti-Thy-1 antibodies of the IgG2b isotype were identified, which inhibit T lymphocytes in vivo so that transplanted donor T cells as well as residual T cells of the conditioned marrow recipient were suppressed.A single injection of these antibodies after irradiation and before marrow transplantation did not only prevent graft-versus-host mortality but suppressed also host-versus-graft reactivity so that the radiation dose necessary for engraftment of donor cells differing in H-2, IA (both haplotypes) major histocompatibility antigens could be reduced to 6.0 Gy. In addition an anti-T leukemic cell effect from the injected monoclonal T cell antibodies was observed.Supported by SFB 1187  相似文献   
103.
W Kummer 《Annals of anatomy》1992,174(5):409-417
The autonomic nervous system is divided into the sympathetic, parasympathetic and enteric subdivisions. The present review is focussed upon the highly specialized reflex organization and neurochemistry of sympathetic parasympathetic neurons. The currently available informations allow to conclude that autonomic control of each peripheral target tissue is specifically regulated under normal conditions but nevertheless able to respond to altered conditions by changes in neural activity and mediator expression.  相似文献   
104.
Background: Electrical stimulation (ES) of the stomach has been shown to modulate LESP. Electrical stimulation, using neural high frequency stimulation (NGES) can induce contractions of the smooth muscle of the gut. The purpose of this study was to determine if electrical stimulation of the LES can affect LESP. Methods: Four female hound dogs, weight: 20–25 kg, underwent an esophagostomy that allowed the introduction of a sleeve manometry catheter into the esophagus. They were also implanted with a pair of electrodes along the longitudinal axis of the LES. After 3 weeks of recovery, they underwent esophageal manometry recording during control and ES, performed randomly on separate days, using 4 different stimulations: 1‐Low frequency: freq: 6 cycles/min, pulse: 350 milisec, amp: 5 mAmp; 2 High‐frequency: freq: 50 Hz, pulse: 1 milisec, amp: 5 mAmp; 3‐ NGES: freq: 50 Hz, pulse:20 milisec, amp:10 volts; 4‐ High‐frequency, circular: freq: 20 Hz, pulse:1 milisec, amp:5 mAmp. All recordings were performed 1 hour after consumption of 3 ounces of canned dog food, to prevent fluctuations in LESP and under mild sedation (acepromazine 0.5 mg kg­1). Tests consisted, during ES days, of 3 periods of 20 minutes each: control , stimulation and post stimulation. The effect of NGES was also tested under anesthesia and following administration of L‐NAME 50 mg kg­1 IV. and also atropine 0.05 mg kg­1 IV. Analysis: area under the curve (AUC) and pressure were compared among the 3 periods. Data shown as mean ± SD, ANOVA and t‐test, p < 0.05. Results: Sustained increase in LESP was observed during low frequency stimulation, 32.1 ± 12.8 vs. 42.4 ± 18.0 vs. 50.1 ± 23.6, control vs. stimulation vs. post stimulation respectively, p = 0.013. AUC also significantly increased during and after stimulation, 39,320.3 ± 15,722 vs. 51,294 ± 21,826 vs. 59,823.6 ± 28,198.4 mmHgxsec, control vs. stimulation vs. post stimulation respectively, p = 0.01. There was no significant change with other types of ES. NGES induced an initial rise in LESP followed within few seconds by relaxation with slow resumption of pressure over a 1 minute period. L‐NAME increased LESP and augmented the initial rise in LESP following NGES but markedly diminished or abolished the relaxation phase. Atropine lowered LESP and abolished the initial rise in LESP induced by NGES. Conclusions: Low frequency ES of the LES increases LESP in conscious dogs. NGES has dual effect on LESP: an initial stimulation, cholinergically mediated, followed by relaxation mediated by nitric oxide.  相似文献   
105.
Serum carbohydrate antigen 19-9 (CA 19-9) has been identified as biochemical marker for biliary tract cancer (BTC). The purpose of this study was to evaluate its value as a treatment response marker and its value as a prognostic parameter in patients with unresectable BTC. We analyzed 70 patients with BTC treated with chemotherapy. CA 19-9 levels before and after two treatment courses were analyzed with respect to their effect on treatment response. Patients were categorized into two subgroups according to biliary stenting: patients without endoscopic intervention or biliary drainage (non-stent subgroup) and patients with endoluminal stenting (stent subgroup). Pretreatment CA 19-9 levels were prognostic with respect to overall survival for the entire study population. Patients with CA 19-9 levels above the median of 300 units/mL had a nearly 3-fold risk for early death (hazard ratio, 2.92; 95% confidence interval, 1.51-5.64; adjusted P = 0.002) as compared with patients with CA 19-9 levels 相似文献   
106.
107.
ObjectiveTo determine the knowledge of HIV/AIDS among primary school pupils in north central area of Nigeria.Methods2000 randomly selected primary school pupils in and around eastern part of Idoma area of Benue state were interviewed using an open-ended questionnaire. Data analysis was done with EPI-INFO 2000. The Chi-square test was used for statistical analysis and the 0.05 level of significance was adopted.ResultsA totle of 1010 males and 990 females at ages between five and sixteen years were drawn from 10 primary schools in the area. Pupils in the higher classes were more knowledgeable and sex difference was not statistically significant. Certain misconceptions were noted.ConclusionsThere is need for health education for all cadres of primary school pupils in the area, which will increase the awareness of the disease.  相似文献   
108.
Inhibition and potentiation of platelet function by lysolecithin   总被引:1,自引:0,他引:1  
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109.
Paroxysmal nocturnal haemoglobinuria (PNH) is an acquired clonal disorder of haematopoietic stem cells associated with a somatic mutation in the phosphatidylinositol glycan complementation class A (PIG-A) gene. The only curative option is an allogeneic stem cell transplant (SCT), although treatment is hazardous. A 46-year-old male patient with PNH and obvious signs of severe, progressive haemolysis was transplanted in July 2002 with highly purified CD34 T-cell depleted peripheral blood stem cells from his HLA-identical brother. Prior to transplantation, the PNH was resistant to immunosuppressive therapy. The patient received 6.1 x 10(6)/kg bodyweight CD34-positive cells with a proportion of CD3-positive cells of 0.81 x 10(4)/kg bodyweight. After engraftment, 12 days post transplant (neutrophils>1.0/nl) the patient's physical condition steadily improved and parameters of haemolysis decreased. No glycophosphatidylinositol-deficient cells in peripheral blood could be detected by flow cytometry 40 and 100 days after transplant. We conclude that PNH may be cured by allogeneic CD34-enriched SCT from a sibling donor attempting to avoid acute GVHD and to reduce cumulative organ toxicity by using this transplantation modality.  相似文献   
110.
Tuberoinfundibular peptide (TIP39) was initially identified as a neurotransmitter and agonist of the PTH2 receptor, which is expressed in the cardiovascular system. This study documents for the first time the cardiac expression and function of TIP39. Expression was analyzed via RT-PCR. Function was characterized on Langendorff-perfused rat hearts as left ventricular developed pressure (LVDP) and on isolated cells via a cell edge detection system. cGMP levels were detected with RIA. Tuberoinfundibular peptide (TIP39) mRNA was found to be constitutively expressed in coronary endothelium cells, isolated cardiomyocytes, ventricles, atria, and aorta. At first we investigated the vasodilatory properties of TIP39 (100 nM) in the presence of L-nitro-arginine (L-NA, 100 microM). Surprisingly, TIP39 had no vasodilatory effect but decreased LVDP by 35 +/- 7%. In the absence of L-NA, addition of TIP39 decreased LVDP by 8 +/- 2%. The PTH2 receptor antagonist Trp23-Tyr36-PTHrP (1-36, 100 nM) abolished this TIP39 effect in the presence of L-NA. The experiments with isolated cardiomyocytes provided similar results. TIP39 (10 nM) lowered the contraction amplitude by 6 +/- 3%. In the presence of L-NA (100 micromol/liter), TIP39 lowered the amplitude by 34 +/- 6%. cGMP concentration in cardiomyocytes was stimulated by TIP39 (10 nM) in the same range as by the nitric oxide (NO) donor SNAP (100 microM). In the presence of L-NA, this increase was abolished. These results suggest that an inhibition of endogenous NO production unmasks a profound negative inotropic effect of TIP39 that is mediated by an activation of the PTH2 receptor. The results obtained with isolated cardiomyocytes suggest that myocyte-derived NO, rather than vascular NO, is responsible for this effect. cGMP seems to be the downstream signal of produced NO.  相似文献   
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