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31.
The aim of the present research was to study individual response specificity in 22 male patients having essential hypertension (HT) and to compare these patients with age-matched male normotensive controls (NT). Four stimuli, letter identification, mental arithmetic, cold pressor and isometric exercise, were administered while recordings were made of: systolic and diastolic blood pressures, heart rate, respiration, forearm and hand blood flows, and skin conductance level and fluctuations. After each session urine samples were collected and epinephrine and norepinephrine levels were analyzed. Twelve subjects in the HT group were given beta-adrenergic blocking agents and retested 1 to 21 months (X?= 12 months) after the first session. Each response was standardized, using NT as the reference group. Intraclass correlations were computed to evaluate whether HT males reacted with a more consistent hierarchy of responses than did NT. Intraclass correlations were significantly higher among the patients than in the control group, regardless of whether the blood pressure response was included or excluded in the computation of the intraclass correlations. Thus, we conclude that male HT patients show more individual response specificity than NT controls. Beta-adrenergic receptor antagonists reduced levels of cardiovascular activity and attenuated reactivity but did not affect amount of specificity. Thus, intraclass correlations provide unique and useful information, since they are not related to blood pressure reactivity or to urinary catecholamine levels, nor affected by beta-adrenergic blockade.  相似文献   
32.
Skin deposits in hereditary cystatin C amyloidosis   总被引:3,自引:0,他引:3  
Summary Clinically normal skin from 47 individuals aged 9–70 years was investigated. Cystatin C amyloid deposits were found in various locations of the skin by light and/or electron microscopy, in all 12 patients with a clinical history of hereditary cystatin C amyloidosis (HCCA). Six asymptomatic individuals, who had the Alu 1 restriction fragment length polymorphism (RFLP) marker reported to cosegregate with the disease, also had cystatin C amyloid deposits in the skin. Three asymptomatic individuals (age 17–46) belonging to the HCCA families were without amyloid in the skin but had Alu 1 RFLP marker. Skin from 12 individuals who served as controls and skin from 14 close relatives of the patients was negative for amyloid. Punch biopsy of the skin is a simple procedure which is of value for the diagnosis of HCCA, even before the appearance of clinical symptoms. This method might also be of use in following progression of the disease.  相似文献   
33.
The effect of close intraarterial infusions of vasoactive intestinal polypeptide (VIP) on gastric motility, intestinal fluid transport and colonic motility were studied in the cat. Regional blood flow was also followed in all experiments. In the stomach VIP produced a gastric relaxation and a blood flow increase. The motility response was similar to that observed when eliciting the vago-vagal reflex relaxation by distending the esophagus. In the small intestine a hyperemia and a decrease of net water uptake was observed. When infusing small amounts of VIP a decrease of net water uptake was seen without any change of intestinal blood flow. Large amounts of VIP produced a transient secretory state in the small intestine. In the colon a hyperemia was seen immediately upon starting the infusion of the drug. After 2-3 min of infusion a contraction of the colon was apparent. The administration of atropine to the animal did not significantly affect any of the responses produced by VIP. The results are discussed in relation to VIP as a possible neurotransmitter in the gastrointestinal tract.  相似文献   
34.
A solid phase immunoradiometric assay was developed for the quantitation of tryptase released from activated human mast cells. Tryptase exhibits a linear dose-response curve over the standard range of 2-50 micrograms/l in buffer, serum, and plasma. The dose-response curve approached a plateau at a tryptase concentration of 100 micrograms/l and exhibited partial inhibition at concentrations above 10,000 micrograms/l. The sensitivity of the assay was 0.2-0.4 micrograms/l, and the intra-assay and interassay coefficients of variation were below 4% at 2 micrograms/l or higher tryptase concentrations. The recovery of known amounts of purified tryptase added to serum ranged from 91 to 115%. Detection of tryptase was evaluated with several body fluids and was accurate in sera, plasma, bronchoalveolar lavage fluid, nasal lavage fluid, and saliva. The concentration of tryptase was examined in serum samples from 100 healthy controls; in each case the level was less than 2 micrograms/l. The immunoassay also was utilized to examine serum levels of tryptase after the onset of a hypotensive reaction in one patient receiving general anesthesia. A maximally elevated level of tryptase (25 micrograms/l) was detected at the first time point, 0.5 h, and elevated levels persisted to 6 h before a return to normal levels was documented at 24 h. Thus, the involvement of mast cell activation in hypotensive subjects can be ascertained by this new tryptase radioimmunoassay.  相似文献   
35.
The 2001 Bethesda system (TBS 2001) eliminated the "satisfactory but limited by" category, benign cellular changes (BCC), and the designations "favor benign" (ASC-B) and "favor low grade" (ASC-L) for atypical squamous cells. We compared the unsatisfactory rate and atypical squamous cells:squamous intraepithelial lesions (ASC:SIL) ratio pre- and postimplementation of TBS 2001 to see if there was an increase in unsatisfactory specimens, ASC rate, and altered ASC:SIL ratio. Pap Tests (569,726) reviewed at the Cytopathology Laboratory of Women and Infants Hospital from 1998-2002 were included. TBS 1991 terminology was used through December 31, 2001. Conversion to TBS 2001 took place on January 1, 2002. The average ASC:SIL ratios pre- and postimplementation of TBS 2001 were 1.52:1 and 1.42:1, respectively. The rates of unsatisfactory specimens and ASC remained unchanged. Conversion to TBS 2001 did not adversely affect the ASC:SIL ratio or the detection rates of abnormalities of Pap tests.  相似文献   
36.
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
37.
38.
Postural effects on muscle nerve sympathetic activity in man   总被引:6,自引:4,他引:6       下载免费PDF全文
1. Pulse-synchronous bursts of multi-unit sympathetic activity (MSA) were recorded in peroneal muscle nerve fascicles in eight healthy subjects when lying, sitting and standing. The sympathetic activity was quantitated by counting the number of bursts in the mean voltage neurogram/min. Postural changes were analysed by considering the total activity to be a product of the number of bursts in relation to the number of heart beats (burst incidence) and the heart rate.2. In lying there were large interindividual differences in total activity, but for all subjects the activity increased when going from lying to sitting and from sitting to standing. With a few exceptions the increase between the lying and sitting postures was associated with an increase in both burst incidence and heart rate whereas between the sitting and standing postures there was an increase in heart rate but on the average no change in burst incidence.3. When going from lying to sitting or from sitting to standing the magnitude of the change in burst incidence was inversely related to the initial burst incidence so that subjects with low initial values usually showed greater increases in burst incidence than subjects with high initial values. Some subjects with high initial values decreased their burst incidence.4. With changes in postures there was an inverse linear relationship between the fraction of the change in MSA associated with a change in burst incidence and the fraction associated with a change in heart rate. An increase in total activity could be obtained by changing only burst incidence, by increasing heart rate without changing burst incidence, or by appropriate changes in both parameters. The slope of the regression line was -0.53 indicating that for adequate postural compensation fewer additional bursts were required when the compensatory response involved an increase in heart rate rather than an increase in only burst incidence.5. It is suggested that an impairment of the ability to regulate heart rate will make subjects with high burst incidence in the lying position orthostatically more vulnerable than those with low burst incidence.6. Shortly after standing up one subject developed bradycardia and subsequently fainted. The nerve recording was maintained until the subject collapsed. During the initial bradycardia no sympathetic bursts occurred suggesting that the syncope was associated with an interruption of normal baroreflex feedback between blood pressure and sympathetic outflow.  相似文献   
39.
The European Journal of Health Economics - In 2015, the Swedish government in an unprecedented move decided to allocate 150 million € to provide funding for new drugs for hepatitis C. This...  相似文献   
40.
Fibrodysplasia ossificans progressiva (FOP), a rare autosomal dominant disorder, is characterized by symmetrical congenital skeletal abnormalities and progressive heterotopic ossification of the connective tissues. At present, more than 300 years after the first report by Patin in 1648 in which he described the woman who turned to wood, its pathogenesis remains largely unknown and its therapy is limited to symptom-modifying trials. However, significant progress has been recently made and new data on the molecular organization and regulation of normal and disordered bone induction are likely to lead to a more specific therapy. FOP is believed to be a genetic disorder characterized by a disturbed expression of the endochondral osteogenesis programme, and the remarkable clues from the fly reported by Kaplan et al. [8] in 1990 suggest a gain-of-function mutation in the genetic regulation of bone morphogenetic proteins.  相似文献   
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