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排序方式: 共有2325条查询结果,搜索用时 15 毫秒
1.
The purpose of this study was to evaluate three subcutaneous injection sites for low-dose heparin therapy (5,000 units). One hundred and one subjects were randomly placed in one of three groups. Group A received injections in the abdomen, Group B, in the thigh, and Group C in the arm. Each subject received three injections at the one site. Activated partial thromboplastin time (APTT) was measured prior to initiation of heparin and again four hours after the first injection. Bruising was measured at 48, 60, and 72 hours postinjection. There were no statistically significant differences among groups for either changes in APTT or bruising at 60 and 72 hours postinjection. Thus the clinical practice of utilizing the abdomen as the only or preferred site for subcutaneous heparin injections was not supported. 相似文献
2.
This monograph reviews the literature regarding therapy for childhood idiopathic thrombocytopenic purpura (ITP). The role and mechanism of action are discussed for corticosteroids, splenectomy, and intravenous gamma globulin. Alternative therapies with potent immunosuppressive agents are also mentioned. Guidelines for the management of children with ITP are presented. 相似文献
3.
This study evaluated the performance of a synthetic implant material, Hard Tissue Replacement Polymer, for: (1) ease of handling, (2) compatibility with bone and soft tissue, (3) stability of augmentation over time, and (4) development of untoward effects. HTR (a registered trademark of HTR Sciences, a division of United States Surgical Corporation, Norwalk, CT 06856) was implanted into 34 patients by means of five different surgical procedures. The material was found to be easy to manipulate during surgery. Tissue and bone compatibility, defined as absence of inflammation, was present in 32/34 surgical sites (94%). In extraction sites during the 18-month follow-up, no measurable decrease in bone height or width was seen. One patient with a large periodontal endodontic defect developed a post-operative infection necessitating extraction of the tooth. No induction of bone was seen in response to placement of HTR material. 相似文献
4.
5.
INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA 总被引:1,自引:0,他引:1
SY Chen WC Wu CJ Tseng JS Kuo CY Chai 《Clinical and experimental pharmacology & physiology》1997,24(1):46-56
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain. 相似文献
6.
Hillmann JS; Mesgarzadeh M; Revesz G; Bonakdarpour A; Clancy M; Betz RR 《Radiology》1987,165(3):769-773
Proximal femoral focal deficiency, an uncommon congenital anomaly, necessitates early radiologic classification for surgical planning and treatment. Objective radiographic criteria, including femoral length index, acetabular depth index, acetabular angle index, and shape of the proximal femur were determined in 49 patients before cartilaginous ossification of the femoral capital epiphysis; final classification was based on follow-up radiographs or findings at arthrography or surgery. These parameters were analyzed to determine the accuracy and contributions of each in classification. Correct classification into one of three groups was possible in 86% of cases with use of three of the parameters: femoral length index, acetabular depth index, and shape of the proximal femur. The acetabular angle was found to contribute insignificantly to classification. Magnetic resonance imaging, used in only one case, depicted the nonossified cartilaginous femoral capital epiphysis, thus obviating the need for invasive diagnostic procedures and facilitating early classification. 相似文献
7.
Comparative testicular toxicity of bis(2-methoxyethyl) ether and 2-methoxyethanol in rats 总被引:2,自引:0,他引:2
Male rats were exposed to 0, 110, 370, or 1100 ppm bis(2-methoxyethyl)ether (diglyme) 6 h/day, 5 days/week for 2 weeks. One group of male rats was exposed to 300 ppm 2-methoxyethanol (2-ME) for 2 weeks as a positive control. Exposed rats were killed after 10 days of exposure and 14, 42, or 84 days post-exposure (PE), respectively. At 110 ppm diglyme, spermatocytes in pachytene and meiotic division at spermatogenic stages XII-XIV were mainly affected. At 370 ppm diglyme, affected germ cells were similar to those seen at 110 ppm diglyme, but round spermatids at spermatogenic stages I-VII were also affected. The testes regained normal spermatogenesis by 84 days PE. At 1100 ppm diglyme or 300 ppm 2-ME, marked testicular atrophy was found affecting all spermatogenic stages. Damaged seminiferous tubules were lined with regenerating pachytene spermatocytes at 14 days PE and with spermatocytes and round spermatids after 42 days PE. Most but not all testes in rats exposed to 300 ppm 2-ME or 1100 ppm diglyme had normal morphology after 84 days PE. Based on the observation of germ cell damage, spermatozoa population in the epidymal tubules, reversibility of spermatogenesis after various PE periods, testicular toxicity induced by 300 ppm 2-ME was more severe than that seen at 370 ppm diglyme but was slightly less remarkable than that of 1100 ppm diglyme. 相似文献
8.
9.
Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients 总被引:1,自引:1,他引:0
al-Wakeel JS; Mitwalli AH; Huraib S; al-Mohaya S; Abu-Aisha H; Chaudhary AR; al-Majed SA; Memon N 《Nephrology, dialysis, transplantation》1997,12(7):1420-1424
High serum fluoride (F-) in patients with chronic renal failure (CRF) and
end-stage renal disease (ESRD) is associated with risk of renal
osteodystrophy and other bone changes. This study was done to determine F-
in normal healthy controls and patients with ESRD on haemodialysis (HD) or
peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females)
and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in
the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l)
of F- content in drinking water. Control subjects showed a mean serum F-
concentration of 1.08 +/- 0.350 microM/l. Males in control group showed
slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than
females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F-
concentration did not correlate significantly with age and sex among
control subjects, whereas such correlation was observed in patients with
ESRD on dialysis. Mean serum F- concentration was significantly higher in
patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal
controls. When grouped according to sex, the mean serum F- concentration in
males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than
females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped
according to age, it was observed that F- concentration was significantly
higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with
age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated
with age and sex, being higher in males and above 20 years. Despite
appreciable clearance of F- (39-90%) across the peritoneum, patients on
CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs
2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their
serum F- concentration above 3.0 microM/l, posing the risk of renal
osteodystrophy.
相似文献
10.
Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2