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81.
OBJECTIVE: To evaluate radiographically the humeroulnar (HU) and humeroradial (HR) joint spaces in patients with long-term rheumatoid arthritis (RA). METHODS: An inception cohort of 74 patients with RA were followed for 15 yr. At the end-point, 148 elbows were radiographed by a standard method. The HU and HR joint spaces were examined from the anteroposterior radiographs by measuring the shortest tangential distance in the middle of the joints. Destruction of the elbow joints, assessed with the Larsen method on a scale of 0-5, was studied in relation to the joint-space measurements. RESULTS: Mean (s.d.) HU joint space (n=148) in RA patients was 2.5 (1.1) mm, range 0-4 mm [2.9 (0.8) mm in men and 2.4 (1.1) mm in women]. Mean (s.d.) HR joint space (n=140) was 2.3 (0.9) mm, range 0-4 mm [2.5 (0.8) mm in men and 2.3 (1.0) mm in women]. HU and HR spaces of the affected joints (Larsen grades 2-5) [1.9 (s.d. 1.1) and 1.8 (0.9) mm respectively] were notably narrower than those of the unaffected (Larsen grades 0-1) joints [3.1 (0.7) and 2.9 (0.6) mm]. All the joints graded as Larsen 4 or 5 (n=13) had a value of 0 mm for both joint spaces. Both the HU and the HR joint-space narrowing was associated with increasing destruction (Larsen grading) of the joint. [r= -0.69 (95% CI -0.77 to -0.60) and r= -0.70 (-0.78 to -0.60)]. The monotonic narrowing was significantly increasing from unaffected (Larsen 0, 1), slightly (2), moderately (3) to severely (4, 5) affected joints (P<0.001). A step in this process occurred between Larsen grades 3 and 4, when the mean joint space diminished from 1.4 and 1.5 respectively to 0 mm. CONCLUSIONS: Joint-space narrowing is a frequent consequence of rheumatoid affection of the elbow joint. HR joint space decreases together with HU joint space; however, the HR joint space is already slightly narrower at the start. The narrowing is a rather late phenomenon, occurring only after erosive destruction. This should be borne in mind when using the Larsen method to evaluate changes in the elbow joint.  相似文献   
82.
肾康片质量标准的研究   总被引:4,自引:0,他引:4  
目的:研究肾康片的质量标准并控制该制剂的质量。方法:用薄层色谱法鉴别了肾康片中的黄芪,山茱萸,桑寄生及丹参,用薄层色谱法限量检查屯该制剂中的乌头碱,用双波长薄层扫描法测定了该制剂中黄芪甲苷的含量。结果:乌头碱限量符合中国药典测定,黄芪甲苷的平均回收率为97.5%,其RSD为1.43%。结论:本文的结果显示出这些方法可用于控制该制剂的质量,方法灵敏,简便,专属,准确。  相似文献   
83.
Cervical myelography: survey of modes of practice and major complications   总被引:2,自引:0,他引:2  
Robertson  HJ; Smith  RD 《Radiology》1990,174(1):79-83
A total of 68 major complications of cervical myelography were reported by 220 neuroradiologists in a mail survey. Two-thirds of the complications were attributed to cervical spine hyperextension and one-third to lateral C1-2 puncture. Narrow sagittal diameter of the spinal canal and severe cervical spondylosis were frequent contributing factors to hyperextension injury of the cervical spinal cord. Clinical and radiographic premyelography screening is suggested, with magnetic resonance imaging performed first in patients with spinal canal stenosis, severe spondylosis, and/or myelopathy of any cause. Neck extension should be minimal during myelography. All C1-2 punctures should be monitored with lateral fluoroscopy for accurate needle positioning and prevention of contrast medium injection into the spinal cord.  相似文献   
84.
Objective: To compare erector spinae muscle (ESM) activity as measured by surface electromyography (SEMG) in lumbar flexion from the upright position in men with ankylosing spondylitis (AS) and healthy males, and to study associations between pain, lumbar mobility and ESM activity. Methods: Surface EMG was undertaken at the L1-2 and L4-5 levels in 11 men with AS taking part in a rehabilitation course at the Rheumatism Foundation Hospital, and in 10 pain-free male controls, while the subjects were bending forward. Results: During full flexion ESM SEMG activity was significantly greater in patients with AS than in the controls. Relaxation was evident during flexion in all of the controls but in only some patients with AS. Lumbar mobility correlated negatively with ESM activities. No relationship between pain and ESM activity was evident. Some AS patients reported pain while ESM activity was being measured. Conclusion: Decreased lumbar mobility rather than pain explains ESM activity during full flexion in patients with AS.  相似文献   
85.
86.
Almost all primary retroperitoneal liposarcomas can be classified as well-/dedifferentiated liposarcoma. Rarely, however, primary retroperitoneal liposarcoma is classified as myxoid/round cell liposarcoma, based on the presence of myxoid areas and vascular crow's feet pattern, which has resulted in a debate on the classification of liposarcoma in the retroperitoneum. Genetically, myxoid/round cell liposarcoma and well-/dedifferentiated liposarcoma are different diseases. Myxoid/round cell liposarcoma is characterized by a translocation causing FUS-CHOP or EWSR1-CHOP fusion, whereas well-/dedifferentiated liposarcoma is characterized by an amplification of the 12q13-15 region, including MDM2 and CDK4 genes. As myxoid/round cell liposarcoma is highly radio- and chemosensitive, differentiation between subtypes is important to optimize treatment. We studied whether primary retroperitoneal liposarcomas diagnosed as myxoid/round cell liposarcoma represent molecularly true myxoid/round cell liposarcoma or are histopathological mimics and represent well-/dedifferentiated liposarcoma. Primary retroperitoneal myxoid/round cell liposarcoma (n=16) were compared to primary extremity myxoid/round cell liposarcoma (n=20). Histopathological and immunohistochemical features were studied. Amplification status of the 12q13-15 region was studied using a multiplex ligation-dependent probe amplification analysis, and FUS-CHOP or EWS-CHOP translocations were studied using RT-PCR. In primary retroperitoneal myxoid/round cell liposarcoma, MDM2 and CDK4 staining was both positive in 12 of 15 cases. In primary extremity myxoid/round cell liposarcoma, MDM2 was negative in 18/20 and CDK4 was negative in all cases. Multiplex ligation-dependent probe amplification showed the amplification of 12q13-15 region in 16/16 primary retroperitoneal myxoid/round cell liposarcomas and in 1/20 primary extremity myxoid/round cell liposarcomas. Translocation was present in all (18/18) primary extremity myxoid/round cell liposarcomas, but absent in all primary retroperitoneal myxoid/round cell liposarcomas. On the basis of immunohistochemical and molecular characteristics, apparent primary retroperitoneal myxoid/round cell liposarcoma can be recognized as well-/dedifferentiated liposarcoma with morphological features mimicking myxoid/round cell liposarcoma. In these cases, treatment should probably be specifically designed as for well-/dedifferentiated liposarcoma. Moreover, finding of myxoid/round cell liposarcoma translocations in a retroperitoneal localization is highly suggestive of metastasis and should prompt search for a primary localization outside the retroperitoneum.  相似文献   
87.
88.
Abstract: Clodronate, pamidronate and etidronate are commonly used bisphosphonates, which accumulate extensively in arteries and some other tissues. We compared their pharmacokinetics in rabbits with those of tiludronate, the drug newly introduced to clinical use. The 14C-labelled drugs were given intravenously and plasma drug levels were monitored for up to 24 hr. The dose-related plasma concentrations of tiludronate and etidronate were clearly higher and decreased more slowly than those of clodronate and pamidronate (P<0.001). Already at 5 min., the concentrations of tiludronate and etidronate were higher than those of clodronate and pamidronate (P=0.016). At 24 hr, plasma concentration of tiludronate was 12±6.6%, of etidronate 18±2.5%, of clodronate 0.8±0.2%, and of pamidronate 1.4±0.4% of the dose per body weight. With the same dose (25 mg/kg), absolute AUC0–24hr for tiludronate and etidronate was 9–11 times larger than for clodronate. AUC0–24hr for pamidronate (2.5 mg/kg) was 11% of that for clodronate. Plasma clearance of tiludronate and etidronate was 9–15 times slower than that of clodronate and pamidronate. At 24 hr, the mean tissue-to-plasma ratio of tiludronate for aorta was 1.2–1.6. For bone, spleen, liver and kidneys the ratio varied from 5.4 to 52.6. The results suggest that 1) tiludronate and etidronate are removed from plasma much slower than clodronate and pamidronate, and 2) the potential of tiludronate to concentrate in arteries and bone is generally smaller than previously found with the other bisphosphonates.  相似文献   
89.
OBJECTIVE: To assess whether serum C-terminal cross-linking telopeptide of type I collagen (ICTP), a marker of type I collagen degradation, has any additional value in the assessment of treatment effect in patients with early rheumatoid arthritis (RA). METHODS: A total of 182 patients were randomized to treatment either with three disease-modifying anti-rheumatic drugs (DMARDs) and low-dose prednisolone (COMBI) or with a single DMARD with or without low-dose prednisolone (SINGLE). We investigated the prognostic value of serum ICTP level for the progression of joint destruction in X-rays (Larsen's score) from baseline to 2 years. RESULTS: There was a statistically significant decrease in serum ICTP levels from baseline to 1 year. At 6 months, the serum ICTP level was lower in the COMBI patients compared to that of the SINGLE cases (p = 0.008, after adjustment for baseline ICTP). When grouping the patients according to serum ICTP tertiles at 6 months, there was a statistically significant trend for increasing median change in Larsen score from baseline to 2 years from lowest to highest ICTP tertile in the SINGLE patients [p = 0.008, after adjustment for 28-joint Disease Activity Score (DAS28) score and RF status at baseline], while in the COMBI, the change remained low in all ICTP tertiles. CONCLUSIONS: The COMBI strategy for recent-onset RA results in early suppression of type I collagen degradation, which is reflected in radiological joint damage at 2 years. Serum ICTP at 6 months may be useful for identifying those RA patients whose treatment should be intensified to prevent further joint damage.  相似文献   
90.
目的:探讨谷氨酸对脑组织即早基因表达的影响以及醋酸锌对谷氨酸诱导c-fos和c-jun过度表达的拮抗作用。方法:体外小鼠海马脑片培养;在培养基中加入200μmol/L的谷氨酸(或同时加入谷氨酸和醋酸锌),作用0.5,1,2,3h,然后进行RT-PCR实验,检测c-fos和c-jun的表达变化。结果:200μmol/L谷氨酸处理的脑片中,1-2h期间c-fos的表达升高,当谷氨酸与100μmol/L醋酸锌共同处理脑片时,1-3h期间c-fos表达基本恢复正常;200μmol/L谷氨酸作用下,脑片c-jun表达水平从0.5h起即明显升高,谷氨酸与醋酸锌共同作用时,可见c-jun基因在各检测时段表达基本接近正常。结论:谷氨酸可引起c-fos及c-jun的过度表达,锌离子可拮抗谷氨酸诱导的c-fos和c-jun过度表达作用,使二基因表达恢复正常。  相似文献   
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