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71.
The nitric oxide pathway in pre-eclampsia: pathophysiological implications   总被引:2,自引:0,他引:2  
Pre-eclampsia, one of the most significant health problems inhuman pregnancy, complicates 6-7% of all gestations and is theleading cause of fetal growth retardation, infant morbidityand mortality, premature birth and maternal death. Recent researchimplicates free radicals in the pathophysiology of pre-eclampsia.This review covers the biochemistry of nitric oxide (NO) andpossible interactions with other free radicals. Studies in therat show that pregnancy is associated with enhanced productionand responsiveness to NO in both reproductive tissues and bloodvessels. Rats infused with NG-nitro-L-arginine methyl ester(L-NAME, a NO synthase inhibitor) have been used as an animalmodel of pre-eclampsia, and the effects of steroid hormoneson blood pressure in this model have been tested. Results suggestthat pre-eclampsia may be a state of NO deficiency. However,in humans there seem to be contradictions regarding the involvementof NO in maternal adaptation to pregnancy. It is suggested thatNO may be one of several systems that act in concert to maintaina symbiotic relationship between mother and fetus. However,the input of each system may be genetically determined.  相似文献   
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73.
培养心肌细胞牵张刺激装置的建立及应用   总被引:2,自引:2,他引:2  
1 方法 牵张刺激装置的制作如模式图 1.制作实验模型采用材料为有机玻璃板、2 4孔培养板、硅胶膜 (厚度 0 .2 2 μm) .硅胶膜从平面圆形变为球形时 ,面积扩大的百分比 =(S球 -S园 ) /S园 ,其中S球 =AD2 ,S园 =r2 ,而AD2 =h2 +r2 ,其中r为孔的半径 ,h为膜升高的高度图 2 .通过控制h的大小 ,可控制膜被牵拉的强度 .本实验采用使膜面积扩大 2 0 %的强度 ,故h =4mm[1] .参照Kassiri等[2 ,3 ] 方法进行心肌细胞的分离培养 .生长有贴壁心肌细胞的 2 4孔板被固定于牵张装置 ,缓慢充气使硅胶膜向上凸起 4mm ,分别维持…  相似文献   
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75.

Background

India accounts for approximately 10 million orthopaedically handicapped children and adults with limb deformity. Ilizarov ring fixator could treat most of these deformities.

Methods

Twenty cases of deformities of lower limb managed with Ilizarov technique during period between March 2001 and February 2003 were studied.

Results

55% were in the age group of 11-30 years. Out of the 20 cases studied, 6 were congenital talipes equino varus, 8 were fixed flexion deformity of knee, 4 were equines deformity of the ankle and 2 were malunited fracture shaft of tibia.4 patients who had recurrence were operated for fixed flexion deformity of the knee. The main complication encountered was pin tract infection, which was seen in 15(75%) cases. In 16(80%) cases, the results were excellent with no recurrence of deformity and patients were able to walk independently. In 4 (20%) cases, recurrence was mild to moderate (10 to 20) but all of them were able to ambulate idependently and carry out their routine activities.

Conclusion

Ilizarov ring fixator is a superior compared to conventional methods for correction of deformities of lower limb.Key Words: Ilizarov method, Ligamentotaxis, Distraction  相似文献   
76.
Aim  Worster-Drought syndrome (WDS), or congenital suprabulbar paresis, is a permanent movement disorder of the bulbar muscles causing persistent difficulties with swallowing, feeding, speech, and saliva control owing to a non-progressive disturbance in early brain development. As such, it falls within the cerebral palsies. The aim of this study was to describe the physical and neuropsychological profiles of children with WDS.
Method  Forty-two children with WDS (26 males, 16 females; mean age 7y 10mo, SD 3y 1mo; range 2y 6mo to 16y 5mo) were studied prospectively using a standard protocol.
Results  All of the children had severe bulbar dysfunction; 36 out of 42 had feeding difficulties and 23 of 38 had unintelligible speech, which was poorly compensated for by augmentative communication. There were accompanying disturbances in cognition (mean non-verbal IQ 59), behaviour (12/40 attention-deficit–hyperactivity disorder [ADHD]), social communication (8/42 autism), and epilepsy (12/39). The severity of bulbar dysfunction and impact of additional impairments made it difficult to use formal assessments.
Interpretation  WDS causes severe and persistent bulbar dysfunction that is often accompanied by additional impairments, as in other cerebral palsies. Speech prognosis is particularly poor. Early diagnosis with appreciation of the underlying neurology would encourage critical evaluation of interventions and long-term planning to improve outcome.  相似文献   
77.
Meniscal injuries: detection using MR imaging   总被引:15,自引:0,他引:15  
Both retrospective and blinded analyses of thin-section, high-resolution magnetic resonance (MR) images of the knee joint, produced using a solenoid surface coil, indicate that MR imaging is an effective technique for evaluating meniscal injuries. Images of 49 patients were evaluated, and the results were correlated with those of subsequent arthroscopy. A grading scale was developed to rate the index of suspicion of a meniscal tear based on the MR images. Overall, approximately 80% of menisci rated grade 4 (definite tear) or 3 (probable tear) were found to have corresponding tears at arthroscopy. In many other patients with a grade 4 or 3 meniscus in whom a corresponding tear was not found arthroscopically, meniscal tears at other sites or other abnormalities were correctly diagnosed using MR. A majority of the false-positive MR images involved the posterior horns of the menisci, the sites of most false-negative arthroscopic diagnoses. The predictive value of a negative MR image was almost 100%. Even in patients with moderate-to-large effusions, the menisci were accurately evaluated. The results imply that MR imaging is useful in the preoperative evaluation of suspected meniscal tears.  相似文献   
78.
We observed a human immunodeficiency virus (HIV)-infected homosexual male with AIDS related complex (ARC) who had a serum globulin level of 80 g/L. Serum protein electrophoresis revealed a gamma globulin fraction of 40 g/L, of which 50% (20 g/L) was contained within a paraprotein spike, comprised predominantly of IgG kappa. This patient also had high titer anti-HIV antibodies in his serum, which were Western blot reactive at a final dilution of 1:500,000, and recognized gp120env, p66pol, p55gag, p53pol, p41gag, and p24gag. Because paraproteins in the past have been shown to be directed against specific antigens, we purified this patient's paraprotein using a modified high performance liquid chromatography (HPLC)-hydroxylapatite procedure and tested the purified paraprotein for anti-HIV antibody activity. The purified paraprotein retained anti-HIV antibody activity to a final dilution of 1:100,000, and recognized p66pol, p55gag, p53pol, p41gag, and p24gag. The recognition of both "gag" and "pol" gene products suggested that the purified paraprotein might not be monoclonal in origin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that the purified paraprotein contained at least two immunoglobulin light chain species (Mol wt 30 to 33 Kd). Affinity chromatography of the purified paraprotein using a p24- Sepharose 4B matrix separated the "gag" and "pol" antibody activities. Immunoglobulin gene rearrangement analysis of a bone marrow aspirate (which contained 15% plasma cells) failed to reveal a clonal population of immunoglobulin producing cells. We conclude that this patient's paraprotein accounted for most of the anti-HIV activity present in whole serum, and that this paraprotein was not monoclonal in origin.  相似文献   
79.
Background  Palmoplantar pustulosis (PPP) discloses some differences compared to vulgar psoriasis (PV) in terms of age of onset, female predominance and low occurrence of psoriasis lesions elsewhere. Cigarette smoking has been associated to PPP in international studies; nevertheless, these studies were never performed among Brazilian.
Objectives  To compare prevalence of smoking among PPP, PV and other dermatologic patients (NPD).
Methods  Case–control study involving 25 PPP patients from a reference psoriasis centre. Two control groups were matched according to gender and age: 50 patients with PV and 50 NPD. Confounders were adjusted by conditional multiple logistic regression.
Results  Among cases, 84.0% were female and PPP age of disease onset (41.4 years) was greater than PV (34.5 years). Prevalence of ever smoking was higher among cases (92.0%) than PV (52.0%) and NPD (30.0%). Adjusted odds ratio of PPP ever smoking compared to PV and NPD was 9.5 and 36.2, respectively. All smokers reported the onset of their habit before the development of PPP.
Conclusions  There was significant association between PPP and smoking. However, the impact of giving it up in the clinical course of the disease remains to be established.  相似文献   
80.
Many human globin-chain mutants contain amino acid replacements that result from single base changes in the corresponding globin gene. Using recombinants, the coding sequences of each of the alpha-, beta-, Ggamma- , and Agamma-globin genes have now been determined. Those sequences of DNA that are cleaved by a number of specific restriction endonucleases have been identified and accurately positioned. Mutations at these sequences abolish the restriction site, and therefore, the pattern of DNA fragments containing hybridizing globin-gene sequences is altered compared to DNA from normal persons. This allows the identification of one of a pair of cross-hybridizing human globin-gene sequences, as is shown here for the two alpha-globin, the two gamma-globin, and the delta- and beta-globin genes.  相似文献   
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