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Background  

The aims of this study were to examine the extent to which higher intellectual abilities protect higher socio-economic groups from functional decline and to examine whether the contribution of intellectual abilities is independent of childhood deprivation and low birth weight and other socio-economic and developmental factors in early life.  相似文献   
3.
We describe a 24-year-old man who presented with unilateral sacroiliac pain associated with constitutional symptoms. Subsequent biopsy and pathohistologic evaluation demonstrated Ewing's sarcoma. We emphasize a consideration of Ewing's sarcoma in the differential diagnosis of unilateral sacroiliac pain.  相似文献   
4.
Previous reports in the literature have described correlation of increasing repeat length with severity of the phenotype, in Kennedy syndrome. We describe male siblings with different repeat lengths, with lack of expression of the phenotype in the sibling with the longer repeat length. The phenotype was identical to motor neurone disease. There is variability of expression in Kennedy syndrome and repeat length even in siblings cannot be taken as a conclusive indicator of severity. CAG repeat length cannot be used to predict the natural history of Kennedy disease. The diagnosis of Kennedy syndrome should be considered in male patients presenting with atypical motor neurone disease.  相似文献   
5.
Adult polycystic liver disease is an entity that is striking for the presence of extraordinary hepatomegaly. Very rarely do patients under 40 years of age experience problems and only a minority of middle-aged patients manifest symptoms due to organ compression or biliary tree obstruction. The clinical course is usually benign, and no specific therapy is required. The onset of right upper quadrant pain, back pain, and shortness of breath prompted evaluation of a 32-year-old woman with progressive hepatomegaly. CT scan revealed a massive cyst-riddled liver with posterior displacement of the spleen, compression of the pancreas, and renal cysts. Prothrombin time, albumin, and liver enzyme values were normal except for a mildly elevated gamma-glutamyl transpeptidase.  相似文献   
6.
SUMMARY The interferons are natural glycoproteins secreted in response to various stimuli, including viral infection. They have antiviral, antiproliferative and immunomodulatory effects on different target cell populations. Since recombinant human interferons have become available, they have been tested in a wide range of malignancies. They are well established in the treatment of hairy cell leukaemia, chronic myelogenous leukaemia and multiple myeloma. Although they have documented activity against lymphoma, melanoma, renal cell cancer and carcinoid tumours, their role in the treatment of these tumours is less clear. In the common solid tumours, such as lung cancer and colorectal cancer, the use of interferons remains experimental. Here we will summarise their practice applications in oncology, using randomised studies where available to establish their place in multi-modality treatment. We will not discuss their use as antiviral or immunomodulating agents in viral and autoimmune diseases, multiple sclerosis or after organ transplantation.  相似文献   
7.
We conducted an incidence study to determine the occurrence rates of clear cell adenocarcinoma (CCAC) of the vagina and cervix in young women (born in 1940 and thereafter), and a case-series analysis, focusing on the maternal history of pregnancy and delivery and in-utero exposure to diethylstilbestrol (DES). Overall, 10 cases of CCAC had been listed in the files of the Connecticut State Tumor Registry prior to the study, and each of the 10 cases were confirmed as valid. In addition, another 10 cases, all previously undetected, were found after the tissue slides of young women listed as having other cancers of the vagina and cervix were reviewed by expert pathologists, suggesting that prior estimates of the incidence rate for CCAC must be misleading unless special efforts are taken to identify undetected cases. The incidence rates of vaginal CCAC (11 cases total) were highest in 1975-1979, and decreased slightly during 1980-1982. In the cervix (nine cases total), the rate increased consistently since 1970. History of in-utero exposure to diethylstilbestrol was obtained for five of eight vaginal cases and four of eight cervical cases of CCAC. In all nine cases, exposure to diethylstilbestrol was associated with a history of bleeding during the pregnancy or prior miscarriage. We conclude that the finding of stable (or rising) incidence rates for CCAC occurring nearly 30 years after the marked decrease in diethylstilbestrol sales emphasizes the need for continued clinical and epidemiologic studies of the etiology and clinical course of CCAC.  相似文献   
8.
Chronic low back pain: comparison of bone SPECT with radiography and CT   总被引:1,自引:0,他引:1  
Ryan  PJ; Evans  PA; Gibson  T; Fogelman  I 《Radiology》1992,182(3):849
  相似文献   
9.
Uroscopy in the 21st century: high-field NMR spectroscopy   总被引:1,自引:1,他引:0  
From the experiments described, it can be seen that there are different research approaches that can be taken and these are summarized in Table 1. Whereas much scientific research is principally hypothesis led, there remains, nevertheless, an important place for exploratory research. High resolution NMR can measure, directly and simultaneously, a wide range of endogenous metabolites in biological fluids and has the unique capability of providing structural information on the metabolites detected. It has proved to be a powerful research tool with which to study inherited metabolic diseases, renal disease, drug metabolism, and toxicity, and can be used to monitor the effects of drug therapy. For instance, by using a library of experimental toxins one can map the metabolic profile of site-specific nephron injury. With this approach in man one could eventually take an unknown disease such as Balkan nephropathy and predict the initial site of tubular injury, the mode of injury and therefore the kind of toxin capable of producing that injury. NMR spectroscopic techniques are still advancing rapidly, with ever increasing sensitivity and sophistication of NMR pulse sequences to enhance structural elucidation in complex mixtures. Given the advances in directly coupled HPLC-NMR and even HPLC-NMR-mass spectroscopy it is likely that these technologies in conjunction with pattern recognition will make major contribution to our understanding of renal processes and provide new diagnostic insights in the 21st century.   相似文献   
10.
Leukotriene B4 (LTB4) and the protein kinase C activator, 4-beta-phorbol dibutyrate (PDBu), both induced a pronounced and concentration-dependent stimulation of hydrogen peroxide (H2O2) generation by purified guinea pig peritoneal eosinophils in the concentration range 1 nM-1 microM. The LTB4 response was inhibited competitively by the specific LTB4 receptor antagonist, U-75302, with a KB of 25 nM, while the concentration-response curves for both stimuli were shifted rightwards (3.8-fold and 2.8-fold for LTB4 and PDBu, respectively) by the competitive protein kinase C inhibitor, 1-O-hexadecyl-2-O-methylglycerol at a concentration of 300 microM. LTB4 appears, therefore, to induce respiratory burst in eosinophils via a receptor-mediated mechanism involving protein kinase C.  相似文献   
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