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131.
SUMMARY Intracranial tuberculoma has become a rarity. It remains a curable lesion that responds well to medical therapy. Although diagnosis in developed countries is often made only postoperatively, early and effective treatment can be instituted if a high index of suspicion is maintained and diagnostic criteria are looked for. A case is presented which illustrates the difficulties in reaching a diagnosis, and a review of the literature is given.  相似文献   
132.
We report the third case in the literature of a hobnail haemangioma with cyclic changes throughout the menstrual cycle in a 36-year-old woman, suggesting a hormonal basis for the variations in the tumour. This patient was under oral contraceptive treatment due to ovarian endometriosis, making the clinical diagnosis difficult.  相似文献   
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BACKGROUND: We investigated whether systemic chemotherapy increased episodes of acute pyelonephritis (APN) in patients with an indwelling double-J stent due to non-urological malignant ureteral obstruction. METHODS: A retrospective study was performed on a total of 74 patients (16 men and 58 women; median age, 53.0; range, 34-84 years) with non-urological malignant ureteral obstruction, who were managed by double-J stenting between October 1997 and December 2001. The patients were divided into those who received (33 patients, group I) and those who did not receive systemic chemotherapy (41 patients, group II) during the stent indwelling period (median, 7.0; range, 1-44 month). Routine antibiotic prophylaxis was not administered to any patient. Median follow-up was 10.5 (range, 1-45) months. Clinical features, including the incidence of febrility and APN, were compared between the two groups. RESULTS: Of the 74 patients, 18 patients (24.3%) experienced acute febrile episodes during ureteral stenting, but only five (6.8%) patients were diagnosed as having APN. No significant difference in the incidence of fever or APN was found between the two groups (P = 1.000 and P = 0.651, respectively). Univariate logistic analysis indicated that only the duration of follow-up was a risk factor for an episode of fever. Other parameters had no clinical significance. CONCLUSION: Our findings suggest that systemic chemotherapy may not predispose the risk of acute pyelonephritis in patients with an indwelling ureteral stent due to non-urological malignant ureteral obstruction.  相似文献   
135.
Practising physicians, faced with pressure to control healthcare costs, are increasingly being asked to incorporate considerationsof cost into their decisions regarding the care they offer theirpatients. Accordingly, it is of importance to know how the moneyis spent. The use and cost of X-rays in family practice, andwhat factors influence it, is not well known. The aim of thisstudy is to analyse the use and the cost of X-ray requests infamily practice. A prospective practice study from 16 Icelandiccommunity health centres (HC) with computerised contact dataand their target populations, 12 rural and four urban, was carriedout. The X-ray requests, numbers, types and cost were analysed.Patient and practice characteristics were used to assess variationin X-ray practices. A total of 5173 X-ray requests were recorded,which comprised 3.2% of all office visits. The mean number ofX-ray requests was 24.7 and 14.7/1000 contacts in rural andurban HCs respectively, and 123.1/1000 inhabitants in ruralHCs. The X-ray request rate per individual increased with age,but per contact it was highest among young males. Extremityand chest X-rays were the most common requests. For every 1000individuals added to a practice population, the likelihood ofhaving an X-ray requested decreased by 18%. The use of X-rayexaminations in family practices represents approximately 17%of all ambulatory X-ray use in Iceland. The calculated costof X-rays requested in this study was $6157/1000 inhabitantsper year as of October 1993. The rate of X-rays requested differsgreatly among doctors, which indicates potential for savingsin the health care system, through radiology guidelines. Thisstudy indicates that the rate and the cost of X-rays are lowin general practice in Iceland. X-ray facilities should be adequateand accessible to each practice. The results of this study areuseful in quality control, organisation and in the analysisof cost in the health care system. Training of family doctorsneeds to take this information into account.  相似文献   
136.
Most axons in the CNS innervate specific subregions or layers of their target regions and form contacts with specific types of target neurons, but the molecular basis of this process is not well understood. To determine whether collapsin-1/semaphorin-III/D, a molecule known to repel specific axons, might guide afferent axons within their cerebellar targets, we characterized its expression by in situ hybridization and observed its effects on mossy and climbing fiber extension and growth cone size in vitro. In newborn mice sema-D is expressed by cerebellar Purkinje cells in parasagittal bands located medially and in some cells of the cerebellar nuclei. Later, sema-D expression in Purkinje cells broadens such that banded expression is no longer prominent, and expression is detected in progressively more lateral regions. By postnatal day 16, expression is observed throughout the cerebellar mediolateral axis. Collapsin-1 protein, the chick ortholog of sema-D, did not inhibit the extension of neurites from explants of inferior olivary nuclei, the source of climbing fibers that innervate Purkinje cells. In contrast, when it was applied to axons extending from basilar pontine explants, a source of mossy fiber afferents of granule cells, collapsin-1 caused most pontine growth cones to collapse, as evidenced by a reduction in growth cone size of up to 59%. Moreover, 63% of pontine growth cones arrested their extension or retracted. Its effects on mossy fiber extension and its distribution suggest that sema-D prevents mossy fibers from innervating inappropriate cerebellar target regions and cell types.  相似文献   
137.
How to use Chlamydia antibody testing in subfertility patients   总被引:1,自引:9,他引:1  
Screening for tubal factor subfertility by means of Chlamydia antibody testing (CAT) was introduced into the initial work-up of subfertile couples several years ago. The results reported, however, are heterogeneous, and no uniformity exists in cut-off levels of titres, or in definitions of tubal factor subfertility. We performed a prospective cohort study to evaluate the implications of varying the definitions of tubal pathology and of modifying the cut-off levels on the clinical impact of CAT in predicting tubal factor subfertility. In 227 consecutive patients who attended our fertility clinic, the Chlamydia IgG antibody titre was determined and related to tuboperitoneal abnormalities at laparoscopy as a reference standard. According to received operating characteristic (ROC) curve analysis, a titre of 16 is the optimum cut-off level. Increasing the cut-off level improves specificity and positive likelihood ratio (LR+), at the expense of sensitivity and negative LR (LR-). Changing the definition of tubal factor subfertility from unspecified tuboperitoneal abnormalities into extensive adhesions and/or bilateral distal tubal occlusion improves LR+, LR- and kappa significantly. We conclude that CAT is more accurate in predicting severe distal tubal pathology than unspecified tuboperitoneal abnormalities. Although from a statistical point of view a titre of 16 is the optimum cut-off level, from a clinical point of view 32 or 64 may be preferable, depending on the aim of screening and the inception cohort.   相似文献   
138.
We have previously shown that activated C1s complement and activated T cells cleave beta2-microglobulin (beta2m) in vitro leading to the formation of desLys58 beta2m. This process can specifically be inhibited by C1-esterase inhibitor (C1-inh). Furthermore we showed that exogenously added desLys58 beta2m in nanomolar amounts to a one-way allogenic mixed lymphocyte culture (MLC) increased the endogenous production of IL-2 and the generation of allo-specific cytotoxic T lymphocytes. C1-inh was purified from fresh human plasma and added to human or murine MLC and mitogen-stimulated lymphocyte cultures grown in the presence of complement-inactivated serum. Read-outs were cell proliferation, lymphokine production and development of T cell-mediated cytotoxicity. We found that addition of C1-inh to MLC and mitogen- exposed murine and human lymphocyte cultures inhibited proliferation, the development of allospecific cytotoxic activity, and changed the endogenous production of IL-2, IL-4, IL-10, IL-12 and IFN-gamma. These data clearly demonstrate a regulatory function of C1-inh on T cell- mediated immune functions.   相似文献   
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