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91.
Molecular and supramolecular diversity may be generated, respectively, by reversible, covalent or noncovalent self-assembly of basic components whose various potential combinations in number and nature represent a virtual combinatorial library. This concept is applied to the induction of inhibitors of carbonic anhydrase (CA) by reversible recombination of aldehyde and amine components. It is found that the presence of CA favors the formation of those condensation compounds that may be expected to present the strongest binding to the CA active site. The virtual combinatorial library approach may represent a powerful methodology for the discovery of substrates, inhibitors, receptors, catalysts, and carriers for a variety of processes.  相似文献   
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Objective

We aimed to explore the impacts of new vaccine introductions on immunization programmes and health systems in low- and middle-income countries.

Methods

We conducted case studies of seven vaccine introductions in six countries (Cameroon, PCV; Ethiopia, PCV; Guatemala, rotavirus; Kenya, PCV; Mali, Meningitis A; Mali, PCV; Rwanda, HPV). Interviews were conducted with 261 national, regional and district key informants and questionnaires were completed with staff from 196 health facilities. Routine data from districts and health facilities were gathered on vaccination and antenatal service use. Data collection and analysis were structured around the World Health Organisation health system building blocks.

Findings

The new vaccines were viewed positively and seemed to integrate well into existing health systems. The introductions were found to have had no impact on many elements within the building blocks framework. Despite many key informants and facility respondents perceiving that the new vaccine introductions had increased coverage of other vaccines, the routine data showed no change. Positive effects perceived included enhanced credibility of the immunisation programme and strengthened health workers’ skills through training. Negative effects reported included an increase in workload and stock outs of the new vaccine, which created a perception in the community that all vaccines were out of stock in a facility. Most effects were found within the vaccination programmes; very few were reported on the broader health systems. Effects were primarily reported to be temporary, around the time of introduction only.

Conclusion

Although the new vaccine introductions were viewed as intrinsically positive, on the whole there was no evidence that they had any major impact, positive or negative, on the broader health systems.  相似文献   
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The aim of this study is to assess the long-term effectiveness and safety of IL1Ra in Schnitzler syndrome (SchS). Between 2010 and 2012, we performed a nationwide survey among French internal medicine departments to identify SchS patients. We retrospectively analyzed the long-term efficacy and safety of IL1Ra and the outcome of patients that did not receive this treatment. Forty-two patients were included in the study, 29 of whom received IL1Ra. The mean age at disease onset was 59.9 years. Disease manifestations included urticaria (100%), fever (76%), bone/joint pain (86%), bone lesions (76%), anemia (67%), and weight loss (60%). The monoclonal gammopathy was overwhelmingly IgM kappa (83%). The mean follow-up was 9.5 years (range: 1.6-35). Two patients developed Waldenström's macroglobulinemia and one developed AA amyloidosis. All of the 29 patients who received IL1Ra responded dramatically. After a median follow-up of 36 months (range: 2-79), the effectiveness remained unchanged. All patients remained on anti-IL-1 therapy. Twenty-four patients (83%) went into complete remission and five (17%) into partial remission. Three patients experienced grade 3-4 neutropenia. Six patients developed severe infections. No lymphoproliferative diseases occurred while on IL1Ra. When last seen, all patients without anakinra had an active disease with variable impact on their quality of life. Their median corticosteroids dosage was 6 mg/d (range: 5-25). IL1Ra is effective in SchS, with a sharp corticosteroid-sparing effect. Treatment failures should lead to reconsider the diagnosis. Long-term follow-up revealed no loss of effectiveness and a favorable tolerance profile. The long-term effects on the risk of hemopathy remain unknown.  相似文献   
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Posterior reversible encephalopathy syndrome (PRES) is characterized clinically by headaches, seizures, vomiting, nausea, visual abnormalities, and altered mental function and is often (but not invariably) accompanied by parieto-occipital imaging features. The aim of this study is to describe the clinical and radiological features and outcome following PRES in a paediatric cohort. From a retrospectively identified cohort, case records were studied to confirm a diagnosis of PRES. Neuroimaging was reviewed again to assign to recently described radiological subtypes parieto-occipital pattern, holohemispheric watershed pattern, dominant superior frontal sulcus pattern, and asymmetrical or partial expression of the three primary patterns (A/P). Patient outcome was measured by the modified Rankin scale (mRS) scores. Nine boys and three girls with mean age of 12 were identified. Hypertensive episodes (n?=?11), tacrolimus toxicity (n?=?4), and autoimmunity (n?=?1) were identified as potential risk factors/etiologies. Their median mRS at the peak of illness was 2 (range 2–5); three children required intensive care support. After mean follow-up of 35 months (median 37 months; range 3–60 months), all patients improved significantly with mean mRS of 1 (median 1; range 0–1). Conclusion: PRES is easily recognizable by the clinical and radiological features. Although severe at presentation, the outcome from this condition is favorable.  相似文献   
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A wide range of genitourinary pathologies can be diagnosed in utero, from a simple vesicoureteral reflux to a more complex disorder of sexual differentiation. The prognosis and neonatal management of these conditions differ significantly. Evaluation of the fetal perineal anatomy is paramount to making the right diagnosis. The aim of this pictorial essay is to show sonographers how to acquire a perineal midsagittal view in a male fetus, and to demonstrate how this specific view allows assessment of the urethra and penis, to differentiate various genitourinary pathologies.

  相似文献   
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BACKGROUND: The aim of the study was to evaluate the efficacy of adjuvant chemotherapy on survival after resection for gastric cancer. METHODS: Patients were enrolled if they underwent resection of gastric cancer but had lymph node or serosal involvement or both. Surgical resection was either total or partial gastrectomy according to the site of the tumor, and surgeons were allowed to perform either D1 or D2 gastrectomy. The subjects were random assigned in two treatment groups as follows: surgery alone as the control group, or surgery and adjuvant chemotherapy. Nine cycles of 5 days protocol every 4 weeks was proposed to the patients of the chemotherapy group. The protocol included a daily administration of 200 mg/m(2) of folinic acid, 5-fluorouracil (375 mg/m(2) during the first session increasing 25 mg by session until reaching 500 mg/m(2)) and CDDP 15 mg/m(2). Two hundred patients were required. Kaplan-Meier survival curves were compared according to the log-rank and the Mantel-Haenszel methods. RESULTS: In all, 205 patients were enrolled in the study; 104 had surgery alone and 101 had surgery and adjuvant chemotherapy. The patients' characteristics were similar except for the mean age, which was 4 years less in the control group. Because of toxicity, 54% of the patients stopped the protocol before the end of the nine courses, and 46% of the patients received the nine courses including 32% with a decreased dose and 14% with a full dose. The 5-year survival rate was 39% in the control group and 39% in the chemotherapy group. CONCLUSIONS: This protocol of adjuvant chemotherapy failed to improve the 5-year survival after resection for gastric cancer.  相似文献   
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