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排序方式: 共有254条查询结果,搜索用时 24 毫秒
1.
We have utilised a posterior tibial artery flap from the opposite healthy limb for reconstruction of defects of middle and lower third of leg in 6 patients. The flap can be based either distally or proximally as the need be. The results have been quite encouraging.  相似文献   
2.
Serum samples were collected from 24 confirmed cases of typhoid fever, 15 clinically suspected cases and 23 normal healthy controls. The convalescent sera were obtained in 13 of the 24 confirmed typhoid cases. In all, 13 paired sera, 11 acute phase only, 15 clinically suspected and 23 normal serum samples were tested for eliciting bactericidal antibodies to Salmonella typhi. In addition, the Widal test was also performed for comparison. All the 24 acute phase sera as well as 13 convalescent sera were found to be positive by bactericidal antibody test (titre 1:80 or above). Of 15 clinically suspected cases, 5 were positive whereas one of the 23 normal controls sera gave a false positive reaction. In contrast, the Widal test could detect only one of the 24 cases in the acute stage, but all 13 cases showed antibodies at a diagnostic titre level during the convalescent stage. None of the 15 clinically suspected cases or 23 normal controls were positive by the Widal test. The feasibility of using a bactericidal antibody test in sero-diagnosis of typhoid fever is discussed.  相似文献   
3.
This study examined sociodemographic, behavioral and psychosocial factors associated with BMI, weight perceptions and trying to lose weight among African-American smokers (N=600, M=44.2 years, 70% female). Sixty-eight percent of the sample were overweight or obese (sample BMI M=28.0, SD=6.7). Three separate, simultaneous multivariable regression models were used to determine which factors were associated with BMI, weight perceptions and trying to lose weight. Poorer health, female gender and high-school education or higher were significantly associated with higher BMIs (p<0.05). Being female (OR=5.8, 95% CI=3.6-9.3) and having a higher BMI (OR=0.6, 95% CI=0.5-0.6) was associated with perception of overweight and smoking more cigarettes per day (OR=1.0, 95% CI=1.0-1.1), and perceiving oneself as overweight (OR=14.1, 95% CI=8.2-24.2) was associated with trying to lose weight. Participants somewhat underestimated their BMI in their weight perceptions. Those who perceived themselves as overweight were more likely to be trying to lose weight; therefore, increasing participant awareness of actual BMI status may lead to improved weight-control efforts in African-American smokers. Several expected associations with outcomes were not found, suggesting that BMI and weight constructs are not well-understood in this population.  相似文献   
4.
The systemic inflammatory response of the body to invading microorganisms, termed sepsis, leads to profound activation of the complement system. Pathophysiological concepts suggest that complement activation occurs very early in this syndrome. Thus, we discuss whether the determination of concentrations of the complement components C3a, C5a, and C3 in plasma as well as of the C3a/C3 ratio might be helpful to diagnose sepsis early. For this purpose, 33 patients from an intensive care unit were monitored for 10 days. In comparison with healthy donors, C3a levels and the C3a/C3 ratio of intensive-care-unit patients were significantly elevated (P < 0.0001) on admission. In contrast, C3 levels were significantly reduced (P < 0.0001) but increased during the study. C5a levels in the plasma of healthy donors and patients were identical. Twenty-two of 33 patients fulfilled microbiological and clinical criteria of sepsis. Eleven patients had signs of systemic inflammatory response syndrome but no microbiological evidence of sepsis. The groups could be differentiated from each other by their C3a levels or their C3a/C3 ratios during the first 24 h after the clinical onset of sepsis (P < 0.05). Septic patients in shock had higher C3a levels than normotensive septic patients, although the differences were not significant. Nonsurvivors had significantly higher C3a levels on admission than survivors (P = 0.0185). No differences were found between septic patients who developed adult respiratory distress syndrome and those who did not. Thus, determination of C3a concentrations in plasma may prove useful (i) to diagnose sepsis early, (ii) to differentiate between patients with sepsis and those with systemic inflammatory response syndrome, and (iii) to assess prognosis.  相似文献   
5.
New amides from Zanthoxylum lemairie pericarps   总被引:1,自引:0,他引:1  
Two new aromatic amides were isolated from the pericarps of Zanthoxylum lemairie. The structures were elucidated by spectroscopic methods and confirmed by synthesis. A known aromatic amide, zanthosinamide, and four dibenzylbutyrol-actone lignans were isolated.  相似文献   
6.
Tumors of the pineal region are a rare clinical entity, comprising approximately 3%-8% of pediatric tumors. Based on their histopathological features, they are typically classified as pineal parenchymal tumors and germ cell tumors, with the latter being more prevalent. Clinical presentation is heterogeneous, with symptoms arising either due to tumor invasion or compression of adjacent neurovascular structures and increased intracranial pressure. Imaging studies are paramount in evaluating pineal region lesions and establishing an accurate diagnosis, with MRI representing the gold standard. Herein, we present the case of a 16-year-old boy presented with recurrent headaches. A head MRI revealed a pineal gland lesion. Histopathological examination confirmed the diagnosis, and the patient underwent a successful gross total resection (GTR) of the tumor. This case report seeks to draw attention to the elusive clinical presentation and management of this infrequently encountered tumor, as well as emphasize the importance of considering pineal gland tumors in the differential diagnosis of recurrent, chronic headaches in pediatric patients.  相似文献   
7.
Cell cycle dysregulation is one of the defining features of cancer. Cyclin-dependent kinase 4 (CDK4), together with its regulatory subunit cyclin D, governs cell cycle progression through the G1 phase. Cyclin-dependent kinase inhibitors, including p16(INK4A) (encoded by CDKN2A), in turn regulate CDK4. In particular, dysregulation of the p16/CDK4/cyclin D complex has been established in a variety of types of human tumours. Dominant activating mutations affecting codon 24 of the CDK4 gene (replacement of Arg24 by Cys or His) render CDK4 insensitive to p16(INK4) inhibition and are responsible for melanoma susceptibility in some kindreds. However, 'knock-in' mice homozygous for the CDK4(R24C) mutation were noted to develop multiple neoplasia, most commonly including endocrine tumours: pituitary adenomas, insulinomas and Leydig cell testicular tumours. We therefore speculated that sporadic human endocrine tumours might also harbour such mutations. The aim of the current study was to analyze the CDK4 gene for the two characterized activating mutations, R24C and R24H, in sporadic human pituitary adenomas, insulinomas and Leydig cell tumours. We used DNA extracted from 61 pituitary adenomas, and paired tumorous and neighboring normal genomic DNA extracted from 14 insulinoma and 6 Leydig cell tumour samples. Genomic DNA from patients with familial melanoma harbouring the R24C or the R24H mutations served as positive controls. All samples were subjected to PCR, mutation-specific restriction digests and/or sequencing. Both methodologies failed to detect mutations at these two sites in any of the sporadic endocrine tumours including pituitary adenomas, benign or malignant insulinomas or Leydig cell tumours, while the positive controls showed the expected heterozygote patterns. Protein expression of CDK4 was demonstrated by immunohistochemistry and Western blotting in pituitary and pancreatic samples. These data suggest that the changes in the regulatory 'hot-spot' on the CDK4 gene, causing various endocrine tumours in CDK4(R24C/R24C )mice, are not a major factor in sporadic pituitary, insulin beta-cell or Leydig cell tumorigenesis.  相似文献   
8.
Ocular metastases from carcinoid tumors are considered rare. They can be the primary presentation of a carcinoid tumor or develop during the course of the disease. The extent of distant metastases from carcinoid tumors correlates with poor prognosis and survival; early detection of metastasis may change the overall management. Radiopharmaceutical-labeled imaging techniques have been widely applied for the detection and localization of such lesions based on isotope uptake by neuroendocrine tumors. Routine application of these imaging modalities may reveal previously unsuspected lesions and may also be used to help stage the disease and to identify patients who may be treated with radiopharmaceuticals. Of 40 patients with carcinoid tumors reviewed in our department since we started routine scanning, we identified 6 (15%) who demonstrated ocular metastases: 5 with obvious lesions and 1 with presumed metastasis according to the results of nucleotide scanning. All 6 were negative on screening with [(123)I]meta-iodobenzylguanidine, whereas 3 of 4 who were screened with [(111)In]octreotide showed positive uptake. All patients responded well to radiotherapy and chemotherapy and did not require surgical treatment. The orbit and its contents appear to be a common site for carcinoid metastasis, and radiopharmaceutical imaging with labeled octreotide is useful in identifying many of these lesions.  相似文献   
9.

Background

Early in medical education, physicians must develop competencies needed for tobacco dependence treatment.

Objective

To assess the effect of a multi-modal tobacco dependence treatment curriculum on medical students’ counseling skills.

Design

A group-randomized controlled trial (2010–2014) included ten U.S. medical schools that were randomized to receive either multi-modal tobacco treatment education (MME) or traditional tobacco treatment education (TE).

Setting/Participants

Students from the classes of 2012 and 2014 at ten medical schools participated. Students from the class of 2012 (N?=?1345) completed objective structured clinical examinations (OSCEs), and 50 % (N?=?660) were randomly selected for pre-intervention evaluation. A total of 72.9 % of eligible students (N?=?1096) from the class of 2014 completed an OSCE and 69.7 % (N?=?1047) completed pre and post surveys.

Interventions

The MME included a Web-based course, a role-play classroom demonstration, and a clerkship booster session. Clerkship preceptors in MME schools participated in an academic detailing module and were encouraged to be role models for third-year students.

Measurements

The primary outcome was student tobacco treatment skills using the 5As measured by an objective structured clinical examination (OSCE) scored on a 33-item behavior checklist. Secondary outcomes were student self-reported skills for performing 5As and pharmacotherapy counseling.

Results

Although the difference was not statistically significant, MME students completed more tobacco counseling behaviors on the OSCE checklist (mean 8.7 [SE 0.6] vs. mean?8.0 [SE 0.6], p?=?0.52) than TE students. Several of the individual Assist and Arrange items were significantly more likely to have been completed by MME students, including suggesting behavioral strategies (11.8 % vs. 4.5 %, p?<?0.001) and providing information regarding quitline (21.0 % vs. 3.8 %, p?<?0.001). MME students reported higher self-efficacy for Assist, Arrange, and Pharmacotherapy counseling items (ps?≤0.05).

Limitations

Inclusion of only ten schools limits generalizability.

Conclusions

Subsequent interventions should incorporate lessons learned from this first randomized controlled trial of a multi-modal longitudinal tobacco treatment curriculum in multiple U.S. medical schools.NIH Trial Registry Number: NCT01905618
  相似文献   
10.
Despite recommendations suggesting that biological and targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) should be used in combination with methotrexate in the treatment of rheumatoid arthritis (RA), up to one-third of patients with RA are treated with monotherapy. The objective of the systematic literature review reported here was to evaluate the clinical evidence regarding the efficacy of b/tsDMARDs as monotherapy in the treatment of RA. MEDLINE®, Embase®, and the Cochrane Central Trials Register (to April 11, 2017) and the American College of Rheumatology and European League Against Rheumatism conference proceedings (2010–2016) were searched for randomized controlled trials evaluating the efficacy of b/tsDMARDs as monotherapy for RA in adults. Forty-four monotherapy studies of abatacept, adalimumab, baricitinib, certolizumab pegol, etanercept, sarilumab, sirukumab, tocilizumab, and tofacitinib reported in 71 publications were identified. Tocilizumab had the most studies (14), followed by etanercept (10) and adalimumab (9). These b/tsDMARDs were consistently shown to be efficacious treatments, regardless of whether patients were intolerant of or had never used conventional synthetic (cs) DMARDs. However, better treatment outcomes were usually achieved with combination therapy, and this was observed for all b/tsDMARDs assessed by this review. Only a few studies provided a head-to-head comparison between b/tsDMARD treatments or between b/tsDMARD monotherapy and combination therapy, and as many were initial RA treatments they were not generalizable to usual care. In conclusion, evidence from randomized trials suggests that the b/tsDMARDs studied are effective as monotherapy. In general, some patient responses seem better with combination therapy and the durability of monotherapy is less than combination therapy. There is, however, a need for longer-term head-to-head trials to establish positioning of these interventions in the treatment algorithm for RA.Funding: Pfizer.Plain Language Summary: Plain language summary available on the journal website.  相似文献   
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