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71.
72.
Herein, we disclose the first example of an efficient, silver oxide nanoparticle-catalyzed, direct regioselective synthesis of 3-ylidenephthalides 11–16 and isocoumarins 17–20via sonogashira type coupling followed by substrate-controlled 5-exo-dig or 6-endo-dig cyclization reaction, respectively. This one pot coupling involves reaction of substituted 2-halobenzoic acid with meta/para-substituted and ortho-substituted terminal alkynes, which proceeded in a regioselective manner resulting in the formation of 3-ylidenephthalides or isocoumarins, respectively, in excellent yields (up to 95%) with complete Z-selectivity. This protocol features relatively broad substrate scope, mild conditions, operational simplicity, and is favourable with aromatic/alicyclic terminal alkynes. The competition experiments and gram-scale synthesis further highlight the importance and versatility of the methodology. The proposed mechanistic pathways illustrate that the regioselectivity is substantially being controlled by the substituent(s) present on the acetylenic phenyl ring.

We report the first example of an efficient, Ag2O nanoparticle-catalyzed, direct regioselective synthesis of 3-ylidenephthalides and isocoumarins via Sonogashira type coupling followed by substrate-controlled 5-exo-dig or 6-endo-dig cyclization reaction, respectively.  相似文献   
73.
Metabolic Brain Disease - Mild cognitive impairment (MCI) is transition phase between cognitive decline and dementia. The current study aims to investigate altered metabolic pattern in plasma of...  相似文献   
74.
Frequent occurrence of hypogonadotropic hypogonadism in type 2 diabetes   总被引:6,自引:0,他引:6  
Type 2 diabetes is associated with lower total testosterone (T) levels in cross-sectional studies. However, it is not known whether the defect is primary or secondary. We investigated the prevalence of hypogonadism in type 2 diabetes by measuring serum total T, free T (FT), SHBG, LH, FSH, and prolactin (PRL) in 103 type 2 diabetes patients. FT was measured by equilibrium dialysis. FT was also calculated by using T and SHBG (cFT). Hypogonadism was defined as low FT or cFT. The mean age was 54.7 +/- 1.1 yr, mean body mass index (BMI) was 33.4 +/- 0.8 kg/m(2), and mean HbA1c was 8.4 +/- 0.2%. The mean T was 12.19 +/- 0.50 nmol/liter (351.7 +/- 14.4 ng/dl), SHBG was 27.89 +/- 1.65 nmol/liter, and FT was 0.250 +/- 0.014 nmol/liter. Thirty-three percent of patients were hypogonadal. LH and FSH levels were significantly lower in the hypogonadal group compared with patients with normal FT levels (3.15 +/- 0.26 vs. 3.91 +/- 0.24 mIU/ml for LH and 4.25 +/- 0.45 vs. 5.53 +/- 0.40 mIU/ml for FSH; P < 0.05). There was a significant inverse correlation of BMI with FT (r = -0.382; P < 0.01) and T (r = -0.327; P < 0.01). SHBG correlated inversely with BMI (r = -0.267; P < 0.05) but positively with age (r = 0.538; P < 0.001) and T (r = 0.574; P < 0.001). FT correlated strongly with cFT (r = 0.919; P < 0.001) but not with SHBG. LH levels correlated positively with FT (r = 0.287; P < 0.05). We conclude that hypogonadotropic hypogonadism occurs commonly in type 2 diabetes.  相似文献   
75.
BACKGROUND: Public participation in many preventive health programs is suboptimal. While various interventions to increase participation have been studied, the impact of a celebrity spokesperson on cancer screening has not been rigorously examined. The objective of this study was to assess the impact of Katie Couric's March 2000 Today Show colorectal cancer awareness campaign on colonoscopy rates. METHODS: A population-based observational study was conducted using 2 different data sources: (1) The Clinical Outcomes Research Initiative (CORI) database-a voluntary consortium of 400 endoscopists who performed 95 000 colonoscopies from July 1998 to December 2000; and (2) 44 000 adult members of a managed care organization. Using change point analyses and linear regression models, we compared colonoscopy utilization rates before and after Ms Couric's March 2000 television series. RESULTS: The number of colonoscopies performed per CORI physician per month after Ms Couric's campaign increased significantly (15.0 per month before campaign; 18.1 after campaign; P<.001). After adjusting for temporal trends, a significantly higher postcampaign colonoscopy rate was sustained for 9 months. Analysis also demonstrated a trend toward an increase in the percentage of colonoscopies performed on women (43.4% before campaign; 47.4% after campaign; P =.054). Colonoscopy rates also increased significantly in the managed care organization after Ms Couric's campaign (1.3 per 1000 members per month before; 1.8 after; P<.001). CONCLUSIONS: Katie Couric's televised colon cancer awareness campaign was temporally associated with an increase in colonoscopy use in 2 different data sets. These findings suggest that a celebrity spokesperson can have a substantial impact on public participation in preventive care programs.  相似文献   
76.

Aim

To find out the prevalence of obesity and glucose intolerance among nurses working in tertiary care hospital.

Methods

Study was conducted in 496 apparently healthy females comprising two groups. Group B had 290 nurses and control group A had 206 age matched female subjects of general population. Detailed performa was filled which included anthropometry, systemic examination and other details. Fasting plasma glucose was done followed by oral glucose tolerance test (OGTT). Subjects with body mass index ≥23?kg/m2 were categorized as ‘overweight’ and ≥25?kg/m2 as ‘obese’ as per criteria for Asian Indians. Women with waist circumference of ≥80?cm were categorized as ‘centrally obese’.

Results

Mean age of subjects in groups A and B was 40.45?±?8.64?years and 40.50?±?6.96?years respectively. Significantly higher number of nurses (80%) were overweight or obese compared to controls (59.71%,P?=?<?.001). Similarly, central obesity was significantly higher in nurses (82.07%) compared to controls (67.96%,P?=?<.001). The prevalence of glucose intolerance (prediabetes and newly detected diabetes) was significantly higher in controls compared to nurses (45.63% vs 29.66%, P?<?.001).

Conclusion

Every four out of five nurses working in tertiary care hospital have overweight/obesity and central obesity. Despite this they have lower rates of glucose intolerance.  相似文献   
77.
Peritoneal Tuberculosis: Laparoscopic Patterns and Its Diagnostic Accuracy   总被引:7,自引:0,他引:7  
We report laparoscopic findings in 38 proven cases of peritoneal tuberculosis. The laparoscopic appearances can be classified into three types: thickened peritoneum with miliary yellowish white tubercles with or without adhesions (n = 25), only thickened peritoneum with or without adhesions (n = 8), and fibroadhesive pattern (n = 5). Biopsies were avoided from fibroadhesive lesions due to risk of complications. Visual diagnosis was accurate in 95% of patients. In comparison, in 27 (82%) of 33 patients, the examination enabled a histologic diagnosis to he made on the basis of typical granulomas. The combined use of guinea pig inoculation and culture isolated Mycobacterium tuberculosis in six (37.5%) of 16 patients. Mycobacteria were scarcely (3%) seen on histological sections. We conclude that, although target biopsy is an effective method of obtaining an early diagnosis of peritoneal tuberculosis, chemotherapy may be started on the basis of visual laparoscopic appearances alone.  相似文献   
78.
Interplay between complement factors, regulatory proteins, anaphylatoxins and cytokines could be involved in tendon healing and scar formation. The expression and regulation of complement factors by cytokines or anaphylatoxins are completely unclear in tendon.Hence, the gene expression of the anaphylatoxin receptors C3aR, C5aR and cytoprotective complement regulatory proteins (CRPs) was analysed in human tendon, cultured primary tenocytes and to directly compare the general expression level, additionally in human leukocytes. Time-dependent regulation of complement by cytokines and the anaphylatoxin C3a was assessed in cultured tenocytes.Gene expression of the anaphylatoxin receptors C3aR, C5aR and the CRPs CD46, CD55 and CD59 was detected in tendon, cultured tenocytes and leukocytes, whereas CD35 could only be found in tendon and leukocytes. Compared with cultured tenocytes, complement expression was higher in tendon and compared with leukocytes C3aR, C5aR, CD35 and CD55, but not CD46 and CD59 gene expression levels were lower in tendon. C3aR mRNA was up-regulated by both TNFα and C3a in cultured tenocytes in a time-dependent manner whereby C5aR gene expression was only induced by C3a. IL-6 or C3a impaired the CRP gene expression. C3a stimulation lead to an up-regulation of TNFα and IL-1β mRNA in tenocytes. Degenerated tendons revealed an increased C5aR and a reduced CD55 expression.The expression profile of the investigated complement components in tendon and cultured tenocytes clearly differed from that of leukocytes. Tenocytes respond to the complement split fragment C3a with CRP suppression and enhanced pro-inflammatory cytokine gene expression suggesting their sensitivity to complement activation.  相似文献   
79.
Food allergy is an immune provocation induced by certain food in susceptible individuals. Most of the food allergic manifestations are evident in the individual having impaired oral tolerance. In spite of worldwide prevalence, there is no permanent cure of food allergy. Food allergic reactions are complex immunological events that comprises of several immune molecules like IgE, IL-4, IL-13 and T-cells, therefore, researchers are trying to pick the correct molecule to find out pivotal therapeutic solutions. Being a key regulatory molecule in suppressing T-cells functional activities, cytotoxic T-cell lymphocyte antigen-4 (CTLA-4) or cluster of differentiation-152 (CD-152) has contributed a novel and revolutionary dimension toward therapeutic research of several diseases. This review focuses on different immunological and mechanistic perspectives of CTLA-4 in correlation with food allergy.  相似文献   
80.
Overactive B cells, abnormally activated T cells and inappropriate handling of cellular debris by the innate immune system are central in the pathogenesis of systemic lupus erythematosus (SLE). Genetic studies in SLE patients have unraveled allelic variations in genes encoding key molecules that control inter- and intra-cellular signaling and play a role in the abnormal handling of apoptotic material. Despite recent breakthroughs though, it is still unclear how exactly genes and environment interact to produce the characteristic immune dysregulation in SLE.  相似文献   
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