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21.
22.
Diverticulum of the cecum is a rare, benign, generally asymptomatic lesion that manifests itself only following inflammatory or hemorrhagic complications. A personal series of six cases discusses the difficulty of differential diagnosis at both the preoperative and intraoperative levels. The preferable treatment is simple resection.  相似文献   
23.
The solution structure of the three-heme electron transfer protein cytochrome c7 from Desulfuromonas acetoxidans is reported. The determination of the structure is obtained through NMR spectroscopy on the fully oxidized, paramagnetic form. The richness of structural motifs and the presence of three prosthetic groups in a protein of 68 residues is discussed in comparison with the four-heme cytochromes c3 already characterized through x-ray crystallography. In particular, the orientation of the three hemes present in cytochrome c7 is similar to that of three out of four hemes of cytochromes c3. The reduction potentials of the individual hemes, which have been obtained through the sequence-specific assignment of the heme resonances, are discussed with respect to the properties of the protein matrix. This information is relevant for any attempt to understand the electron transfer pathway.  相似文献   
24.
The acute haemodynamic effects of nifedipine (10 mg sublingually) and isosorbide dinitrate (5 mg sublingually) were compared in 13 patients with heart failure due to acute myocardial infarction. Nifedipine induced a significant reduction in systolic (from 122 ± 5 to 107 ± 3 mm Hg: mean ± SEM; P < 0.002) and diastolic blood pressure (from 85 ± 3 to 75 ± 2 mm Hg; P < 0.01). Heart rate did not change significantly, nor did mean right atrial pressure. The mean pulmonary arterial pressure was lowered from 31 ± 2 to 27 ± 2 mm Hg (P < 0.005). The left ventricular filling pressure decreased from 24 ± 1 to 19 ± 1 mm Hg (P < 0.0001). A significant increase in cardiac index (from 2.33 ± 0.13 to 2.69 ± 0.15 l/min per m2; P < 0.001) and in stroke volume index (from 24 ± 2 to 28 ± 2 ml/beats per m2; P < 0.005) was registered. Systemic vascular resistance fell from 1742 ± 145 to 1308 ± 85 dynes/sec per cm−5 (P < 0.00005). After isosorbide dinitrate was administered a significant reduction in mean right atrial pressure (from 9.5 ± 1.6 to 5.1 ± 1.2 mm Hg; P < 0.0001), in mean pulmonary arterial pressure (from 32 ± 1 to 23 ± 1 mm Hg; P < 0.00001) and in left ventricular filling pressure (from 23 ± 1 to 16 ± 1 mm Hg; P < 0.0001) was seen. No significant change in systolic and diastolic blood pressure, heart rate, cardiac index, stroke volume index and systemic vascular resistance was registered. No side-effects were seen after nifedipine and isosorbide dinitrate were administered.  相似文献   
25.
26.
Serum progesterone sulfates were evaluated in the etiology of gestational diabetes mellitus (GDM). Serum progesterone sulfates were measured using ultra-performance liquid chromatography–tandem mass spectrometry in four patient cohorts: 1) the Hyperglycemia and Adverse Pregnancy Outcomes study; 2) London-based women of mixed ancestry and 3) U.K.-based women of European ancestry with or without GDM; and 4) 11–13 weeks pregnant women with BMI ≤25 or BMI ≥35 kg/m2 with subsequent uncomplicated pregnancies or GDM. Glucose-stimulated insulin secretion (GSIS) was evaluated in response to progesterone sulfates in mouse islets and human islets. Calcium fluorescence was measured in HEK293 cells expressing transient receptor potential cation channel subfamily M member 3 (TRPM3). Computer modeling using Molecular Operating Environment generated three-dimensional structures of TRPM3. Epiallopregnanolone sulfate (PM5S) concentrations were reduced in GDM (P < 0.05), in women with higher fasting plasma glucose (P < 0.010), and in early pregnancy samples from women who subsequently developed GDM with BMI ≥35 kg/m2 (P < 0.05). In islets, 50 µmol/L PM5S increased GSIS by at least twofold (P < 0.001); isosakuranetin (TRPM3 inhibitor) abolished this effect. PM5S increased calcium influx in TRPM3-expressing HEK293 cells. Computer modeling and docking showed identical positioning of PM5S to the natural ligand in TRPM3. PM5S increases GSIS and is reduced in GDM serum. The activation of GSIS by PM5S is mediated by TRPM3 in both mouse and human islets.  相似文献   
27.

Background

The advantages of robot-assisted radical prostatectomy (RARP) over laparoscopic radical prostatectomy (LRP) have rarely been investigated in randomised controlled trials.

Objective

To compare RARP and LRP in terms of the functional, perioperative, and oncologic outcomes. The main end point of the study was changes in continence 3 mo after surgery.

Design, setting, and participants

From January 2010 to January 2011, 120 patients with organ-confined prostate cancer were enrolled and randomly assigned (using a randomisation plan) to one of two groups based on surgical approach: the RARP group and the LRP group.

Intervention

All RARP and LRP interventions were performed with the same technique by the same single surgeon.

Outcome measurements and statistical analysis

The demographic, perioperative, and pathologic results, such as the complications and prostate-specific antigen (PSA) measurements, were recorded and compared. Continence was evaluated at the time of catheter removal and 48 h later, and continence and potency were evaluated after 1, 3, 6, and 12 mo. The student t test, Mann-Whitney test, χ2 test, Pearson χ2 test, and multiple regression analysis were used for statistics.

Results and limitations

The two groups (RARP: n = 60; LRP: n = 60) were comparable in terms of demographic data. No differences were recorded in terms of perioperative and pathologic results, complication rate, or PSA measurements. The continence rate was higher in the RARP group at every time point: Continence after 3 mo was 80% in the RARP group and 61.6% in the LRP group (p = 0.044), and after 1 yr, the continence rate was 95.0% and 83.3%, respectively (p = 0.042). Among preoperative potent patients treated with nerve-sparing techniques, the rate of erection recovery was 80.0% and 54.2%, respectively (p = 0.020). The limitations included the small number of patients.

Conclusions

RARP provided better functional results in terms of the recovery of continence and potency. Further studies are needed to confirm our results.  相似文献   
28.
Platinum microquantities were determined in plasma of patients affected by lung carcinoma during treatment with radiotherapy (RT) and concurrent low-dose continuous infusion ofcis-dichlorodiammineplatinum(II) (CDDP). RT was given at 50 Gy in continuous course; CDDP was continuously infused at 4 mg/m2 daily for 100h/week for 5 weeks, and the infusions were separated by 68h of rest. The percentage of free drug versus total drug in plasma was about 3%. It did not vary with therapy duration and was not significantly different from that found in 5-day continuous infusions at much higher daily doses. Never-theless, maximal values of free Pt in plasma were very low and agreed with the low level of CDDP toxicity encountered on the present administration schedule.  相似文献   
29.
Two new myricetin glycosides, myricetin 7-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside (1) and myricetin 7-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (2), together with the known compounds quercetin 3-O-beta-D-glucopyranoside (3), quercetin 3-O-alpha-L-rhamnopyranoside (4), quercetin 3-O-beta-D-galactopyranoside (5), methyl gallate (6), isovanillin (7), 4-hydroxymethylbenzoate (8), 3,4-dihydroxymethylbenzoate (9), and caffeoyl aldehyde (10) were isolated from the leaves of Tachigalia paniculata. The structures of these compounds were determined by spectroscopic methods. Their antioxidant activity was determined by measuring free-radical scavenging effects using three different assays, namely, the Trolox Equivalent Antioxidant Capacity (TEAC) assay, the coupled oxidation of beta-carotene and linoleic acid (autoxidation assay), and the inhibition of xanthine oxidase activity. Compounds 1, 2, and 6 showed activity in the TEAC test, compounds 5-7 and 10 were moderately active in the autoxidation assay, while compounds 1 and 2 were the most potent of the isolates in the xanthine oxidase test.  相似文献   
30.
rBAT, together with its subunit b(0,+) AT mediates the hetero- and homoexchange of neutral and dibasic amino acids. Since the heteroexchange of dibasic amino acids against neutral amino acids is coupled to net transport of positive charge, this transport is electrogenic. Extracellular addition of histidine could create an inward or an outward current depending on extracellular pH (pH(e)) and cell membrane potential. It has been concluded that histidine may be transported in both its protonated and its neutral form. In this study measurements of cytosolic pH (pH(i)) were performed to test this hypothesis. As a result, addition of protonated histidine at acidic pH(e) to Xenopus oocytes expressing rBAT creates an inward current which is paralleled by cytosolic acidification. Both can be reduced by increase of pH(e). At alkaline pH(e) and simultaneous depolarization of the cell membrane the effect of histidine on pH(i) is virtually abolished. The neutral amino acid leucine does not alter cytosolic pH at neither pH 6.0 nor at pH 8.0. In conclusion, histidine can be transported in either its neutral or its protonated form. Transport of the protonated form is facilitated by extracellular acidification and hyperpolarization of the cell membrane.  相似文献   
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