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1.
N‐(prop‐1‐yne‐3‐yl)‐4‐(piperidine‐1‐yl)‐1,8‐naphthalimide (PNPr), i.e., the monomer with a terminal ethynyl group and 1,8‐naphthalimide fluorophore, has been successfully copolymerized with a series of monoethynylarenes into well‐soluble high‐molecular‐weight (Mw up to 210 000) linear polyacetylene‐type copolymers containing from 14 to 51 mol% units derived from PNPr. The copolymerization of PNPr with bifunctional 4,4′‐diethynylbiphenyl provides polyacetylene‐type micro/mesoporous fluorescent network containing 8 mol% PNPr units and exhibiting the Brunauer–Emmett–Teller surface of ≈1000 m2 g?1. The copolymerizations (catalyzed with acetylacetonato(norborna‐2,5‐diene)rhodium complex, [Rh(nbd)acac]) proceed smoothly despite the fact that the homopolymerization of PNPr fails. The fluorescence of PNPr (emission at ≈ 510 nm) has been retained after the incorporation of PNPr into the copolymers. The fluorescence of the copolymers can be induced by a direct excitation of PNPr units or via an energy transfer mechanism. In the latter case, the comonomeric units with aromatic hydrocarbon fluorophores (e.g., of the biphenyl‐type) emitting at 380–400 nm (after irradiation with 300 nm UV radiation) serve as energy donors for fluorescent PNPr acceptors. The difference between the wavelengths of the primary absorbed radiation and the finally emitted radiation is 210 nm.

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2.

Background

A retrospective study was undertaken to define the efficacy of both mini gastric bypass or one anastomosis gastric bypass (MGB/OAGB) and sleeve gastrectomy (SG) in type 2 diabetes mellitus (T2DM) remission in morbidly obese patients (pts).

Methods

Eight European centers were involved in this survey. T2DM was preoperatively diagnosed in 313/3252 pts (9.62 %). In 175/313 patients, 55.9 % underwent MGB/OAGB, while in 138/313 patients, 44.1 % received SG between January 2006 and December 2014.

Results

Two hundred six out of 313 (63.7 %) pts reached 1 year of follow-up. The mean body mass index (BMI) for MGB/OAGB pts was 33.1?±?6.6, and the mean BMI for SG pts was 35.9?±?5.9 (p?<?0.001). Eighty-two out of 96 (85.4 %) MGB/OAGB pts vs. 67/110 (60.9 %) SG pts are in remission (p?<?0.001). No correlation was found in the % change vs. baseline values for hemoglobin A1c (HbA1c) and fasting plasma glucose (FPG) in relation to BMI reduction, for both MGB/OAGB or SG (ΔFPG 0.7 and ΔHbA1c 0.4 for MGB/OAGB; ΔFPG 0.7 and ΔHbA1c 0.1 for SG). At multivariate analysis, high baseline HbA1c [odds ratio (OR)?=?0.623, 95 % confidence interval (CI) 0.419–0.925, p?=?0.01], preoperative consumption of insulin or oral antidiabetic agents (OR?=?0.256, 95 % CI 0.137–0.478, p?=?<0.001), and T2DM duration >10 years (OR?=?0.752, 95 % CI 0.512–0.976, p?=?0.01) were negative predictors whereas MGB/OAGB resulted as a positive predictor (OR?=?3.888, 95 % CI 1.654–9.143, p?=?0.002) of diabetes remission.

Conclusions

A significant BMI decrease and T2DM remission unrelated from weight loss were recorded for both procedures if compared to baseline values. At univariate and multivariate analyses, MGB/OAGB seems to outperform significantly SG. Four independent variables able to influence T2DM remission at 12 months have been identified.
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3.
A modified one-step process was used to prepare tetracalcium phosphate/monetite/calcium sulfate hemihydrate powder cement mixtures (CAS). The procedure allowed the formation of monetite and calcium sulfate hemihydrate (CSH) in the form of nanoparticles. It was hypothesized that the presence of nanoCSH in small amounts enhances the in vitro bioactivity of CAS cement in relation to osteogenic gene markers in mesenchymal stem cells (MSCs). The CAS powder mixtures with 15 and 5 wt.% CSH were prepared by milling powder tetracalcium phosphate in an ethanolic solution of both orthophosphoric and sulfuric acids. The CAS cements had short setting times (around 5 min). The fast setting of the cement samples after the addition of the liquid component (water solution of NaH2PO4) was due to the partial formation of calcium sulfate dihydrate and hydroxyapatite before soaking in SBF with a small change in the original phase composition in cement powder samples after milling. Nanocrystalline hydroxyapatite biocement was produced by soaking of cement samples after setting in simulated body fluid (SBF). The fast release of calcium ions from CAS5 cement, as well as a small rise in the pH of SBF during soaking, were demonstrated. After soaking in SBF for 7 days, the final product of the cement transformation was nanocrystalline hydroxyapatite. The compressive strength of the cement samples (up to 30 MPa) after soaking in simulated body fluid (SBF) was comparable to that of bone. Real time polymerase chain reaction (RT-PCR) analysis revealed statistically significant higher gene expressions of alkaline phosphatase (ALP), osteonectin (ON) and osteopontin (OP) in cells cultured for 14 days in CAS5 extract compared to CSH-free cement. The addition of a small amount of nanoCSH (5 wt.%) to the tetracalcium phosphate (TTCP)/monetite cement mixture significantly promoted the over expression of osteogenic markers in MSCs. The prepared CAS powder mixture with its enhanced bioactivity can be used for bone defect treatment and has good potential for bone healing.  相似文献   
4.
BACKGROUND: To present the long-term anatomical and functional results and the dynamics of proliferative vitreoretinopathy (PVR) after precise segmental scleral buckling without drainage, known as extraocular minimal surgery. PATIENTS AND METHODS: In a prospective study 172 consecutive rhegmatogenous PVR detachments were included which were operated on between January 1994 and February 1996 at the Department of Ophthalmology, Higher Medical Institute, Plovdiv, Bulgaria, with cryopexy and segmental scleral buckling without drainage. The follow-up ranged between 54 and 79 months (xmacr; 5S years). In 43 eyes was a PVR stage A, in 50 stage B, in 60 stage CP, and in 19 a PVR stage CA. All detachments were studied precisely for retinal breaks pre- and intraoperatively and the breaks tamponaded by a precise buckle. RESULTS: 1. Anatomical results: Complete retinal reattachment in 145 eyes (84 %) after 1 operation and in 148 eyes (86 %) after reoperation, residual tractional detachment with reattached macula in 12 eyes (7 %) and detachment due to progression of PVR in 12 eyes (7 %). 2. Functional results: Postoperative visual acuity ranged between 0.3 and 1.0 in 111 eyes after xmacr; 5S years. 3. Dynamics of PVR: In 113 detachments (65,7 %) PVR regressed completely and in 12 (7 %) it progressed; among these were 8 eyes with preoperative PVR-CA and 4 eyes with PVR-CP. CONCLUSIONS: Treatment of PVR detachments with nondrainage and minimal buckling provides good anatomical results with macular reattachment in 93 %, resulting in good long-term visual function. Results were best in detachments with PVR stage A, B and CP.  相似文献   
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The effect of nanosilica on the microstructure setting process of tetracalcium phosphate/nanomonetite calcium phosphate cement mixture (CPC) with the addition of 5 wt% of magnesium pyrophosphate (assigned as CT5MP) and osteogenic differentiation of mesenchymal stem cells cultured in cement extracts were studied. A more compact microstructure was observed in CT5MP cement with 0.5 wt% addition of nanosilica (CT5MP1Si) due to the synergistic effect of Mg2P2O7 particles, which strengthened the cement matrix and nanosilica, which supported gradual growth and recrystallization of HAP particles to form compact agglomerates. The addition of 0.5 wt% of nanosilica to CT5MP cement caused an increase in CS from 18 to 24 MPa while the setting time increased almost twofold. It was verified that adding nanosilica to CPC cement, even in a low amount (0.5 and 1 wt% of nanosilica), positively affected the injectability of cement pastes and differentiation of cells with upregulation of osteogenic markers in cells cultured in cement extracts. Results revealed appropriate properties of these types of cement for filling bone defects.  相似文献   
9.
Squamous cell carcinoma of the cornea without involvement of the conjunctiva and limbus is a very rare condition. We report on a 68-year-old female patient. Lamellar keratectomy was performed combined with brachytherapy with strontium-90 for a total dose of 120 Gy (single daily dose: 10 Gy). Two months after treatment, a regression of neovascularization was noted. During 3.5 years of follow-up, no rubeosis of the iris, secondary glaucoma, or evidence of tumor recurrence was seen. There were no regional or distant metastases.  相似文献   
10.
BACKGROUND: Balkan endemic nephropathy (BEN) is a non-inflammatory, chronic, slow progressing kidney disease, frequently associated with urinary tract tumors. BEN displays familial clustering without an apparent Mendelian inheritance pattern. It has been suggested that environmental toxicants damage urothelial cells in genetically susceptible individuals, which could be the cause of BEN. The metabolism of some substrates that are mediated by glutathione S-transferases (GST), which are polymorphic enzymes, results in nephrotoxic products. To evaluate whether GST genetic heterogeneity could be involved in BEN, we launched a case-control study concerning the association of the most common polymorphic GST variants with BEN. METHODS: DNA was extracted from venous blood samples from 54 unrelated BEN patients and 104 controls inhabiting the same endemic region. GSTM1 and GSTT1 null deletions were identified simultaneously by a triplex polymerase chain reaction (PCR) procedure, and GSTP1 polymorphism was analyzed by PCR-restriction fragment length polymorphism (PCR-RFLP) using Alw261. RESULTS: Carriers of at least one GSTM1 wild type allele (wt-allele) were more prevalent among BEN patients compared to controls (chi2=7.92, p=0.005). The GSTT1 and GSTP1 genotype distributions did not demonstrate statistically significant differences between the groups. The carriers of at least one GSTM1 wt-allele among BEN patients were more prevalent in comparison with controls when the GSTM1 genotypes were combined in pairs with all GSTT1 (chi2=9.52, p=0.023) and GSTP1 (chi2=11.92, p=0.036) genotypes. The combined genotype distributions of the three GST genes studied among BEN patients and controls showed that the frequency of carriers of at least one GSTM1 wt-allele among BEN patients was higher or at least equal to the corresponding frequency among controls in all triple combinations. However, this difference did not reach statistical significance (chi2=14.06, p=0.170). CONCLUSIONS: GSTM1 wt-allele associates with BEN. The significantly lower prevalence of the GSTM1 deletion homozygotes among BEN patients suggests that individuals bearing the GSTM1 null genotype could be better protected.  相似文献   
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