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1.
The purpose of the study was to attempt to replicate a finding of Persky et al. (1978) that midcycle peak values of testosterone (T) in women predicted differences in frequency of intercourse among married couples. Luteinizing hormone (LH), total testosterone (TT), and free testosterone (FT) values from 10 to 14 daily midcycle blood samples donated by 43 volunteering wives were analyzed against sexual activity patterns reported by the couples over a longer period of time. All couples were contracepting by means other than exogenous hormones or the rhythm method. Each morning through three menstrual cycles husbands and wives recorded independently and on separate forms answers to a series of questions concerning sexual activity in the previous 24 hr. Wives also recorded basal body temperatures (BBT). We designated midcycle values of TT and FT according to several definitions of midcycle. Total testosterone levels at the day of the BBT nadir and the day before the nadir correlated significantly with average intercourse frequency. Correlations with FT were statistically significant regardless of which midcycle measure was used; the day before the BBT nadir gave the highest correlation, 0.618, p = 0.01. Mean testosterone (TT or FT) values were not significantly related. We conclude that female midcycle total testosterone or free testosterone is indexing some unobserved event that affects the frequency of intercourse of couples. We speculate that this event affects the motivation of females, which influences the set point of the compromise frequency characteristic of couples.Research supported in part by NICHD Grant No. 1-R01-HDO7454-01.  相似文献   
2.
B M Zainudin  O Ismail    K Yusoff 《Thorax》1994,49(3):267-269
BACKGROUND--The benefit of adding theophylline to beta 2 agonists in acute asthmatic attacks has been debated frequently. METHODS--In an open randomised study 25 patients with severe acute asthma who presented to the emergency department were treated with either a combined nebulised salbutamol (5 mg/dose) and aminophylline infusion (0.6-0.9 mg/kg/hour), or nebulised salbutamol alone. RESULTS--The responses to treatment as measured by peak expiratory flow (PEF) and the time taken to achieve maximum PEF were similar in both groups. Side effects were observed more commonly in patients receiving the combined treatment. CONCLUSIONS--Nebulised salbutamol is equally efficacious in acute asthma when given alone or in combination with aminophylline.  相似文献   
3.
BACKGROUND: Phage display is an alternative method for constructing and selecting antibodies with desired specificity towards an antigen. OBJECTIVES: To construct a library of single chain variable fragment (ScFv) towards hepatitis B core antigen (HBcAg). To isolate a ScFv phage clone that interacts with HBcAg and to develop a phage-ELISA for detecting the antigen. STUDY DESIGN: Mice were inoculated with HBcAg and RNA was extracted from their spleen cells. The genes encoding heavy (V(H)) and light (V(L)) chains were amplified, linked via PCR and cloned into a phagemid vector. Phage particles displaying ScFv were panned against HBcAg and a selected clone was characterized and employed as a diagnostic reagent for detecting HBcAg in serum samples. RESULTS: A phage clone that interacts with HBcAg was selected from the antibody library. The binding of the phage to HBcAg was inhibited by a cyclic peptide bearing the WSFFSNI sequence. A phage-ELISA was established using the recombinant phage and as low as 10ng of HBcAg can be detected by the assay. CONCLUSION: The ScFv displayed on the surface of filamentous phage is an alternative choice for diagnosis of HBcAg in serum samples.  相似文献   
4.
A method for serological diagnosis of Nipah virus (NiV) is described. DNA encoding truncated G protein of NiV was cloned into the pFastBac HT vector, and the fusion protein to His-tag was expressed in insect cells by recombinant baculovirus. The resulting His-G recombinant fusion protein was purified by affinity chromatography and used as the coating antigen for serological testing by indirect enzyme-linked immunosorbant assay (ELISA). When tested against a panel of swine serum samples, the recombinant G protein-based ELISA successfully discriminated all 40 samples previously determined to be serum neutralizing test (SNT) positive from 11 SNT negatives samples. The data show that the recombinant G protein exhibits the antigenic epitopes and conformation necessary for specific antigen-antibody recognition. The main advantage of the recombinant G protein-based NiV ELISA compared to an ELISA using whole virus antigen is the use of a single antigenic protein instead of inactivated whole virus which is required to be prepared under high risk and cost. This test is suitable for routine diagnosis of NiV and also for epidemiological surveys as it allows highly reliable testing of a large number of sera rapidly.  相似文献   
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BACKGROUND: It is uncertain whether EUS should be performed after a single episode of idiopathic pancreatitis vs. recurrent episodes or if clinical factors can predict positive EUS findings. METHODS: Consecutive patients with a single episode of idiopathic pancreatitis or with recurrent episodes underwent EUS (with analysis of bile for bilirubinate and cholesterol crystals, when possible). The diagnostic yield was compared for patients with a single episode of idiopathic pancreatitis and recurrent episodes (stratified by cholecystectomy status). Predictors of positive EUS findings were sought. EUS was considered "positive" if it identified any possible cause of pancreatitis other than chronic pancreatitis. RESULTS: A total of 370 patients were studied (246 no-cholecystectomy group [134 single episode of idiopathic pancreatitis, 112 recurrent episodes] and 124 post-cholecystectomy group [67 single episode of idiopathic pancreatitis, 57 recurrent episodes]). Overall, EUS yielded a positive finding in 29.2%. For patients in the no-cholecystectomy group, positive EUS findings were not significantly more frequent in those with a single episode of idiopathic pancreatitis vs. those with recurrent episodes (31.3% vs. 32.1%; p = 0.89). In the post-cholecystectomy group, the yield was not significantly different for single episode of idiopathic pancreatitis (29.9%) vs. recurrent episodes (17.5%) ( p = 0.15). Chronic pancreatitis was the only abnormality identified in 30.9% of patients in the no-cholecystectomy group vs. 26.6% of those in the post-cholecystectomy group ( p = 0.24). It was the most common abnormality found in all 4 subgroups (range 16.4%-42.0%) and was approximately twice as frequent in patients with recurrent episodes vs. a single episode of idiopathic pancreatitis (no-cholecystectomy: 42.0% vs. 21.6%, p = 0.0008; post-cholecystectomy: 38.6% vs. 16.4%, p = 0.008). Analysis of bile revealed crystals in 38/80 (47.5%) patients in whom it could be performed. Patients with positive EUS findings tended to be older. CONCLUSIONS: In patients with idiopathic pancreatitis, the yield of EUS is not significantly different after an initial attack or after recurrent attacks. Therefore, it is reasonable to perform EUS after an initial attack of idiopathic acute pancreatitis, especially in older patients.  相似文献   
9.
This study investigated the effectiveness of ionic liquids (ILs) loaded onto the surface of a polymeric adsorbent (βCD-TDI) grafted with modified magnetic nanoparticles (MNPs) via an analysis of water treatment, which resulted in high removal of selected endocrine-disrupting chemicals (parabens). The syntheses of MNPs, MNP-βCD-TDI, and IL-MNP-βCD-TDI were characterised and compared using Fourier transform infrared (FT-IR) spectroscopy, carbon–hydrogen–nitrogen (CHN) analysis, vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), the Brunauer–Emmett–Teller (BET) method, thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The results of SEM and TEM indicated that the pore size distribution exhibited mesoporous characteristics with a small surface area (BET analysis: 42.95 m2 g−1). Furthermore, a preliminary sorption experiment demonstrated the ability of IL-MNP-βCD-TDI to enhance not only the sorption capacity, but also the removal of propyl paraben (PP), butyl paraben (BP), and benzyl paraben (ArP). The adsorption process appeared to be pH-dependent, and hence the optimum pH of 6 was selected for a subsequent batch adsorption study of all the studied parabens with an equilibrium time of 80 min. Next, in an attempt to investigate the interactions that occur between the adsorbent and the adsorbates, adsorption kinetics and isotherm studies were performed. All the studied parabens were found to best fit pseudo-second-order kinetics and the Freundlich isotherm with R2 > 0.98 at room temperature (298 K). The interaction of the host–guest inclusion complex and the π–π interaction between βCD and a selected paraben compound (ArP) were identified by performing 1H nuclear magnetic resonance (NMR), together with ultraviolet-visible (UV-vis) spectroscopic analysis. Finally, the adsorption efficiency of the developed material was practically tested on tap water, drain water, and industrial wastewater, which revealed a significant removal of parabens of up to 60–90% in comparison with a prior analysis.

The main interaction between the synthesized material and the targeted paraben compounds.  相似文献   
10.
Nowadays, chemotherapy is one of the crucial and common therapies in the world. So far, it has been revealed to be highly promising, yet patients suffer from the consequences of severe negative medical dosages. In order to overcome these issues, the enhancement of photothermal chemotherapy with reduced graphene oxide (rGO) as a photothermal agent (PTA) is widely utilised in current medical technologies. This is due to its high near-infrared region (NIR) response, in vitro or in vivo organism biocompatibility, low risk of side effects, and effective positive results. Moreover, rGO not only has the ability to ensure that selective cancer cells have a higher mortality rate but can also improve the growth rate of recovering tissues that are untouched by necrosis and apoptosis. These two pathways are specific diverse modalities of cell death that are distinguished by cell membrane disruption and deoxyribonucleic acid (DNA) disintegration of the membrane via phosphatidylserine exposure in the absence of cell membrane damage. Therefore, this review aimed to demonstrate the recent achievements in the modification of rGO nanoparticles as a PTA as well as present a new approach for performing photochemotherapy in the clinical setting.

rGO of QD-rGO nanocomposite could absorb and convert into heat when harvested under NIR radiation, resulting cell death with reduction of fluorescence.  相似文献   
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