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91.
We performed this study to compare the intrascleral biocompatibility of three materials: non-absorbable hydrogel contact lens polymer, non-absorbable silicone rubber, and absorbable cross-linked sodium hyaluronate. Intrascleral implantation of three different materials was performed in 13 healthy, pigmented rabbits. Implants of methacrylic hydrogel, silicone rubber, and cross-linked sodium hyaluronate were implanted in 10, 8, and 8 eyes, respectively. The animals were euthanized at 7, 30, 180, and 360 days post implantation. The eyes were enucleated and immediately fixed in 10% buffered formalin. Semithin sections were cut and stained with hematoxylin-eosin. Light microscope analysis of the specimens was performed. The least severe inflammatory reaction was observed with cross-linked sodium hyaluronate implants. The number of inflammatory cells in proximity to methacrylic hydrogel and silicone implants at all periods of follow up was similar. The thickest fibrous capsule was observed with silicone implants (average, 28.38 +/- 11.17 microm). This area was thinner with methacrylic hydrogel implants (average, 14.90 +/- 5.57 microm) and was thinnest around sodium hyaluronate implants (average, 7.21 +/- 2.33 microm). For each type of implant, the wall on the conjunctival side of the fibrous capsule was significantly thicker than the wall on the choiroidal side. The space between the implant, scleral flap, and bed was filled soon after surgery with connective tissue rich in vessels. In our study, cross-linked sodium hyaluronate had the highest intrascleral biocompatibility. Although the inflammatory responses of the sclera to methacrylic hydrogel and silicone rubber were similar in nature, a thicker fibrous capsule was generated around silicone implants.  相似文献   
92.
During the period of 2001-2004, 1,514 red foxes from the north and the southeast of Poland were sampled and examined parasitologically for infections with Echinococcus multilocularis. A mean 23.8% were found infected in the whole study area. The highest prevalence (50.0-62.9%) was found in some counties in the northeastern (Warmia-Mazuria) and the southeastern (Carpathian Foothill) part of the country. During the study period, significant differences in the prevalence were found on a regional level. Based on the results obtained to date, the paper presents an overview of the current epidemiological situation of E. multilocularis in the fox population in Poland.  相似文献   
93.
Attenuated live oral typhoid vaccine candidate CVD 909 constitutively expresses Salmonella Typhi capsular polysaccharide antigen (Vi). A randomized, double-blind, heterologous prime-boost clinical study was conducted to determine whether immunity to licensed parenteral Vi vaccine could be enhanced by priming with CVD 909. Priming with CVD 909 elicited higher and persistent, albeit not significant, anti-Vi IgG and IgA following immunization with Vi, than placebo-primed recipients. Vi-specific IgA B memory (B(M)) cells were significantly increased in CVD 909-primed subjects. S. Typhi-specific LPS and flagella IgA B(M) cells were observed in subjects immunized with CVD 909 or with the licensed Vi-negative oral typhoid vaccine Ty21a. CVD 909-induced B(M) cells exhibited a classical B(M) phenotype (i.e., CD3(-)CD19(+)IgD(-)CD27(+)). This is the first demonstration of classical B(M) cells specific for bacterial polysaccharide or protein antigens following typhoid immunization. The persistent IgA B(M) responses demonstrate the capacity of oral typhoid vaccines to prime mucosally relevant immune memory.  相似文献   
94.
Pseudomonas aeruginosa is a multi-drug resistant (MDR) pathogen. It is classified by WHO as one of the most life-threatening pathogens causing nosocomial infections. Some of its clinical isolates and their subpopulations show high persistence to many antibiotics that are recommended by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Thus, there is a need for non-traditional classes of antibiotics to fight the increasing threat of MDR P. aeruginosa. Ionic liquids (IL) are one such promising class of novel antibiotics. We selected four strains of P. aeruginosa and studied the growth inhibition and other effects of 12 different ILs. We used the well-characterized P. aeruginosa PAO1 (ATCC 15692) as model strain and compared it to three other isolates from chronic lung infection (LES B58), skin burn infection (UCBPP-PA14) and keratitis infection (39016), respectively. The ILs consisted of either 4,4-didecylmorpholinium [Dec2Mor]+ or 4-decyl-4-ethylmorpholinium [DecEtMor]+ cations combined with different anions. We found that the ILs with 4,4-didecylmorpholinium [Dec2Mor]+ cations most effectively inhibited bacterial growth as well as reduced strain fitness and virulence factor production. Our results indicate that these ILs could be used to treat P. aeruginosa infections.  相似文献   
95.
Only a few cases of pneumocystis pneumonia (PCP) in Cushing's syndrome have been published in the literature so far. In the majority of these patients, the pneumonia occurred after reduction of the hypercortisolism with medicamentous treatment. We report two cases of PCP during conservative treatment of hypercortisolism. We describe clinical, imaging and laboratory findings in two patients and review published cases of pneumocystits pneumonia in Cushing's syndrome. A 60-year-old woman and 20-year-old man with Cushing's syndrome due to ectopic ACTH syndrome were treated at our department. Both developed pneumocystis pneumonia early after treatment with ketoconazole and ethomidate bromide had been introduced and the levels of cortisol rapidly decreased. PCP prophylaxis in patients with high cortisolemia should be started before treatment of hypercortisolism in current practice. Gradual lowering of plasma cortisol should also reduce the risk of infection by Pneumocystis jiroveci.  相似文献   
96.
Polycyclic aromatic hydrocarbons (PAH) are ubiquitous environmental pollutants, distinguished by genotoxic, hepatotoxic, nephrotoxic and immunotoxic effects. Especially secondary toxicity after bioactivation by microsomal monooxygenases (dependent on cytochromes P450) is characteristic of them. The immunotoxic effect is the result of very global impact on immunological reactivity of an organism and immunosuppression by induction of apoptosis of pre-B lymphocytes represents one of its particular forms. It has been proved that the effect of PAH is caused mostly by the following mechanisms: enzymatic induction by the way of activation of AhR (Aromatic hydrocarbon Receptor); alteration of cellular DNA; development of oxidative stress; increase in the concentration of intercellular calcium and decline of activity of NF-kappaB (Nuclear Factor-kappa B). Most sensitive to these changes are particularly B-lymphocytic precursors and pre-B lymphocytes. Intensity of entire manifestations is also considerably dependent on the presence and intensity of mechanisms of active or passive resistance of cells.  相似文献   
97.
In many published studies, various modifications of the flanker task have been used. Regardless of the flanker task version, the conflict N2 component has been consistently reported and interpreted as evidence for the resolution of conflict introduced by incongruent flankers. However, ERP studies that used the most basic flanker task (i.e., a version with equiprobable congruent and incongruent conditions in which only congruency between the target and flankers is manipulated) have not provided compelling evidence for the conflict N2 component. We report the results of a large‐sample ERP study employing a basic flanker task that allowed us to revisit the mechanism underlying the resolution of conflict introduced by incongruent flankers. In the behavioral data, we observed the classic effect of congruency. In the ERP data, we found three conflict‐sensitive components: (a) an early frontal component, presumably corresponding to P2, (b) P300 for congruent trials, followed by (c) P300 for incongruent trials. We did not find evidence for the conflict N2 component. Based on a review of literature, we propose that the conflict N2 component observed in a basic flanker task might be a frontal aspect of the P300 component. Given previous attempts to attribute the functional role of the ERP components, the absence of the conflict N2 in the basic flanker task suggests that response inhibition may not be crucial for the resolution of conflict induced by incongruent flankers. Instead, the P2 component appears to indicate that selective attention might play an important role in resolving the flanker conflict.  相似文献   
98.
Nematode worms of the genus Trichinella are one of the most widespread zoonotic pathogens. Natural transmission between hosts can only occur through the ingestion of infected meat. To date, two Trichinella species are known to be etiological agents of disease among domestic animals and wildlife in Poland: T. spiralis and T. britovi. In the last decades, since the administration of an oral vaccination against rabies, the red fox population in Poland has increased exponentially. The study area covers the Nowy Targ region: a mountainous area (585–1138 m above the sea) in southern Poland. Of 24 red foxes examined in the study, four were infected with Trichinella isolates: three were identified as T. britovi and one as T. pseudospiralis. The muscle of red foxes infected with T. britovi harboured 2.75, 3.11, 4.4 LPG and with T. pseudospiralis 0.36 LPG. Trichinella larvae were identified at species level by genomic and mitochondrial multiplex PCR, the products of which were sequenced for comparison with other sequences available in GenBank. The sequences obtained from the Polish T. pseudospiralis isolate, deposited in GenBank under the accession numbers JQ809660.1 and JQ809661.1, matched sequences already published in GenBank. Sequence comparison showed a 100% match with the large subunit ribosomal RNA gene of T. pseudospiralis isolate ISS 013, and a 96–95% match with those of T. pseudospiralis isolates ISS 141 and ISS 470. This is the first report of the identification of T. pseudospiralis larvae from red fox in Poland.  相似文献   
99.
Human auditory ossicles, the malleus, the incus, and the stapes, are located in the tympanic cavity in the temporal bone and through forming a chain for the sound transmission from the tympanic membrane to the cochlea, they play an important role in the hearing process. Despite their clinical, phylogenetic, and evolutionary significance, the morphometry of the human ear bones has not been examined systematically. The ear ossicles are the smallest bones of the human skeleton, attaining their final size and morphology already at birth. Initially, they have been found to exhibit minimal morphometric variation, but further studies brought the opposite results. The aim of this study was to examine the morphometric variation of human auditory ossicles recovered from medieval and postmedieval subadult skeletons from Poland, Central Europe. The analysis involved in a total of 166 ear bones. Their measurements were performed on microscopic images using CorelDraw x4, according to a protocol of Quam and Rak with modification of Flohr et al. and Wadhwa et al. Our study showed a significant metric variation in the measurements taken at areas of the greatest morphological variability of the ossicles. We found that greater linear dimensions were associated with lower values of angular measurements. These results reveal the inherent variation found in these supposed functionally constrained structures. Representation of even greater number of populations, time periods, and developmental stages are needed. Further study will expand our understanding of the global scope of variation found in ear ossicular morphology and its functional implications for paleoanthropology.  相似文献   
100.
Diabetes mellitus (DM) is a heterogeneous group of disorders whose common trait is chronic hyperglycemia. Gestational diabetes mellitus (GDM) is one of the subtypes of DM that manifests during pregnancy. It is believed that 2%–5% of pregnancies worldwide are complicated with GDM, with the prevalence having significantly increased over the last decade. While the pathogenesis of the disease remains largely unknown, GDM is believed to be a result of interactions between genetic, epigenetic, and environmental factors. Linkage and association studies, including those that are genome-wide, have allowed us to identify complex genetic and epigenetic mechanisms that lead to the development of GDM. Multiple common variants in candidate genes such as potassium inwardly rectifying channel subfamily J, member 11 (KCNJ11), glucokinase (GCK), or hepatocyte nuclear factor 1α (HNF1A) have been found to increase the disease risk. In this review, we provide a detailed overview of the current knowledge concerning the influence of genetics and epigenetics on the development of GDM.  相似文献   
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