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11.
This study was intended to determine the number and density of both retinal ganglion cells and the oil droplets of cone photoreceptor cells in brown-eared bulbul (Hysipetes amaurotis). For this study birds were killed with proper dose of anesthetic (pentobarbital, 30 mg/kg), and the eyes were removed from the orbital cavity to isolate the retina. For the ganglion cell study retinal whole-mount specimens were prepared and stained with 0.1% cresyl violet. The different types of oil droplets were counted from color microphotographs of freshly prepared retinal samples. The mean total number of ganglion cells was estimated at approximately 2.5×106; with an average density of 16 523 cells/mm2. Two high-density areas, namely the central area (CA) and the dorso-temporal area (DTA), are located in the central and dorso-temporal retinas, respectively, in bulbuls (24 032 cells/mm2 in the CA; 23 113 cells/mm2 in the DTA). Small ganglion cells persisted in the highest density areas, whereas the largest soma sizes were found in the lowest density areas of the retina. Four types of different colored oil droplets — red, orange, green and clear — were identified with an average density of 29 062/mm2. Among the different colors, the green oil droplets had a significantly higher population (13 083/mm2) than the others across the retina. The central retina had a significantly higher number of all types of oil droplets, at a density of 60 552/mm2. The density and size of the different colored oil droplets were inversely related across the regions of the retina. Taken together, it is concluded that the CA of the retina is an excellent quality area for visual perception due to peak density of ganglion cells and oil droplets. Moreover, each specific oil droplet makes a distinct contribution to visual perception, thereby ensuring that the bird has a retina that best matches its natural environment and feeding behavior.  相似文献   
12.
ObjectivesSeveral studies have recently conducted to investigate the link between anemia and bariatric surgery (BS). The results from these studies, however, were inconsistent. Therefore, a meta-analysis was conducted to determine whether BS for weight loss is a risk factor for anemia.MethodsStudies were identified relevant papers published a cutoff date of May 2022 for meta-analysis by searching four electronic databases (PubMed, EMBASE, Web of Science and Cochrane Library). Pairs of authors conducted title and abstract, full-text assessment, data extraction and risk of bias assessment, and quality of articles. Random-effects models were used to estimate the pooled effect size and evaluated the overall quality of evidence. The sources of heterogeneity were assessed with I2. The Newcastle-Ottawa scale (NOS) was used to assess the methodologic quality of selected studies. The publication bias was assessed using funnel plots and Egger's test statistics.ResultsIn all, eight studies comprising 3150 patients were finally included in the final study analysis. Of these, pooled analysis of eight studies detecting association between anemia and BS for weight loss yield a statistically significant correlation (SMD ?1.12 (?1.46—?0.78, I2 = 93%). Subgroup analyses were performed according to postoperative follow-up time and operation method. Before 24 months postoperatively, no patient had a significant decrease in hemoglobin. More than 24 months after BS, patients show a significant reduction in hemoglobin. In addition, the hemoglobin level was not changed after sleeve gastrectomy (SG) and adjustable gastric banding (AGB) (SMD ?0.19 (?1.04—0.67, I2 = 0% for SG; SMD ?0.30 (?0.82—0.22 for AGB), but the hemoglobin level was significantly reduced after Roux-en-Y gastric bypass (RYGB) (SMD ?1.19 (?1.52—?0.87, I2 = 94.2%).ConclusionThis current meta-analysis found that at 24 months after RYGB, the patient's hemoglobin level was significantly reduced, increasing the risk of anemia. Therefore, attention should be paid to the occurrence of anemia after BS. A large, placebo-controlled, multi-center study is needed to clarify the role of BS for weight loss in this patient anemia.  相似文献   
13.
BackgroundHepatitis C virus (HCV) infected patients have been found to be more susceptible to metabolic syndrome (MetS), but the results remain unclear and lack of a meta-analysis.MethodsDatabases including PubMed, Web of Science, EMBASE and the Cochrane Library were searched to identify all studies concerning HCV and MetS. Funnel plots combined with Begg's tests and Egger's tests were used to analysis the possible publication bias. The odds ratios (ORs) with 95% confidence intervals (CIs) were used to access the effect of HCV infection on the risk of MetS.ResultsEight articles, involving a total of 57387 HCV patients were included. HCV infection was significantly associated with an increased incidence of MetS (OR = 1.73; 95% CI, 1.19–2.52). After adjustment according to the sensitivity analysis, one included article was removed to decrease the publication bias and high heterogeneity, of which the results showed that HCV infection was still associated with an increased incidence of MetS (OR = 1.93; 95% CI, 1.39–2.68).ConclusionsHCV patients tend to have a significant increased risk for MetS, but more large-scale studies are needed to confirm this and explore the exact mechanism.  相似文献   
14.
《Ticks and Tick》2022,13(3):101923
Ticks of the Amblyomma maculatum (Acari: Ixodidae) group are represented by three species: Amblyomma maculatum, Amblyomma tigrinum, and Amblyomma triste. This group is widely distributed throughout the Nearctic and Neotropical regions, from the United States of America (USA) to Argentina. They parasitize several vertebrates, including domestic mammals and humans. Nonetheless, the identification and distribution of the species within the group have been controversial but can be solved with integrative studies on their taxonomy and ecology. In Colombia, a Neotropical country from which up to 58 tick species have been reported, only Amblyomma maculatum Koch, 1844 (sensu stricto - s.s.) - morphotype II – has been molecularly confirmed. Here, specimens of the A. maculatum group from three departments of Colombia were examined by morphological and molecular analyses. The results confirmed the wide distribution of A. maculatum s.s. in Colombia. Furthermore, the presence of A. triste s.s. - morphotype I was confirmed for the first time at the molecular level, which broadens the distribution of this species in the American continent. Considering that both taxa are vectors of pathogens such as Rickettsia parkeri s.s., additional taxonomic, reproductive compatibility and niche distribution studies are needed, as well as the application of new molecular markers due to the controversial taxonomy. This will allow us to explore cryptic diversity within the recently established putative groups.  相似文献   
15.
《Ticks and Tick》2022,13(4):101959
In the south-central United States, several tick-borne diseases (TbDs) occur at or near their highest levels of incidence of anywhere in the U.S. The diversity of Rickettsia species found in Amblyomma americanum continues to be under-characterized in this region and throughout the U.S. and Canada where this tick species is expanding. One reason for this lack of knowledge about Rickettsia diversity is the high prevalence of the endosymbiont Rickettsia amblyommatis that obscures detection of other bacteria in this genus. Focusing on unknown rickettsial agents, we used a recently described R. amblyommatis exclusion assay to screen 1909 A. americanum collected in Oklahoma City, Oklahoma, which resulted in eight ticks that had unique rickettsial sequences. Through the process of characterizing primary and secondary rickettsiae, we identified ticks primarily infected with Rickettsia rhipicephali and a Rickettsia species (2019-CO-FNY) previously linked with a canine rickettsiosis case in Tulsa, Oklahoma. We also identified a Rickettsia agent that was 97% identical with an endosymbiont of Amblyomma tonelliae and which aligned with archaic rickettsial species. Through this study, we further demonstrate the usefulness of this exclusion assay for rapid screening in large cohort A. americanum studies to identify a small number of ticks that contain poorly described and previously undocumented rickettsiae.  相似文献   
16.
《Ticks and Tick》2022,13(5):101974
Rodents are generally recognized to be the reservoir hosts of a great many zoonotic pathogens. In some areas of China, rodent-borne pathogens, as well as the role of rodents in the natural cycle of these pathogens, are still poorly investigated. To increase our knowledge on the distribution and epidemiology of rodent-borne bacterial pathogens, 81 rodent liver samples were collected in three locations of Guizhou province located in Southwest China, and screened for the presence of Ehrlichia, Coxiella, and Bartonella in them. A putative novel Ehrlichia species was identified in 5 Berylmys bowersi samples (100%, 5/5). Its 16S rRNA, gltA, and groEL genes have highest 99.84%, 89.11%, and 98.02% identities to those from known Ehrlichia species, and form distinct clades in the phylogenetic trees. Herein we name it “Candidatus Ehrlichia zunyiensis”. Bartonella was tested positive in 8 A. agrarius (striped field mouse), 2 A. chevrieri (Chevrier's field mouse), 1 R. norvegicus (Norway rat), 1 N. confucianus, and 1 N. lotipes, with a total positive rate of 16.05% (13/81). Sequence analysis indicated high genetic diversity in these Bartonella strains. Unexpectedly, two Coxiella strains were identified from the rodents (1 Niviventer confucianus and 1 Mus pahari). Genetic and phylogenetic analysis indicated that both of them are closely related to the Coxiella endosymbiont of ticks. This result supported previous conjectures that vertebrate hosts such as rodents may play a role in the preservation and transmission of Coxiella endosymbiont of ticks.  相似文献   
17.
《Genetics in medicine》2023,25(3):100351
PurposeNephrolithiasis (NL) affects 1 in 11 individuals worldwide, leading to significant patient morbidity. NL is associated with nephrocalcinosis (NC), a risk factor for chronic kidney disease. Causative genetic variants are detected in 11% to 28% of NL and/or NC, suggesting that additional NL/NC-associated genetic loci await discovery. Therefore, we employed genomic approaches to discover novel genetic forms of NL/NC.MethodsExome sequencing and directed sequencing of the OXGR1 locus were performed in a worldwide NL/NC cohort. Putatively deleterious, rare OXGR1 variants were functionally characterized.ResultsExome sequencing revealed a heterozygous OXGR1 missense variant (c.371T>G, p.L124R) cosegregating with calcium oxalate NL and/or NC disease in an autosomal dominant inheritance pattern within a multigenerational family with 5 affected individuals. OXGR1 encodes 2-oxoglutarate (α-ketoglutarate [AKG]) receptor 1 in the distal nephron. In response to its ligand AKG, OXGR1 stimulates the chloride-bicarbonate exchanger, pendrin, which also regulates transepithelial calcium transport in cortical connecting tubules. Strong amino acid conservation in orthologs and paralogs, severe in silico prediction scores, and extreme rarity in exome population databases suggested that the variant was deleterious. Interrogation of the OXGR1 locus in 1107 additional NL/NC families identified 5 additional deleterious dominant variants in 5 families with calcium oxalate NL/NC. Rare, potentially deleterious OXGR1 variants were enriched in patients with NL/NC compared with Exome Aggregation Consortium controls (χ2 = 7.117, P = .0076). Wild-type OXGR1-expressing Xenopus oocytes exhibited AKG-responsive Ca2+ uptake. Of 5 NL/NC-associated missense variants, 5 revealed impaired AKG-dependent Ca2+ uptake, demonstrating loss of function.ConclusionRare, dominant loss-of-function OXGR1 variants are associated with recurrent calcium oxalate NL/NC disease.  相似文献   
18.
A case in which the intraoperative administration of propofol was strongly associated with an acute episode of diabetes insipidus is presented.  相似文献   
19.
BackgroundStool-based DNA testing for colorectal cancer is becoming a favored alternative to existing DNA screening tests. However, current methods of analysis often become more complicated and costly with increased sensitivity. The high-resolution melting assay (HRMA) is a simple and rapid mutation scanning method with low cost and superb accuracy. In this study, we verified the accuracy of HRMA for screening KRAS/TP53 mutations in stool-isolated DNA from patients with colorectal cancer.Materials and MethodsComparing to direct DNA sequencing, the accuracy of HRMA was verified by detecting KRAS/TP53 mutations in 2 independent stages. In study stage I, both tissue and stool samples from colorectal neoplasm patients were analyzed. In study stage II, stool samples from patients with colorectal neoplasms, and normal controls in clinical screening settings were examined.ResultsIn study stage I, the HRMA identified 14 of 17 target mutations (82.4%) in stools from cancer patients, and 4 of 5 (80.0%) target mutations in stools from advanced adenoma patients. The mutation detection rate in fecal samples (45.0%; 18/40) and referred tissue samples (55.0%; 22/40) was highly consistent (κ = 0.79). The HRMA detected 1% mutant DNA in a background of wild type DNA. In study stage II, the HRMA assay detected 58.8% (20/34) mutations in tumor samples, 41.5% (17/41) in advanced adenomas samples, and 3.33% (2/60) in age-matched normal control samples. The results from HRMA and DNA sequencing revealed 100% sensitivity and specificity in both tissue and stool samples.ConclusionHRMA is a simple, reliable, and sensitive method for detecting DNA mutations in the stool samples from patients with colorectal neoplasms.  相似文献   
20.
Bovine toroviruses (BToVs), belong to the subfamily Toroviridae within the family Coronaviridae, and are pathogens, causing enteric disease in cattle. In Japan, BToVs are distributed throughout the country and cause gastrointestinal infection of calves and cows. In the present study, complete genome sequences of two Japanese BToVs and partial genome sequences of two Japanese BToVs and one porcine torovirus (PToV) from distant regions in Japan were determined and genetic analyses were performed. Pairwise nucleotide comparison and phylogenetic analyses revealed that Japanese BToVs shared high identity with each other and showed high similarities with BToV Breda1 strain in S, M, and HE coding regions. Japanese BToVs showed high similarities with porcine toroviruses in ORF1a, ORF1b, and N coding regions and the 5′ and 3′ untranslated regions, suggestive of a natural recombination event. Recombination analyses mapped the putative recombinant breakpoints to the 3′ ends of the ORF1b and HE regions. These findings suggest that the interspecies recombinant nature of Japanese BToVs resulted in a closer relationship between BToV Breda1 and PToVs.  相似文献   
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