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141.
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We have developed a rapid and sensitive assay for the detection of Salmonella serovars in veterinary clinical specimens. This method utilizes a short cultivation period followed by PCR. For detection of the amplified product, an enzyme-linked immunosorbent assay (ELISA)-based oligonucleotide ligation assay (OLA) was used. In this study, the PCR-OLA technique was compared with conventional culture and membrane hybridization for the detection of Salmonella bacteria. In evaluating the PCR-OLA with Salmonella serovars and non-Salmonella strains of bacteria, A490 readings for 51 Salmonella strains, representing 28 serovars, were significantly higher (P < 0.05) than those for 25 non-Salmonella bacteria. With serial 10-fold dilutions of Salmonella CFU or with known concentrations of purified chromosomal DNA from Salmonella typhimurium ATCC 29946, the PCR-OLA was able to detect > or = 20 CFU per assay or > or = 80 fg of chromosomal DNA (corresponding to 160 molecules of DNA). Of 102 suspect clinical specimens screened, 15 were positive for Salmonella bacteria by both culture and the PCR-OLA procedure (100% sensitivity), and 3 samples were positive only by PCR-OLA (96.6% specificity), indicating a positive predictive value of 83.3% and a negative predictive value of 100%. In all experiments, the PCR-OLA was as sensitive as membrane hybridization. These results indicate that a limited enrichment cultivation and PCR-OLA could be used as a presumptive screening test for the detection of Salmonella serovars from any sample that currently requires extensive cultivation and that this assay would be adaptable to automation.  相似文献   
143.
Testicular microlithiasis   总被引:1,自引:0,他引:1  
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144.
Understanding the process of behavior change interventions is critical to achieving campaign effectiveness and successful program replication. The present article presents a community education monitoring system (CEMS) using data from the Stanford Five-City Project (FCP), the Minnesota Heart Health Program (MHHP) and the Pawtucket Heart Health Program (PHHP). CEMS records the number and type of intervention activities, outcome objectives, targets of change (individual, organizational or environmental), channel(s) of dissemination and proportion of programs funded by the community. These data illustrate (1) the application of theory for each project, (2) data-based program administration, (3) feedback for revising programs and (4) type of reach or 'dose' information obtained from intervention monitoring. Process evaluations such as CEMS provide critical links between field realities and evaluation outcomes. This type of evaluation develops standards for measuring program reach and allows comparisons with other programs. CEMS also illustrates how programs enact theory. Validation studies are critical to the continued successful use of CEMS. The first step, however, is to develop a uniform way of describing complex multichannel behavior change programs. CEMS in a refined form should prove invaluable to health promotion program planners whether in research or service settings.  相似文献   
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the cumulative dose effect of ketamine hydrochloride (KH) on transcranial magnetic-induced motor evoked potentials (MEPs) was examined in monkeys. Electromyographic (EMG) responses were recorded from the contralateral abductor pollicis brevis (APB) and abductor hallucis (AH) muscles. MEP brain stimulation threshold, latency, and amplitude values were studied. After obtaining baseline recordings, increments of KH (5 mg/kg every 15-20 min) were given i.v. (50 mg/kg total dose). MEPs were repeatedly recorded following KH injections. No loss of potentials was encountered in any animal. However, KH induced significant MEP latency delay in doses >/=35-40 mg/kg and amplitude depression in doses >/=15-20 mg/kg (p < 0.01). Under various KH doses, the amplitude depression ranged from 13.6 to 45.5% for APB and 57.3 to 82% for AH compared to the control values. The MEP latency prolongation ranged from 3.5 to 18% for APB and 4.2 to 13.1% for AH. The stimulation threshold rise ranged from 6.7 to 14.7% for APB and 7 to 17.9% for AH. Statistical correlation was closest between cumulative KH doses and MEP latency prolongation. We conclude that, in the primate model, reliable MEP recording is feasible under deep KH anesthesia. However, awareness of drug-induced response alterations is essential during interpretation of intraoperative MEP changes. Further investigation is warranted regarding the specific dose effect in humans and safety of magnetic stimulation.  相似文献   
147.
During 1988-89, studies were conducted to evaluate the immunization system in Conakry, Guinea. The first, a health facility survey, found that health staff screened the vaccination status of only 30% of children who presented for curative care. A sterile syringe and needle were used for less than half of the injections. In the second survey, key informant interviews with vaccinators and health centre chiefs showed that there were minimal lines of communication between health workers and the community, but that health workers did not perceive this to be a problem. Focus group discussions in the community revealed a high level of general knowledge about vaccine-preventable diseases. However, mothers did not know how many vaccinations their children should receive or by what age they should be completed. They complained of long waiting times in health centres, the high costs of vaccination, poor rapport with health workers, and the occurrence of abscesses after vaccination. The final study, a "knowledge, attitudes, and practice" community survey, showed that missed immunization opportunities and inappropriately timed vaccinations reduced potential vaccine coverage by almost 30% among children with vaccination cards. Higher socioeconomic status, delivery in hospital, and whether mothers perceived the vaccinations to be affordable affected whether the child began the immunization series. Once a child had entered the immunization system, completion of the series was determined by the mother's education level, employment status, and experience with vaccination services.  相似文献   
148.
Coronavirus disease 2019 (COVID-19) remains a major public health concern, and vaccine unavailability, hesitancy, or failure underscore the need for discovery of efficacious antiviral drug therapies. Numerous approved drugs target protein kinases associated with viral life cycle and symptoms of infection. Repurposing of kinase inhibitors is appealing as they have been vetted for safety and are more accessible for COVID-19 treatment. However, an understanding of drug mechanism is needed to improve our understanding of the factors involved in pathogenesis. We tested the in vitro activity of three kinase inhibitors against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including inhibitors of AXL kinase, a host cell factor that contributes to successful SARS-CoV-2 infection. Using multiple cell-based assays and approaches, gilteritinib, nintedanib, and imatinib were thoroughly evaluated for activity against SARS-CoV-2 variants. Each drug exhibited antiviral activity, but with stark differences in potency, suggesting differences in host dependency for kinase targets. Importantly, for gilteritinib, the amount of compound needed to achieve 90% infection inhibition, at least in part involving blockade of spike protein-mediated viral entry and at concentrations not inducing phospholipidosis (PLD), approached a clinically achievable concentration. Knockout of AXL, a target of gilteritinib and nintedanib, impaired SARS-CoV-2 variant infectivity, supporting a role for AXL in SARS-CoV-2 infection and supporting further investigation of drug-mediated AXL inhibition as a COVID-19 treatment. This study supports further evaluation of AXL-targeting kinase inhibitors as potential antiviral agents and treatments for COVID-19. Additional mechanistic studies are needed to determine underlying differences in virus response.  相似文献   
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INTRODUCTION: Patients transported by helicopter often require advanced airway management. The purpose of this study was to determine whether or not the in-flight environment of air medical transport in a BO-105 helicopter impairs the ability of flight nurses to perform oral endotracheal intubation. SETTING: The study was conducted in an MBB BO-105 helicopter. METHODS: Flight nurses performed three manikin intubations in each of the two study environments: on an emergency department stretcher and in-flight in the BO-105 helicopter. RESULTS: The mean time required for in-flight intubation (25.9 +/- 10.9 seconds) was significantly longer than the corresponding time (13.2 +/- 2.8 seconds) required for intubation in the control setting (ANOVA, F = 38.7, p < .001). All intubations performed in the control setting were placed correctly in the trachea; there were two (6.7%) esophageal intubations in the in-flight setting. The difference in appropriate endotracheal intubation between the two settings was not significant (chi 2 = 0.3; p > 0.05). CONCLUSION: Oral endotracheal intubation in the in-flight setting of the BO-105 helicopter takes approximately twice as long as intubation in a ground setting. The results support pre-flight intubation of patients who appear likely to require urgent intubation during air medical transport in the BO-105 helicopter.  相似文献   
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