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991.
BACKGROUND AND AIM: This prospective study aimed to determine whether Doppler ultrasonography can represent the hepatic venous pressure gradient (HVPG) as an assessment of the severity of portal hypertension and the response to terlipressin, which reduces the portal pressure in liver cirrhosis. METHODS: The HVPG and the Doppler ultrasonographic parameters, such as the portal venous velocity and the splenic venous velocity, the pulsatility and the resistive index of the hepatic, splenic and renal arteries were measured in 138 patients with liver cirrhosis. The changes in the HVPG and the portal venous velocity after administering terlipressin were evaluated in 43 of the 138 patients. The patients who showed a reduction in the HVPG of more than 20% of the baseline were defined as responders to terlipressin. RESULTS: None of the Doppler ultrasonographic parameters correlated with the HVPG. Both the HVPG (28.0 +/- 19.8%) and the portal venous velocity (29.7 +/- 13.2%) showed a significant reduction after terlipressin administration. However, the portal venous velocity decreased significantly, not only in the responders (31.0 +/- 12.0%) but also in the non-responders (25.2 +/- 16.4%). CONCLUSIONS: Doppler ultrasonography does not represent the HVPG, and is therefore not suitable for replacing HVPG as a means of assessing the severity of portal hypertension and the response to drugs which reduce the portal pressure in liver cirrhosis.  相似文献   
992.
Di-n-propylacetic acid (valproic acid) has been reported to lower plasma ACTH concentration after both acute and chronic administration of the drug. To date, there is no report on the efficacy of the drug in inducing regression of ACTH-secreting pituitary adenomas. We report herein our findings in a patient with Nelson's syndrome who was treated with valproic acid for over a year. Despite a lowering of her plasma ACTH concentration during therapy with valproic acid, the patient's tumour showed no evidence of regression while she was taking the drug. In view of these findings, valproic acid therapy for ACTH-secreting pituitary tumours needs to be re-evaluated.  相似文献   
993.
ABSTRACT

The first steps of the HIV care continuum include patients finding access to HIV testing and primary care. Psychosocial providers (“providers”), such as social workers, health educators, and outreach workers comprise a workforce tasked with linking patients to HIV testing and primary care. This study examines longitudinal associations between provider- and organization-level factors and linkage to HIV testing and primary care. The sample included 245 providers in 36 agencies in New York City. We used longitudinal data (baseline and 12- and 24-months follow-ups) and multilevel ordinal logistic regression to examine associations between factors distributed in three theoretical socioecological domains: individual (demographic and HIV training characteristics); relationship (interprofessional collaboration); and agency (size and capacity), and frequency of HIV testing and primary care linkages. Approximately 30% of providers linked 20 or more patients to HIV testing or HIV primary care in the previous six months. Providers’ higher endorsement of interprofessional collaboration at 12 months, formal HIV training, younger age, and Latinx ethnicity had higher odds of making more linkages to HIV testing and HIV primary care at 24 months. Training providers in interprofessional collaboration principles and practice and basic HIV knowledge may improve the frequency of linkages to HIV care continuum services.  相似文献   
994.
Protein modification by ubiquitin is a dynamic and reversible process that is involved in the regulation of a variety of cellular processes. Here, we show that myogenic differentiation of embryonic muscle cells is antagonistically regulated by two deubiquitinating enzymes, UBP45 and UBP69, that are generated by alternative splicing. Both enzymes cleaved off ubiquitin from polyubiquitinated protein conjugates in vivo as well as from linear ubiquitin-protein fusions in vitro. In cultured myoblasts, the level of UBP69 mRNA markedly but transiently increased before membrane fusion, whereas that of UBP45 mRNA increased as the cells fused to form myotubes. Both myoblast fusion and accumulation of myosin heavy chain were dramatically stimulated by the stable expression of UBP69 but strongly attenuated by that of the catalytically inactive form of the protease, suggesting that the mutant enzyme acts dominant negatively on the function of the wild-type protease. In contrast, stable expression of UBP45 completely blocked both of the myogenic processes but that of inactive enzyme did not, indicating that the catalytic activity of the enzyme is essential for its inhibitory effects. These results indicate that differential expression of UBP45 and UBP69 is involved in the regulation of muscle cell differentiation.  相似文献   
995.
Angiopoietin-1 (Ang1) has potential therapeutic applications in inducing angiogenesis, enhancing endothelial cell survival, and preventing vascular leakage. However, production of Ang1 is hindered by aggregation and insolubility resulting from disulfide-linked higher-order structures. Here, by replacing the N-terminal portion of Ang1 with the short coiled-coil domain of cartilage oligomeric matrix protein (COMP), we have generated a soluble, stable, and potent Ang1 variant, COMP-Ang1. This variant is more potent than native Ang1 in phosphorylating the tyrosine kinase with Ig and epidermal growth factor homology domain 2 (Tie2) receptor and Akt in primary cultured endothelial cells, enhancing angiogenesis in vitro and increasing adult angiogenesis in vivo. Thus, COMP-Ang1 is an effective alternative to native Ang1 for therapeutic angiogenesis in vivo.  相似文献   
996.

Purpose

During drug-induced sleep endoscopy (DISE) in patients with obstructive sleep apnea, the increased depth of propofol anesthesia is related to the increased collapsibility of the upper airway with dose-dependent. We examined the effect of remifentanil on propofol concentration during DISE.

Methods

In a prospective randomized trial, 56 adult patients were divided into remifentanil-propofol (n?=?28) and propofol alone (n?=?28) groups. Anesthesia was administered using a target-controlled infusion system. In the remifentanil-propofol group, 0.5 ng/ml remifentanil was administered prior to propofol infusion and its concentration maintained; thereafter, in the propofol alone group, normal saline was injected instead of remifentanil. Propofol was infused at a concentration of 1.5 μg/ml after the target concentration of remifentanil was reached. In both groups, the concentration of propofol was increased by 0.5 μg/ml if the degree of sedation was not sufficient. The sedation level was targeted at observer’s assessment of alertness/sedation (OAA/S) scale 3.

Results

The mean propofol concentration was 2.87?±?0.60 μg/ml in the remifentanil-propofol group, which was lower than that in the propofol alone group (3.38?±?0.72 μg/ml, P?<?0.001). The time until sufficient sedation to perform DISE was shorter in the remifentanil-propofol group (P?<?0.001). Apnea-hypopnea index and the lowest peripheral capillary oxygen saturation (SpO2) during polysomnography showed no statistical difference between groups (P?>?0.05). The lowest SpO2 and VOTE classification during DISE were also not statistically different (P?>?0.05).

Conclusions

Use of remifentanil during DISE reduces the target concentration of propofol required for patient sedation to perform DISE without respiratory depression.
  相似文献   
997.
The clinical course and prognosis of familial hypertrophic cardiomyopathy (HCM) are different according to the type of mutation in the genes for sarcomere proteins. It has been disputed that a mutation, which occurs at a functionally important region in the sarcomere proteins, may increase the penetrance and expressivity of the disease. We searched for a causative mutation in an HCM family, which is characterized by early expression of clinical phenotype, high incidence of sudden death at young ages, and progressive heart failure in adults. Among the 32 family members in 4 generations, 13 were affected; 4 died suddenly before age 16, 2 children have already had full expression of the cardiac hypertrophy, and other adults have either progressive heart failure or poor left ventricular systolic functions. PCR-SSCP (polymerase chain reaction–single strand confirmation polymorphism) analysis of genomic DNAs isolated from peripheral blood leukocytes of the family members identified a Gly716Arg mutation in the cardiac β-myosin heavy chain gene, which was cosegregated with the clinical phenotype. The mutation is localized near a functionally important site of the myosin heavy chain, the 2 active thiols, which contribute to the adenosine triphosphatase activity of myosin S1. This family provides further evidence that the mutation, which occurs at a functionally important site of the myosin heavy chain, is associated with the high penetrance and early expression of HCM.  相似文献   
998.
BackgroundThe clinical course of COVID-19 includes multiple disease phases. Data describing post-hospital discharge outcomes may provide insight into disease course. Studies describing post-hospitalization outcomes of adults following COVID-19 infection are limited to electronic medical record review, which may underestimate the incidence of outcomes.ObjectiveTo determine 30-day post-hospitalization outcomes following COVID-19 infection.DesignRetrospective cohort studySettingQuaternary referral hospital and community hospital in New York City.ParticipantsCOVID-19 infected patients discharged alive from the emergency department (ED) or hospital between March 3 and May 15, 2020.MeasurementOutcomes included return to an ED, re-hospitalization, and mortality within 30 days of hospital discharge.ResultsThirty-day follow-up data were successfully collected on 94.6% of eligible patients. Among 1344 patients, 16.5% returned to an ED, 9.8% were re-hospitalized, and 2.4% died. Among patients who returned to the ED, 50.0% (108/216) went to a different hospital from the hospital of the index presentation, and 61.1% (132/216) of those who returned were re-hospitalized. In Cox models adjusted for variables selected using the lasso method, age (HR 1.01 per year [95% CI 1.00–1.02]), diabetes (1.54 [1.06–2.23]), and the need for inpatient dialysis (3.78 [2.23–6.43]) during the index presentation were independently associated with a higher re-hospitalization rate. Older age (HR 1.08 [1.05–1.11]) and Asian race (2.89 [1.27–6.61]) were significantly associated with mortality.ConclusionsAmong patients discharged alive following their index presentation for COVID-19, risk for returning to a hospital within 30 days of discharge was substantial. These patients merit close post-discharge follow-up to optimize outcomes.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-021-06924-0.KEY WORDS: COVID-19, mortality, re-admission, discharge  相似文献   
999.
We are reporting the first case of acute lymphoblastic leukemia whose individual leukemic cells produced both K and λ light chains, without any heavy chains, as demonstrated by double immunofluorescent staining. This case together with cases of lympho-plasmacytic neoplasia reported in the literature indicates that cells of a single clone are capable of producing more than a single class of light and/or heavy chains.  相似文献   
1000.
ObjectivesThis study evaluated the physiologic characteristics of discordant lesions between instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR) and the prognosis at 5 years.BackgroundFFR or iFR have been standard methods for assessing the functional significance of coronary artery stenosis. However, limited data exist about the physiologic characteristics of discordant lesions and the prognostic implications resulting from these lesions.MethodsA total of 840 vessels from 596 patients were classified according to iFR and FFR; high iFR–high FFR (n = 580), low iFR–high FFR (n = 40), high iFR–low FFR (n = 69), and low iFR–low FFR (n = 128) groups, which were compared with a control group (n = 23). The differences in coronary circulatory indices including the coronary flow reserve (CFR), index of microcirculatory resistance (IMR), and resistance reserve ratio (RRR) (resting distal arterial pressure × mean transit time / hyperemic distal arterial pressure × hyperemic mean transit time), which reflect the vasodilatory capacity of coronary microcirculation, were compared. Patient-oriented composite outcomes (POCO) at 5 years including all-cause death, any myocardial infarction, and any revascularization were compared among patients with deferred lesions.ResultsIn the low iFR–high FFR group, CFR, RRR, and IMR measurements were similar to the low iFR–low FFR group: CFR 2.71 versus 2.43 (p = 0.144), RRR 3.36 versus 3.68 (p = 0.241), and IMR 18.51 versus 17.38 (p = 0.476). In the high iFR–low FFR group, the CFR, RRR, and IMR measurements were similar to the control group: CFR 2.95 versus 3.29 (p = 0.160), RRR 4.28 versus 4.00 (p = 0.414), and IMR 17.44 versus 17.06 (p = 0.818). Among the 4 groups, classified by iFR and FFR, CFR and RRR were all significantly different, except for IMR. However, there were no significant differences in the rates of POCO, regardless of discordance between the iFR and FFR. Only the low iFR–low FFR group had a higher POCO rate compared with the high iFR–high FFR group (adjusted hazard ratio: 2.46; 95% confidence interval: 1.17 to 5.16; p = 0.018).ConclusionsDifferences in coronary circulatory function were found, especially in the vasodilatory capacity between the low iFR–high FFR and high iFR–low FFR groups. FFR–iFR discordance was not related to an increased risk of POCO among patients with deferred lesions at 5 years. (Clinical, Physiological and Prognostic Implication of Microvascular Status; NCT02186093; Physiologic Assessment of Microvascular Function in Heart Transplant Patients; NCT02798731)  相似文献   
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