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51.
JI Tang M Back T Shakespeare JJ Lu R Mukherjee C Wynne S Liang 《Journal of Medical Imaging and Radiation Oncology》2005,49(5):390-395
The aims were to determine the median survival and prognostic factors of patients with central nervous system (CNS) metastases managed with whole‐brain radiation therapy (WBRT), and to explore selection criteria in recently published clinical trials using aggressive interventions in CNS metastases. A retrospective audit was performed on patients managed with WBRT for CNS metastases. Potential prognostic factors were recorded and analysed for their association with survival duration. The proportion of patients with these factors was also compared with those of patients managed under three recently reported studies investigating aggressive interventions, such as radiosurgery and chemotherapy for CNS metastases. Seventy‐three patients were treated with WBRT for cerebral metastases over a 12‐month period. The median survival of the population was 3.4 months (95% confidence interval: 2.7–4.1), with 6‐ and 12‐month survival rates of 30 and 18%, respectively. Significant prognostic factors for prolonged median survival were Eastern Cooperative Oncology Group status 0–2 (P = 0.015), Medical Research Council neurological functional status 0–1 (P = 0.006), and Recursive Partitioning Analysis Class 2 versus Class 3 (P = 0.020). On multivariate analysis, younger patient age (P = 0.02) and better performance status (P < 0.01) were associated with improved outcome. When comparing these characteristics with selected published studies, our study cohort demonstrated a higher proportion of patients with poor performance status, a greater number of metastases per patient and a higher incidence of extracranial disease. This reflects the selected nature of patients in these published studies. Central nervous system metastases confer a poor prognosis and, for the majority of patients, aggressive interventions are unlikely to improve survival. The use of potentially toxic and expensive treatments should be reserved for those few in whom these studies have shown a potential benefit. 相似文献
52.
Zoia R. Korobova Elena V. Zueva Natalia A. Arsentieva Oleg K. Batsunov Natalia E. Liubimova Irina V. Khamitova Raisa N. Kuznetsova Artem A. Rubinstein Tikhon V. Savin Oksana V. Stanevich Alexandr N. Kulikov Dmitry E. Pevtsov Areg A. Totolian 《Viruses》2022,14(5)
IgG is the most prominent marker of post-COVID-19 immunity. Not only does this subtype mark the late stages of infection, but it also stays in the body for a timespan of at least 6 months. However, different IgG subclasses have different properties, and their roles in specific anti-COVID-19 responses have yet to be determined. We assessed the concentrations of IgG1, IgG2, IgG3, and IgG4 against different SARS-CoV-2 antigens (N protein, S protein RBD) using a specifically designed method and samples from 348 COVID-19 patients. We noted a statistically significant association between severity of COVID-19 infection and IgG concentrations (both total and subclasses). When assessing anti-N protein and anti-RBD IgG subclasses, we noted the importance of IgG3 as a subclass. Since it is often associated with early antiviral response, we presumed that the IgG3 subclass is the first high-affinity IgG antibody to be produced during COVID-19 infection. 相似文献
53.
Jeremy D. Rubinstein Karen Burns Michael Absalon Carolyn Lutzko Tom Leemhuis Sharat Chandra Patrick J. Hanley Michael D. Keller Stella M. Davies Adam Nelson Michael Grimley 《Pediatric blood & cancer》2020,67(3)
Children with ataxia telangiectasia (AT), a primary immunodeficiency caused by mutations in ATM, which is critical for repairing DNA defects, are at risk for the development of hematologic malignancy, frequently driven by infection with Epstein‐Barr virus (EBV). Conventional chemotherapy is poorly tolerated by patients with AT, with excessive toxicity even when doses are reduced. Here, we report on two patients with AT and EBV‐positive neoplasms who were treated with EBV‐targeted viral‐specific T cells (VST). One patient had a prolonged complete response to VSTs while the other had a partial response. Therapy was well tolerated without infusion toxicity or graft‐versus‐host disease. 相似文献
54.
Herbert M. Rubinstein 《Arthritis \u0026amp; Rheumatology》1975,18(4):357-360
Two brothers with Thiemann' disease are described and the accumulated world literature is briefly reviewed. Thiemann' disease is considered to be a form of idiopathic avascular necrosis of the PIP joints of the hands, with occasional involvement of other joints. The characteristic deformity and x-ray findings are reviewed. Thiemann' disease is a genetic disorder and, in families in which detail is available, is inherited as an autosomal dominant with virtual complete penetrance. 相似文献
55.
Rheumatoid arthritis (RA) and osteoarthritis (OA) are prevalent chronic health conditions. However, despite recent advances in medical therapeutics, their treatment still represents an unmet medical need because of safety and efficacy concerns with currently prescribed drugs. Accordingly, there is an urgent need to develop and test new drugs for RA and OA that selectively target inflamed joints thereby mitigating damage to healthy tissues.Conceivably, biocompatible, biodegradable, disease-modifying antirheumatic nanomedicines (DMARNs) could represent a promising therapeutic approach for RA and OA. To this end, the unique physicochemical properties of drug-loaded nanocarriers coupled with pathophysiological characteristics of inflamed joints amplify bioavailability and bioactivity of DMARNs and promote their selective targeting to inflamed joints. This, in turn, minimizes the amount of drug required to control articular inflammation and circumvents collateral damage to healthy tissues. Thus, nanomedicine could provide selective control both in space and time of the inflammatory process in affected joints.However, bringing safe and efficacious DMARNs for RA and OA to the marketplace is challenging because regulatory agencies have no official definition of nanotechnology, and rules and definitions for nanomedicines are still being developed. Although existing toxicology tests may be adequate for most DMARNs, as new toxicity risks and adverse health effects derived from novel nanomaterials with intended use in humans are identified, additional toxicology tests would be required. Hence, we propose that detailed pre-clinical in vivo safety assessment of promising DMARNs leads for RA and OA, including risks to the general population, must be conducted before clinical trials begin. 相似文献
56.
Stijn JB Van Weyenberg Sietze T Van Turenhout Maarten AJM Jacobs Gerd Bouma Chris JJ Mulder 《Digestive endoscopy》2012,24(4):247-254
Background and Aim: Little is known about the causes of overt obscure gastrointestinal bleeding (OGIB) in patients using anti‐thrombotic therapy. We aimed to describe video capsule endoscopy (VCE) findings and to identify factors associated with positive findings in these patients. Methods: We carried out a retrospective study of 56 patients who underwent VCE for evaluation of previous overt OGIB during anti‐thrombotic therapy. VCE studies were re‐evaluated by a gastroenterologist blinded to clinical details. Clinical data included in the multivariate analysis were sex, age, indication for and type of anti‐thrombotic therapy, hemodynamic instability on admission, type of blood loss, hemoglobin on admission, use of a proton pump inhibitor, NSAID use, time between bleeding episodes and VCE, and whether or not anti‐thrombotic therapy was resumed before the VCE study. Results: A probable cause for gastrointestinal bleeding was identified in 28 (50%) of the 56 studies. Angiodysplasia was found in 19 patients. Twenty‐two studies showed a possible cause in the small bowel. Multivariate logistic regression analysis showed that reinstitution of anti‐thrombotic therapy before VCE was carried out was the only independent predictor of positive VCE findings (OR: 8.61, 95% CI: 1.20–60.42, P = 0.032). Conclusions: Small intestinal angiodysplasia was the most common cause for overt OGIB. Reinstitution of withdrawn anti‐thrombotic drugs before the VCE examination was carried out was associated with positive VCE findings in multivariate analysis. 相似文献
57.
Henry E. Wang Thomas A. Sweeney Robert E. O'Connor Howard Rubinstein 《Prehospital emergency care》2013,17(2):134-141
Objective. To examine the reasons for failed prehospital endotracheal intubation (ETI) and to identify how the airway was subsequently managed in the emergency department (ED). Methods. Data were collected from January to December 1998 for a county-wide paramedic system. Failed prehospital ETIs and perceived reasons for failure were identified. Subsequent ED airway management was reviewed. Results. During the study period there were 13,112 patient contacts resulting in ETI attempts on 592 patients, of whom 536 (90.5%) were successfully intubated. Of the 56 failed field intubations, 49 (87.5%) had ED charts available for review. Endotracheal intubation failure was associated with inadequate relaxation in 24 (49%), difficult anatomy in ten (20%), and obstruction in five (10%). Successful ETI was achieved in the ED in 42 cases (86%). Twenty cases (41%) were facilitated by rapid-sequence intubation (RSI) in the ED. For those with incomplete relaxation in the field, 13 of 24 (54%) were intubated in the ED using RSI. Factors associated with the use of ED RSI include attempted prehospital nasotracheal intubation or attempted prehospital midazolam-facilitated intubation (p < 0.001). The predicted need for RSI in this prehospital system is approximately 3.9%. In eight cases, three or more ETI attempts or the use of rescue airways was required in the ED. The predicted minimum incidence of “truly difficult” intubation in this system is approximately 0.8–1.6%. Conclusions. Paramedic intubation failures result from a variety of factors. Less than half of field intubation failures were remedied in the ED by the use of neuromuscular-blocking agents. A similar number were intubated without the use of RSI. A fraction of failed field ETIs may have resulted from inadequate operator training or experience. A small percentage of field patients were “truly difficult” and required advanced resources in the ED to facilitate airway management. Medical directors should be cognizant of the numerous factors affecting intubation performance when designing and implementing approaches to difficult prehospital airways. 相似文献
58.
59.
Red blood cell (RBC) protein 4.2 deficiency is often associated with a moderate nonimmune hemolytic anemia, splenomegaly, and osmotically fragile RBCs resembling, but not identical to, hereditary spherocytosis (HS). In the Japanese type of protein 4.2 deficiency (protein 4.2Nippon), the anemia is associated with a point mutation in the protein 4.2 cDNA. In this report, we describe a patient with moderate and apparently episodic nonimmune hemolytic anemia with splenomegaly, spherocytosis, osmotically fragile RBCs, reduced whole cell deformability, and abnormally dense cells. Sodium dodecyl sulfate- polyacrylamide gel electrophoresis analysis of the proposita's RBC membrane proteins showed an 88% deficiency of protein 4.2 and a 30% deficiency of glyceraldehyde-3-phosphate dehydrogenase (band 6). Structural and molecular analyses of the proposita's protein 4.2 were normal. In contrast, limited tryptic digestion of the proposita's band 3 showed a homozygous abnormality in the cytoplasmic domain. Analysis of the pedigree disclosed six members who were heterozygotes for the band 3 structural abnormality and one member who was a normal homozygote. Direct sequence analysis of the abnormal band 3 tryptic peptide suggested that the structural abnormality resided at or near residue 40. Sequence analysis of the proposita's band 3 cDNA showed a 232G-->A mutation resulting in a 40glutamic acid-->lysine substitution (band 3Montefiore). Allele-specific oligonucleotide hybridization was used to probe for the mutation in the pedigree, showing that the proposita was homozygous, and the pedigree members who were heterozygous for the band 3 structural abnormality were also heterozygous for the band 3Montefiore mutation. The band 3Montefiore mutation was absent in 26 chromosomes from race-matched controls and in one pedigree member who did not express the band 3 structural abnormality. In coincidence with splenectomy, the proposita's anemia was largely corrected along with the disappearance of most spherocytes and considerable improvements of RBC osmotic fragility, whole cell deformability, and cell density. We conclude that this hereditary hemolytic anemia is associated with the homozygous state for band 3Montefiore (40glutamic acid-->lysine) and a decreased RBC membrane content of protein 4.2. We speculate that band 3 structural abnormalities can result in defective interactions with protein 4.2 and band 6, and in particular, that the region of band 3 containing 40glutamic acid is involved directly or indirectly in interactions with these proteins. 相似文献
60.
Biological warfare is intended to incapacitate a large number of individuals at a single exposure, creating epidemictype disease,
death, and social chaos. The organisms with potential for immediate use as bacteriologic weapons are Bacillus anthracis, Brucella melitensis, Yersinia pestis, and Vibrio cholera, all necessitating antibiotic therapy for a cure. It is reasonable, therefore, to assume that a biological attack, or even
a hoax, would requiure thousands of individuals over a large area to begin antibiotic therapy. Issues such as antibiotic availability,
logistical problems in antibiotic distribution, development of drug resistance, side effects influencing the individual, and
adverse effects on the community due to the impact of mass therapy on the ecology, make biological warfare the most apocalyptic
scenario for the creation of a "postantibiotic era." 相似文献