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BACKGROUND Drug toxicity is a common and even serious problem in the gastrointestinal tract that is thought to be caused by a broad spectrum of agents.Although withdrawal of the causative agent would cure the disease knowledge is scarce and mostly derives from case reports and series.AIM To investigate potential triggers of drug-induced colitis(DiC).METHODS We conducted a retrospective,observational case control study.Patients were assigned to DiC or one of two age-and gender-matched control groups(noninflammatory controls and inflammatory colitis of another cause)based on histopathological findings.Histopathology was reassessed in a subset of patients(28 DiC with atherosclerosis,DiC without atherosclerosis and ischaemic colitis each)for validation purposes.Medical history was collected from the electronic database and patient records.Statistical analysis included chi-squared test,t-test,logistic and multivariate regression models.RESULTS Drug-induced colitis was detected in 211 endoscopically sampled biopsy specimens of the colon mucosa(7%of all screened colonoscopic biopsy samples);a total of 633 patients were included equally matched throughout the three groups(291 males,mean age:62.1±16.1 years).In the univariate analysis,DiC was associated with diuretics,dihydropyridines,glycosides,ASS,platelet aggregation inhibitors,nonsteroidal anti-inflammatory drugs(NSAIDs),statins and fibrates,and with atherosclerosis,particularly coronary heart disease,and hyperlipoproteinaemia.Echocardiographic parameters did not show substantial differences.In the multivariate analysis only fibrates[odds ratio(OR)=9.1],NSAIDs(OR=6.7)and atherosclerosis(OR=2.1)proved to be associated with DiC.Both DiC reassessment groups presented milder inflammation than ischaemic colitis.The DiC patients with atherosclerosis exhibited histological features from both DiC without atherosclerosis and ischaemic colitis.CONCLUSION Several drugs indicated for the treatment of cardiovascular and related diseases are associated with DiC.Atherosclerosis and microcirculatory disturbances seem to play an important pathogenetic role.  相似文献   
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The coronavirus disease 2019(COVID-19) pandemic has imposed a radical change in daily life and work routine. In this context, health systems have suffered important and serious repercussions in all fields. Among the changes brought about by the state of global health emergency, adjustments to guidelines, priorities, structures, professional teams, and epidemiological data stand out. In light of this, the oncological field has witnessed several changes in the approach to cancer, whether due to de...  相似文献   
34.
The aim of the present experiment was to assess the effect of the administration of the NSAID flurbiprofen (Froben®) on tissue healing after periodontal surgery. Sites from patients with the same treatment modality (modified Widman flap) but receiving a placebo drug and sites within each patient not exposed to surgery served as controls. Nineteen patients suffering from moderate to severe periodontal disease were recruited and they signed informed consent forms. These patients required periodontal surgery as assessed at the periodontal re-evaluation. The sites chosen for the study were all diagnosed with PPD ≥ 5 mm and were bleeding on probing. During the healing phase 10 patients received 50 mg Froben® 3 times per day for 30 d whereas 9 patients received a placebo drug. Two sites with PPD ≥ 5 mm after initial therapy and bleeding on probing served as surgical sites, whereas 2 similar sites were not exposed to surgery. The study design was set up double-blind. The radiographic examination consisted of 2–4 standardized vertical bitewings obtained at the periodontal re-evaluation (BL) at 1, 3 and 6 months post-surgically for digital subtraction and computer assisted densitometric image analysis (CADIA). The regions of interest analysed were mesial or distal crestal sites. Minimal remodelling activity was observed radiographically after periodontal surgery in both patient groups. There were no statistically significant differences between the four groups of sites regarding the mean changes in density when analysing the pairs of radiographs 0–1, 0–3, 0–6 months. A frequency analysis was performed to list the number of sites with different ranges of density change. No differences in the distributions of the numbers of sites were observed when comparing the 4 site groups (Kolmogorov-Smirnov, p > 0.05). A significant reduction of the probing pocket depth and a significant amount of clinical attachment gain was noted at the surgically treated sites irrespective of whether the patients had used flurbiprofen or placebo. Whereas the pathways leading to bone resorption in periodontally diseased sites have been shown, in other studies, to be influenced by NSAID, the results of the present study could not justify general administration of Froben® for the purpose of reduction of bone resorption after periodontal surgical procedures in patients with adult periodontitis.  相似文献   
35.
BACKGROUND: Recombinant human erythropoietin (rhEPO) increases blood pressure (BP) and the vascular production of endothelin-1 in renal failure rats. This study was designed to investigate the effect of rhEPO on BP and on the ET-1/ET(B)R system in rats with normal renal function. To further characterize the effect of rhEPO on the ET-1/ET(B)R system, we also studied heterozygous (+/-) ET(B)R knockout (KO) mice. METHODS: The animals received either the vehicle or rhEPO (100 U/kg subcutaneously three times per week). ET(B)R(+/-) mice were compared with ET(A)R(+/-) and wild-type (WT) mice. In rats, the ET(B)R mRNA expression was assessed in blood vessels as well as the vascular ET(B)R density using immunohistochemistry. In mice, ET-1 concentration was measured in the thoracic aorta. RESULTS: RhEPO administration increased hematocrit levels in all treated animals. This therapy had no effect on BP in normal rats, but it did increase vascular and renal cortex ET(B)R mRNA expression. Immunohistochemistry confirmed that the ET(B)R density was increased in blood vessel endothelium in these normal rats. In contrast, rhEPO increased BP in ET(B)R(+/-) mice and this pressor effect was associated with higher ET-1 concentrations in the thoracic aorta. CONCLUSIONS: RhEPO exerts a pleotropic effect on the endothelial ET-1/ET(B)R system. The increase in endothelial ET(B)R expression may contribute to maintaining normal BP during rhEPO administration in normal animals. Conversely, conditions with deficient ET(B)R expression, such as in ET(B)R(+/-) mice, may lead to hypertension while receiving the same therapy.  相似文献   
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Several studies have demonstrated that the passive transfer of protective antigen (PA)-neutralizing antibodies can protect animals against Bacillus anthracis infection. The standard protocol for the isolation of PA-neutralizing monoclonal antibodies is based upon a primary selection of the highest PA-binders by ELISA, and usually yields only few candidates antibodies. We demonstrated that by applying a PA-neutralization functionality-based screen as the primary criterion for positive clones, it was possible to isolate more than 100 PA-neutralizing antibodies, some of which exhibited no measurable anti-PA titers in ELISA. Among the large panel of neutralizing antibodies identified, mAb 29 demonstrated the most potent activity, and was therefore chimerized. The variable region genes of the mAb 29 were fused to human constant region genes, to form the chimeric 29 antibody (cAb 29). Guinea pigs were fully protected against infection by 40LD50 B. anthracis spores following two separate administrations with 10 mg/kg of cAb 29: the first administration was given before the challenge, and a second dose was administered on day 4 following exposure. Moreover, animals that survived the challenge and developed endogenous PA-neutralizing antibodies with neutralizing titers above 100 were fully protected against repeat challenges with 40LD50 of B. anthracis spores. The data presented here emphasize the importance of toxin neutralization-based screens for the efficient isolation of protective antibodies that were probably overlooked in the standard screening protocol. The protective activity of the chimeric cAb 29 demonstrated in this study suggest that it may serve as an effective immunotherapeutic agent against anthrax.  相似文献   
38.
Background:  Acid sphingomyelinase (ASM; EC 3.1.4.12) hydrolyses membrane sphingomyelin into the bioactive lipid ceramide and is thus involved in different cellular processes such as differentiation, immunity, or cell death. Activation of ASM has been reported in particular in conjunction with the cellular stress response to several external stimuli, and increased ASM activity was observed in a variety of human diseases. Ethanol-induced activation of ASM has been observed in different cell culture systems, thus raising the question about the effect of alcohol intoxication in human subjects on ASM activity in vivo.
Methods:  We determined ASM activity in peripheral blood mononucleated cells of 27 patients suffering from alcohol dependence. Patients were classified according to their blood alcohol concentration at admission, and ASM activity was determined repeatedly from all patients during alcohol withdrawal.
Results:  Acutely intoxicated patients displayed significantly higher ASM activity than patients in early abstinence (Mann–Whitney U test: Z  = − 2.6, p  = 0.009). ASM activity declined in acutely intoxicated patients to normal values with the transition from the intoxicated state to early abstinence (Wilcoxon test: Z  = −2.7, p  = 0.007). At the end of withdrawal, ASM activity was significantly increased again compared to the early phase of abstinence in both patient groups (Wilcoxon test: Z  = −2.691, p  = 0.007 and Z  = −2.275, p  = 0.023, respectively).
Conclusions:  Alcohol-induced activation of ASM occurs in human subjects and might be responsible for deleterious effects of ethanol intoxication. Chronic alcohol abuse may induce deregulation of sphingomyelin metabolism in general, and this impairment may cause side effects during withdrawal from alcohol.  相似文献   
39.
Abstract:  FHF is characterized by a high percentage of unknown causes leading to acute liver failure and furthermore by an increased morbidity and mortality prior to and post-Ltx. In different transplant centers, the reasons leading to FHF differ significantly as well as outcome. We report our single center experience with 30 pediatric patients receiving a liver transplant for FHF, out of a total of 83 children presenting with FHF. The time to transfer patients to the transplant center after the diagnosis of FHF was long, with a median of 14 days (Ltx group) and 12 days (controls), respectively. In nearly half of the patients (n = 14) in the Ltx group, we were not able to establish an exact diagnosis prior to Ltx: 50% suffered from encephalopathy, and 13 patients were treated in the intensive care unit prior to transplant. Because of the availability of different surgical techniques, all children received a timely transplant [split (n = 18), living donor (n = 9), whole organ (n = 2), and reduced liver (n = 1)]. Patient survival was 93.4%, and graft survival was 83.4% for at least one yr follow-up. Severe complications following Ltx included three cases with aplastic anemia and one child suffering from systemic mitochondrial depletion syndrome. The survival of patients treated medically was 83%. We conclude that a strong focus should be made on early referral to a specialized center and on improvement of diagnostic tools to timely detect the underlying reason for FHF. Results following Ltx for FHF are good.  相似文献   
40.
Aim: To determine if neonates exposed to iodinated contrast media are at risk of hypothyroidism. Methods: A systematic review was conducted by searching electronic databases (e.g. MEDLINE), contacting experts and scanning reference lists. Studies examining the effects of contrast media on neonatal thyroid function were included. Two reviewers independently screened the literature and assessed the risk of bias, while one reviewer abstracted data. Results: Eleven studies were included; nine studies directly examined the risk of hypothyroidism (n = 182 neonates exposed to contrast media). All were highly affected by bias. In the three studies including term infants, one showed a trend towards increased thyroid‐stimulating hormone (TSH) and decreased free thyroxine (FT4) among exposed groups. Six of 72 (8.3%) term infants exposed were treated for hypothyroidism. In studies of premature infants, there was a trend towards increased TSH (n = 3/7 studies), lower total thyroxine (n = 1), decreased triidothyronine and FT4 (n = 3) and hypothyroidism (n = 5). Twenty of 110 (18.2%) premature infants exposed were treated for hypothyroidism. Conclusion: Hospitalized neonates exposed to iodinated contrast media are at risk for abnormal thyroid function and development of hypothyroidism. Premature infants might be at increased risk. Well‐controlled studies are required to replicate our findings because the included studies were highly affected by bias.  相似文献   
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