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141.
Emergence of vancomycin-intermediate Staphylococcus aureus (VISA) and vancomycin-resistant S. aureus (VRSA) strains has led to global concerns about treatments for staphylococcal infections. These strains are currently rare even though there is an upward trend in their reported incidence. Therefore, appropriate screening and epidemiological evaluation of VRSA strains can affect future global health care policies. Isolates of Staphylococcus aureus were obtained from various clinical samples and were then evaluated with agar screening, disk diffusion, and MIC methods to determine resistance to vancomycin and methicillin. After confirmation of the isolated VRSA strain, genetic analysis was performed by evaluating mecA and vanA gene presence, SCCmec, agr, and spa types, and toxin profiles. Multilocus sequence typing (MLST) and plasmid analysis were also performed. The VRSA strain was resistant to oxacillin (MIC of 128 μg/ml) and vancomycin (MIC of 512 μg/ml). Disk diffusion antimicrobial susceptibility tests showed resistance to oxacillin, vancomycin, levofloxacin, ciprofloxacin, trimethoprim-sulfamethoxazole, clindamycin, rifampin, and tetracycline. The isolate was susceptible to minocycline and gentamicin. PCRs were positive for the mecA and vanA genes. Other genetic characteristics include SCCmec type III, agr I, spa type t037, and sequence type (ST) 1283. The plasmid profile shows five plasmids with a size of ∼1.7 kb to >10 kb. The isolated VRSA strain was obtained from a critically ill hospitalized patient. Genetic analysis of this strain suggested that the strain was a methicillin-resistant S. aureus (MRSA) clone endemic in Asia that underwent some genetic changes, such as mutation in the gmk gene and acquisition of the vanA gene.  相似文献   
142.
Patients with advanced non-seminomatous germ cell tumors may achieve a serologic and radiographic complete response (CR) to first-line chemotherapy (defined as a residual mass < 1 cm in size). Recent reports suggest that these patients may be observed with a low rate of relapse but there remain compelling arguments for surgical excision. The arguments for and against post-chemotherapy retroperitoneal lymph node dissection (pcRPLND) are presented. There is clear consensus that patient's with residual masses > 1 cm should undergo post-chemotherapy surgery.  相似文献   
143.
Zoonotoc cutaneous leishmaniasis is endemic in several parts of Iran. Jahrom district is one of the most important endemic foci of leishmaniasis located in Fars province, southern Iran. To identify the vectors of leishmaniasis in this area, a total of 349 sandflies were collected during May to August 2009. They were caught from outdoors in five regions of Jahrom district including villages of Mousavieh, Ghotb-Abad, Heydar-Abad, Fath-Abad and Jahrom County. Eleven species of Phlebotomine (three Phlebotomus spp. and eight Sergentomyia spp.) were detected. To determine the sandflies naturally infected by Leishmania spp., 122 female sandflies were dissected and evaluated microscopically using Giemsa-stained slides. Natural infection of 2 out of 38 (5.26%) P. papatasi and 1 out of 8 (12.5%) P. salehi to Leishmania major was confirmed in the region. Sequencing and nested polymerase chain reaction-based detection of Leishmania were carried out to confirm the microscopic findings. Five (13.16%) P. papatasi and two (25%) P. salehi were positive in nested polymerase chain reaction assay. All positive samples were shown 72-76% similarity with L. major Friedlin. On the basis of our knowledge, this is the first molecular detection of L. major within naturally infected P. salehi in this region in southern Iran.  相似文献   
144.
Background: IL-4 is a cytokine that induces differentiation of naive helper T cells into Th2 cells. Once activated by IL-4, Th2 cells subsequently produce additional IL-4. Objective: To examine the effect of IL-4 on IL-17 production and its effect in Collagen-Induced Arthritis (CIA) mice. Method: In this study, a chicken collagen-II-induced experimental arthritis (CIA) model was used in DBA/1 mice to investigate the relationship between IL-4 and IL-17 as well as other inflammatory factors. On the 38th day after the mice were induced with CIA, the expression of IL-17 and IL-4 as well as IFN-γ and IL-13 in sera of the mice was measured by QRT-PCR and ELISA. Result: The result of QRT-PCR analysis of IL-17 and IL-4 mRNA levels in the spleen showed that IL-17 is increased significantly at the onset of CIA in the spleen (p<0.01). Meanwhile, IL-17 is generally reduced at the peak of CIA but IL-4 is increased significantly at this peak in the spleen when the weight of the animal was taken into consideration (p<0.05). Conclusion: IL-4 can be involved in the production of IL-17 at especially the peak of CIA. These results imply that the inhibition of IL-17 may decrease the expression of IL-1β and IL-6 production which will result in the aggravation of arthritis.  相似文献   
145.
The main problem in the postoperative period is pain relief. Adequate postoperative analgesia not only leads to patient's comfort but also decreases morbidity, nursing care and time of hospitalization. Determination of the effect of intraperitoneal pethidine on postoperative pain in women scheduled for elective tubal ligation was undertaken. In a double blind clinical trial study of 60 women, ASA I, 25-45 years old, were enrolled for elective tubal ligation in Kosar hospital in Qazvin, IRAN. Patients were randomly divided in two equal groups (30 each).One group received pethidine intraperitoneally and the other group received equal amount of placebo in the same region. The intensity of postoperative pain was evaluated by visual analogue scale (VAS) for about 8 hours. Incidence of nausea was also evaluated. Data was transformed to SPSS software. Then data analysis was performed by U-test. There was no significant statistical difference with regard to age, weight, and time of operation between the two groups. The mean score of pain was significantly lower in intraperitoneal pethidine group than placebo group but the incidence of nausea in the intraperitoneal pethidine group was more than in placebo group (P < 0.05). Thus, intraperitoneal pethidine decreases postoperative pain but increases postoperative nausea.  相似文献   
146.
AIM: To investigate eradication rates, patient compliance and tolerability of a 1-wk Azithromycin-based quadruple therapy versus the 2-wk conventional therapy. METHODS: A total of 129 H pylori-positive patients were randomized to either omeprazole 20 mg, bismuth subcitrate 240 mg, azithromycin 250 mg, and metronidazole 500 mg, all twice daily for 1-wk (B-OAzM) or omeprazole 20 mg, bismuth subcitrate 240 mg, amoxicillin 1g, and metronidazole 500 mg all twice daily for 2-wk (B-OAM). H pylori infection was defined at entry by histology and rapid urease test and cure of infection was determined by negative urea breath test. RESULTS: H pylori eradication rates produced by B-OAzM and B-OAM were 74.1% and 70.4% respectively based on an intention to treat analysis, and 78.1% versus 75.7% respectively based on a per-protocol analysis. The incidence of poor compliance was lower, although not significantly so, in patients randomized to B-OAzM than for B-OAM (3.5% versus 4.3%) but intolerability was similar in the two groups ( 35% versus 33.3%). CONCLUSION: 1-wk azithromycin based quadruple regimen achieves an H pylori eradication rate comparable to that of standard 2-wk quadruple therapy, and is associated with comparable patient compliance and complications.  相似文献   
147.
Background:  Chronic alcoholism leads to elevated plasma and brain homocysteine (Hcy) levels, as demonstrated by clinical investigations and animal experiments. It has been posited that elevated levels of Hcy mediate DNA damage, brain atrophy, and excitotoxicity. The current study sought to elucidate the effect of vitamin E on ethanol-induced hyperhomocysteinemia, DNA damage, and atrophy in the developing hippocampus and cerebellum of rats.
Methods:  Pregnant Wistar rats received ethanol with or without vitamin E from gestation day 7 throughout lactation. Weight changes in the brain, hippocampus and cerebellum, DNA damage, and Hcy levels in the plasma, hippocampus, and cerebellum of male offspring were measured at the end of lactation.
Results:  The results revealed that along with a significant decrease in brain, cerebellum, and hippocampus weights in animals that received alcohol, the levels of DNA damage and Hcy significantly increased. Significant amelioration of brain atrophy and DNA damage as well as restoration of the elevated level of Hcy to that of controls were found in vitamin E-treated rats.
Conclusions:  These findings strongly support the idea that ethanol intake by dams during pregnancy and lactation induces Hcy-mediated oxidative stress in the developing hippocampus and cerebellum of offspring rats, and that these effects can be alleviated by vitamin E as an antioxidant.  相似文献   
148.
Asgari S 《Archives of virology》2006,151(9):1689-1699
Summary. Ascoviruses (AVs) infect larvae of various insect pests belonging to the family Noctuidae. The result of AV infection in the hosts is cleavage of infected cells into vesicles, a unique feature of AV infection. Since insect cell lines facilitate the study of virus life cycles, attempts were made to analyze Heliothis virescens AV (HvAV3e) infection in several cell lines and compare cell pathology to larval infection. In this study, replication and cytopathological effects of HvAV3e on four different cell lines were investigated. HvAV3e replication was confirmed in three noctuid cell lines from Spodoptera frugiperda (Sf9) and Helicoverpa zea (BCIRL-Hz-AM1 and FB33). However, the virus did not replicate in the non-noctuid insect cell line from Pieris rapae (Pieridae). Despite replication of the virus in the three permissive cell lines, the cytopathological effects of the virus were significantly different from that of larval infection.  相似文献   
149.
In this paper, we report on the unsteady state modeling of blood flow in an end-to-side anastomosed bypass graft, which has a stenosis upstream from the junction. In coronary artery bypass grafting/surgery (CABG), new arteries are created in order to provide blood to the heart using other blood vessels as conduits to bypass the blocked section in the patient's coronary arteries. The failure of coronary artery bypass procedures has been attributed to both intimal hyperplasia (IH) and atherosclerosis. It is believed that these two phenomena are, in turn, related to the local hemodynamic factors. In this work, a three-dimensional computational fluid dynamics analysis is used to simulate the physiological blood flow through a model of a stenosed coronary bypass graft with the realistic assumption of non-Newtonian flow for human blood. For different flow repartitions and at different times of the cycle, both the recirculating areas and wall shear stress (WSS) are studied. Based on the different distribution of flow rates in the bypass graft and the host artery, the flow features are investigated and the influence of non-Newtonian behavior is discussed in terms of separation points, reattachment points, and the wall shear stresses. Various differences are observed based on the assumption of non-Newtonian behavior of blood, which have not been reported before when a simplified Newtonian approach is utilized.  相似文献   
150.
Does inflammation, as assessed by high sensitivity C-reactive protein (hs-CRP), in patients with end-stage renal disease (ESRD) tightly associate with increased serum levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8- oxo-dG)? Increased oxidative stress and inflammation have both been highlighted among several nontraditional risk factors for cardiovascular disease, which is the main cause of mortality in ESRD patients. In contrast to oxidative stress effects on proteins and lipids, DNA base damage has not been well demonstrated in ESRD. Two groups of hemodialysis patients were studied, one group with persistent inflammation (n = 13, with constant elevation of CRP > 10 mg/L for 6 months) and one group of noninflamed patients (n = 19, with constant CRP < 10 mg/L for 6 months). Serum 8-oxo-dG was significantly elevated in persistent inflammation in comparison to noninflamed patients. At an individual level, a significant correlation was found between serum 8-oxo-dG and hsCRP. Extracellular 8-oxo-dG leads to intracellular oxidative damage on the nucleotide pool, thus providing a sensitive marker for inflammatory response. Serum levels of 8-oxo-dG, in combination with other inflammatory markers, serve as useful diagnostic tools for identification of patients in risk for inflammatory complications.  相似文献   
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