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141.
142.
A 29-year-old male was admitted because of thrombocytopenia. A diagnosis of acute lymphoblastic leukaemia was made on the basis of a 61.6% infiltration of leukemic cells in his bone marrow. Standard G-binding chromosome analysis of bone marrow cells revealed a normal karyotype. He received combination chemotherapy, and achieved hematological complete remission. However, chromosomal analysis of bone marrow cells after 2 courses of consolidation therapy showed the Philadelphia (Ph) chromosome in two cells out of 20 analysed. We retrospectively examined the sample of bone marrow cells before chemotherapy; It showed minor BCR/ABL positivity with FISH and RT-PCR methods. The Ph chromosome disappeared after consolidation chemotherapy and allogeneic bone marrow transplantation, but the Ph chromosome reappeared at relapse. We postulated that there were two clones, both a Ph-positive clone and Ph-negative clone. At the initial diagnosis, Ph chromosome was not detected because the G-banding method analyzed only metaphase cells, which contained few Ph-positive clones. In order to offer effective therapy with molecular targeting agents, in this poor prognostic disease, it is necessary to detect Ph chromosome before the first chemotherapy and BCR/ABL detection with FISH or RT-PCR methods appears more useful than G-banding chromosome analysis.  相似文献   
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We report a case of hepatocellular carcinoma (HCC) occurring in a patient with Crohn's disease (CD) without chronic hepatitis or liver cirrhosis, and review the clinicopathological features of HCC in CD patients. A 37-year-old Japanese man with an 8-year history of CD and a medication history of azathioprine underwent resection of a liver tumor. The histopathology of the liver tumor was pseudoglandular type HCC. In the nonneoplastic liver, focal hepatocyte glycogenosis (FHG) was observed, however, there was no evidence of liver cirrhosis or primary sclerosing cholangitis. Only nine cases of HCC in CD patients have been reported previously in the English-language literature. Eight of 10 cases (including the present case) had received azathioprine treatment, and four of these cases also showed FHG, which is considered a preneoplastic liver lesion, within the non-neoplastic liver. Although the precise mechanism of the development of HCC in CD patients is controversial, these results suggest that azathioprine therapy and FHG in the non-neoplastic liver contribute to the development of HCC. These findings also indicate that it is important to survey CD patients treated with prolonged azathioprine therapy for potential liver tumors.  相似文献   
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146.
Background This study was carried out to investigate whether eye-hand coordination skill on a virtual reality laparoscopic surgical simulator (the LAP Mentor) was able to differentiate among subjects with different laparoscopic experience and thus confirm its construct validity. Methods A total of 31 surgeons, who were all right-handed, were divided into the following two groups according to their experience as an operator in laparoscopic surgery: experienced surgeons (more than 50 laparoscopic procedures) and novice surgeons (fewer than 10 laparoscopic procedures). The subjects were tested using the eye-hand coordination task of the LAP Mentor, and performance was compared between the two groups. Assessment of the laparoscopic skills was based on parameters measured by the simulator. Results The experienced surgeons completed the task significantly faster than the novice surgeons. The experienced surgeons also achieved a lower number of movements (NOM), better economy of movement (EOM) and faster average speed of the left instrument than the novice surgeons, whereas there were no significant differences between the two groups for the NOM, EOM and average speed of the right instrument. Conclusions Eye-hand coordination skill of the nondominant hand, but not the dominant hand, measured using the LAP Mentor was able to differentiate between subjects with different laparoscopic experience. This study also provides evidence of construct validity for eye-hand coordination skill on the LAP Mentor.  相似文献   
147.
Background The first step toward increasing the level of patient safety in endoscopic surgery is for all endoscopic surgeons to acquire fundamental skills, including psychomotor skills, in the preoperation stage of training. The current study aimed to evaluate the effectiveness of virtual reality (VR) simulator training and box training for training the fundamental skills of endoscopic surgery. Methods For this study, 35 medical students at Kyushu University were divided into three groups: simulator (SIM) group (n = 20), box trainer (BOX) group (n = 20), and control group (n = 15). None of the students had any experience assisting with endoscopic surgery or any previous training for endoscopic surgery. The students in the SIM group underwent training using a VR simulator, the Procedicus MIST, 2 h per day for 2 days. The students in the BOX group underwent training using a box trainer 2 h per day for 2 days. The students in the control group watched an educational video for 30 min. The endoscopic surgical skills of all the students were evaluated before and after training with a task of suturing and knot tying using a box trainer. Results Although no significant differences were found between the three groups in the total time taken to complete the evaluation task before training, there were significant improvements in the SIM and BOX groups after training compared with the control group. Box training increased errors during the task, but simulator training did not. Conclusion The findings showed that box training and VR training have different outcomes. The authors expect that the best curriculum for their training center would involve a combination that uses the merits of both methods.  相似文献   
148.

Object

We have developed a robotic minimally invasive surgical system within a tele-surgery capability and conducted several times of tele-surgery experiments including Japan–Thailand and Japan–Korea tele-surgery experiments by using conventional network infrastructures. In these experiments, laparoscopic cholecystectomies have been successfully performed on pigs. On the other hand, repetitive task evaluation studies are also crucial for further studies on tele-surgery applications. Nowadays, task evaluations of tele-robotic system within network time-delay have been studied in past years by many researchers. These experiments have been mostly focused on simplified tasks such as a peg-in-hole task. However, most of surgical procedures in minimally invasive surgery are based on medical specific skills such as anatomical knowledge and past experiences of surgeons. From these perspectives, a trial experiment within two tasks including surgery oriented manipulations was conducted to study the impact of network time-delay and force feedback on tele-surgery.

Materials and methods

The experiment was conducted by using the minimally invasive surgical system. As the experimental setup, a research and development Internet, JGN2 (Japan Gigabit Network 2) was used as a network infrastructure, and two tasks were performed by 15 subjects including 5 medical doctors. The trial conditions were given by changing time-delay (on the both tasks) and force feedback (on the first task). The first task was configured to test a simple surgical procedure, which is commonly performed in a laparoscopy as translational motions of surgical tools. The subjects were instructed to touch four columns located on points of a square. The second task was configured to test integrated surgical procedures. The subjects were instructed to perform a part of suturing procedures by using the robotic bending forceps.

Results

In the first task, the completion time was increased approximately 50% by time-delay. By using force feedback, the applied force was decreased. However, the effectiveness of force feedback was not strongly shown in MD group. On the other hand, the effectiveness of the force feedback was strongly shown in the applied force on the tip of surgical tool in both MD and non-MD groups. In the second task, the adverse impact of time-delay was not strongly shown in MD group. From the analysis of the motion records found that a skill of experienced surgeons on “occlusion problem” could be related in the results. These results indicate that skilful operators on surgical procedures can overcome the adverse impact of time-delay by introducing their skills depending on required surgical tasks. However, the drawback of time-delay still remains concerning on safety issues. The effectiveness of the force feedback was strongly shown in the first task in terms of the applied force on the surrounding environment.

Conclusions

Force feedback is an essential technology for further applications of tele-surgery. In addition, the force feedback technology can be partially used for compensating the drawback of time-delay.  相似文献   
149.
BACKGROUND: Wheat protein hydrolysates have been traditionally used as food additives and are now being used in cooking worldwide. There have been a few studies on the relationship between the molecular mass distribution and the immunoglobulin E (IgE) reactivity of the wheat protein hydrolysates. METHOD: We analyzed the peptide profile of commercial wheat protein hydrolysate samples from enzymatic or acid hydrolysis of wheat protein using size exclusion chromatography. We further investigated the IgE reactivity of the wheat protein hydrolysates using the inhibition ELISA method and sera of 5 patients sensitive to wheat. RESULTS: The wheat protein enzymatic hydrolysate samples showed high concentrations of peptides with molecular masses greater than 1,050 Da, whereas in contrast, the wheat protein acid hydrolysates showed extremely low concentrations of peptides with molecular masses greater than 1,050 Da. Tested wheat protein acid hydrolysates hardly inhibited the patient IgE binding ability to wheat proteins in the five patient sera. On the contrary, some tested wheat protein enzymatic hydrolysate samples inhibited the IgE binding ability to wheat proteins. CONCLUSION: These results suggested that the uptake of wheat protein enzymatic hydrolysates might still have the possibility of causing food allergic reactions in patients allergic to wheat and the processed foods containing them.  相似文献   
150.
Objectives Serum creatinine (Scr) is not a reliable marker of renal function in critically ill patients because of an enhancement of protein catabolism, which makes it difficult to adjust the dosage of renally eliminated drugs such as antibiotics. This study aimed to investigate whether serum cystatin C (Scys‐C) could be used as a reliable marker of renal function. Methods We investigated whether Scys‐C was a reliable marker of renal function in 56 critically ill patients. Subsequently, the usefulness of Scys‐C to determine the initial loading and the maintenance dose of vancomycin was examined in 18 patients. Crea‐ tinine clearance (Ccr) was assessed from Scr and creatinine in urine collected over 24 h (24‐h Ccr). Key findings There was a good correlation between 24‐h Ccr and 1/Scys‐C (r2 = 0.616), whereas less marked correlation was observed between 24‐h Ccr and 1/Scr (r2 = 0.221). On the other hand, vancomycin concentration was predicted from population pharmacokinetic parameters based on a two‐compartment linear model. There were significant correlations between real trough concentrations of vancomycin and the values predicted from Scys‐C using various equations (r2 = 0.416–0.488), while less pronounced relationships were observed between real concentrations and the values predicted from Scr (r2 = 0.134–0.187). Conclusions These findings suggest that Scys‐C is a reliable marker reflecting renal function in critically ill patients and is applicable to determine the initial loading dose as well as the maintenance dose of vancomycin.  相似文献   
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