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71.
Background The aim of this study was to produce a simplified questionnaire for evaluation of the symptoms of gastroesophageal reflux disease (GERD).Methods A total of 124 patients with an endoscopic diagnosis of GERD completed a 50-part questionnaire, requiring only yes or no answers, that covered various symptoms related to the upper gastrointestinal tract, as well as psychosomatic symptoms. The 12 questions to which patients most often answered yes were selected, and were assigned scores (never = 0; occasionally = 1; sometimes = 2; often = 3; and always = 4) to produce a frequency scale for symptoms of GERD (FSSG). Sensitivity, specificity, and accuracy of the FSSG questionnaire were evaluated in another group of patients with GERD and non-GERD. The usefulness of this questionnaire was evaluated in 26 other GERD patients who were treated with proton pump inhibitors for 8 weeks.Results When the cutoff score was set at 8 points, the FSSG showed a sensitivity of 62%, a specificity of 59%, and an accuracy of 60%, whereas a cutoff score of 10 points altered these values to 55%, 69%, and 63%. The score obtained using the questionnaire correlated well with the extent of endoscopic improvement in patients with mild or severe GERD.Conclusions This new questionnaire is useful for the objective evaluation of symptoms in GERD patients.  相似文献   
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Ethylcholine mustard aziridinium ion (AF64A) is a neurotoxic derivative of choline that produces not only long-term presynaptic cholinergic deficits, but also various memory deficits in rats similar to some characteristics observed in Alzheimer's disease patients. This study investigated whether nicotine (NCT) administration attenuated spatial learning deficits induced by intracerebroventricular AF64A treatment. AF64A (6 nmol/6 μl)-or saline (SAL)-treated rats were trained in Morris water maze task. NCT (0.025–0.25 mg/kg) was subcutaneously injected 5 min before the training every day. The results showed that moderate dose (0.10 mg/kg) of NCT attenuated AF64A-induced prolongation of escape latency. Furthermore, NCT dose-dependently recovered the AF64A-induced decrease of time spent in the target quadrant in the probe test. These results suggest that NCT improves AF64A-induced spatial memory deficits, and thus it is a potential therapeutic agent for the treatment of memory deficits in dementia.  相似文献   
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Seventeen children underwent marrowablative high-dose chemotherapy with peripheral blood stem cell autografts and were studied retrospectively to determine the type, frequency, and outcomes associated with infectious complications 3 months postgraft. The patients were kept in isolated rooms with a laminar air flow facility, but no decontamination procedures, such as gut sterilization with nonabsorbable antibiotics, nonmicrobial diet, and skin cleansing, were used. They were under their mothers' daily care to maintain good psychological conditions. After the completion of marrow-ablative chemotherapy and the infusion of stem cells, the absolute granulocyte count exceeded 0.5 × 109/liter with a mean of 17.9 days (range 6–65 days), Fifteen patients developed a total of 16 febrile episodes during the first 4 week period, and the confirmed diagnoses were mucositis (12), enterocolitis (nine), septicemia (four), central venous catheter-associated infection (three), pneumonia (one), perianal abscess (one), and possible invasive fungal infection (one). All episodes were successfully treated with parenteral antibiotic therapy, and no patient died of infectious complications. The observations suggest that high-dose chemotherapy can be performed safely with simple and efficient patient management protocol followed by peripheral blood stem cell autografts.  相似文献   
75.
Rat experimental models using Ar-butyl-Af-(4-hydroxybutyl) nitrosamine(BBN) as an initiating agent have been widely used to studycarcinogenic processes in the urinary bladder. In this study,early neoplastic lesions from 10 male F344 rats treated with0.05% BBN for 16 weeks were analyzed for changes in the H-rasor p53 genes by polymerase chain reaction (PCR)-single strandconformation polymorphism (SSCP) analysis and subsequent DNAsequencing. Lesions were pooled for each of the 10 rats andsix showed point mutations in the p53 gene and one in the H-rasgene. These results would indicate that BBNinduced rat urinarybladder carcinomas are similar to human urinary bladder carcinomaswith respect to alterations in the p53 and H-ras genes and thatp53 gene alterations are relatively early events in rat urinarybladder carcinogenesis induced by BBN treatment  相似文献   
76.
To elucidate whether common genetic events in human urinarybladder carcinogenesis also occur in rodent models, we investigatedthe presence of p53, H- and K-ras mutations in 18 urinary bladdercarcinomas induced by various concentrations of N-butyl-N-(4-hydroxybutyl)nitrosamine(BBN) in male NON/Shi mice. Histopathologically, all were invasive,11 being squamous cell carcinomas (SCCs) and the remaining sevenbeing transitional cell carcinomas (TCCs). Using polymerasechain reaction single-strand conformation polymorphism (PCR-SSCP)analysis followed by DNA sequencing, p53, H- and K-ras mutationswere observed in 14 (78%; exons 5–7), two (11%; one eachon exons 1 and 2) and one (5.6%; exon 1) animals respectively.The frequencies of mutations in p53 exons 5, 6 and 7 were 7(39%), 4 (22%), and 9 (50%) respectively, and no mutation wasfound in exon 8. All mutations involved one base-pair substitutionwith or without amino acid changes and the types of base-pairsubstitution were random. No evident association was observedbetween mutation sites and the histological phenotypes. In conclusion,p53 mutations are frequent in BBN-induced mouse invasive urinarybladder tumors, at similar levels to those observed for humanhigh-grade invasive carcinomas, and this plus their distributionsuggests their possible participation in this model of urinarybladder carcinogenesis.  相似文献   
77.
To identify substances with anti-human immunodeficiency virus (HIV) activity in traditional medicines, water and methanol extracts of crude drugs used in Indian traditional medicine (Ayurveda) were subjected to screening for their inhibitory effects on HIV type 1 protease (PR). The enzyme activity was determined by HPLC and of the 39 crude drugs tested, the extracts of the seeds of Areca catechu, the bark of Eugenia jambolana, the bark of Saraca indica and the stem bark of Terminalia arjuna inhibited the HIV-1 PR activity by more than 70% at a concentration of 0.2 mg/mL. The most potent inhibition was shown by the A. catechu extract, from which some procyanidins were isolated. One of them, arecatannin B1 showed significant HIV-1-PR inhibitory activity.  相似文献   
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OBJECTIVE: The employment of surgical microscopy in the field of neurosurgery has significantly contributed not only to the advancement of surgical technique, but also the operative outcome as well. This technology has allowed surgeons to meet the demands for increasingly difficult levels of surgery, which usually require a long operative time. However, the surgeon and the assistant are restricted in their posture for a long time, leading to excessive muscular and ocular stress. To solve these problems, we have developed and clinically applied a three dimensional video microscope system for surgery, using a two binocular camera method, that allows surgical procedures to be performed over a video monitor. METHOD: Two 3CCD cameras were installed on the assistant's lens attachment and the camera lens attachment of the microscope for neurosurgery, manufactured by Carl Zeiss Co., Ltd. The surgery was performed by viewing the three dimensional picture on the monitor, which was created by processing the images from the cameras by a time-division method. In November 1998, the prototype was completed and, with numerous modifications, its clinical application has become possible. Currently, we have used it in 42 clinical cases. RESULTS: 1) Instead of viewing the surgical field through a conventional surgical microscope, the surgeon and the assistant were able to perform microsurgery by viewing the stereoscopic vision on the video monitor, through polarized glasses. 2) The assistant is provided with a separate video monitor, so that the assistant can freely adjust the angle of vision 90-180 degrees, according to where he stands. 3) The nurses, resident surgeons and students can view the same three dimensional images displayed to the surgeon. This effectively contributes to the educational environment. CONCLUSION: Even during a long surgical procedure, the posture of surgeon and assistant became less restricted since there was no need to look through the eyepiece of the microscope and led to significant decrease in physical fatigue and ocular strain. In the 42 clinical trials, the operation proceeded uneventfully, without any serious complications.  相似文献   
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