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51.
A recombinant Escherichia coli expressing the Neurospora crassa metallothionein gene (NCP) has previously been shown to remove low levels of Cd and other metals from solution. For further development as a biosorbent, the encapsulation of the NCP is investigated by various matrices. The NCP was encapsulated in alginate, chitosan-alginate or kappa-carrageenan, and its physical properties characterized. Results indicated that encapsulation in alginate resulted in fragile beads, whereas encapsulation in kappa-carrageenan or chitosan-alginate provided more physical and chemical integrity to the beads. Maximal heavy metal removal by cells encapsulated in carrageenan occurred within 3 h, while a gradual increase in removal was observed up to 24 h for cells encapsulated in chitosan-alginate. Metal removal by cells encapsulated in alginate beads was lower than those encapsulated in carrageenan or chitosan-alginate.  相似文献   
52.
BACKGROUND: We have consistently achieved about 90% eradication of H. pylori with liquid bismuth, metronidazole and oxytetracycline. AIM: To test eradication and adverse events of ranitidine bismuth citrate (RBC) when given with metronidazole and either oxytetracycline or spiramycin. METHODS: One hundred and eighty-three patients were randomized to one of four 10-day regimens: RBC400OM: RBC 400 mg b.d., oxytetracycline 500 mg q.d.s.; RBC400SM: RBC 400 mg b.d., spiramycin 1 g q.d.s.; RBC200OM: RBC 200 mg q.d.s., oxytetracycline 500 mg q.d.s.; RBC200SM: RBC 200 mg q.d.s., spiramycin 1 g q.d.s. Additionally, all patients received metronidazole 400 mg q.d.s. A 14C-urea breath test was performed at 8 weeks. RESULTS: Intention-to-treat eradication rates were 94%, 91%, 94% and 89% with RBC400OM, RBC400SM, RBC200OM and RBC200SM, respectively (P = 0.81). Eradication was significantly higher in ulcer patients (97%) than in those with diagnoses other than ulcer (86%) (P = 0.009). There was a strong tendency to better eradication among those who had never smoked (100%) compared with ex-smokers (93%) and smokers (89%) (P = 0.06). Fifty-three per cent experienced at least one moderate or severe adverse event, and women had more adverse events than men (P = 0.0002). CONCLUSIONS: All four regimens had comparable efficacy and adverse events. Eradication was significantly better in ulcer patients but there was a trend to better eradication in those who smoked less, used less alcohol and exercised more. Adverse events were frequent, perhaps because of the large dose of metronidazole used, but few patients stopped treatment.  相似文献   
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When fed 10 ppm of one of the following sterols: cholesterol (cholest-5-en-3β-ol), wingsterol (21-isopentylcholesterol), desmosterol [cholesta-5,24(25)-dien-3β-ol], 24-methylenecholesterol [ergosta-5,24(28)-dien-3β-ol], or fucosterol [stigmasta-5,24(28)-dien-3β-ol], the pathogenic fungus Phytophthora cactorum, which is naturally unable to epoxidize squalene, accumulated each of the test compounds to similar levels. Fucosterol, the only sterol metabolized, was reduced to yield 24-ethylcholesterol. All the sterols tested induced the formation of sex structures. Fertilization and subsequent maturation of oospores capable of germination occurred only with the naturally occurring sterols. Wingsterol treatments resulted in aborted oospores. None of the sterols tested was inhibitory to growth, measured as changes in the 21-day mycelial dry weight. The results are consistent with the view that the accumulated sterol functions to regulate the life cycle of P. cactorum. However, the metabolism and kinds of recognition of the sterol molecule, in terms of uptake and effects on growth and induction of the various sexual events, contrast sharply with what is known for other oomycetous fungi such as Achlya and Saprolegnia. This implies that the evolutionary histories of the Oomycetes may be different.  相似文献   
54.
Summary With 158 victims, the fire on board the Scandinavian Star was one of the world's worst ferry disasters. A team of identification experts, including dentists, were employed to secure evidence for identification and to remove the victims from the ferry. Four parallel teams, each with 2 dentists, examined and autopsied the victims at the Institute of Forensic Medicine, University of Oslo. Using the INTERPOL Disaster Victim Identification forms and aided by computers, all victims were identified within 17 days. Dental identity could be established in 107 cases (68%).  相似文献   
55.
The extracts of sixty Korean plants were evaluated for their biological activities such as antitumor activities against Sarcoma 180, Leukemia SN-36 and Ehrlich ascites carcinoma, antimicrobial activities and behavioral observation in mice. The results are tabulated.  相似文献   
56.
目的 研究老年人脑梗塞继发性癫痫的发生率及发作时间 ,发作类型 ,癫痫发作与病变部位的关系、治疗与转归。方法 总结分析 5 6例老年人脑梗塞继发癫痫的临床、CT资料。结果 癫痫病发生率 9 0 % ;分别为早期癫痫与迟发性癫痫 ,而以迟发性癫痫为主 3 9例 (70 9% ) ;发作类型以局限运动为发作为主 3 6例 (64 9% ) ;癫痫发作与病变部位有关 ,病变多位于大脑半球叶 42例 (75 9% ) ,而以额叶为主。结论 老年人脑梗塞继发癫痫发病率高 ,经抗癫痫药物治疗 ,绝大多数能控制  相似文献   
57.
The toxic effects of a gas depend on the time of exposure, concentration and its chemical nature. Pressurized liquids and gases exert an additional cold thermal injury and this may complicate the clinical picture. A patient who had an accidental exposure to liquid ammonia over a prolonged period, manifesting in cutaneous, respiratory and ocular damage in addition to a severe cold thermal injury (frostbite) with a fatal outcome is presented. The patient had flaccid quadriparesis and episodes of bradycardia, which has not been reported previously. These manifestations raise the possibility of the systemic toxicity in patients with prolonged exposure to ammonia.  相似文献   
58.
STUDY DESIGN: A prospective randomized clinical trial. OBJECTIVE: To compare the effectiveness of 2 physical therapy treatment approaches for impingement syndrome of the shoulder. BACKGROUND: Manual physical therapy combined with exercise is a commonly applied but currently unproven clinical treatment for impingement syndrome of the shoulder. METHODS AND MEASURES: Thirty men and 22 women (age 43 years +/- 9.1) diagnosed with shoulder impingement syndrome were randomly assigned to 1 of 2 treatment groups. The exercise group performed supervised flexibility and strengthening exercises. The manual therapy group performed the same program and received manual physical therapy treatment. Both groups received the selected intervention 6 times over a 3-week period. The testers, who were blinded to group assignment, measured strength, pain, and function before treatment and after 6 physical therapy visits. Strength was a composite score of isometric strength tests for internal rotation, external rotation, and abduction. Pain was a composite score of visual analog scale measures during resisted break tests, active abduction, and functional activities. Function was measured with a functional assessment questionnaire. The visual analog scale used to measure pain with functional activities and the functional assessment questionnaire were also measured 2 months after the initiation of treatment. RESULTS: Subjects in both groups experienced significant decreases in pain and increases in function, but there was significantly more improvement in the manual therapy group compared to the exercise group. For example, pain in the manual therapy group was reduced from a pretreatment mean (+/- SD) of 575.8 (+/- 220.0) to a posttreatment mean of 174.4 (+/- 183.1). In contrast, pain in the exercise group was reduced from a pretreatment mean of 557.1 (+/- 237.2) to a posttreatment mean of 360.6 (+/- 272.3). Strength in the manual therapy group improved significantly while strength in the exercise group did not. CONCLUSION: Manual physical therapy applied by experienced physical therapists combined with supervised exercise in a brief clinical trial is better than exercise alone for increasing strength, decreasing pain, and improving function in patients with shoulder impingement syndrome.  相似文献   
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