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51.
This study was designed to compare the growth of Pakistani schoolchildren in the UK with the 1990 UK growth standards. Measurements of height, weight, and sitting height were performed on 785 Pakistani schoolchildren aged 5-14 years with the mean values for each age and sex being plotted on the UK growth standards. The results were expressed as SD scores relative to the 1990 reference data. The mean height for the boys was only 0.2 SD scores below the mean for the new growth standards with the mean height for the girls being 0.4 SD scores below the mean. The mean values for weight and body mass index were 0.3 and 0.5 SD scores less than the mean for boys and girls respectively. This study demonstrates that the growth of Pakistani schoolchildren in the UK is comparable to the 1990 UK growth standards with only minor differences. It is not safe to assume that short stature or low body weight in a Pakistani child is due to his or her ethnic background. 相似文献
52.
Smalley W Shatin D Wysowski DK Gurwitz J Andrade SE Goodman M Chan KA Platt R Schech SD Ray WA 《JAMA》2000,284(23):3036-3039
Context Cisapride, a gastrointestinal tract promotility agent, can cause life-threatening cardiac arrhythmias in patients susceptible either because of concurrent use of medications that interfere with cisapride metabolism or prolong the QT interval or because of the presence of other diseases that predispose to such arrhythmias. In June 1998, the US Food and Drug Administration (FDA) determined that use of cisapride was contraindicated in such patients and informed practitioners through additions to the boxed warning in the label and a "Dear Health Care Professional" letter sent by the drug's manufacturer. Objective To evaluate the impact of the FDA's 1998 regulatory action regarding contraindicated use of cisapride. Design and Setting Analysis of data for the 1-year periods before (July 1997-June 1998) and after (July 1998-June 1999) the regulatory action from the population-based, pharmacoepidemiology research databases of 2 managed care organizations (sites A and B) and a state Medicaid program (site C). Participants Patients with at least 180 days of prior enrollment in 1 of the 3 sites who were prescribed cisapride at least once in the period before (n = 24 840) or after (n = 22 459) regulatory action. Patients could be included in both cohorts. Main Outcome Measures Proportion of cisapride users in each period for whom cisapride use was contraindicated by the product label, based on computerized patient medical encounter records. Results In the year prior to regulatory action, cisapride use was contraindicated for 26%, 30%, and 60% of users in study sites A, B, and C, respectively. In the year after regulatory action, use was contraindicated for 24%, 28%, and 58% of users, a reduction in contraindicated use of approximately 2 per 100 cisapride users at each site. When the analysis was restricted to new users of cisapride after regulatory action, only minor reductions in contraindicated use were found. Conclusion The FDA's 1998 regulatory action regarding cisapride use had no material effect on contraindicated cisapride use. More effective ways to communicate new information about drug safety are needed. 相似文献
53.
Liliana Ala Andrade Renato Z Torres An José Fs Sales Regina Vicentini Gustavo A De Souza 《Pathology oncology research : POR》1998,4(1):44-47
Three cases of intravenous leiomyomatosis (IVL) of the uterus, a rare benign smooth-muscle tumor, are described. A preoperative
diagnosis of IVL was not made in any of the patients, all of which presented with a pelvic mass with the presumptive diagnosis
of leiomyoma. Surgical exploration confirmed the presence of uterine mass and two of the three cases showed extra-uterine
extension into the ovarian or uterine veins. Histological examination demonstrated a fascicular pattern of bland spindle-shaped
smooth-muscle cells, which extended to veins inside the myometrium or to extrauterine veins. This was confirmed by immunohistochemical
stain for desmin and factor VIII. Despite their histological benignity, these lesions have a tendency to metastasize and are
closely related to the conditions called “benign metastasizing leiomyoma” and “intracaval mass and cardiac extension”. The
primary treatment of IVL is hysterectomy and excision of any extrauterine tumor, when technically feasible. Anti-estrogenic
therapy has been suggested as potentially useful in controlling of unresectable tumor. According to the literature, the follow-up
must be long and periodic postoperative ultrasonic or magnetic nuclear resonance imaging studies may be useful in detecting
growth of residual intravascular tumor. 相似文献
54.
Six factorially designed studies evaluated the effects of different schedules of electroconvulsive shocks (ECSs) on alpha-2 adrenoceptor function in the rat brain. Attenuation of the hypomotility response to a clonidine challenge was taken to indicate alpha-2 adrenoceptor downregulation, a putative mediator of antidepressant action. Six daily and six alternate-day ECSs were shown separately to produce this receptor change. Three alternate-day ECSs produced comparable downregulation for a comparable period as six daily ECSs; this suggests that ECS produces time-dependent effects. No changes were elicited with a single ECS, which indicates that a single ECS may not influence alpha-2 receptor function. Three daily ECSs produced brief downregulation, which has implications for receptor dynamics as a function of the ECS schedule. Finally, maintenance ECSs sustained alpha-2 adrenoceptor downregulation over 6 weeks, which suggests a possible neurochemical basis for maintenance electroconvulsive therapy. The clinical relevance and scope for further research are discussed. 相似文献
55.
An investigation of learning during propofol sedation and anesthesia using the process dissociation procedure 总被引:17,自引:0,他引:17
BACKGROUND: Many studies have shown that patients may remember words learned during apparently adequate anesthesia. Performance on memory tests may be influenced by explicit and implicit memory. We used the process dissociation procedure to estimate implicit and explicit memory for words presented during sedation or anesthesia. METHODS: We investigated intraoperative learning in 72 women undergoing pervaginal oocyte collection during propofol and alfentanil infusion. One word list was played once before infusion, another was played 10 times during surgery. Venous blood was taken for propofol assay at the end of the intraoperative list. Behavioral measures of anesthetic depth (eyelash reflex, hand squeeze response to command) were recorded and used to adjust the dose of anesthetic where clinically appropriate. On recovery, memory was assessed using an auditory word stem completion test with inclusion and exclusion instructions. RESULTS: The mean blood propofol concentration was 2.5 microg/ml (median, 2.3 microg/ml; range, 0.7-6.1 microg/ml). Mean alfentanil dose was 2.1 mg (median, 2.0 mg; range, 1.2-3.4 mg). Comparison of target and distractor hits in the inclusion condition showed memory for preoperative words only. However, the process dissociation procedure estimates showed explicit (mean, 0.18; P < 0.001) and implicit (mean, 0.05; P < 0.05) memory for the preoperative words, and a small amount of explicit memory for the intraoperative words (mean, 0.06; 95% confidence interval, 0.01-0.10). Memory performance did not differ between the 17 patients who consistently responded to command and eyelash reflex and the 32 patients who remained unresponsive. Blood propofol concentration and alfentanil dose did not correlate with memory for the intraoperative list. CONCLUSIONS: There was no unprompted recall of surgery, but the process dissociation procedure showed memory for words presented during surgery. This memory was apparently explicit but did not correlate with the measures of depth of anesthesia used. 相似文献
56.
Núbia Boechat Maria de Lourdes G. Ferreira Luiz C. S. Pinheiro Antônio M. L. Jesus Milene M. M. Leite Carlos C. S. Júnior Anna C. C. Aguiar Isabel M. de Andrade Antoniana U. Krettli 《Chemical biology & drug design》2014,84(3):325-332
Malaria is one of the most prevalent parasitic diseases in the world. The global importance of this disease, current vector control limitations, and the absence of an effective vaccine make the use of therapeutic antimalarial drugs the main strategy to control malaria. Chloroquine is a cost‐effective antimalarial drug with a relatively robust safety profile, or therapeutic index. However, chloroquine is no longer used alone to treat patients with Plasmodium falciparum due to the emergence and spread of chloroquine‐resistant strains, which have also been reported for Plasmodium vivax. However, the activity of 1,2,3‐triazole derivatives against chloroquine‐sensitive and chloroquine‐resistant strains of P. falciparum has been reported in the literature. To enhance the anti‐P. falciparum activity of quinoline derivatives, we synthesized 11 new quinoline‐1H‐1,2,3‐triazole hybrids with different substituents in the 4‐positions of the 1H‐1,2,3‐triazole ring, which were assayed against the W2‐chloroquine‐resistant P. falciparum clone. Six compounds exhibited activity against the P. falciparum W2 clone, chloroquine‐resistant, with IC50 values ranging from 1.4 to 46 μm . None of these compounds was toxic to a normal monkey kidney cell line, thus exhibiting good selectivity indexes, as high 351 for one compound ( 11 ). 相似文献
57.
Determination of malondialdehyde-induced DNA damage in human tissues using an immunoslot blot assay 总被引:3,自引:4,他引:3
Leuratti C; Singh R; Lagneau C; Farmer PB; Plastaras JP; Marnett LJ; Shuker DE 《Carcinogenesis》1998,19(11):1919-1924
Malondialdehyde (MDA) is a product of lipid peroxidation and prostaglandin
biosynthesis. It is mutagenic and carcinogenic and the major adduct formed
by reaction with DNA, a highly fluorescent pyrimidopurinone (M1-dG), has
been detected in healthy human liver and leukocyte DNA. Analytical methods
used so far for the detection of M1- dG have not been applied to a large
number of individuals or variety of samples. Often, only a few microg of
DNA from human tissues are available for analysis and a very sensitive
assay is needed in order to detect background levels of M1-dG in very small
amounts of DNA. In this paper, the development of an immunoslot blot (ISB)
assay for the measurement of MI-dG in 1 microg of DNA is described. The
limit of detection of the assay is 2.5 adducts per 10(8) bases. A series of
human samples were analysed and levels of 5.6-9.5 (n = 8) and 3.1-64.3 (n =
42) of M1-dG per 10(8) normal bases were detected in white blood cell and
gastric biopsy DNA, respectively. Results on four human samples were
compared with those obtained using an HPLC/32P-post- labelling (HPLC/PPL)
method previously developed and indicated a high correlation between M1-dG
levels measured by the two assays. The advantages of ISB over other assays
including HPLC/PPL, such as the possibility of analysing 1 microg
DNA/sample and the fact that it is less time-consuming and laborious, means
that it can be more easily used for routine analysis of a large number of
samples in biomonitoring studies.
相似文献
58.
Barros MP Lemos M Maistro EL Leite MF Sousa JP Bastos JK Andrade SF 《Journal of ethnopharmacology》2008,120(3):372-377
Aim of the study
In a previous study, our group described the gastric protective effect of the hydroalcoholic extract of Brazilian green propolis. The main compounds found in Brazilian green propolis include phenolic acids, such as: caffeic, ferulic, p-coumaric and cinnamic acids. This study was therefore carried out to evaluate the antiulcerogenic property of the main phenolic acids found in Brazilian Green Propolis.Material and methods
The anti-ulcer assays were performed using the following protocols: nonsteroidal-antiinflammatory drug (NSAID)-induced ulcer, ethanol-induced ulcer, and stress-induced ulcer. The effects of the phenolic acids on gastric content volume, pH and total acidity, using the pylorus ligated model, were also evaluated.Results
It was observed that treatment using doses of 50 and 250 mg/kg of caffeic, ferulic, p-coumaric and cinnamic acids and positive controls (omeprazol or cimetidine) significantly diminished the lesion index, the total area of the lesion and the percentage of lesion in comparison with the negative control groups. In addition, the percentage of ulcer inhibition was significantly higher in the groups treated with the different phenolic acids, cimetidine or omeprazol, in all the protocols used, compared with the negative control groups. In the model to determine gastric secretion, using ligated pylorus, treatment with phenolic acids and cimetidine reduced the volume of gastric juice and total acidity and significantly increased the gastric pH (p < 0.05), compared with the control group, with the exception of the group treated with 50 mg/kg of p-coumaric acid, in which no significant difference was observed, compared with the control. In relation to the acute toxicity, none sign of toxicity was observed when phenolic acids, used in this study, were administered for rats in dose of 2000 mg/kg.Conclusions
In conclusion, the results of this study show that caffeic, ferulic, p-coumaric and cinnamic acids display antiulcer activity. 相似文献59.
Groppo FC Bergamaschi Cde C Cogo K Franz-Montan M Motta RH de Andrade ED 《Phytotherapy research : PTR》2008,22(8):993-998
Over the past decade, interest in drugs derived from medicinal plants has markedly increased. This study was aimed at a literature review focusing on studies investigating herbal drugs and other natural products, as well as their therapeutic application, side effects and possible drug interactions. Few studies were found to support their rational use in dentistry. Since there is an increasing use of phytotherapeutic agents in dentistry, further studies are needed to evaluate their safety and effectiveness for clinical use. 相似文献
60.
Medina Castro N Moreno Alvarez O Guzmán Huerta M Hernández Andrade E 《Ginecología y obstetricia de México》2007,75(10):621-629
Introduction of Doppler ultrasound in obstetrical practice has changed both management and understanding of several diseases that put at risk women and them fetuses. To establish necessary basics and correctly apply this technique, this review will focus in physical principles, acquisition methods, consistency, and safety issues of Doppler ultrasound, in order to improve precision, accuracy and interpretation of this methodology. 相似文献