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1.
Research into the results of resection of hilar bile duct cancer   总被引:31,自引:0,他引:31  
E J Boerma 《Surgery》1990,108(3):572-580
We found mentions of 581 resections of hilar bile duct cancer in the literature to January 1989. Resection in 499 patients, reported or updated since 1980, resulted in an operative mortality of 12% and a 5-year survival rate of 13%. Resections confined to the hepatic duct confluence or extended to the quadrate lobe led to an 8% operative mortality and a 7% 5-year survival rate, although resections combined with major liver resection gave a 15% operative mortality and a 17% 5-year survival rate. Despite the best treatments available, present-day resection modalities are usually still not radical. Extension of resection in the retrohilar and hepatoduodenal direction might further improve the long-term surgical results.  相似文献   
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Immortalized cell lines offer significant logistical advantages over primary cells when used for in-vitro studies. Immortalized cells may, however, exhibit important differences relative to their primary cell counterparts. In this study, microarrays were used to make a genome-wide comparison between primary human umbilical vein endothelial cells (HUVECs) and EA.hy926, an immortalized HUVEC cell line, in their baseline properties and in their response to inhibition of the mevalonate pathway with an inhibitor of hydroxy methylglutaryl-coenzyme A reductase (statin). HUVECs and EA.hy926 were incubated with control medium, atorvastatin, mevalonate, or a combination of atorvastatin and mevalonate for 24 h. Gene expression profiles were obtained in duplicates using Affymetrix Human Genome U133A 2.0 arrays (Santa Clara, California, USA). Probe-sets were selected according to the following criteria: a twofold or greater increase/decrease in atorvastatin-treated cells compared with untreated cells; a twofold or greater reversal of the effect of atorvastatin by combined treatment with atorvastatin and mevalonate; no significant change in gene expression in cells treated with mevalonate alone compared with untreated cells. Most genes that were expressed by untreated HUVECs, were also expressed by untreated EA.hy926 cells. EA.hy926 cells, however, constitutively expressed a large number of additional genes, many of which were related to cell cycle control and apoptosis. Atorvastatin induced differential expression (> or = twofold) of 103 genes in HUVECs (10 up, 93 down) and 466 genes in EA.hy926 cells (198 up, 268 down). Applying the above selection criteria, thrombomodulin and tissue plasminogen activator were up-regulated in both cell types, whereas, connective tissue growth factor, thrombospondin-1, and cysteine-rich angiogenic inducer 61 were down-regulated. In conclusion, EA.hy926 cells retain most of the characteristics of endothelial cells under baseline conditions as well as after treatment with atorvastatin. It is necessary, however, to carefully select and validate changes in genes that are the focus of studies when using EA.hy926 cells. While this cell line is highly useful in studies on some genes, including genes encoding molecules involved in regulating thrombohemorrhagic homeostasis, they appear to be less suited for studies focused on other genes, particularly those involved in the regulation of cell proliferation and apoptosis.  相似文献   
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Summary— In the present study we have compared the steady state biopharmaceutic characteristics of four diltiazem once daily controlled release capsules: Mono-Tildiem LP 300® (300 mg), Adizem® XL (300 mg)1, Cardizem® (300 mg) and Dilacor® (240 mg). Sixteen healthy male volunteers (aged 22.9 ± 3.3 years, range 19–31 years) completed an open label, multiple oral dose, randomized, four-period crossover study without a washout period in between. The volunteers received each diltiazem formulation once daily for four days. Trough diltiazem and metabolites plasma concentrations were determined on days 3 and 4. The 24-h plasma concentration-time profiles were assessed after the dose on day 4 of each period. The following steady state pharmacokinetic parameters for diltiazem were calculated: the minimum plasma concentration (cmin), the maximum plasma concentration (cmax), the time to reach that concentration (tmax), the time interval during which the plasma concentration exceeds 50% of cmax (t50), the area under the plasma concentration-time curve (AUC72–96) and the peak-to-trough fluctuation (PTF). For the metabolites of diltiazem, N-mono-desmethyl-diltiazem (NDM) and desacetyldiltiazem (DAD), AUC72–96 (AUCNDM and AUCDAD) and the ratio metabolite/parent compound were calculated. Steady state was achieved on day 3. Except one, all controlled release formulations have satisfactory controlled release properties allowing once daily administration. However, significant (P < 0.05) differences were found between the pharmacokinetic characteristics which do not allow exchange of the various formulations. Concentrations well below 50 ng·mL-1 in the morning hours were observed for Dilacor® (240 mg) and Adizem® XL (300 mg), which could be a disadvantage of these formulations as it is well-known that ischaemic events occur at a higher rate during that part of the day. The plasma concentration profiles of NDM and DAD, the major circulating metabolites, parallel the plasma concentration profiles for the parent compound. From a clinical point of view, all treatments were well tolerated.  相似文献   
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The aim of this study was to develop a model to evaluate the retrieval quality of search queries performed by Dutch general practitioners using the printed Index Medicus, MEDLINE on CD-ROM, and MEDLINE through GRATEFUL MED. Four search queries related to general practice were formulated for a continuing medical education course in literature searching. The selected potential relevant citations from the course instructor and the 103 course participants together served as the basic set for the three judges to evaluate for (a) relevance and (b) quality, with the latter based on journal ranking, research design and publication type. Relevant individual citations received a citation quality score from 1 (low) to 4 (high). The overall search quality was expressed in a formula, which included the individual citation quality score of the selected and missed relevant citations, and the number of selected non-relevant citations. The outcome measures were the number and quality of relevant citations and agreement between the judges. Out of 864 citations, 139 were assessed as relevant, of which 44 citations received an individual citation quality score of 1, 76 of 2, 19 of 3 and none of 4. The level of agreement between the judges was 68% for the relevant citations, and 88% for the non-relevant citations. We describe a model for the evaluation of search queries based not only on the relevance, but also on the quality of the citations retrieved. With adaptation, this model could be generalized to other professional users, and to other bibliographic sources.  相似文献   
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AIMS: To define outcome measures for auditing the clinical care of children and adolescents with insulin dependent diabetes mellitus (IDDM) and to assess the benefit of appointing a dedicated paediatric trained diabetes specialist nurse (PDSN). METHODS: Retrospective analysis of medical notes and hospital records. Glycaemic control, growth, weight gain, microvascular complications, school absence, and the proportion of children undergoing an annual clinical review and diabetes education session were assessed. The effect of the appointment of a PDSN on the frequency of hospital admission, length of inpatient stay, and outpatient attendance was evaluated. RESULTS: Children with IDDM were of normal height and grew well for three years after diagnosis, but grew suboptimally thereafter. Weight gain was above average every year after diagnosis. Glycaemic control was poor at all ages with only 16% of children having an acceptable glycated haemoglobin. Eighty five per cent of patients underwent a formal annual clinical review, of whom 16% had background retinopathy and 20% microalbuminuria in one or more samples. After appointing the PDSN the median length of hospital stay for newly diagnosed patients decreased from five days to one day, with 10 of 24 children not admitted. None of the latter was admitted during the next year. There was no evidence of the PDSN affecting the frequency of readmission or length of stay of children with established IDDM. Non-attendance at the outpatient clinic was reduced from a median of 19 to 10%. CONCLUSIONS: Outcome measures for evaluating the care of children with IDDM can be defined and evaluated. Specialist nursing support markedly reduces the length of hospital stay of newly diagnosed patients without sacrificing the quality of care.  相似文献   
8.
The concept of a team approach in primary health care (PHC) is an integral part of the overall PHC strategy and is advocated at many occasions. Its theoretical advantages are multiple, even though very few sound studies exist on the effectiveness of PHC team. The viability of the concept of PHC teams is affected by two groups of factors. The first group is related to (health) manpower problems in developing countries with its underlying economic causes. The second group of factors is associated with the viability of the PHC concept in general. This pertains to decentralization, intersectoral collaboration and community participation which all affect the viability of the concept of PHC teams.  相似文献   
9.
OBJECTIVE: To assess the impact of bile duct injury (BDI) sustained during laparoscopic cholecystectomy on physical and mental quality of life (QOL). SUMMARY BACKGROUND DATA: The incidence of BDI during laparoscopic cholecystectomy has decreased but remains as high as 1.4%. Data on the long-term outcome of treatment in these patients are scarce, and QOL after BDI is unknown. METHODS: One hundred six consecutive patients (75 women, median age 44 +/- 14 years) were referred between 1990 and 1996 for treatment of BDI sustained during laparoscopic cholecystectomy. Outcome was evaluated according to the type of treatment used (endoscopic or surgical) and the type of injury. Objective outcome (interventions, hospital admissions, laboratory data) was evaluated, a questionnaire was filled out, and a QOL survey was performed (using the SF-36). Risk factors for a worse outcome were calculated. RESULTS: Median follow-up time was 70 months (range 37-110). The objective outcome of endoscopic treatment (n = 69) was excellent (94%). The result of surgical treatment (n = 31) depended on the timing of reconstruction (overall success 84%; in case of delayed hepaticojejunostomy 94%). Five patients underwent interventional radiology with a good outcome. Despite this excellent objective outcome, QOL appeared to be both physically and mentally reduced compared with controls (P <.05) and was not dependent on the type of treatment used or the severity of the injury. The duration of the treatment was independently prognostic for a worse mental QOL. CONCLUSIONS: Despite the excellent functional outcome after repair, the occurrence of a BDI has a great impact on the patient's physical and mental QOL, even at long-term follow-up.  相似文献   
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