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41.
At present there is much interest in the cell tropism and host range of influenza viruses, especially those of the H5N1 subtype. We wished to develop a method that would enable investigation of attachment of infectious virus through the interaction of the hemagglutinin molecule and live mammalian and avian cells and the subsequent infection of these cells. To this end, influenza viruses of various HA subtypes were constructed that either carry the green fluorescent protein (GFP) instead of the neuraminidase protein, or that express GFP in the cytoplasm of infected cells. The HA genes were derived from influenza viruses A/PR/8/34 (H1N1), A/Netherlands/178/95 (H3N2) and A/Vietnam/1194/04 (H5N1). Using these pairs of viruses, attachment and post-attachment events in the virus replication cycle can be distinguished. In general, the expression of NeuAc(alpha2-3)Gal or NeuAc(alpha2-6)Gal receptors on the cells tested corresponded with the attachment of the viruses that were studied with respect to predicted receptor specificity. Virus attachment was not always predictive for efficient infection of the cells.  相似文献   
42.
The prevalence of atopic diseases, including eczema, allergic rhinoconjunctivitis and asthma, has increased worldwide, predominantly in westernized countries. Recent epidemiological studies and experimental research suggest that microbial stimulation of the immune system influences the development of tolerance to innocuous allergens. The gastrointestinal microbiota composition may be of particular interest, as it provides an early and major source of immune stimulation and seems to be a prerequisite for the development of oral tolerance. In this review the observational studies of the association between the gut microbiota and atopic diseases are discussed. Although most studies indicated an association between the gut microbiota composition and atopic sensitization or symptoms, no specific harmful or protective microbes can be identified yet. Some important methodological issues that have to be considered are the microbiological methods used (traditional culture vs molecular techniques), the timing of examining the gut microbiota, the definition of atopic outcomes, confounding and reverse causation. In conclusion, the microbiota hypothesis in atopic diseases is promising and deserves further attention. To gain more insight into the role of the gut microbiota in the etiology of atopy, large-scale prospective birth cohort studies using molecular methods to study the gut microbiota are needed.  相似文献   
43.
The Athlete Biological Passport (ABP) refers to the collection of data related to an individual athlete. The ABP contains the Haematological Module and the Steroidal Module, which are used for the longitudinal monitoring of variables in blood and urine, respectively. Based on changes in these variables, a statistical model detects outliers which indicate doping use and guide further targeted testing of the athlete. Presently, athletes can access their data of the Haematological Module in the Anti‐Doping Administration and Management System (ADAMS). However, granting athletes access to this data has been a matter of debate within the anti‐doping community. This article investigates whether an athlete has a right to access the contents of their ABP profile. We approached this discussion by comparing the nature of ABP data with that of forensic and medical data and touched on important concerns with ABP data disclosure to athletes such as potentially allowing for the development of alternative doping techniques to circumvent detection; and making athletes vulnerable to pressure by the media to publicly release their data. Furthermore, given that ABP data may contain medically relevant information that can be used to diagnose disease, athletes may over‐interpret its medical significance and wrongly see it as a free health check. We argue that safeguarding the integrity of the ABP system must be seen as the most essential element and thus a departure from immediate data disclosure is necessary. Two different strategies for delayed data disclosure are proposed which diminish the chances of ABP data being misused to refine doping techniques.  相似文献   
44.

Background

When peritoneal carcinomatosis (PC) is diagnosed during emergency surgery for colorectal cancer (CRC), further treatment with curative intent may seem futile given the known poor prognosis of both PC and emergency surgery. The aim of the current study was to investigate the feasibility and effectiveness of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for CRC patients who previously underwent emergency surgery in the presence of PC.

Methods

All patients with synchronous PC of CRC referred to two tertiary centers between April 2005 and November 2013 were included in this study. Operative, postoperative and survival details were compared between patients presenting in an emergency or elective setting.

Results

In total, 149 patients with synchronous PC underwent CRS and HIPEC. Amongst these patients, 36 (24.2 %) initially presented with acute symptoms requiring emergency surgery. Acute presentation did not result in a longer interval between the initial operation and HIPEC (2.2 vs. 2.1 months; P = 0.09). When comparing operative outcomes, no significant differences were found in blood loss (P = 0.47), operation time (P = 0.39), or completeness of cytoreduction (P = 0.97). In addition, complication rates, degree and types of complication did not differ between the groups. Median survival was 36.1 months for emergency presentation compared with 32.1 in the elective group (P = 0.73).

Conclusion

CRS + HIPEC may be performed safely in patients with PC of colorectal origin presenting with acute symptoms requiring emergency surgery. More importantly, the 5-year survival rate in these patients was equal to elective cases. This should be regarded as promising and therefore considered for these patients.  相似文献   
45.
46.
47.
Predictability and prognosis of PTCA-induced coronary artery aneurysms   总被引:9,自引:0,他引:9  
The natural history of coronary aneurysms, defined as local dilatations exceeding the diameter of the normal adjacent vessel segments by at least 1.5 times, is not significantly different from the natural history of nonaneurysmal coronary disease. However, little is known about the prognosis of percutaneous transluminal coronary angioplasty (PCTA)-induced coronary aneurysms. Therefore, we investigated the occurrence and the medium long-term prognosis of such aneurysms in 728 patients who, after successful PTCA, underwent repeat coronary angiography at mean 4.5 months post-PTCA. A coronary aneurysm at the site of PTCA ws noted in 3.9% of patients (n = 28). Of the potentially predictive factors analyzed, only a coronary dissection at the time of PTCA had statistically significant influence. The long-term prognosis of PTCA-induced coronary aneurysms was excellent. One patient underwent (unrelated) cardiac surgery, all other 27 patients remained eventfree. We conclude that the same benign nature of coronary aneurysmal disease holds true for those aneurysms that develop after PTCA.  相似文献   
48.
49.
The objective of this study was to find differences in outcome and complications using three different types of devices for percutaneous atrial septal defect (ASD) closure in adults. Percutaneous closure of a secundum-type ASD is increasingly performed in adult patients. All adult patients who underwent a percutaneous closure of a secundum-type ASD in our center between November 1996 and November 2004 were included. Failure was defined as dislocation or embolization of the device, which required surgical intervention. Periprocedural and mid-term complications were registered. Sixty-five patients, mean age 45.7+/-18.1 years (18 men, 47 women), underwent a percutaneous closure of an ASD with an ASDOS in 3, an Amplatzer in 36, and a Cardioseal/Starflex closure device in 26 patients. During an overall median follow-up of 1.2 years (range, 0.1-6.7 years), the failure occurred in four patients, all Cardioseal/Starflex (P=0.04). Within the Cardioseal/Starflex subgroup, the ASD and device diameters were significantly higher in those patients in whom the primary endpoint occurred compared to the others, 18.8+/-3.8 vs. 13.0+/-3.8 mm for ASD diameter (P=0.01) and 40 (range, 40-43) vs. 33 mm (range, 20-40) for device diameter (P=0.008). Overall complications were transient arrhythmias in 15.4%, pericardial effusion in 1.5%, and transient ischemic attack in 1.5%. Complete closure 6 months after the procedure occurred in 79.6%, without difference between the devices. Percutaneous ASD closure seems to be a relatively safe and effective procedure. However, using the larger Cardioseal/Starflex devices for closure seems to be related to a higher rate of device dislocation and embolization.  相似文献   
50.

PURPOSE

Family physicians play a pivotal role in providing end-of-life care and in enabling terminally ill patients to die in familiar surroundings. The purpose of this study was to explore the family physicians’ perceptions of their role and the difficulties they have in preventing and guiding hospital admissions at the end of life.

METHODS

Five focus groups were held with family physicians (N= 39) in Belgium. Discussions were transcribed verbatim and analyzed using a constant comparative approach.

RESULTS

Five key roles in preventing and guiding hospital admissions at the end of life were identified: as a care planner, anticipating future scenarios; as an initiator of decisions in acute situations, mostly in an advisory manner; as a provider of end-of-life care, in which competency and attitude is considered important; as a provider of support, particularly by being available during acute situations; and as a decision maker, taking overall responsibility.

CONCLUSIONS

Family physicians face many different and complex roles and difficulties in preventing and guiding hospital admissions at the end of life. Enhancing the family physician’s role as a gatekeeper to hospital services, offering the physicians more end-of-life care training, and developing or expanding initiatives to support them could contribute to a lower proportion of hospital admissions at the end of life.  相似文献   
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