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91.
Carcinoma originating in bone is uncommon; most of them apparently arise in odontogenic cysts. In this paper, we report an extremely rare case in which, verrucous carcinoma originated from an odontogenic cyst. This lesion was firm and non-tender on palpation and had a white-pink appearance. It was encased in the anterior aspect of the maxilla and exhibited microscopic features of verrucous carcinoma of the oral mucosa. After surgical enucleation, no recurrence or metastasis has been observed up to now. It is mandatory to correlate the clinical and histopathologic findings to establish a true diagnosis.  相似文献   
92.
Although the incidence of ocular trauma has been clearly described in developed countries, few published data are available on the epidemiology and the effects of parameters that can influence the incidence and severity of ocular injuries in Iran. The present study tried to determine epidemiological aspects of ocular traumatic injuries and evaluate their effects on different types of ocular injury. The case series included 1950 consecutive patients with acute ophthalmic trauma presented to the emergency ward of Farabi Hospital in Tehran. Information was collected by interviewing patients and having them fill in a questionnaire. The final diagnosis was made by a medical resident. If there was a difficulty or doubt in diagnosis or classification, confirmation of diagnosis was made by senior faculty. Ocular injuries were classified into globe and non-globe injuries according to the site of injury. Mechanical globe injuries were classified according to Birmingham Eye Trauma Terminology (BETT) into closed and open injuries. The mean age of patients was 28.8 ± 12.8 years; 87.6% were male. The most common causes of injury were work-related (49.0%) and chance events (42.0%). The most frequent ocular injury was globe injury (95.6%), including mechanical (77.6% closed and 5.9% open), chemical (7.6%), photic (2.3%) and thermal (2.2%) injuries. Non-globe injury also occurred in 10.8% of patients; both globe and non-globe injuries occurred in 6.5% of patients. The hospitalization rate in all patients was 8.8%. Previous history of eye trauma was significantly more common in the group with isolated globe injuries (P < 0.001). History of eye trauma is a risk factor for globe injuries and female gender is a risk factor only for non-globe injuries. These two factors may predict future eye injury and increase its risk by 5.2 and 1.6 times, respectively.  相似文献   
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OBJECTIVES: Information technology is a rapidly expanding branch of science which has affected other sciences. One example of using information technology in medicine is the Electronic Medical Records system. One medical university in Iran decided to introduce such system in its hospital. This study was designed to identify the factors which influence the quality of medical documentation when paper-based records are replaced with electronic records. METHODS: A set of 300 electronic medical records was randomly selected and evaluated against eleven checklists in terms of documentation of medical information, availability, accuracy and ease of use. To get the opinion of the care-providers on the electronic medical records system, ten physicians and ten nurses were interviewed by using of semi-structured guidelines. The results were also compared with a prior study with 300 paper-based medical records. RESULTS: The quality of documentation of the medical records was improved in areas where nurses were involved, but those parts which needed physicians' involvement were actually worse. High workloads, shortage of bedside hardware and lack of software features were prominent influential factors in the quality of documentation. The results also indicate that the retrieval of information from the electronic medical records is easier and faster, especially in emergency situations. CONCLUSIONS: The electronic medical records system can be a good substitute for the paper-based medical records system. However, according to this study, some factors such as low physician acceptance of the electronic medical record system, lack of administrative mechanisms (for instance supervision, neglecting physicians and/or nurses in the development and implementation phases and also continuous training), availability of hardware as well as lack of specific software features can negatively affect transition from a paper-based system to an electronic system.  相似文献   
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96.

Background

Glioblastoma multiforme is the most common lethal brain tumor in human adults, with no major therapeutic breakthroughs in recent decades. Research is based mostly on human tumor cell lines deprived of their organotypic environment or inserted into immune-deficient animals required for graft survival. Here, we describe how glioblastoma specimens obtained from surgical biopsy material can be sectioned and transferred into cultures within minutes.

Methods

Slices were kept in 6-well plates, allowing direct observation, application of temozolomide, and irradiation. At the end of experiments, slice cultures were processed for histological analysis including hematoxylin-eosin staining, detection of proliferation (Ki67), apoptosis/cell death (cleaved caspase 3, propidium iodide), DNA double-strand breaks (γH2AX), and neural subpopulations. First clinical trials employed irradiation with the heavy ion carbon for the treatment of glioblastoma patients, but the biological effects and most effective dose regimens remain to be established. Therefore, we developed an approach to expose glioblastoma slice cultures to 12C and X-rays.

Results

We found preservation of the individual histopathology over at least 16 days. Treatments resulted in activation of caspase 3, inhibition of proliferation, and cell loss. Irradiation induced γH2AX. In line with clinical observations, individual tumors differed significantly in their susceptibility to temozolomide (0.4%–2.5% apoptosis and 1%–15% cell loss).

Conclusion

Glioblastoma multiforme slice cultures provide a unique tool to explore susceptibility of individual tumors for specific therapies including heavy ions, thus potentially allowing more personalized treatments plus exploration of mechanisms of (and strategies to overcome) tumor resistance.  相似文献   
97.
98.
Resection of the petrous temporal bone to various degrees provides different levels of access to lesions of the posterior fossa. However, regarding the numerous variations, precise distances of petrosal bone are not still clearly described. This may lead to serious complications during transpetrosal surgeries. Our objective was to evaluate different distances of temporal bone landmarks in order to assess their variations and the possible correlations between them. This anatomical study was performed on 60 temporal bones from 60 human cadavers in the years 2006 and 2007. All the bones contained an adequate portion of the petrous apex and attached fossa dura. Twelve landmarks were defined and 27 different distances were measured for each temporal bone using two-point caliper. Less variation was observed in the superoinferior diameter of horizontal carotid canal with the less coefficient of variation (CV) of 9.29; whereas, the most variation was detected in the inferior (axial) plane of posterior semicircular canal to superior plane of jugular bulb (CV = 57.65). There was a significant correlation between vertical intratemporal diameter of carotid in pyramidal direction, and superior–inferior diameter of horizontal carotid canal (r Pearson = 0.500, P < 0.001). Other significant correlations were also found between other distances. The variations of different distances and landmarks were evaluated and many significant correlations were demonstrated between them which could potentially aid ENT specialists and neurosurgeons in order to approach anatomical landmarks and cranial fossas more safely during otologic and neurotologic surgeries. It could also help the design of middle ear prosthesis.  相似文献   
99.
100.

OBJECTIVE

To determine if baseline subgroups in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial can be identified for whom intensive compared with standard glycemia treatment had different effects on all-cause mortality.

RESEARCH DESIGN AND METHODS

Exploratory post hoc intention-to-treat comparisons were made between intensive and standard glycemia groups on all-cause mortality by subgroups defined by baseline characteristics.

RESULTS

There were few significant interactions between baseline characteristics and effects of intensive versus standard glycemia treatment on mortality: self-reported history of neuropathy (hazard ratio [HR] 1.95, 95% CI 1.41–2.69) versus no history of neuropathy (0.99, 0.79–1.26; P value for interaction 0.0008), higher A1C (A1C >8.5%: HR 1.64, 95% CI 1.22–2.22; A1C 7.5–8.4%: 1.00, 0.75–1.34; A1C <7.5%: 1.00, 0.67–1.50; P value for interaction 0.04), and aspirin use (HR 1.45, 95% CI 1.13–1.85, compared with 0.96, 0.72–1.27, in nonusers; P value for interaction 0.03).

CONCLUSIONS

We found a remarkable similarity of effect from intensive compared with standard glycemia treatment on mortality across most baseline subgroups. No differential effect was found in subgroups defined by variables anticipated to have an interaction: age, duration of diabetes, and previous history of cardiovascular disease. The three baseline characteristics that defined subgroups for which there was a differential effect on mortality may help identify patients with type 2 diabetes at higher risk of mortality from intensive regimens for glycemic control. Further research is warranted.Numerous epidemiological studies have demonstrated a relationship between elevated A1C and a greater risk of cardiovascular (CVD) events and mortality in type 2 diabetes (13). Therefore, it has been hypothesized that a reduction to near-normal levels of A1C in patients with type 2 diabetes would reduce the risk of these adverse outcomes. Three large randomized controlled clinical trials testing this hypothesis in individuals with longstanding type 2 diabetes reported their main results in the past 2 years (46).The Data Safety Monitoring Board of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial discontinued the intensive glycemia arm because of an increase in all-cause mortality in the intensive glycemia arm compared with the standard glycemia arm. The finding of excess mortality in the intensive arm of the ACCORD trial has led to controversy about implementation of intensive glucose control in patients with type 2 diabetes (7,8). Adding to the controversy were results of the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) and Veterans Affairs Diabetes Trial (VADT), demonstrating that although there was no significant reduction in the primary end point of CVD events, there was no increase in mortality with the intensive glycemia arm compared with the standard glycemia arm (4,6), which has raised questions about reasons for these discrepancies (912).A critical question relates to the applicability and generalizability of the conclusions of the ACCORD trial to the broader population or to specific subgroups of patients with type 2 diabetes. Indeed, prespecified subgroup analyses in ACCORD did suggest a significant benefit of intensive glycemic control on CVD events in those participants with lower A1C at entry or absence of CVD event by history, but there was no suggestion of a differential effect on mortality (5). However, these observations are based on only a few subgroup analyses at the time of the primary publication. The effect on mortality of intensive compared with standard glycemia treatment may have been modified by other possible characteristics of patients at entry. We have therefore carried out exploratory post hoc analyses of the effects of intensive compared with standard glycemia treatment in ACCORD participants categorized by various baseline characteristics on all-cause mortality at the time of discontinuation of the intensive glycemia treatment of ACCORD, with the goal to determine if particular subgroups at higher or lower risk from the intensive intervention can be identified.  相似文献   
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