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1.
OBJECTIVES: To develop an immune-competent animal model for mucosally derived squamous cell carcinoma (SCCA). STUDY DESIGN: Fifteen Fischer 344 rats were inoculated with 1, 2, 5, 10, or 20 x 10(6) FAT7 cells in their flanks. The animals were observed for tumor growth and metastasis. RESULTS: All animals developed tumors that grew exponentially. Pulmonary metastases developed in all animals and 13% developed lymph node metastases. CONCLUSION: The FAT7 flank tumor in Fischer 344 rats is a new animal model that closely resembles the behavior of human mucosal head and neck cancer. SIGNIFICANCE: The existence of an immune-competent, mucosally derived, and reliable animal model of SCCA that somewhat resembles human head and neck SCCA gives the opportunity to perform immune-modulating experiments on head and neck cancer in these animals. EBM rating: B-3.  相似文献   
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The aim of this study is to identify the effect of time and pressure of tourniquet in blood pressure and pulse rate immediately after the releasing of tourniquet in the upper and lower extremity of the orthopedic surgeries. This retrospective study examined 206 consecutive patients. Comparisons of the systolic and diastolic pressure and heart rate were made before the induction of anesthesia and tourniquet inflation, and immediately after the deflation. In general, there was no significant difference in hemodynamic changes between the upper- and lower-limb with regard to the type of anesthesia. There was no significant correlation between systolic blood pressure and tourniquet pressure, while by increasing the tourniquet time significantly, the systolic blood pressure decreases immediately after the deflation. Interestingly, the considerable increase in age paralleled with a significant decrease in the systolic blood pressure. The effect of tourniquet time is more than the age. There was no significant correlation between the tourniquet pressure and tourniquet time with diastolic blood pressure. Simply the increase in age significantly paralleled with the mild decrease in diastolic blood pressure Orthopedic surgeons are recommended not to rely on the benefits of tourniquet to raise blood pressure due to hypotensive conditions after the deflation especially in the old.  相似文献   
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Severe hypertension occurred as a postoperative complication after correction of a club-foot deformity in four children (seven feet) who were between the ages of two and three years and had no history of hypertension. The hypertension subsided slowly after administration of antihypertensive medications or more rapidly after release of the correction that had been obtained operatively.  相似文献   
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Lasers in Medical Science - Treatment of cutaneous leishmaniasis (CL) continues to be a health concern, and alternative therapies with fewer side effects are substantially needed. This study aimed...  相似文献   
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Pseudoangiomatous stromal hyperplasia (PASH) is a rare benign breast entity scarcely reported in the medical literature. Its pathogenesis, etiology, and optimal treatment are still unknown. PASH tumors have a broad spectrum of clinical presentations and might be mistaken for malignancies. The authors present six patients diagnosed with PASH.  相似文献   
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ObjectiveWe conducted a systematic review and dose–response meta-analysis of prospective studies to summarize findings on the associations between intakes of soy, soy isoflavones, and soy protein and risk of mortality from all causes, cancers, and cardiovascular diseases.MethodsOnline databases were systematically searched to identify relevant articles published earlier than May 2018. We applied restricted cubic splines using random-effects analysis to assess dose–response associations. Between-study heterogeneity was assessed by I2 value and Cochrane Q test. Potential publication bias was assessed by visual inspection of funnel plots and Begg regression test.ResultsIn total, 23 prospective studies with an overall sample size of 330,826 participants were included in the current systematic review and the meta-analysis. Soy/soy products consumption was inversely associated with deaths from cancers (pooled relative risk 0.88, 95% CI 0.79 to 0.99; P=0.03; I2=47.1%, 95% CI 0.0% to 75.4%) and cardiovascular diseases (pooled effect size: 0.85, 95% CI 0.72 to 0.99; P=0.04; I2=50.0%, 95% CI 0.0% to 77.6%). Such significant associations were also observed for all-cause mortality in some subgroups of the included studies, particularly those with higher quality. In addition, higher intake of soy was associated with decreased risk of mortality from gastric, colorectal, and lung cancers as well as ischemic cardiovascular diseases. Participants in the highest category of dietary soy isoflavones intake had a 10% lower risk of all-cause mortality compared with those in the lowest category. We also found that a 10-mg/day increase in intake of soy isoflavones was associated with 7% and 9% decreased risk of mortality from all cancers and also breast cancer respectively. Furthermore, a 12% reduction in breast cancer death was indicated for each 5-g/day increase in consumption of soy protein. However, intake of soy protein was not significantly associated with all-cause and cardiovascular diseases mortality.ConclusionsSoy and its isoflavones may favorably influence risk of mortality. In addition, soy protein intake was associated with a decreased risk in the mortality of breast cancer. Our findings may support the current recommendations to increase intake of soy for greater longevity.  相似文献   
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Background

Bodybuilding is a demanding sport, which requires high-volume, high-resistance weight training and augmented nutritional intake, toward an increase of overall body muscle mass accompanied by an overall decrease of body fat percentage and mass. Among bodybuilders, the use of various legal and illegal supplements is common. These supplements may be naturally occurring or man-made.

Case Report

We discuss the case of a 30-year-old male bodybuilder presenting with coma due to severe hypoglycemia from unknown cause, necessitating iterative glucose infusions, which was subsequently found to be related to cryptic insulin injections.

Why Should an Emergency Physician Be Aware of This?

In strength athletes, especially amateurs, the recourse to performance-enhancement drugs (e.g., insulin) is frequent. Beyond the specificity of care required for surreptitious insulin intoxication, emergency physicians should be alert to the possibility that exogenous insulin has been injected for use as an ergogenic aid by bodybuilders and others seeking to increase their body muscle mass when they encounter a patient with a decreased level of consciousness and treatment-refractory hypoglycemia. Moreover, in case of suspicion of such intoxication, the use of other illegal supplements should be screened, due to potentially associated risks of complication.  相似文献   
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Memories of the images that we have seen are thought to be reflected in the reduction of neural responses in high-level visual areas such as inferotemporal (IT) cortex, a phenomenon known as repetition suppression (RS). We challenged this hypothesis with a task that required rhesus monkeys to report whether images were novel or repeated while ignoring variations in contrast, a stimulus attribute that is also known to modulate the overall IT response. The monkeys’ behavior was largely contrast invariant, contrary to the predictions of an RS-inspired decoder, which could not distinguish responses to images that are repeated from those that are of lower contrast. However, the monkeys’ behavioral patterns were well predicted by a linearly decodable variant in which the total spike count was corrected for contrast modulation. These results suggest that the IT neural activity pattern that best aligns with single-exposure visual recognition memory behavior is not RS but rather sensory referenced suppression: reductions in IT population response magnitude, corrected for sensory modulation.

Under the right conditions, we are very good at remembering the images that we have seen: we can remember thousands of images after viewing each only once and only for a few seconds (1, 2). How our brains support this remarkable ability, often called “visual recognition memory” (3), is not well understood. The most prominent proposal to date suggests that memories about whether images have been encountered before are signaled in high-level visual brain areas such as inferotemporal cortex (IT) and perirhinal cortex via adaptation-like reductions of the population response to repeated as compared to novel stimuli, a phenomenon referred to as repetition suppression (RS) (49). Repetition suppression exhibits the primary attributes needed to account for the vast capacity of single-exposure visual memory behavior: response decrements in subsequent exposures are selective for image identity (even after viewing an extensive sequence of other images), and last for several minutes to hours (5, 6, 10). RS has also been shown to account for behavior in an image recognition memory task: a linear decoder with positive weights can predict single-exposure visual recognition memory behavior from neural responses in IT cortex (10).Despite the fact that the RS hypothesis is consistent with available evidence, it seems likely to be too simplistic an explanation for visual recognition memory encoding. In particular, it is well known that sensory neurons such as those of IT cortex are modulated not only by image memory, but also by stimulus properties such as image contrast (11). It is thus unclear whether and how these stimulus-induced effects interfere with judgments of whether images are novel or have been encountered before, and if they do not, how image memory can be decoded from neural responses in a way that disambiguates it from changes in these stimulus properties. To investigate this, we measured behavioral and neural responses of monkeys trained to report whether images were novel or repeated while disregarding image contrast (Fig. 1A).Open in a separate windowFig. 1.Visual memory behavior. (A) The contrast-invariant, single-exposure visual memory task. The monkeys viewed a sequence of images and reported whether they were novel (never seen before) or repeated (seen exactly once) while ignoring randomized changes in contrast. Monkeys were trained to saccade to one of two response targets to indicate their choice (red arrows). Images were repeated with a randomly chosen delay between the first and repeated presentation (“n-back”). (B) Images were displayed at one of two contrast levels, yielding two conditions for novel images, high (H) and low (L), and four conditions for repeated images: HH (repeated H preceded by novel H), LL (repeated L preceded by novel L), HL (repeated L preceded by novel H), and LH (repeated H preceded by novel L). The four repeated conditions were organized into same-contrast and mixed-contrast groups depending on whether the initial and repeated presentations were at the same or different contrasts, respectively. (C) Behavioral performance for the data pooled across monkeys in the task, where small black dots indicate average performance for an individual session and large colored dots indicate the average performance across sessions. A measure of contrast invariance, I, was computed as the ratio of the variance across contrast conditions and the variance with respect to the maximally contrast-modulated pattern after taking overall performance into account, subtracted from 1 (SI Appendix, SI Methods). Insets illustrate the expected behavioral pattern with minimal (I = 0) and maximal (I = 1) contrast invariance.  相似文献   
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