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1.
2.
BACKGROUND Kratom is a psychoactive substance that is isolated from the plant Mitragyna speciosa. The leaves can be chewed fresh or dried, smoked, or infused similar to herbal teas. The plant leaves have been used by natives of Southeast Asia for centuries. The substance has been used for its stimulant activity at low doses, and as an opium substitute at higher doses due to a morphine like effect.CASE SUMMARY A 37-year-old female with a history of depression and obesity(body mass index: 32) presented to emergency room with a week-long history of nausea, decreased appetite, fatigue, and two days of jaundice. On admission bilirubin was markedly elevated. Her condition was thought to be due to consumption of Kratom 2 wk before onset of symptoms. Liver biopsy showed changes mimicking primary biliary cholangitis. Patient's symptoms and jaundice improved quickly.CONCLUSION The use of Kratom has been on the rise in recent years across the United States and Europe. Several case reports have associated adverse health impact ofKratom-containing products including death due to its ability to alter levels of consciousness. Only a few case reports have highlighted the hepatotoxic effects of Kratom. Even fewer reports exist describing the detailed histopathological changes.  相似文献   
3.

Background

Multiparametric magnetic resonance imaging (mpMRI) undoubtedly affects the diagnosis and treatment of localized prostate cancer (CaP). However, clinicians need a better understanding of its accuracy and limitations in detecting individual CaP foci to optimize management.

Objective

To determine the per-lesion detection rate for CaP foci by mpMRI and identify predictors of tumor detection.

Design, setting, and participants

We carried out a retrospective analysis of a prospectively managed database correlating lesion-specific results from mpMRI co-registered with whole-mount pathology (WMP) prostatectomy specimens from June 2010 to February 2018. Participants include 588 consecutive patients with biopsy-proven CaP undergoing 3-T mpMRI before radical prostatectomy at a single tertiary institution.

Outcome measurements and statistical analysis

We measured mpMRI sensitivity in detecting individual CaP and clinically significant (any Gleason score ≥7) CaP foci and predictors of tumor detection using multivariate analysis.

Results and limitations

The final analysis included 1213 pathologically confirmed tumor foci in 588 patients with primarily intermediate- (75%) or high-risk (12%) CaP. mpMRI detected 45% of all lesions (95% confidence interval [CI] 42–47%), including 65% of clinically significant lesions (95% CI 61–69%) and nearly 80% of high-grade tumors. Some 74% and 31% of missed solitary and multifocal tumors, respectively, were clinically significant. The majority of missed lesions were small (61.1% ≤1 cm); 28.3% were between 1 and 2 cm, and 10.4% were >2 cm. mpMRI missed at least one clinically significant focus in 34% of patients overall, and in 45% of men with multifocal lesions. On multivariate analysis, smaller, low-grade, multifocal, nonindex tumors with lower prostate-specific antigen density were more likely to be missed. Limitations include selection bias in a prostatectomy cohort, lack of specificity data, an imperfect co-registration process, and uncertain clinical significance for undetected lesions.

Conclusions

mpMRI detects less than half of all and less than two-thirds of clinically significant CaP foci. The moderate per-lesion sensitivity and significant proportion of men with undetected tumor foci demonstrate the current limitations of mpMRI.

Patient summary

Magnetic resonance imaging of the prostate before surgical removal for prostate cancer finds less than half of all individual prostate cancer tumors. Large, solitary, aggressive tumors are more likely to be visualized on imaging.  相似文献   
4.
Journal of Thrombosis and Thrombolysis - Andexanet-alpha is a specific reversal agent for direct factor Xa inhibitors (dFXaI). We aimed to project utilization rates and cost of andexanet for...  相似文献   
5.
Pancreatic adenocarcinoma is a low-incident but highly mortal disease. It accounts for only 3% of estimated new cancer cases each year but is currently the fourth common cause of cancer mortality. By 2030, it is expected to be the 2nd leading cause of cancer death. There is a clear need to diagnose and classify pancreatic cancer at earlier stages in order to give patients the best chance at a definitive cure through surgery. Three precursor lesions that distinctly lead to pancreatic adenocarcinoma have been identified, and we have increasing understanding the non-genetic and genetic risk factors for the disease. With increased understanding about the risk factors, the familial patters, and associated accumulation of genetic mutations involved in pancreatic cancer, we know that there are mutations that occur early in the development of pancreatic cancer and that improved genetic risk-based strategies in screening for pancreatic cancer may be possible and successful at saving or prolonging lives. The remaining challenge is that current standards for diagnosing pancreatic cancer remain too invasive and too costly for widespread screening for pancreatic cancer. Furthermore, the promises of noninvasive methods of detection such as blood, saliva, and stool remain underdeveloped or lack robust testing. However, significant progress has been made, and we are drawing closer to a strategy for the screening and early detection of pancreatic cancer.  相似文献   
6.
The present study was planned to evaluate the position of the mandibular foramen (MF) and the course of the inferior alveolar nerve in 12 right and 14 left cadaveric hemimandibles. The soft tissue including the muscle attachments of the mandible was cleaned and the inferior neurovascular bundle was dissected up to the MF. The distances from the MF to the angle, symphysis menti, 3rd molar, and the lower point of the mandibular notch were measured. The bone was chiseled from its lingual surface to expose the mandibular canal. The distances from the nerve to the alveolar and inferior borders were measured. The distance from the MF to different landmarks did not show any side differences except the one to the symphysis menti (P<0.05; Mann-Whitney 'U' test). Similarly the distances from the nerve to the borders also did not show any significant side differences. These data indicate that, on average, MF is located at a symmetrical point on the ramus on either side, although, not exactly at a fixed distance from any landmarks tested. Further, the canals were located either at near to the middle or below near to the base of the mandible. This study concludes that, the location of the MF varies from bone to bone despite its bilateral symmetry. Further, the canal and consequently the nerve do not maintain a constant position in the mandible.  相似文献   
7.
8.
The leading cause of neonatal mortality, pre-term birth, is often caused by pre-mature ripening/opening of the uterine cervix. Although cervical fibroblasts play an important role in modulating the cervix’s extracellular matrix (ECM) and mechanical properties, it is not known how hormones, i.e., progesterone, and pro-inflammatory insults alter fibroblast mechanics, fibroblast-ECM interactions and the resulting changes in tissue mechanics. Here we investigate how progesterone and a pro-inflammatory cytokine, IL-1β, alter the biomechanical properties of human cervical fibroblasts and the fibroblast-ECM interactions that govern tissue-scale mechanics. Primary human fibroblasts were isolated from non-pregnant cervix and treated with estrogen/progesterone, IL-1β or both. The resulting changes in ECM gene expression, matrix remodeling, traction force generation, cell-ECM adhesion and tissue contractility were monitored. Results indicate that IL-1β induces a significant reduction in traction force and ECM adhesion independent of pre-treatment with progesterone. These cell level effects altered tissue-scale mechanics where IL-1β inhibited the contraction of a collagen gel over 6 days. Interestingly, progesterone treatment alone did not modulate traction forces or gel contraction but did result in a dramatic increase in cell-ECM adhesion. Therefore, the protective effect of progesterone may be due to altered adhesion dynamics as opposed to altered ECM remodeling.  相似文献   
9.

Objective

To evaluate real-time shear wave ultrasound elastography (SWE) for characterizing focal thyroid lesions in routine clinical practice.

Methods

Seventy-four patients with 81 focal thyroid lesions undergoing conventional US with needle cytology also underwent SWE. Absolute and relative SWE stiffness measurements on colour-coded elastograms were correlated with cytology and their discriminatory performances assessed.

Results

Seventeen nodules were malignant (13 papillary, 4 other cancers), 45 benign (43 hyperplastic nodules, 2 focal thyroiditis), 5 indeterminate (“follicular lesions”), and 5 had inadequate cytology. SWE results were higher in malignant than benign nodules (P values 0.02–0.05) although their discriminatory performances were mediocre (AUCs 0.58–0.74). The most accurate SWE cut-off, 34.5 kPa for a 2-mm region of interest, achieved 76.9?% sensitivity and 71.1?% specificity for discriminating papillary cancer from benign nodules. No thresholds produced high sensitivity without lowering specificity appreciably, and vice versa. Nodule size correlated with SWE for benign nodules (P?<?0.01). Intranodular cystic change or calcification did not influence SWE. Qualitatively, elastographic artefacts and foci lacking colour elasticity signal occurred in some solid nodules.

Conclusion

Although malignant nodules are generally stiffer than benign nodules, the precision results do not suggest a definitive role for SWE, at present, in identifying or excluding thyroid malignancy.

Key Points

? Shear wave ultrasound elastography (SWE) offers new insight into thyroid disease. ? Papillary cancers have higher SWE indices (equating to higher stiffness) than benign nodules. ? SWE appears limited in terms of identifying or excluding thyroid malignancy accurately. ? Vertically aligned elastographic artefacts can occur in thyroid SWE. ? Areas lacking SWE colour signal can occur in some solid thyroid nodules.  相似文献   
10.
Isotropic Compton profile of NbB(2) using 20 Ci (137)Cs Compton spectrometer is compared with our theoretical profiles obtained from the density functional theory (DFT) within the first and the second order generalized gradient approximation (GGA) and the hybridization of Hartree-Fock and DFT. A good agreement between GGA based profiles and the experiment validates the applicability of second order GGA in momentum densities. Energy bands, density of states and real space analysis of the experimental profile show metallic character of NbB(2).  相似文献   
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