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151.

Background

SpyGlass® single-operator peroral cholangioscopy appears to be a promising technique to overcome some limitations of conventional peroral cholangioscopy. We aimed to prospectively evaluate the SpyGlass system in a cohort of patients with indeterminate biliary lesions.

Methods

Patients with indeterminate strictures or filling defects at endoscopic retrograde cholangiopancreatography (ERCP) were consecutively enrolled. After SpyGlass visual evaluation, targeted biopsies were taken with the SpyBite® and histopathological assessment was made by two experienced gastrointestinal pathologists. SpyBite-targeted biopsy results were evaluated by assessing agreement with surgical specimens and by evaluation of final, clinical follow-up-based diagnosis.

Results

Fifty-two patients participated in the study. In 7 cases, definite diagnosis (stones, varices) was made by SpyGlass endoscopic evaluation. In 42 of the remaining 45 cases, material suitable for histopathology assessment was provided by the SpyBite. Overall, a definite diagnosis was made in 49 (7 + 42; 94 %) cases. Agreement of SpyBite biopsy results with surgical specimen diagnosis was found in 38/42 (90 %) cases; sensitivity, specificity, and positive and negative predictive values were 88, 94, 96, and 85 %, respectively. Procedure-related complications consisted of one case of mild cholangitis and one case of mild pancreatitis.

Conclusions

In our series, the SpyGlass system allowed adequate biopsy sampling and definite diagnosis with high accuracy in the vast majority of patients with indeterminate biliary lesions. Its use was associated with a low complication rate. Further refinements of the technique are warranted, but the SpyGlass system has the potential to become a diagnostic standard for the assessment of indeterminate biliary lesions.  相似文献   
152.

Background

Strategies to reduce prostate-specific antigen (PSA)–driven prostate cancer (PCa) overdiagnosis and overtreatment seem to be necessary.

Objective

To test the accuracy of serum isoform [−2]proPSA (p2PSA) and its derivatives, percentage of p2PSA to free PSA (fPSA; %p2PSA) and the Prostate Health Index (PHI)—called index tests—in discriminating between patients with and without PCa.

Design, setting, and participants

This was an observational, prospective cohort study of patients from five European urologic centers with a total PSA (tPSA) range of 2–10 ng/ml who were subjected to initial prostate biopsy for suspected PCa.

Outcome measurements and statistical analysis

The primary end point was to evaluate the specificity, sensitivity, and diagnostic accuracy of index tests in determining the presence of PCa at prostate biopsy in comparison to tPSA, fPSA, and percentage of fPSA to tPSA (%fPSA) (standard tests) and the number of prostate biopsies that could be spared using these tests. Multivariable logistic regression models were complemented by predictive accuracy analysis and decision curve analysis.

Results and limitations

Of >646 patients, PCa was diagnosed in 264 (40.1%). Median tPSA (5.7 vs 5.8 ng/ml; p = 0.942) and p2PSA (15.0 vs 14.7 pg/ml) did not differ between groups; conversely, median fPSA (0.7 vs 1 ng/ml; p < 0.001), %fPSA (0.14 vs 0.17; p < 0.001), %p2PSA (2.1 vs 1.6; p < 0.001), and PHI (48.2 vs 38; p < 0.001) did differ significantly between men with and without PCa. In multivariable logistic regression models, p2PSA, %p2PSA, and PHI significantly increased the accuracy of the base multivariable model by 6.4%, 5.6%, and 6.4%, respectively (all p < 0.001). At a PHI cut-off of 27.6, a total of 100 (15.5%) biopsies could have been avoided. The main limitation is that cases were selected on the basis of their initial tPSA values.

Conclusions

In patients with a tPSA range of 2–10 ng/ml, %p2PSA and PHI are the strongest predictors of PCa at initial biopsy and are significantly more accurate than tPSA and %fPSA.

Trial registration

The study is registered at http://www.controlled-trials.com, ref. ISRCTN04707454.  相似文献   
153.

Context

Prostate cancer (PCa) screening to detect early stage PCa has resulted in increased identification of small-volume, low-grade PCa, many of which meet criteria for clinically indolent disease. Nevertheless, there remains some degree of underdetection of high-risk PCa in substantial numbers of men despite current diagnostic strategies.

Objective

To discuss the contemporary role of prostate biopsy (PB), focusing on the indications, techniques, and limitations of current PB techniques and evolving techniques affecting patient care.

Evidence acquisition

A comprehensive Medline search was performed using the medical subject heading search terms prostate cancer, detection, prostate biopsy, significant cancer, and diagnosis, with restriction to the English language. Emphasis was given to publications within the past 5 yr.

Evidence synthesis

Because abnormal digital rectal examination (DRE) and prostate-specific antigen (PSA) tests alone lack specificity for cancer, there is no universal indication for PB. This lack has inspired exploration for a cancer-specific biomarker and prediction tools such as risk calculators. Indication for biopsy should involve a balance between the underdiagnosis of high-risk cancers and the potential risks for the overdetection of clinically insignificant cancers as well as biopsy-related morbidity. Evidence supports the inclusion of laterally directed cores during transrectal ultrasound (TRUS) PB in addition to the traditional sextant pattern, which significantly improves cancer detection without a demonstrable increase in morbidity. These data indicate that such PB templates, typically 12 cores, represent the optimal template in initial PB. Optimised techniques and templates for repeat PB remain controversial. However, debate continues regarding indications, sampling number, and location as well as on the potential of modern image-guided approaches or three-dimensional (3D) mapping biopsy in this unique setting. Additional limitations of repeat PB techniques include associated procedural risks if general anaesthesia is required and inherent sampling errors of template-based techniques that are not targeted to the specific tumour site.

Conclusions

Current data support the utility of extended PB templates for initial TRUS PB intended to detect clinically significant PCa. Repeat PB in the setting of prior negative PB on the grounds of clinical suspicion or for risk-stratified approaches to management of low risk PCa requires balancing overdetection of low-risk cancer with the potential to miss significant cancer. Several options, including modern image-guided targeting, biomarker development, transrectal saturation PB, and 3D template mapping PB, are changing the clinical paradigms for evaluation and management. Evidence to support adopting approaches other than the current established standards should be tested through appropriately designed prospective studies.  相似文献   
154.
The aquaporin-2 (AQP2) plays a key role in AVP-induced absorption of water, and its urinary excretion is related to its function. We aimed to test if the assumption of water with different mineral content can modify the expression of AQP2, leading to a change in AQP2 urinary concentration, in 20 healthy young subjects. Each subject received an oral water load (LM or HM) of 250 mL/hour for four hours, and several variables were measured. Plasmatic osmolality after water assumption was significantly reduced with no differences after the low (LM) or the high mineral (HM) water load. Urinary osmolality and plasmatic vasopressin concentration were significantly reduced after an assumption of both kinds of water. However, serum vasopressin was lower after HM water assumption than after LM. AQP2 urinary excretion was significantly reduced after water assumption with respect to the basal level and it was lower after LM than after HM water assumption. The different mineral content of water was investigated as a factor contributing to the development of hypertension. Considering that AQP2 can play a role in pathogenesis of hypertension, our demonstration that AVP-mediated AQP2 urinary excretion is strictly influenced by the consumption of water with different mineral content suggests a new, interesting field of investigation related to the link between blood pressure alterations and nutritional habits.  相似文献   
155.
Venous ulcers are related to dysfunctions in extracellular matrix. Both matrix metalloproteinases (MMP) and neutrophil gelatinase‐associated lipocalin (NGAL) could play a role in the healing process in patients with chronic venous ulcers. We evaluated the role of MMP‐9 and NGAL in the healing process in venous ulceration. We performed an open‐label, parallel groups, single clinical center study. Patients with chronic venous leg ulcers represented the test group (Group I), whereas patients without chronic ulcers represented the control group (Group II). In Group I plasma and wound fluid samples were collected at the time of admission, at the time of the surgery, and at the follow‐up, while ulcer tissues were taken at the time of the surgery. In Group II, plasma and wound fluid were collected at admission and at the time of the surgery, whereas skin tissues were collected at the time of the surgery. Enzyme‐linked immunosorbent assay test was used to evaluate the levels of MMP‐9 and NGAL in plasma and wound fluid, whereas Western blot analysis was performed to estimate the expression of MMP‐9 and NGAL in tissues. Enzyme‐linked immunosorbent assay tests revealed significantly higher levels of MMP‐9 and NGAL in both plasma and wound fluid of patients with ulcers compared to patients without ulcers (p < 0.01). Moreover, Western blot analysis documented an increased expression of MMP‐9 and NGAL in biopsy tissue of patients with ulcers compared to patients without ulcers (p < 0.01). In conclusion MMP‐9 and NGAL may correlate with the clinical course of venous ulcers.  相似文献   
156.
157.
158.
Tardive dyskinesia (TD) is an involuntary movement disorder that can occur in up to 25% of patients receiving long-term first-generation antipsychotic treatment. Its etiology is unclear, but family studies suggest that genetic factors play an important role in contributing to risk for TD. The vesicular monoamine transporter 2 (VMAT2) is an interesting candidate for genetic studies of TD because it regulates the release of neurotransmitters implicated in TD, including dopamine, serotonin, and GABA. VMAT2 is also a target of tetrabenazine, a drug used in the treatment of hyperkinetic movement disorders, including TD. We examined nine single-nucleotide polymorphisms (SNPs) in the SLC18A2 gene that encodes VMAT2 for association with TD in our sample of chronic schizophrenia patients (n = 217). We found a number of SNPs to be nominally associated with TD occurrence and the Abnormal Involuntary Movement Scale (AIMS), including the rs2015586 marker which was previously found associated with TD in the CATIE sample ( Tsai et al., 2010), as well as the rs363224 marker, with the low-expression AA genotype appearing to be protective against TD (p = 0.005). We further found the rs363224 marker to interact with the putative functional D2 receptor rs6277 (C957T) polymorphism (p = 0.001), supporting the dopamine hypothesis of TD. Pending further replication, VMAT2 may be considered a therapeutic target for the treatment and/or prevention of TD.  相似文献   
159.
A 24-year-old woman complained of a 4-year history of muscle cramps, stiffness of the right lower limb and walking difficulties. After clinical and laboratory investigations, a diagnosis of multiple sclerosis was made. However, her family history revealed that her father and an older sister had lifelong symptoms of impaired muscle relaxation following contraction, improving with physical exercise. Molecular genetic studies in both sisters confirmed the diagnosis of myotonia congenita, due to a c.568GG>TC (Gly190Ser) pathogenic mutation in CLCN1 gene. Occurrence of two different neurological conditions in the same patient, both manifesting with stiffness, is quite unusual and suggests the opportunity of an accurate differential diagnosis.  相似文献   
160.
Abstract

This study investigated the somatic underpinning of empathy using an interpersonal physiology approach. Thirty-nine dyads were formed by a “pseudo-patient” and a “listener” (a therapist, a psychologist, or a non-therapist). Dyadic physiological concordance in electrodermal responses and listeners' empathy were evaluated during simulations of clinical sessions. A significant positive correlation between empathy as perceived by pseudo-patients and physiological concordance was found, providing empirical evidence of a somatic underpinning of empathy. Moreover, therapists showed higher levels of physiological concordance and empathy, confirming the importance of psychotherapy training in managing clinical interactions.  相似文献   
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