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71.
Obesity is linked to the development of cancer. Previous studies have suggested that there is a relationship between bariatric surgery and reduced cancer risk. Data sources were from Medline, Embase, and Cochrane Library. From 951 references, 13 studies met the inclusion criteria (54,257 participants). In controlled studies, bariatric surgery was associated with a reduction in the risk of cancer. The cancer incidence density rate was 1.06 cases per 1000 person-years within the surgery groups. In the meta-regression, we found an inverse relationship between the presurgical body mass index and cancer incidence after surgery (beta coefficient ?0.2, P?相似文献   
72.
Ejaculated mammalian spermatozoa acquire competence to fertilize oocytes by a two-step process: capacitation followed by acrosome reaction. The biochemical and biophysical modifications occurring in vivo in the female reproductive tract can be reproduced in vitro, and previous studies have suggested a capacitative role for adenosine A(1) receptor (A(1)R). Mice with a targeted disruption of the Adora 1 gene (A(1)R-/- mice) provide a useful model for better understanding the role of the A(1)R in fertility. Murine spermatozoa express A(1)R in the head, neck, midpiece region, and tail. The number of capacitated spermatozoa incubated in human tubal fluid was significantly reduced in A(1)R-/- compared with A(1)R+/+ and A(1)R+/- spermatozoa. The difference between A(1) R+/+ and A(1)R-/- mouse spermatozoa was mainly in the time necessary to reach the maximum percentage of capacitation. A(1)R+/+ murine sperm obtained the full state of capacitation within 90 minutes whereas A(1)R-/- sperm required 240 minutes. Caffeine, a known antagonist of A(1) and A(2A) adenosine receptors, lowered the number of capacitated sperm and affected the time of capacitation in a dose-dependent manner, mimicking the effects of the lack of A(1) receptors. Although number, motility, and viability of A(1)R-/- murine sperm was not significantly different from A(1)R+/+ mouse spermatozoa, a significant reduction of the number of pups produced by A(1)R-/- male mice suggests that A(1) receptors must be fully operative to accomplish the optimal degree of capacitation and thereby fertilization.  相似文献   
73.

Background

The request to lose weight is expanding not only in obese and morbidly obese patients but also in overweight patients affected by co-morbidities as diabetes and hypertension and who do not tolerate diet regimen or lifestyle changes. The aim of this study is a multicenter evaluation of outcomes of intragastric balloon in overweight patients.

Methods

Patients (BMI 27–30 kg/m2) treated with a BioEnterics Intragastric Balloon (BIB) between 1996 and 2010 were extracted from the database of the participating centres in Rome (Italy), Liège (Belgium) and Madrid (Spain). Primary endpoints were the efficacy and safety at 6 and 42 months from balloon positioning. Secondary endpoints included resolution of co-morbidities.

Results

A total of 261 patients were included in this study. The most common indication for balloon placement was a psychological disorder (54 %). Mean body mass index (BMI) fell from 28.6?±?0.4 at baseline to 25.4?±?2.6 kg/m2 at 6 months and to 27.0?±?3.1 kg/m2 at 3 years from BIB removal. The mean %EWL was 55.6 % at 6 months and 29.1 % at 3 years. Forty-seven patients (18 %) had complications associated with placement of the intragastric balloon (leak?=?28, intolerance?=?14, duodenal ulcer?=?2, gastritis?=?1, oesophagitis?=?1, duodenal polyps?=?1). The rate of patients with hypertension decreased from 29 % at baseline to 16 % at 3 years. Diabetes decreased from 15 to 10 %, dyslipidaemia decreased from 20 to 18 %, hypercholesterolaemia decreased from 32 to 21 % and osteoarthropathy decreased from 25 to 13 %.

Conclusions

The intragastric balloon is safe and effective in overweight patients, helping to reduce progression to obesity and decreasing the prevalence of a number of important co-morbidities.  相似文献   
74.
Bone homeostasis requires stringent regulation of osteoclasts, which secrete proteolytic enzymes to degrade the bone matrix. Despite recent progress in understanding how bone resorption occurs, the mechanisms regulating osteoclast secretion, and in particular the trafficking route of cathepsin K vesicles, remain elusive. Using a genetic approach, we describe the requirement for protein kinase C–delta (PKCδ) in regulating bone resorption by affecting cathepsin K exocytosis. Importantly, PKCδ deficiency does not perturb formation of the ruffled border or trafficking of lysosomal vesicles containing the vacuolar‐ATPase (v‐ATPase). Mechanistically, we find that cathepsin K exocytosis is controlled by PKCδ through modulation of the actin bundling protein myristoylated alanine‐rich C‐kinase substrate (MARCKS). The relevance of our finding is emphasized in vivo because PKCδ?/? mice exhibit increased bone mass and are protected from pathological bone loss in a model of experimental postmenopausal osteoporosis. Collectively, our data provide novel mechanistic insights into the pathways that selectively promote secretion of cathepsin K lysosomes independently of ruffled border formation, providing evidence of the presence of multiple mechanisms that regulate lysosomal exocytosis in osteoclasts. © 2012 American Society for Bone and Mineral Research.  相似文献   
75.
Video-EEG monitoring with intracranial subdural electrodes is a useful assessment tool for the localization of the epileptogenic zone in patients with drug-resistant focal epilepsy. We aimed at assessing the morbidity related to electrode implantation and the surgical outcome in patients who underwent epilepsy surgery after intracranial EEG monitoring. All patients (N?=?58) admitted to our Epilepsy Surgery Centre for drug-resistant focal epilepsy who underwent resective surgery after intracranial monitoring with subdural electrodes and were followed up for at least 2?years were included in the study. Their mean age was 30.4?years (range 8-60?years), 25 (43?%) were female, and 44 (76?%) had a preoperatively detected structural lesion. The mean duration of invasive recording was 2.3?days (range 1-14?days). Extraoperative ECoG allowed the identification of the epileptogenic focus in all cases. The temporal lobe was involved in 21 (36?%) patients, whereas extratemporal foci were identified in 24 (41?%) patients. Thirteen patients (23?%) had multilobar involvement. Functional brain mapping was performed in 15 (26?%) patients. Transient complications related to electrode implantation occurred in three patients. Among patients with evidence of lesion on preoperative MRI, lesionectomy alone was performed in 12 cases (27?%), while it was combined with tailored cortical resection in the remaining cases. Tailored cortical resection was also performed in patients without evidence of lesion on MRI. After resective surgery, transient neurological deficits occurred in five cases, while another patient experienced permanent lateral homonymous hemianopia. At the last follow-up observation, 34 (57?%) patients were seizure-free (Engel class I). This study suggests that invasive EEG recording with subdural electrodes may be useful and fairly safe for many candidates for epilepsy surgery.  相似文献   
76.

Background

Phosphodiesterase 5 inhibitors (PDE5-Is) are a mainstay in the therapy of erectile dysfunction (ED). The primary end point of clinical efficacy, both in clinical studies and normal practice, is represented by the International Index of Erectile Function (IIEF).

Objective

To evaluate if platelet cyclic guanosine monophosphate (cGMP) could represent a valuable marker for PDE5-I activity in ED.

Design, setting, and participants

The study enrolled 46 patients with psychogenic, organic, and mixed ED (20–71 yr of age; IIEF score <26). Patients were randomized to 6 wk of vardenafil, 5 mg/d at bedtime, or placebo.

Intervention

All patients donated two blood samples, one before starting the protocol and the second after 6 wk of treatment.

Measurements

Platelet cGMP was measured in both placebo and vardenafil groups. All the patients completed the IIEF-Erectile Function (EF) domain and the sexual encounter profile (SEP) and underwent visual sexual stimulation (VSS) coupled with Rigiscan. All the measurements were performed prior to starting the protocol and after the 6 wk of treatment.

Results and limitations

Platelet cGMP production was significantly (p < 0.05) elevated in patients taking 5 mg vardenafil versus placebo. Vardenafil was not superior to placebo in improving IIEF-EF and SEP scores. Conversely, VSS-Rigiscan revealed a significant amelioration (p < 0.028) in the vardenafil group versus placebo. The changes in platelet cGMP level correlated well with VSS-Rigiscan (p = 0.0037) but not with IIEF-EF and SEP.

Conclusions

Platelet cGMP could represent a relatively simple, reliable, and objective biomarker of PDE5-I activity in ED clinical studies. Larger clinical studies are needed to further validate the use, utility, and limits of this assay.  相似文献   
77.

Background/Purpose

Fetal tracheal occlusion (TO) was developed in an attempt to enhance prenatal lung growth and improve survival in fetuses with severe congenital diaphragmatic hernia (CDH). We conducted a randomized, controlled clinical trial in 24 fetuses with severe left CDH (liver herniated into the thorax and low lung-to-head ratio) to compare survival after endoscopic fetal TO vs standard perinatal care (control) and prospectively followed up the 16 survivors (9 control, 7 TO) to compare neurodevelopmental, respiratory, surgical, growth, and nutritional outcomes.

Methods

At 1 and 2 years old, subjects underwent evaluation consisting of medical and neurological history and physical, developmental testing, nutritional assessment, oxygen saturation and pulmonary function testing, chest radiograph, and echocardiogram. Growth and developmental measures were corrected for prematurity. Data were analyzed by Mann-Whitney rank sum test, Fisher's Exact test, and logistic and linear regression.

Results

Infants with TO were significantly more premature at birth (control vs TO, 37.4 ± 1.0 vs 31.1 ± 1.7 weeks; P < .01). Growth failure (z score for weight <2 SDs below mean) was severe in both groups at 1 year of age (control vs TO, 56% vs 86%; P = .31). There was considerable catch-up growth by age 2 years (growth failure: control vs TO, 22% vs 33%; P = .19). There were no differences in other growth parameters. There were also no differences in neurodevelopmental outcome at 1 and 2 years. Supplemental oxygen at hospital discharge was a significant predictor of worse neurodevelopmental outcome at 1 and 2 years old (P = .05 and P = .02, respectively). Hearing loss requiring amplification has been diagnosed in 44% of the group (control vs TO, 44% vs 43%; P = 1.0).

Conclusions

In this group of infants with severe CDH, there were no differences in outcome at 2 years old despite significant prematurity in the TO group. Oxygen supplementation at hospital discharge identified the most vulnerable group with respect to neurodevelopmental outcome, but all infants had significant growth failure, and hearing impairment is a substantial problem in this population. Severe CDH carries significant risk of chronic morbidity.  相似文献   
78.
The Gleason grading system is a powerful tool to prognosticate and aid in the treatment of men with prostate cancer. The needle biopsy Gleason score correlates with virtually all other pathological variables, including tumour volume and margin status in radical prostatectomy specimens, serum prostate-specific antigen levels and many molecular markers. The Gleason score assigned to the tumour at radical prostatectomy is the most powerful predictor of progression after radical prostatectomy. However, there are significant deficiencies in the practice of this grading system. Not only are there problems among practising pathologists but also a relative lack of interobserver reproducibility among experts.  相似文献   
79.
BACKGROUND AND OBJECTIVES: Low-level laser therapy (LLLT) is widely used in the treatment of musculoskeletal pain. However, there is controversy over its true efficacy. We aimed to determine the efficacy of LLLT in the treatment of neck pain through systematically reviewing the literature. STUDY DESIGN/MATERIALS AND METHODS: A search of computerized bibliographic databases covering medicine, physiotherapy, allied health, complementary medicine, and biological sciences was undertaken undertaken from date of inception until February 2004 for randomized controlled trials of LLLT for neck pain. A comprehensive list of search terms was applied and explicit inclusion criteria were developed a priori. Twenty studies were identified, five of which met the inclusion criteria. RESULTS: Significant positive effects were reported in four of five trials in which infrared wavelengths (lambda = 780, 810-830, 904, 1,064 nm) were used. Heterogeneity in outcome measures, results reporting, doses, and laser parameters precluded formal meta-analysis. Effect sizes could be calculated for only two of the studies. CONCLUSIONS: This review provides limited evidence from one RCT for the use of infrared laser for the treatment of acute neck pain (n = 71) and chronic neck pain from four RCTs (n = 202). Larger studies are required to confirm the positive findings and determine the most effective laser parameters, sites and modes of application.  相似文献   
80.
The male genitalia are a common site of dermatoses. Patients with penile diseases often delay or avoid medical care due to anxiety and embarrassment. In this narrative review, we describe some of the main benign dermatoses localized to male genital, focusing on their epidemiology, clinical and dermoscopic features, as well as available therapies.  相似文献   
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