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61.
Nitric oxide (NO) is a freely diffusible gaseous neurotransmitter generated by a selected population of neurons and acts as a paracrine molecule in the nervous system. NO is synthesized from l ‐arginine by means of the neuronal nitric oxide synthase (nNOS), an enzyme requiring nicotine adenine dinucleotide phosphate (NADPH) as cofactor. In this study, we used histochemical and immunohistochemical techniques to investigate the distribution of NADPH‐diaphorase (NADPH‐d) and nNOS in the spinal cord of the bottlenose dolphin (Tursiops truncatus). Cells with a fusiform‐shaped somata were numerous in the laminae I and II. The intermediolateral horn showed darkly‐stained cells with a multipolar morphology. Neurons with a multipolar or fusiform morphology were observed in the ventral horn. Multipolar and fusiform neurons were the most common cell types in lamina X. Nitrergic fibers were numerous especially in the dorsal and intermediolateral horns. The presence of nitrergic cells and fibers in different laminae of the spinal cord suggests that NO may be involved in spinal sensory and visceral circuitries, and potentially contribute to the regulation of the complex retia mirabilia. Anat Rec, 296:1603–1614, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
62.
Abstract – An increasing prevalence of traumatic dental injury (TDI) has been reported in the last few decades. The aim of this study was to assess the prevalence and severity of TDI and its association with socio‐demographics and physical characteristics in the anterior permanent teeth of 12‐year‐old Brazilian schoolchildren. A cross‐sectional study was carried out in a population‐based sample of 1528 subjects attending 33 public and nine private schools (response rate of 83.17%). A single calibrated examiner performed the clinical examinations at the schools and recorded the TDI index (Children’s Dental Health Survey criteria), overjet and lip coverage. Height and weight were measured to calculate the body mass index (BMI). Parents/legal guardians answered a questionnaire containing socio‐demographic questions. The relationships among TDI, socio‐demographic variables and physical characteristics were assessed by survey Poisson regression models. The prevalence of TDI was 34.79% (mild trauma = 24.37%; severe trauma = 10.43%). Male schoolchildren (RR = 1.41, 95% CI = 1.23–1.61, P = 0.002) and schoolchildren from low socioeconomic status (RR = 1.32, 95% CI = 1.07–1.64, P = 0.021) were more likely to present at least one tooth with TDI, whereas students attending 7th grade (advanced students) were less likely to experience TDI (RR = 0.59, 95% CI = 0.43–0.82, P = 0.012). Regarding the severity analysis, students of mid‐high (RR = 1.46, 95% CI = 1.09–1.94, P = 0.022), mid‐low (RR = 1.68, 95% CI = 1.01–2.77, P = 0.045) and low (RR = 1.78, 95% CI = 1.11–2.85, P = 0.027) socioeconomic status were more likely to have mild trauma when compared with schoolchildren of high socioeconomic status. No significant association between severe trauma and socioeconomic status was observed. In conclusion, this study showed a high prevalence of TDI in 12‐year‐old Brazilian schoolchildren. Socio‐demographic data and school achievement were associated with TDI.  相似文献   
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BackgroundExercise training (ET) has been used as a nonpharmacological strategy for treatment of diabetes and myocardial infarction (MI) separately. We evaluated the effects ET on functional and molecular left ventricular (LV) parameters as well as on autonomic function and mortality in diabetics after MI.Methods and ResultsMale Wistar rats were divided into control (C), sedentary-diabetic infarcted (SDI), and trained-diabetic infarcted (TDI) groups. MI was induced after 15 days of streptozotocin-diabetes induction. Seven days after MI, the trained group underwent ET protocol (90 days, 50-70% maximal oxygen consumption-VO2max). LV function was evaluated noninvasively and invasively; baroreflex sensitivity, pulse interval variability, cardiac output, tissue blood flows, VEGF mRNA and protein, HIF1-α mRNA, and Ca2+ handling proteins were measured. MI area was reduced in TDI (21 ± 4%) compared with SDI (38 ± 4%). ET induced improvement in cardiac function, hemodynamics, and tissue blood flows. These changes were probable consequences of a better expression of Ca2+ handling proteins, increased VEGF mRNA and protein expression as well as improvement in autonomic function, that resulted in reduction of mortality in TDI (33%) compared with SDI (68%) animals.ConclusionsET reduced cardiac and peripheral dysfunction and preserved autonomic control in diabetic infarcted rats. Consequently, these changes resulted in improved VO2max and survival after MI.  相似文献   
65.
BackgroundPercutaneous endoscopic gastrostomy is the preferred way to achieve an artificial feeding route for patients requiring long-term enteral nutrition. Although the procedure is well-standardized, it carries early and late complications.AimTo establish the mortality and morbidity of this technique in a large cohort of children.MethodsA multi-centre prospective clinical data collection from children undergoing percutaneous endoscopic gastrostomy tube implantation has been conducted from January 2004 to December 2007. Previous abdominal surgery was the only exclusion criterion. Follow-up visits were carried out at 1, 3, 6, 12, and 24 months after the procedure.Results239 children (males, 55.2%; mean age 6.05 ± 6.1 years) were enrolled from nine tertiary Italian centres. Major complications occurred in 8 patients (3.3%). The cumulative incidence of complications was 47.7% at 24 months. The presence of thoraco-abdominal deformity was an independent predictor of complications at 12 months. No risk factors were identified in association to complications during the 1st tube replacement.ConclusionIn children undergoing percutaneous endoscopic gastrostomy placement minor complications are common, while severe morbidities are rare. Accurate follow up is essential to recognize every complication, in particular when risk factors such as thoraco-abdominal deformity exist.  相似文献   
66.
Chronic hepatitis B is prevalent in the transplant setting and may cause significant complications. Effective control of viral replication is needed. Besides lamivudine, very little data are available on safety and efficacy of other drugs. We describe our experience with adefovir dipivoxil (ADV) in eight heart transplant recipients. Studies included a baseline liver biopsy, thrice‐monthly clinical, biochemical, and virological evaluations, including genotyping and viral load, polymerase gene sequencing for resistance mutations, liver and kidney function tests, and liver ultrasound. Of eight patients, six had fibrosis score ≤2 and negative HBeAg and seven had hepatitis B virus (HBV) genotype D. Upon ADV start, median HBV‐DNA was 5.8 logs IU/mL and alanine aminotransferase (ALT) levels were mostly normal. All patients had prior mild‐to‐moderate renal functional impairment. Seven of eight patients started ADV after a previous course of lamivudine. Five of these seven patients became HBV‐DNA undetectable within eight months. One patient with low baseline viremia started ADV de novo and suppressed HBV‐DNA. Median treatment duration was 66 months. ADV daily dose was halved in one patient due to renal function worsening. No ALT flares, hypophosphatemia, liver decompensation, liver cancer, or emergence of resistance was observed. Our data suggest that ADV may be a safe and effective rescue treatment for heart transplant recipients with lamivudine‐resistant chronic hepatitis B.  相似文献   
67.
68.
A 61‐year‐old patient was affected by flaccid paraplegia for 20 years because of post‐traumatic medullar injury caused by an accidental fall, with stage IV sacral pressure ulcer for 3 years. The patient later developed stage IV sacral pressure ulcer. After 6 months, a new granulation tissue formation appeared in the wound and a reduction of its diameter was observed (length 20 cm, width 15 cm, depth 5 cm). We therefore treated the wound with PRP (platelet rich plasma) intra‐lesion and peri‐lesional injections. The wounds were covered with three‐dimensional polymerised hyaluronic acid medicated biologic dressing. After the surgery, a moderate reduction in diameter and the depth was observed. Super‐oxidised solution (SOS‐Dermacyn) was applied to control infection locally together with negative pressure to control the exudate and the local bacteremia, to avoid infectious complications without application of systematic antibiotic therapy.  相似文献   
69.

Introduction

Previous studies showed gender-associated clinical and MRI differences in multiple sclerosis (MS) evolution. However, only few studies were done with non conventional MRI techniques and no one was done in a South American MS population. The aim of this study was to investigate gender differences according to nonconventional MRI measures in patients with MS from Buenos Aires, Argentina.

Methods

Relapsing-remitting MS patients (RRMS) with at least 6 years of follow up and an MRI at onset and at 6 years were included. Patients were assessed using nonconventional MRI measures: total brain volume (TBV), neocortical grey brain volume (GBV), white brain volume (WBV), lesion load (LL), % of brain volume change between onset and year 6 (% BVC) and regional brain volume change. Gender-related MRI differences were investigated using general linear model analysis.

Results

The 45 patients were included (25 female). Mean follow up time was 7.3±0.2 years. No differences in age, EDSS at onset, DMD treatment, TBV, GBV, WBV neither LL were found between gender at baseline. Six years later, males showed a decrease in TBV (P=.002) and GBV (P≤0.001) and an increase in LL (P=.02) and % BVC (P<.001) vs. females. Female patients showed a decrease in the volume of frontal subcortical region.

Discussion

This is the first study showing differences in brain volume changes between gender in MS patients from South America. Future studies will confirm our initial findings.  相似文献   
70.
Early maternal exposure to a high-fat diet (HFD) may influence the brain development of rat offspring and consequently affect physiology and behavior. Thus, in the present study, we investigated the somatic, physical, sensory-motor and neurobehavioral development of the offspring of dams fed an HFD (52% calories from fat, mainly saturated) and the offspring of dams fed a control diet (CD – 14.7% fat) during lactation from the 1st to the 21st postnatal day (P). Maternal body weights were evaluated during lactation. In the progeny, somatic (body weight, head and lengths axes) and physical (ear unfolding, auditory conduit opening, eruption of the incisors and eye opening) development and the consolidation of reflex responses (palm grasp, righting, vibrissa placing, cliff avoidance, negative geotaxis, auditory startle response and free-fall righting) were determined during suckling. Depressive and aggressive behaviors were tested with the forced swimming test (FST) and the “foot-shock” test on days 60 and 110, respectively. The open field test was used to assess motor function. Compared to controls, the HFD-pups exhibited decreases in body weight (P7–P21) and body length (P4–P18), but by days P71 and P95, these pups were overweight. All indicators of physical maturation and the consolidation of the following reflexes, vibrissa placing, auditory startle responses, free-fall righting and negative geotaxis, were delayed in HFD-progeny. In addition, the pups from HFD dam rats also exhibited reduced swimming and climbing times in the FST and increased aggressive behavior. No changes in locomotion were observed. These findings show developmental and neurobehavioral changes in the rat offspring of dams fed the HFD during lactation and suggest possible disruption of physical and sensory-motor maturation and increased susceptibility to depressive and aggressive-like behavior.  相似文献   
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