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981.
Time-domain diffuse correlation spectroscopy (TD-DCS) is an emerging optical technique that enables noninvasive measurement of microvascular blood flow with photon path-length resolution. In TD-DCS, a picosecond pulsed laser with a long coherence length, adequate illumination power, and narrow instrument response function (IRF) is required, and satisfying all these features is challenging. To this purpose, in this study we characterized the performance of three different laser sources for TD-DCS. First, the sources were evaluated based on their emission spectrum and IRF. Then, we compared the signal-to-noise ratio and the sensitivity to velocity changes of scattering particles in a series of phantom measurements. We also compared the results for in vivo measurements, performing an arterial occlusion protocol on the forearm of three adult subjects. Overall, each laser has the potential to be successfully used both for laboratory and clinical applications. However, we found that the effects caused by the IRF are more significant than the effect of a limited temporal coherence.  相似文献   
982.
Objective: To assess the efficacy of surgical excision of sub-Tenon triamcinolone acetonide (TA) deposits in the control of steroid-induced glaucoma.Design: Prospective, nonrandomized, interventional case series.Participants: Eighteen eyes of 14 subjects with increased IOP within 6 months of sub-Tenon TA injection who did not respond to medical antiglaucomatous treatment were included in the study.Methods: Under topical anaesthesia, steroid deposits were completely excised and placed in ethyl alcohol for the determination of the TA amount using high-performance liquid chromatography. The patients were followed up for 6 months and a paired-sample t test was used to compare mean IOP before and after excision of sub-Tenon TA deposits.Results: The mean IOP levels before and after the sub-Tenon steroid injections were 15.9 (SD 2.9) mm Hg and 36.4 (SD 8.4) mm Hg, respectively (p < 0.001). IOP levels decreased significantly after the removal of the deposits (mean 15.3 [SD 2.1] mm Hg) (p < 0.001). Within 6 months of follow-up, all glaucoma medications were stopped in 9 subjects without further IOP increase, whereas IOP control in 5 subjects necessitated using glaucoma medications. The median TA amount was found to be 7.35 mg (range 3.3–29.68 mg). IOP decrease after the excision showed no correlation with the amount of TA (p = 0.8).Conclusions: Surgical excision of the sub-Tenon steroid deposit should be considered as the primary treatment for steroid-induced glaucoma refractory to medical treatment.  相似文献   
983.
The present study was designed to evaluate the usefulness of plasma gastrin determinations as a diagnostic aid and to review the clinical and haematological findings in cattle with bleeding abomasal ulcers. Twenty‐nine cows with bleeding abomasal ulcers and six healthy cows were used. Clinical and laboratory examinations, including plasma gastrin levels, were performed. Anorexia, depression, dark‐coloured to black faeces, pale mucous membranes, abdominal pain, moderate tachycardia and tachypnoea were the most pronounced clinical symptoms in the cattle with bleeding abomasal ulcers. Plasma gastrin concentration was significantly higher (P < 0.05) in the cattle with bleeding abomasal ulcers than in healthy cows. The mean plasma gastrin concentration in healthy cattle was 103.2 pg/ml, while the mean plasma gastrin concentrations in cattle with bleeding abomasal ulcers were found to be 213.6 pg/ml. Haemoglobin levels, packed cell volume, total white blood cell count and mean corpuscular volume were significantly lower (P < 0.05) in the cows with bleeding abomasal ulcer than in the healthy cattle. The results of this study show that measurement of plasma gastrin can be useful in the diagnosis of bleeding abomasal ulcers in cattle.  相似文献   
984.
985.
Severe heart failure represents a major source of morbidity and mortality. Poor right ventricular function is an independent prognostic marker for mortality in patients with chronic heart failure. In this study, levosimendan (L) and dobutamine (D) in patients with severe chronic biventricular failure were compared. Forty consecutive patients, who were judged for inotropic therapy by their primary physicians, with acutely decompensated systolic heart failure and having moderate-to-severe right ventricular dysfunction with right ventricular fractional area change of ≤24%m were randomized to L and D in a 2:1 fashion. Echocardiographic parameters including tricuspid annular motion and clinical issues were considered. Mean age and sex distribution were not different between the two groups. After the infusion, ejection fraction improved and systolic pulmonary artery pressure decreased significantly in both arms. Longitudinal systolic function of tricuspid annulus improved significantly better in patients with L compared to patients with D (15% ± 12% vs. 2% ± 6% improvement, P < 0.001). Furthermore, L improved both 24-h urine output and creatinine, whereas D showed only a small, but significant improvement in urine output without any improvement in the creatinine levels. Levosimendan seems to offer more beneficial effects compared to dobutamine in a specific group of patients with biventricular failure.  相似文献   
986.
Oxidant status increased during fracture healing in rats   总被引:1,自引:0,他引:1  
We evaluated oxidant status during bone healing in 50 rats. In 40 rats, the right tibia was fractured and fixed intramedullarlyy (study leg) and the left tibia was pinned but not fractured (control leg). Rats were killed on days 1, 3, 7, 14, 28 and malondialdehyde (MDA) levels were determined in tibial bone tissue. The MDA levels of study and control legs were compared with basal MDA levels in bone in 10 rats. There was no apparent difference between the basal level and control legs, but the study legs showed a statistically significant increase in MDA levels on days 7 and 14. We conclude that no oxidative stress injury occurs during the ischemic period of fracture healing, but it may be significant during inflammation and the formation of callus.  相似文献   
987.
In this study we report a rare case of a giant midline posterior fossa teratoma; its clinical presentation, radiological appearance, treatment and outcome, with an extensive review of the literature. Received: 7 December 1998 Revised: 22 March 1999  相似文献   
988.
Angiolipomas of the spinal canal are extremely uncommon benign neoplasms composed of mature lipomatous and angiomatous elements. A case of thoracic spinal extradural angiolipoma producing progressive spinal cord compression in a 54-year old housewife is presented and 74 previously reported cases in the world literature over a period spanning nearly one century from 1890 to the present are analysed. The 75 total cases (46 females and 29 males) ranged in age from 6 to 73 years (mean 42.7, SD 15.9; median 43). The angiolipomas were located in the extradural compartment in 72 patients and intradural compartment in 3; 14 of the extradural lesions infiltrated the surrounding bone (infiltrating subgroup). Computed tomography (CT) and magnetic resonance imaging (MRI) revealed the fat-density lesions in all the cases that we studied. The findings indicate that spinal angiolipomas predominantly affect women. Their preponderance in peri- or postmenopausal women, and their fluctuating clinical course during the pregnancy support a role of hormonal influence on the development of the lesion. They often involve the thoracic region, and produce symptoms and signs of spinal compression and, in some cases, bone involvement. MRI is the investigation of choice for the diagnosis of these lesions. Non-infiltrating angiolipomas can usually be removed easily through a laminectomy, but infiltrating angiolipoma can be only partially resected. However, outcome is not worse in the infiltrating than in the non-infiltrating lesions and appears to be relatively independent of the completeness of the surgical removal. Subtotal resection usually provides substantial symptomatic relief, because these lesions are slow growing and do not undergo malignant transformation. The results of this review show that angiolipomas of the spinal canal have a good prognosis after surgical removal, even if infiltrating.  相似文献   
989.
Phase 3 trials Viale-A and Viale-C evaluated health-related quality of life (HRQoL) in patients with AML unfit for intensive chemotherapy who received venetoclax (VEN) + (AZA) (Viale-A) or low-dose cytarabine (LDAC) (Viale-C) or placebo (PBO) + AZA or LDAC. Patient-reported outcomes included: EORTC QLQ-C30 global health status (GHS/QoL) and physical functioning (PF), PROMIS Cancer Fatigue Short Form 7a (Fatigue), and EQ-5D-5L health status visual analog scale (HS-VAS). Time to deterioration (TTD), defined as worsening from baseline in meaningful change thresholds (MCT) of ≥10, 5, or 7 points for GHS/QoL or PF, fatigue, and HS-VAS, respectively, was assessed; differences between groups were analyzed using Kaplan-Meier and unadjusted log-rank analyses. VEN + AZA vs PBO + AZA patients had longer TTD in GHS/QoL (P = 0.066) and fatigue (P = 0.189), and significantly longer TTD in PF (P = 0.028) and HS-VAS (P < 0.001). VEN + LDAC vs PBO + LDAC patients had significantly longer TTD in GHS/QoL (P = 0.011), PF (P = 0.020), and fatigue (P = 0.004), and a trend in HS-VAS (P = 0.057). Approximately 43%, 35%, 32%, and 18% of patients treated with VEN + AZA, AZA + PBO, VEN + LDAC, or LDAC + PBO, respectively, saw improvements >MCT in GHS/QoL. Overall, VEN may positively impact HRQoL in patients with AML ineligible for intensive chemotherapy, leading to longer preservation of functioning and overall health status.Subject terms: Quality of life, Cancer  相似文献   
990.
Hydatid disease, a worldwide zoonosis, is caused by the larval stage of the Echinococcus tapeworm. Although it can involve almost every organ of the body, lung involvement follows in frequency the hepatic infestation in adults and is the predominating site in children. Radiologically, hydatidosis usually demonstrates typical findings, but many patients are at risk of developing various complications of hydatid disease with atypical imaging findings and these are rarely described in the literature. In this pictorial review, the imaging features of local complications of hydatid disease involving the thorax including intrapulmonary or pleural rupture, infection of the ruptured cysts, reactions of the adjacent tissues, thoracic wall invasion and iatrogenic involvement of pleura are described. Additionally, imaging characteristics of transdiaphragmatic thoracic involvement of hepatic hydatid disease are presented. To prevent the development of subsequent catastrophic results, all radiologists need to be aware of the atypical imaging appearances of complications of pulmonary hydatid disease.  相似文献   
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