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71.
Protrusion of the zygoma is commonly considered undesirable and unattractive among East-Asians, and many try to achieve a harmonious oval midface by having various cosmetic operations. However, effective contouring for a severe protruding zygoma has rarely been reported .The objectives of this study therefore were to investigate the feasibility and effectiveness of a horizontal V-shaped ostectomy for correction of protrusion of the zygoma and zygomatic arch, and to discuss its indications. From January 2008 to December 2011 we treated 27 patients by contouring of the zygoma with a horizontal V-shaped ostectomy through intraoral and preauricular incisions. The effectiveness was then evaluated with cephalometric radiographs, 3-dimensional computed tomography, and standard facial photographs taken before and after operation. The postoperative appearance of all 27 patients showed that the protrusion had been effectively reduced with no serious complications, and the facial contour had improved. The ?nal aesthetic outcomes were satisfactory for both surgeons and patients. The horizontal V-shaped osteotomy is a good technique for the reduction of protrusion of the zygoma and zygomatic arch, and it has the advantages of more convenient multishifting, better results, and fewer complications. It also ensures the integrity of the structure of the malar complex.  相似文献   
72.
目的:探讨经济有效的治疗放射性颌骨坏死(RONJ)的手术方式。方法77例RONJ根据颌骨坏死的范围、软组织条件选择不同治疗方式。方案1:骨坏死范围局限,牙龈及周围软组织无明显炎症的采用局部刮治或方块切除术;方案2:骨坏死范围较大、周围软组织炎症明显和(或)伴有明显纤维化的病例在控制炎症后,扩大切除同时行血管化游离复合组织瓣修复。结果21例采用方案1,其中15例一期愈合、6例行二次刮治或方块切除;56例采用方案2,其中软组织条件较好的30例,22例一期愈合,5例延期愈合,3例发生骨组织瓣血管危象,经探查和再吻合后1例正常愈合,2例仍发生组织瓣坏死;软组织炎症明显或伴有局部组织明显纤维化26例中,7例出现骨组织瓣血管危象,探查和再吻合后5例正常,2例出现骨坏死,9例一期愈合,15例局部出现不同程度软组织感染坏死,延期愈合。结论局限性放射性颌骨坏死可采用刮治或方块切除;骨坏死范围较大、软组织条件较好的采用血管化游离组织瓣进行修复;软组织纤维化明显的失败率较高,临床使用时应综合多方因素考虑。  相似文献   
73.
74.
Microsomal prostaglandin E synthase-1 (mPGES-1) in myeloid and vascular cells differentially regulates the response to vascular injury, reflecting distinct effects of mPGES-1–derived PGE2 in these cell types on discrete cellular components of the vasculature. The cell selective roles of mPGES-1 in atherogenesis are unknown. Mice lacking mPGES-1 conditionally in myeloid cells (Mac-mPGES-1-KOs), vascular smooth muscle cells (VSMC-mPGES-1-KOs), or endothelial cells (EC-mPGES-1-KOs) were crossed into hyperlipidemic low-density lipoprotein receptor-deficient animals. En face aortic lesion analysis revealed markedly reduced atherogenesis in Mac-mPGES-1-KOs, which was concomitant with a reduction in oxidative stress, reflective of reduced macrophage infiltration, less lesional expression of inducible nitric oxide synthase (iNOS), and lower aortic expression of NADPH oxidases and proinflammatory cytokines. Reduced oxidative stress was reflected systemically by a decline in urinary 8,12-iso-iPF-VI. In contrast to exaggeration of the response to vascular injury, deletion of mPGES-1 in VSMCs, ECs, or both had no detectable phenotypic impact on atherogenesis. Macrophage foam cell formation and cholesterol efflux, together with plasma cholesterol and triglycerides, were unchanged as a function of genotype. In conclusion, myeloid cell mPGES-1 promotes atherogenesis in hyperlipidemic mice, coincident with iNOS-mediated oxidative stress. By contrast, mPGES-1 in vascular cells does not detectably influence atherogenesis in mice. This strengthens the therapeutic rationale for targeting macrophage mPGES-1 in inflammatory cardiovascular diseases.Nonsteroidal anti-inflammatory drugs (NSAIDs) reduce pain and inflammation by suppressing the formation of proinflammatory prostaglandins (PGs), particularly prostaglandin E2 (PGE2) formed by cyclooxygenase-2 (COX-2) (1). However, the development of NSAIDs specific for inhibition of COX-2 revealed a cardiovascular hazard attributable to suppression of cardioprotective PGs, especially prostacyclin (PGI2) (2). This risk appears to extend to some of the older NSAIDs, like diclofenac, that also inhibit specifically COX-2 (3, 4). These developments prompted interest in microsomal PGE synthase (mPGES)-1 as a downstream alternative drug target to COX-2 (5): it is the dominant source among PGES enzymes in the biosynthesis of PGE2 (6). Unlike NSAIDs, inhibitors of mPGES-1 would spare PGI2 from suppression. Indeed, blockade or deletion of mPGES-1 results in accumulation of its PGH2 substrate, rendering it available for metabolism by other PG synthases, including PGI2 synthase (PGIS) (7).Consistent with these observations, we have found that whereas deletion of COX-2 in endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) renders mice susceptible to thrombosis and hypertension (2), deletion of mPGES-1 in vascular cells has no such effect (8). Indeed, global deficiency of mPGES-1 restrains atherogenesis (9), the proliferative response to vascular injury (10) and angiotensin-induced aortic aneurysm formation (11) in mice.Despite this attractive cardiovascular profile, mPGES-1 is a complex drug target. The dominant prostanoid products of substrate rediversion differ among cell types. For example, whereas PGI2 might be augmented in vascular cells, the consequence of mPGES-1 blockade in other cells might be an increase in thromboxane (Tx)A2, a PG that promotes platelet activation, vasoconstriction, and atherogenesis (9). Even if an increase in PGI2 afforded a desirable cardiovascular profile, it might undermine the analgesic efficacy of mPGES-1 inhibitors. Although the impacts of global deletion of mPGES-1 and COX-2 in many mouse models of analgesia are indistinguishable (12, 13), in some, PGI2 rather than PGE2 predominates (14) and thus may be the dominant mediator in certain subtypes of human pain. Finally, the consequences of PGE2 suppression might differ between cell types. PGE2 activates four E prostanoid (EP) receptors with contrasting intracellular signaling and consequent biology (15, 16). Indeed, the contrasting effect of mPGES-1 deletion in myeloid vs. vascular cells on the proliferative response to vascular injury reflects the differential consequences of EP activation rather than substrate rediversion (8).A potentially discriminating feature among inhibitors of COX-2 and mPGES-1 is their effect on atherosclerosis. Global postnatal deletion of COX-2 accelerates atherogenesis in hyperlipidemic mice (17), an observation that accords with a similar effect of deleting the PGI2 receptor (the IP) (18, 19) and with the delayed detection of a cardiovascular hazard in randomized trials of COX-2 inhibitors in patients initially selected for being at low cardiovascular risk (20). By contrast, global deletion of mPGES-1 restrains atherogenesis in mice; in this case suppression of PGE2 coincides with an increase in biosynthesis of PGI2 (9). Here, we wished to segregate the effects on atherosclerosis of mPGES-1 depletion in myeloid from vascular cells. Our results strengthen the rationale for targeting macrophage mPGES-1 in the treatment of inflammatory cardiovascular disease.  相似文献   
75.

Background

Cholecystolithiasis is the most common disease treated by general surgery, with an incidence of about 0.15–0.22 %. The most common therapies are open cholecystectomy (OC) or laparoscopic cholecystectomy (LC). However, with a greater understanding of the function of the cholecyst, more and more patients and surgeons are aware that preserving the functional cholecyst is important for young patients, as well as patients who would not tolerate anesthesia associated with either OC or LC. Based on these considerations, we have introduced a notable, minimally invasive treatment for cholecystolithotomy.

Methods

We performed a retrospective review of patients with cholecystolithiasis who were unable to tolerate surgery or who insisted on preserving the functional cholecyst. Our particular approach can be simply described as ultrasound-guided percutaneous cholecystostomy combined with a choledochoscope for performing a cholecystolithotomy under local anesthesia.

Results

Ten patients with cholecystolithiasis were treated via this approach. All except one patient had their gallbladder stones totally removed under local anesthesia, without the aggressive procedures associated with OC or LC. The maximum number of gallbladder stones removed was 16, and the maximum diameter was 13 mm without lithotripsy. After the minimally invasive surgery, the cholecyst contractile functions of all patients were normal, confirmed via ultrasound after a high-fat diet. Complications such as bile duct injury, biliary fistula, and bleeding occurred significantly less often than with OC and LC. The recurrence rates for each of 2 post-operative years were about 11.11 % (1/9, excluding a failure case) with uncertainty surrounding recurrence or residue, and 22.22 % (2/9, including one non-recurrence patient with follow-up time of 22 months), respectively.

Conclusions

Ultrasound-guided percutaneous cholecystostomy combined with choledochoscope is a safe, efficient, and minimally invasive cholecystolithotomy method. We recommend this technique for the management of small stones (less than 15 mm) in high-risk surgical patients.  相似文献   
76.
OBJECTIVE: To evaluate the effects of coordination exercise on postural stability in older individuals by Chinese shadow boxing, Tai Chi Chuan (TCC). DESIGN: Cross-sectional study. SETTING: Research project in a hospital-based biomechanical laboratory. PARTICIPANTS: The TCC group (n = 25) had been practicing TCC regularly for 2 to 35 years. The control group (n = 14) included healthy and active older subjects. INTERVENTION: Static postural stability test: progressively harder sequential tests with 6 combinations of vision (eyes open, eyes closed, sway-referenced) and support (fixed, sway-referenced); and dynamic balance test: 3 tests of weight shifting (left to right, forward-backward, multidirectional) at 3 speeds. MAIN OUTCOME MEASURES: Static and dynamic balance of Sensory Organization Testing (SOT) of the Smart Balance Master System. RESULTS: In static postural control, the results showed no differences between the TCC or control group in the more simple conditions, but in the more complicated SOT (eyes closed with sway surface, sway vision with sway surface), the TCC group had significantly better results than the control group. The TCC group also had significantly better results in the rhythmic forward-backward weight-shifting test. Duration of practice did not seem to affect the stability of elder people. CONCLUSION: The elderly people who regularly practiced TCC showed better postural stability in the more challenged conditions than those who do not (eg, the condition with simultaneous disturbance of vision and proprioception). TCC as a coordination exercise may reduce the risk of a fall through maintaining the ability of posture control.  相似文献   
77.
78.
An epidemic of urinary tract stones was noted among infants in China, 2008. This event was believed to be associated with consumption melamine-contaminated powdered formula. The patients with symptoms and clinical manifests had already been analyzed in our previous studies. In this study, our aim is to investigate the risk factors of melamine-associated acute kidney injury (AKI) and the potential relationship toward children growth in our five years follow-up. A total of 619 infants with melamine-associated urolithiasis were admitted into 20 different hospitals in the Gansu province, China. All clinical data were divided into AKI and control groups according to the occurrence of AKI. Univariate and multivariate analyses were performed with a logistic regression model to assess the independent risk factors of AKI. Logistic regression analysis revealed that the odds ratio (OR) of AKI was 19.62 in the group of infants who consumed Sanlu® milk powdered infant milk formula. A higher prevalence of AKI was observed in infants age of 6–11 months (OR: 9.59, p?p?p?相似文献   
79.
目的:探讨MR诊断颈动脉体瘤(CBT)的价值。材料与方法:4例经手术病理证实的CBT进行MRI和MRA检查。结果:4例CBT MR检查均显示颈总动脉分叉(common cartid artery bifurcation,CCAB)处类圆形或椭圆形肿瘤,包绕颈内、外动脉,T_1WI呈等或略高信号,T_2WI呈高信号;包膜完整。T_1WI、T_2WI均呈低信号。肿瘤中见多发蜿蜓纡曲的肿瘤小血管。MRA均示CCAB角杯状扩大及肿瘤血管丛。结论:MR不仅能直接显示肿瘤部位、形态、大小及颈动脉关系,也能显示肿瘤血管及CCAB角扩大,是CBT诊断与鉴别的理想方法。  相似文献   
80.
目的:探讨局部麻醉下腹股沟疝无张力修补术的临床路径及其应用。方法观察局部麻醉下腹股沟疝无张力修补术临床路径的56例患者住院时间、住院各项费用及并发症情况。结果进入临床路径56例患者中,54例完成临床路径,2例退出,完成率为96.4%;纳入临床路径的患者住院时间明显缩短,各项费用显著降低;有14例患者出现术后近期并发症,无复发。结论局部麻醉下腹股沟疝无张力修补术临床路径操作简单,能明显缩短住院时间、降低住院医疗成本,减轻患者和社会负担,值得推广。  相似文献   
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