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51.
Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.   相似文献   
52.
The [18F]-JNJ-64326067-AAA ([18F]-JNJ-067) tau tracer was evaluated in healthy older controls (HCs), mild cognitive impairment (MCI), Alzheimer’s disease (AD), and progressive supranuclear palsy (PSP) participants. Seventeen subjects (4 HCs, 5 MCIs, 5 ADs, and 3 PSPs) received a [11C]-PIB amyloid PET scan, and a tau [18F]-JNJ-067 PET scan 0-90 minutes post-injection. Only MCIs and ADs were amyloid positive. The simplified reference tissue model, Logan graphical analysis distribution volume ratio, and SUVR were evaluated for quantification. The [18F]-JNJ-067 tau signal relative to the reference region continued to increase to 90 min, indicating the tracer had not reached steady state. There was no significant difference in any bilateral ROIs for MCIs or PSPs relative to HCs; AD participants showed elevated tracer relative to controls in most cortical ROIs (P < 0.05). Only AD participants showed elevated retention in the entorhinal cortex. There was off-target signal in the putamen, pallidum, thalamus, midbrain, superior cerebellar gray, and white matter. [18F]-JNJ-067 significantly correlated (p < 0.05) with Mini-Mental State Exam in entorhinal cortex and temporal meta regions. There is clear binding of [18F]-JNJ-067 in AD participants. Lack of binding in HCs, MCIs and PSPs suggests [18F]-JNJ-067 may not bind to low levels of AD-related tau or 4 R tau.  相似文献   
53.
3-Hydroxypropyl flufenamide (Flu-HPA) is one of a series of flufenamic acid derivatives that enhances blood clot lysis in vitro. Studies of possible mechanisms of action of Flu-HPA were undertaken. The profibrinolytic activity of Flu-HPA in clot lysis assays was found to be dependent on plasminogen. The influence of Flu-HPA on the ability of purified alpha 2-antiplasmin to inhibit purified plasmin was studied. Plasmin activity was determined using 125I-fibrin plates or the spectrophotometric tripeptide substrate, Val-Leu-Lys-paranitroanilide. At Flu-HPA concentrations greater than 1 mM, the inhibitory activity of alpha 2-antiplasmin was abolished in a time-dependent and concentration- dependent manner. The influence of Flu-HPA on the ability of purified Cl inhibitor to inhibit purified plasma kallikrein and beta-Factor XIIa was also studied. Cl inhibitor activity was abolished by Flu-HPA at concentrations greater than 2 mM. Notably, Flu-HPA up to 60 mM did not affect the amidolytic activities of plasmin, kallikrein, or beta-Factor XIIa. Flu-HPA did not release enzyme activity from preformed complexes of either alpha 2-antiplasmin and plasmin of Cl inhibitor and kallikrein. A water-soluble derivative of flufenamic acid, N-flufenamyl- glutamic acid, also inactivated alpha 2-antiplasm and Cl inhibitor. This inactivation was shown to be reversible. These results indicate that synthetic fibrinolytic compounds such as flufenamic acid derivatives may promote fibrinolysis by directly inactivating alpha 2- antiplasmin and Cl inhibitor.  相似文献   
54.
Objective.?There is conflicting data in the literature regarding the risk of obstetric anal sphincter laceration in patients with a prior laceration. This retrospective chart review seeks to examine the risk of recurrence of obstetric anal sphincter lacerations.

Methods.?Patients who sustained anal sphincter laceration at delivery during a 13-year time period from January 1991 to December 2003 were identified from the medical records database at Temple University Hospital. All subsequent deliveries in this group of patients were extracted from the database. Chart review was performed on all subsequent deliveries with specific attention to demographic factors such as age, race, parity, etc., maternal weight, fetal weight, presence of maternal diabetes, and labor characteristics such as induction or augmentation of labor, instrumentation at delivery (vacuum or forceps), use of episiotomy, and degree of perineal laceration.

Results.?There were 23 451 vaginal deliveries at Temple University Hospital between January 1, 1991 and December 31, 2003. Anal sphincter laceration was noted in 778 subjects. Subsequent deliveries among the group of patients with prior sphincter tears numbered 271. Six (2.4%) patients had recurrence of anal sphincter lacerations, and five of them were third degree lacerations. The rate of recurrent lacerations was not significantly different from the rate of initial lacerations (2.4% vs. 3.3%; odds ratio 0.72, 95% confidence interval 0.33–1.59; p = 0.4). Women who sustained recurrent lacerations were older, more obese (mean weight 92 kg vs. 82 kg), had larger babies (3506 g vs. 3227 g), and were more likely to have episiotomies (66.7% vs. 7%) or instrumental deliveries (33.3 vs. 6.5%).

Conclusion.?Prior anal sphincter laceration does not result in an increased rate of recurrence. Operative vaginal delivery particularly with episiotomy is a risk factor for both initial and recurrent laceration.  相似文献   
55.
56.
Septo-optic dysplasia: MR imaging   总被引:5,自引:0,他引:5  
Barkovich  AJ; Fram  EK; Norman  D 《Radiology》1989,171(1):189-192
Septo-optic dysplasia is the diagnosis when optic nerve hypoplasia is seen in conjunction with dysgenesis of the septum pellucidum. Nearly two-thirds of these patients have hypothalamic-pituitary dysfunction, and half have schizencephaly. The disorder is difficult to classify because of the diversity of clinical and pathologic manifestations. Magnetic resonance images of 11 patients with clinical and radiographic evidence of septo-optic dysplasia were reviewed retrospectively. The "syndrome" appears to include two subsets of patients whose abnormalities have different embryogenesis and neuropathologic findings. The existence of these two subsets helps to explain the diversity of the clinical and radiologic findings.  相似文献   
57.
Magnetic resonance (MR) images of the brain in 285 patients between the ages of 2 and 25 years were retrospectively studied to determine the appearance of brain iron accumulation. The globus pallidus, red nucleus, substantia nigra, and dentate nucleus were evaluated with long TR/TE (repetition time/echo time) spin-echo sequences and staged. All four regions in most patients were initially hyperintense compared with white matter (stage I) before becoming isointense (stage II) and subsequently hypointense (stage III). The globus pallidus was the first to reach stage III, the red nucleus and substantia nigra were next, and the dentate nucleus was last. In general, decreased signal intensity (stage III) was not seen in these regions in patients less than 10 years old; in most patients it was seen by age 25 years. The dentate nucleus decreased in signal intensity more slowly and inconsistently; only one-third of patients had reached stage III by age 25 years. The temporal sequence of normal iron deposition as detected with MR imaging is helpful not only in the diagnosis of known iron-deposition diseases but also in the detection of iron-related pathologic changes.  相似文献   
58.
Wilson  AJ; Totty  WG; Murphy  WA; Hardy  DC 《Radiology》1989,173(2):329-333
One hundred two computed tomographic (CT) arthrograms of the shoulder were retrospectively reviewed and compared with conventional double-contrast arthrograms from 101 patients (24 females and 77 males aged 9-70 years). One- to 4-year follow-up was obtained in 84 patients, 40 of whom underwent open-shoulder surgery or arthroscopy. Morphology of the normal portions of each labrum was categorized according to length, width, and tip shape. Correlation between morphology and age was weak, but abnormal labra were more common in younger patients. Conventional radiography was more accurate for detecting bony glenoid margin fractures, but CT was more accurate for detecting Hill-Sach fractures. CT was also more reliable than conventional arthrography in the detection of rotator cuff tears. Hence, few if any conventional radiographs are necessary between contrast material injection and CT imaging. A reduction in the number of images obtained will result in decreased radiation dose, less cost, and shorter examination time without loss of diagnostic accuracy.  相似文献   
59.
Aims. Small encephaloceles of the anterior temporal pole have been increasingly recognised as an underlying epileptogenic substrate in patients with medically refractory epilepsy. The current report aims to expand on the current knowledge by emphasising that seizure semiology in such patients can vary significantly. Methods. Patients were selected from an epilepsy surgery database between 2012 and 2017. Results. Of the 143 patients who underwent epilepsy surgery, six patients had a temporal encephalocele. Four of these patients had stereo-EEG implantation. Of the four patients studied, each had a seizure semiology discordant with an ictal focus in the temporal lobe. Intracranial EEG assessment demonstrated, irrespective of this semiology, seizures originated from the anterior temporal pole. Seizures were observed to rapidly propagate to the orbitofrontal cortex, insula, temporo-occipital junction, and posterior language regions. Engagement of the mesial temporal structures could occur early or late, however, a good surgical outcome was achieved following a focused lesionectomy in either situation. Conclusion. The major finding was that seizures arising from anterior temporal encephaloceles can have an extra-temporal semiology. The varied clinical semiology and the rapid propagation to seemingly distant cortical regions could be explained by the connectivity of the anterior temporal lobe.  相似文献   
60.
机械负荷调节猪腰椎间盘细胞表达α5β1整合素的体外研究   总被引:1,自引:0,他引:1  
目的研究α5β1整合素在体外培养的猪腰椎间盘细胞中的表达和机械负荷对其的影响。方法取10只年龄5-6周、体重25-30kg的猪,处死后12h内,无菌条件下切取完整的腰椎,剔除腰椎周围的韧带和软组织,尤其是椎间盘周围的韧带。从腹侧一次性切开椎间盘取出髓核(nucleus pulpous,NP),仔细分离纤维环(anulus fibrous,AF),将两者立即置于Hanks平衡盐溶液中,制成细胞悬液。分别对腰椎间盘的AF和NP细胞施加1MPa、1Hz,3h/d,共3d的周期性液压,通过对细胞的形态学观察、Western免疫印迹和免疫组织化学染色,检测α5β1整合素在正常腰椎间盘AF细胞和NP细胞中的表达及周期性压力对其的影响。结果经周期性液压后,NP细胞的存活率大于90%,AF细胞的存活率大于85%,加压后的AF细胞和NP细胞均可见体积缩小。α5β1整合素在正常腰椎间盘AF细胞和NP细胞中的表达呈强阳性。Western免疫印迹结果显示:加压后α5β1整合素在AF细胞中的表达均明显减少,P值分别为0.000、0.003,与对照组比较差异有统计学意义;α5β1整合素在NP细胞中的表达也明显减少,P值分别为0.001、0.015,与对照组比较差异有统计学意义。结论机械负荷可引起腰椎间盘细胞中α5β1整合素的变化,提示α5β1整合素在腰椎间盘细胞中可能发挥力学传感器的作用。  相似文献   
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