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101.
Inverted ductal papilloma (IDP) is one of the least common benign papillary/cystic neoplasms of the salivary duct system, being characterized histologically by florid hyperplasia of duct-type epithelial cells into a cystic lumen near the orifice with occasional endophytic growth of the surface squamous epithelium along the terminus of the affected excretory duct. Given its rarity, the exact etiology of IDP remains to be defined. We herein present the first evidence of oncogenic HRAS mutation in a case of oral IDP. This finding, together with the frequent and specific BRAF mutations in sialadenoma papilliferum reported in the recent literature, supports an active role of the MAP-kinase cascade in the pathogenesis of benign papillary neoplasms of terminal duct origin.  相似文献   
102.
Purpose  This study was designed to identify colonoscopic stigmata, indicating substantial invasion into the submucosa by T1 colorectal cancer with sessile morphology, including both flat and protruded types. Methods  A total of 111 Tis or T1 colorectal cancers were studied retrospectively. The lesions were divided into two groups: Group A (n = 83), Tis or T1 cancers with <1 mm submucosal invasion; and Group B (n = 28), T1 cancers with a ≥1 mm submucosal invasion. Printed photographs of the lesions were reviewed by five experienced colonoscopists who were blinded to histology. Deep depression, irregular surface, ulceration or erosion, fold convergence, and spontaneous bleeding were independently evaluated. Findings considered present by three or more reviewers were defined as positive. Kappa analysis was used to measure inter/intraobserver variability. Results  Positive rates of four findings but not fold convergence were significantly higher in Group B than in Group A. Irregular surface and spontaneous bleeding were significant independent predictors of ≥1 mm submucosal invasion, with diagnostic accuracies of 85.6 and 76.6 percent, respectively. Kappa analysis demonstrated fair-to-good inter/intraobserver agreement for spontaneous bleeding and fair-to-good intraobserver agreement for irregular surface. Conclusions  Irregular surface and spontaneous bleeding were colonoscopic stigmata, indicating ≥1 mm submucosal invasion in T1 colorectal cancer.  相似文献   
103.
Aoki T  Akinori E  Yogo Y  Sakamaki F  Suzuki Y  Suemasu K 《COPD》2005,2(2):243-252
Sleep-related disordered breathing (SDB) and its influence on desaturation were examined in stable COPD patients with waking SpO2 > 90%. With respiratory inductance plethysmography, thoracic-abdominal respiratory movements for all events with more than 4% desaturation were analyzed in 26 patients. Types of SDB were confirmed by full polysomnography. Irregular breathing induced desaturation, while stable respiration continued during some desaturation events. Three types of altered ventilation were observed: hypoventilation, paradoxical movement and periodic breathing. An unusual type of paradoxical movement, with normal airflow despite progressive desaturation, was observed in REM sleep. Patients were divided into desaturation (15 patients) and non-desaturation (11 patients) groups. Daytime arterial blood gas, lung function values, and 6-min walking distance did not differ. Awake, mode, maximum and minimum nocturnal SpO2 were lower in the desaturation group. SDB-induced desaturation events in the desaturation group were more frequent (9.2+/-3.5 vs. 1.8+/-2.2 times), a greater SpO2 decrease (11.4+/-7.1% vs. 5.2+/-2.1%) and longer duration (73.2+/-34.8 vs. 18.8+/-39.0 min). Patterns of SDB in the desaturation group were hypoventilation (74.4+/-23.4%), paradoxical movement (10.2+/-14.5%), periodic breathing (12.1+/-18.3%) and unclassified (5.8+/-11.2%). These results reveal that lower SpO2 and SDB influence nocturnal desaturation in stable COPD patients.  相似文献   
104.
105.
Even with continuous vector control, dengue is still a growing threat to public health in Southeast Asia. Main causes comprise difficulties in identifying productive breeding sites and inappropriate targeted chemical interventions. In this region, rural families keep live birds in backyards and dengue mosquitoes have been reported in containers in the cages. To focus on this particular breeding site, we examined the capacity of bird fecal matter (BFM) from the spotted dove, to support Aedes albopictus larval growth. The impact of BFM larval uptake on some adult fitness traits influencing vectorial capacity was also investigated. In serial bioassays involving a high and low larval density (HD and LD), BFM and larval standard food (LSF) affected differently larval development. At HD, development was longer in the BFM environment. There were no appreciable mortality differences between the two treatments, which resulted in similar pupation and adult emergence successes. BFM treatment produced a better gender balance. There were comparable levels of blood uptake and egg production in BFM and LSF females at LD; that was not the case for the HD one, which resulted in bigger adults. BFM and LSF females displayed equivalent lifespans; in males, this parameter was shorter in those derived from the BFM/LD treatment. Taken together these results suggest that bird defecations successfully support the development of Ae. albopictus. Due to their cryptic aspects, containers used to supply water to encaged birds may not have been targeted by chemical interventions.  相似文献   
106.
The effect of heel elevation of shoes in Parkinson's disease was analyzed by using two gait measurement systems. The heel elevation brought about some improvement of walking in the patients with Parkinson's disease with shortening of a stride period, a step period and the transition time of the plantar pressure peak from heel contact to toe off. After measurement study of the gait, all the patients answered the best heel height of shoes was higher than that of their casual footwear or the same. This simple treatment method may be also effective for fall prevention in patients with Parkinson's disease, and further investigation with follow-up observations should be necessary to verify the effect.  相似文献   
107.
This study attempts to address an important clinical issue by identifying potential candidates of VEGF signaling through Flt-1 receptor that trigger angiogenic signal under ischemic stress. To determine the significance of VEGF-Flt-1 (VEGFR1) signaling in ischemic preconditioned (PC) myocardium, we used heterozygous Flt-1 knockout (KO) mice to dissect the pathway and identify candidate genes involved in VEGF signaling. DNA microarrays were employed to detect, characterize and distinguish altered myocardial gene expression by comparing between wild type (WT) CD-1 and heterozygous Flt-1 KO mice when exposed to ischemia (30 min) and reperfusion (2 h). Moreover, KO mice demonstrated reduced beneficial effects of PC when compared to the WT with PC. In the KO and WT mice, the % recovery of the left ventricular developed pressure and the maximum first derivative of the developed pressure after ischemia/reperfusion without PC were similar. However, when animals were subjected to PC, the left ventricular functional recovery throughout the reperfusion period was significantly lower in KO mice than in WT mice. These results indicate for the first time that in the heterozygous Flt-1 KO mice, PC is not as effective as that found in WT. This observation may be due to downregulation of several important genes such as growth-regulated oncogene 1 (Gro1), heat shock proteins (HSP), I kappa B kinase beta (IKK beta), colony-stimulating factor-1 (CSF-1) and annexin A7, suggesting the importance of VEGF-Flt-1 receptor signaling during PC.  相似文献   
108.
BACKGROUND/AIMS: We investigated the relationship between percutaneous papillary balloon dilatation (PPBD) and hyperamylasemia after PPBD. METHODOLOGY: We studied the rate of pancreatitis and asymptomatic hyperamylasemia after PPBD for choledocholithiasis in 64 symptomatic patients. Pancreatitis was defined as epigastric pain combined with at least a 3-fold rise in serum amylase at 24 hours after PPBD. Asymptomatic hyperamylasemia was defined as a rise in serum amylase (normal range, 50 to 160 IU/L) without epigastric pain. RESULTS: The stones were successfully pushed out into the duodenum in all patients. Three patients developed post-PPBD pancreatitis, graded moderate in one and mild in two. Serum amylase values were elevated over the normal upper limit in 21 patients, 33%, over 3-fold in 10, 16% over 1000 IU/L in 6, 9%. Asymptomatic hyperamylasemia was observed in 18 patients. The amylase value after PPBD was elevated to more than 160 IU/L in 44% (17/39) of patients 80 years old or under vs. 16% (4/25) of patients older than 80 and in 23% (10/44) of patients with intrahepatic bile duct dilatation on admission vs. 55% (11/20) of patients without it, with a significant difference, respectively (p<0.05). The amylase value after PPBD was elevated to more than 1000 IU/L in 15% (6/39) of patients 80 years old or under vs. 0% (0/25) of patients older than 80 and in 29% (4/14) of patients with bile duct stones having a horizontal diameter of 8mm or smaller and 4% (2/50) of patients with stones larger than 8mm (p < 0.05 and p<0.01, respectively). CONCLUSIONS: We believe that postoperative continuous decompression of the bile duct by PPBD is reliable and that it contributed to the prevention of severe pancreatitis. We conclude that PPBD can be performed more safely in symptomatic patients older than 80 with choledocholithiasis with intrahepatic bile duct dilatation at the time of admission.  相似文献   
109.
A 73-year-old Japanese woman was referred for examination of right flank pain and progressive hypertension. Abdominal CT incidentally detected a right adrenal mass 8 cm in size. The tumor exhibited isodensity by CT and contained high-intense lesion by T2-weighted MRI. Scintigraphy with (131) I-metaiodobenzylguanidine and (131) I-adosterol showed no abnormal uptake by whole body scan. Positron emission tomography scan with (18) F-2-fluoro-D-deoxyglucose demonstrated an exclusive uptake in the right adrenal mass. Adrenocortical hormone levels and catecholamine secretion were within normal range; however, the level of serum neuron-specific enolase (NSE) was found to be markedly high. After controlling systemic blood pressure with an alpha1-blocker, the right adrenal tumor was surgically removed, along with the right kidney and inferior vena cava which adhered to it. The tumor was pathologically proven to be leiomyosarcoma, which was immunohistochemically positive with alpha-smooth muscle actin and negative with CD57, S-100 and c-kit proteins. Notably, NSE protein was massively expressed in the resected tumor. After surgery blood pressure was controlled with regular medication and serum NSE levels have since normalized. The possibility of leiomyosarcoma should be kept in mind in adrenal incidentalomas with rapid growth and atypical radiological images. Our findings suggest that circulating NSE levels may be clinically useful for early detection of recurrence.  相似文献   
110.
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