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21.
Some chordomas have a very poor prognosis because of their aggressive growth nature, but the efficacy of repeat operations for these cases has not been well documented. This report concerns 3 patients with aggressive chordoma of the clivus, who underwent operations 6 to 12 times over a period of 8 to 17 years because of symptomatic regrowth. Overall mean interval between repeat operations was 18 months with a range from 5 to 57 months and survival times were 9 to19 years after the first surgery. Main symptoms before each operation were diplopia and visual disturbance. Repeat palliative operations by intentional extradural debulking of the tumour to decompress offending neural structures, as well as maximal removal of the tumour, using appropriate skull base approaches, can mitigate progressive symptoms, and may result in better quality and some prolongation of life, although our patients gradually deteriorated neurologically throughout the clinical course.  相似文献   
22.
A 67-year-old male diagnosed clinically as having rheumatoid pleuritis and bronchiolitis was treated with adrenocorticosteroid. His clinical findings improved, but following the tapering of the steroid dose, exacerbation occurred. After the steroid dose was increased, serological findings improved, but chest X-ray findings revealed no improvement. To re-evaluate the etiology of the bronchiolar lesion, open lung biopsy was performed. The biopsy specimen showed lymphocytic infiltration and formation of lymphoid follicles in and around the bronchioles. The pulmonary lesion was diagnosed as follicular bronchiolitis.  相似文献   
23.
Two siblings with ileal atresia are described; one boy presented with ileal perforation and the other with meconium peritonitis, diagnosed by antenatal ultrasonography. The site and type of atresia, complications and associated anomalies of reported cases among siblings also are discussed.  相似文献   
24.
1. The effects of the cyclic nucleotide phosphodiesterase (PDE) inhibitors, Ro20,1724, 3-isobutyl-1-methylxanthine (IBMX), trifluoperazine (TFP) and amrinone on pancreatic exocrine secretion were investigated in anaesthetized dogs in comparison with those of secretin and cholecystokinin octapeptide (CCK-8). 2. Ro20,1724 (1–30 nmol/kg), IBMX (3–30 nmol/kg), secretin (0.01–0.1 pmol/kg) or CCK-8 (0.1–1 pmol/kg) injected i.a. elicited a dose-dependent increase in the secretion of pancreatic juice, but TFP and amrinone (up to 1 μmol/ kg) did not. 3. The bicarbonate concentration in pancreatic juice was increased and the protein concentration was decreased by Ro20,1724, IBMX and secretin. Cholecystokinin octapeptide increased the protein concentration but did not alter the bicarbonate concentration. 4. Ro20,1724 and IBMX elicited more than the respective additive secretory response when added together with secretin, although the stimulatory effects of CCK-8 with Ro20,1724 and IBMX were additive. 5. Ro20,1724 and IBMX increased cyclic AMP concentration but did not affect cyclic GMP concentration. 6. These results suggest that Ro20,1724 and IBMX have secretory properties on pancreatic exocrine glands of the dog, which may be mediated through an increase in cyclic AMP subsequent to inhibition of PDE activity. Furthermore, pancreatic PDE enzymes in the dog may be mainly type IV.  相似文献   
25.
The effects of a synthesized phosphodiesterase inhibitor, ZSY-27, on the secretion of pancreatic juice were investigated in dog isolated and blood-perfused pancreas, and compared with those of secretin and dopamine. Intravenous administration of ZSY-27 (0.3-1 mg/kg) elicited increases in pancreatic secretion. Intra-arterial (i.a.) administration of ZSY-27 (0.1-1 mg) also elicited increased secretion. The secretory activity of ZSY-27 (1 mg) was approximately equal to that of 0.1 units of secretin and 2.5 micrograms of dopamine. The concentration of bicarbonate in the pancreatic juice induced by ZSY-27 i.a. was increased, but the protein concentration was not increased significantly. These effects are analogous to those of secretin and dopamine. ZSY-27-induced pancreatic secretion was not modified by pretreatment with phentolamine, propranolol, atropine, sulpiride and cimetidine. Secretin-induced secretion was significantly potentiated by infusion of ZSY-27 (25 micrograms/min) but dopamine-induced one was not. These results suggest that ZSY-27 increases pancreatic secretion acting directly on the ductular cells of the dog pancreas, at least in part, through the increase of intracellular cyclic AMP concentration by inhibiting phosphodiesterase activity.  相似文献   
26.
We have previously shown that interleukin (IL)-1beta and tumour necrosis factor (TNF)-alpha mRNA levels in rat alveolar macrophages are increased in by endotoxin (lipopolysaccharide; LPS)- stimulation and further enhanced by culturing with low-Mg2+ medium. We have now investigated the mechanisms of underlying this enhancement by using some specific signal transduction inhibitors. The enhanced elevation of both mRNAs levels was suppressed by pretreatment with TMB-8 (which inhibits calcium release from the endoplasmic reticulum) or dexamethasone (which inhibits nuclear factor [NF]-kappaB and activator protein [AP]-1), but not with verapamil or nifedipine (which inhibits calcium channels). The enhancment of IL-1beta, but not TNF-alpha mRNA levels, was suppressed by pretreatment with W-7 (which inhibits calmodulin), whereas the enhancement of TNF-alpha mRNA levels was suppressed by pretreatment with U73122 (which inhibits phospholipase C). Curcumin (an inhibitor of AP-1), suppressed the increases in both mRNAs induced by low-Mg2+ medium alone, but had no suppressive effect on the levels of either mRNA after LPS-stimulation in low-Mg2+ medium. Pyrrolidine dithiocarbamate (an inhibitor of NF-kappaB) prevented the elevation of TNF-alpha mRNA levels induced by low-Mg2+ medium without LPS-stimulation, but had no suppressive effect on IL-1beta mRNA levels. From these results, we conclude that the enhanced elevation of IL-1beta and TNF-alpha mRNA levels seen in LPS-stimulated alveolar macrophages in low-Mg2+ medium occurs partly via the same, and partly via different, signaling pathways.  相似文献   
27.
While nonspecific airway hyperresponsiveness (AHR) is a central feature of allergic bronchial asthma, the mechanism underlying the development of AHR is not clearly understood. We have previously demonstrated in vitro hyperresponsiveness of bronchial smooth muscle to acetylcholine (ACh) in rats that were actively sensitized and repeatedly challenged with aerosolized antigen. It has also been demonstrated that the ACh-induced, RhoA-mediated Ca(2+) sensitization is markedly augmented concomitantly with an increased expression and activation of RhoA protein in the bronchial smooth muscle of the antigen-treated rats. In the present study, we have investigated whether TNF-alpha, a proinflammatory cytokine which is involved in bronchial asthma, causes upregulation of RhoA mRNA and protein in the rat bronchus. Treatment of rat bronchial smooth muscle preparations with TNF-alpha (300 ng/ml for 24 hr) significantly shifted the concentration-response curve to ACh upwards, but did not alter the response to high K(+), when compared to that of control tissues. Levels of RhoA mRNA and protein in the TNF-alpha-treated bronchus were significantly greater than those in the control group. In conclusion, it is suggested that the augmentation of the ACh-induced contractile response evoked by TNF-alpha might be mediated by an upregulation of RhoA in rat bronchial smooth muscle.  相似文献   
28.
We investigated the relationship between esophageal varices and the collaterals by endoscopy and endoscopic ultrasound (20 MHz ultrasonic miniprobe; UMP). Moreover, we investigated the correlation between the collaterals around the esophagus and recurrence of esophageal varices in patients with portal hypertension who had undergone EIS. The collaterals were divided into two groups: peri‐esophageal collateral veins (peri‐ECVs) and para‐esophageal collateral veins (para‐ECVs). These were scored as mild or severe according to the stage of development. According to endoscopy, the varix form was significantly larger in severe the peri‐ECVs group than in mild the peri‐ECVs group. The prevalence of perforating veins increased according to the varix form. With regard to variceal recurrence, in patients with variceal recurrences, UMP findings included a significantly higher incidence of severe peri‐ECVs, a significantly larger diameter of perforating veins compared with patients without recurrence. In conclusion, the presence of severe peri‐ECVs and large perforating veins in the esophageal wall strongly correlates with occurrence and recurrence of esophageal varices in patients with portal hypertension. An understanding of these UMP abnormalities on the basis of hemodynamics around the esophagus is thought to be important for management of esophageal varices in patients with portal hypertension.  相似文献   
29.
Recently, a self‐expandable metallic stent has been recognized for treatment of malignant duodenal stenosis. But the complications by stenting are important problems even now. In the present study, we report our new method of duodenal stenting by using of double‐balloon enteroscopy considered safe and effective.  相似文献   
30.
Elderly onset rheumatoid arthritis (RA) is difficult to diagnose definitively when the patients note their first symptoms of arthritis above the age of 75 years old. In this report, we reviewed the clinical features of elderly onset RA and its diagnosis. The subjects included 4 females, aged 78, 83, 84 and 93 years, respectively. The onsets were abrupt in 2 cases and more slowly arriving in the other 2. Shoulder joints and wrist joints were involved in all cases. Knee joints, finger joints and foot joints were involved in 3 cases and the elbow was involved in one case. Anti-RA treatment quickly attenuated the acute and severe arthritis and brought down the high CRP level associated with vivid inflammatory activity of RA. The RAPA value was very high in all but one of the cases. Severe destructive findings in radiography was undetectable in the major joints (e.g. shoulder, hip and knee joints). Radiographic findings in wrist and finger joints were also very difficult to differentiate from arthrosis and osteoporosis. On the other hand, RA involvement in the cervical spine was certain in the radiographs; 1 case had anterior atlantoaxial subluxation and 2 cases had subaxial intervertebral erosion. Pathological radiographic findings in the cervical spine are useful for the diagnosis of elderly onset RA.  相似文献   
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