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991.
Aberrations of chromosomes 3 and 17 were studied by FISH using centromere-specific DNA probes in 11 salivary adenoid cystic carcinomas (ACC) and 8 salivary pleomorphic adenomas (PA), with 3 lymph nodes as controls. Two hybridized signals were detected in 92.8±2.7% of controls, 73.2±7.0% of PA and 66.8±7.9% of ACC cells for chromosome 3, and in 90.4±2.3% of controls, 59.5±25.0% of PA and 44.8±20.2% of ACC for chromosome 17. More than 3 hybridized signals, which indicate polysomy, were observed in 3.1% of controls, 15.5% of PA and 22.9% of ACC cells for chromosome 3, and in 1.2% of controls, 10.3% of PA and 23.1% of ACC cells for chromosome 17. A single hybridized signal was much more frequent for chromosome 17 than for chromosome 3. These findings suggest that polysomy of both chromosomes occurs during the development of salivary gland tumors, and its frequency is increased in adenoid cystic carcinoma as compared to pleomorphic adenoma. In addition, monosomy of chromosome 17 could possibly be significant in salivary gland tumors.  相似文献   
992.
993.
994.
Markers of hepatitis A and B virus were tested in 88 adult Sudanese subjects in Khartoum, Sudan. The subjects consisted of 25 control hospitalized patients, 21 volunteer blood donors, 23 patients with hepatosplenic schistosomiasis, 13 patients with liver cirrhosis and 6 patients with hepatocellular carcinoma (HCC). Antibody to hepatitis A virus was detected in 96% of the total. Hepatitis B surface antigen (HBsAg) was positive in 4, 24, 22, 31, and 67% of the subject groups, respectively. Antibody against hepatitis B core antigen (HBcAb) of undiluted serum was positive in 60, 57, 65, 77 and 83%, and there was no difference in incidence among the groups. It was positive in 200X diluted serum in 4, 24, 17, 23 and 60%. HBsAg and HBcAb (200X) were detected more often in HCC patients than in the control subjects (p less than 0.01). Hepatitis B virus is an important factor in the etiology of HCC in the Sudan.  相似文献   
995.
A 38-year-old man of recurrent episodes of multiple cerebral infarctions with protein C abnormality was reported. He had six episodes of visual disturbance within a year. The neurological examination revealed bilateral visual loss and impaired visual field except for small central area. However, there were no abnormalities in the deep tendon reflexes and muscle strength of all extremities and cerebellar examinations. CT scan revealed multiple low density areas in the bilateral posterior lobes, and cerebral angiography demonstrated the severe stenosis of the ganglionic portion and the supraclinoid portion of the right internal carotid artery. Plasma levels of antithrombin-III activity, plasminogen activity, protein C activity, protein C antigen and protein S antigen were 105, 106, 28, 166 and 120%, respectively. Because only protein C activity decreased markedly, a diagnosis of protein C abnormality was established. We started warfarin therapy under the administration of concentrates of factor IX complex, since then there has been no cerebral accident.  相似文献   
996.
The ventilatory response to isocapnic progressive hypoxia and hyperoxic progressive hypercapnia in 24 diabetic patients were compared with those of sex and age matched normal control subjects. The heart rate response to hypoxia was also measured in both groups. In diabetic patients the ventilatory and heart rate responses to hypoxia were significantly lower than those in the control group (0.10 v 0.24 l/min/% fall/m2 and 0.5 l v 1.27 beats/min/% fall respectively). The ventilatory response to hypercapnia was significantly higher (1.09 v 0.76 l/min/mm Hg/m2) in the diabetic patients. There was a significant correlation between the hypoxic ventilatory response and the heart rate response in diabetic patients (r = 0.56), but not in the control group (r = 0.28). In addition, both the ventilatory and the heart rate responses to hypoxia in diabetic patients had weak but significant correlations with the heart rate variation during deep breathing. It is concluded that the ventilatory and heart rate responses to hypoxia in diabetic patients are impaired, whereas the ventilatory response to hypercapnia is well preserved.  相似文献   
997.
Hepatic Encephalopathy and Reversible Cortical Blindness   总被引:2,自引:0,他引:2  
We report a case of recurrent hepatic encephalopathy accompanied by transient cortical blindness. The patient with cryptogenic liver cirrhosis had six attacks of hepatic encephalopathy of grades II to III during 1 yr after admission. In the beginning of each episode of encephalopathy, when the patient was conscious, a complete loss of vision occurred, but with a normal pupillary reflex to light. At the same time, the visual evoked potential recorded the second negative wave with a prolonged latency and a diminished amplitude. His sight completely returned, and the electroencephalogram tracing and the visual evoked potential response normalized after treatment for the encephalopathy. The loss of vision was thought to be cortical blindness accompanied by hepatic encephalopathy. Thus, in rare cases of hepatic encephalopathy, the visual cortex may be affected, and cortical blindness may occur before the loss of consciousness.  相似文献   
998.
While gastric mucosa contains prostaglandins and leukotrienes, the roles of these substances in the gastric mucosal protection and damage are not clarified. Using AA-861, a specific 5-lipoxygenase inhibitor, and indomethacin, a cyclooxygenase inhibitor, we investigated the roles of intrinsic prostaglandins and leukotrienes in the gastric circulatory change and the development of gastric lesion induced by ethanol. Rats were fasted for 48 hours and allowed free access to water. After light ether anesthesia, rats were orally given AA-861 (gift from Takeda Chem. Industry; 2.5, 10, 40 or 640 mg/kg), indomethacin (20 mg/kg), and the both or AA-861 (40 mg/kg) and indomethacin (20 mg/kg). Thirty min after the treatment, 2 ml of ethanol (30, 40, 70, 99.5%) was orally administered. Sixty min later, the rats were killed to measure the area of mucosal lesions. The gastric mucosa was damaged by ethanol (greater than or equal to 40%) in a dose-dependent manner. The treatment with AA-861 prohibited the gastric mucosal damage. However, the treatment with indomethacin did not show a significant influence to the mucosal damage. Combined treatment of AA-861 and indomethacin yielded no significant difference from that of single treatment with AA-861 in acute gastric mucosal ulceration. The mucosal blood flow velocity was monitored by laser doppler velocimetry before and after the ethanol administration in the groups treated with vehicle, AA-861 or indomethacin. The blood flow velocity decreased after the administration of 40% ethanol in the group treated with indomethacin, and in a group treated with vehicle.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
999.
The purpose of this study is visual evaluation of the distribution of I-123 iomazenil in the brains of patients with various types of mental disorder and to examine whether chronic administration of a clinical dose of benzodiazepine (BZ) affects the binding of I-123 iomazenil to BZ receptors (BZR). The subjects were 10 patients with mental disorders (3 males and 7 females) with a mean age of 26.8 yrs (range 19–39 yrs). Four of 10 patients were administered BZ for over 3 months and the other six were free of BZ for over one month. The SPECT images were obtained at 5–25 min (early) and 170–190 min (delayed), after the bolus i.v. injection of 167 MBq of I-123 iomazenil, with a triplehead gamma camera. The images were visually evaluated and the washout ratios of each region were calculated. In visual analysis, abnormalities were recognized in 5 patients on the delayed SPECT. The abnormalities were recognized more frequently in the superior frontal lobe. The washout ratio was higher in the BZ (+) patient group than in the BZ (?) patient group. I-123 iomazenil is useful, because the SPECT image with I-123 iomazenil reflects the distribution of BZR on the brain and provides the different information from that obtained with perfusion SPECT, X-ray CT or MRI. The rapid washout of I-123 iomazenil from the brains of BZ (+) patients suggests that chronic administration of a clinical dose of BZ affects the binding of I-123 iomazenil to BZR.  相似文献   
1000.
Although appendicitis is the most common condition requiring emergency surgery, the pathogenesis of this disease is poorly understood. In this study, local immune responses in acute appendicitis were investigated, using an experimental rabbit model, as well as in different grades of appendicitis in humans. Polymorphonuclear leukocyte (PMN) and plasma cell isotypes infiltration was measured in 24 New Zealand-bred white rabbits following experimental obstruction of the appendiceal lumen for periods ranging from 30 minutes to 24 hours. Significant infiltration of PMNs, IgM, and IgG plasma cells was noted at 30 minutes following obstruction, and IgA plasma cells were noted at 2 hours after obstruction. The immunopathological features observed in the study of human appendicitis clearly demonstrated the role of plasma cell infiltration in the immunopathogenesis of appendicitis. IgA and IgG plasma cells were significantly increased in the lamina propria of both focal and acute suppurative appendicitis, compared with controls (P less than .001). In focal appendicitis, in which the focus of inflammation is confined to only a few serial sections, the increased IgA and IgG plasma cell infiltration was present throughout the entire length of the resected organ. The possibility, as seen in this study, that antigen stimulation of the effector immune system could give rise to appendicitis, provides new insights into the diversity of inflammatory responses contributing to diseases of the intestinal tract. This previously unrecognised concept in the pathogenesis of appendicitis requires further elucidation of the stimulating agent, and in particular the T-cell recognition process.  相似文献   
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