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991.
Investigations on emergence of vancomycin-resistant Enterococcus faecium (VREF) which has recently been attracting attention, especially in the Western countries, have been conducted in Japan. A total of 1,239 isolates of E. faecium were collected from 19 institutions during the period of April 1995 and June 1996, in the purpose of evaluating susceptibilities to variety of antimicrobial agents, including RP59500 and vancomycin (VCM), and detecting vancomycin-resistant genes (van genes). Susceptibilities of penicillin-resistant Streptococcus pneumoniae (PRSP) and methicillin-resistant Staphylococcus aureus (MRSA) were also studied. As a result, 2 isolates of E. faecium were found to be moderately resistant to VCM showing MIC of 8 micrograms/ml though the final identification in species level and the detection of van genes by PCR method have not been completed. On the other hand there detected no MRSA nor PRSP showing moderately resistant or resistant to VCM. It was concluded that RP59500 and VCM possessed favorable activity against clinically isolated E. faecium, PRSP and MRSA. Among other species of enterococci, moderately resistant strains to VCM showing MIC of 8 micrograms/ml were detected; 10 isolates of E. gallinarum, 4 of E. casseliflavus and 2 of E. flavescens. In those isolates, vanC1 and vanC2 were detected by PCR, and vanB was also detected in a isolates of E. gallinarum simultaneously.  相似文献   
992.
Multi-facility joint randomized clinical trials for cancer treatment are the most common method of current clinical study. However, the difference in the rate of participation in multi-facility randomized clinical trials may damage the resulting general validity. Therefore, we studied whether the rate of participation in randomized clinical trials is different between university hospitals and other general hospitals using a questionnaire (with anonymity preserved). There were 744 subjects from university hospitals and 339 from general hospitals participating in the study. The results showed that 10.9 percent of those from university hospitals were willing to participate, against 28.1 percent who were not. Of those from general hospitals (public hospitals in this study) 10.6 percent answered that they would participate and 27.4 percent that they would not. Little difference was found in the rate of participation in randomized clinical trials between university hospitals and other general hospitals. The focus is thus on doctors to solve the possible differences between the facilities in further multi-facility joint studies.  相似文献   
993.
994.
Human glioma cells frequently overexpress epidermal growth factor receptor (EGFR). We found that the CrkII proto-oncogene product was associated with the EGFR in human glioma cells in the absence of epidermal growth factor (EGF). EGF stimulation of glioma cells induced the phosphorylation of tyrosine 221 of the CrkII protein, which correlates with its dissociation from the EGFR. By contrast, Shc and Grb2 were inducibly associated with the EGFR in response to EGF stimulation of glioma cells. In A431 cells, epidermoid carcinoma cells which overexpress EGFR, CrkII was tyrosine-phosphorylated and associated with the EGFR in an EGF-dependent manner. Therefore, the dissociation of CrkII from the EGFR upon stimulation with EGF appears to be specific to glioma cells. The Cbl oncogene product was also tyrosine-phosphorylated in U87MG glioma cells upon EGF stimulation. However, unlike in other cell lines, CrkII was not inducibly bound to Cbl in U87MG glioma cells. Thus, EGF-dependent binding of CrkII to phosphotyrosine-containing proteins appears to be suppressed in glioma cells. To evaluate the physiological role of dissociation of CrkII from EGFR, we expressed the CrkII-23 mutant in glioma cells. CrkII-23 mutant, which was isolated as a suppressor gene of the EGF-dependent transformation of NRK cells, binds constitutively to EGFR. We found that expression of CrkII-23 inhibited the anchorage-independent growth of the glioma cells in the presence of EGF. Taken together, these data implicate EGF-dependent dissociation of CrkII from EGFR in the oncogenicity of human glioma cells.  相似文献   
995.
Serum 25-hydroxy-vitamin D (25-OHD) concentrations were measured in 49 patients with hepatobiliary disease in infancy. Low mean values were found in groups of patients with biliary atresia, neonatal hepatitis, choledochal cyst, and chronic intrahepatic cholestatic syndrome. In the group of patients with surgically repaired biliary atresia, the mean value did not differ from normal. Parenteral vitamin D increased 25-OHD in serum in patients with biliary atresia, but did not do so in one patient with neonatal hepatitis. In contrast, oral vitamin D did not increase serum 25-OHD concentrations in patients with biliary atresia. It is concluded that the reduction of serum 25-OHD seen in biliary atresia was largely due to the malabsorption of vitamin D, while in neonatal hepatitis it was due to impairment of 25-hydroxylation of the vitamin.  相似文献   
996.
A 1011/12-year-old boy with chronic ileocolic intussusception associated with ileocecal lymphosarcoma was decribed. The patient had abdominal pain of 3 months' duration, vomiting, and a firm mass with smooth surface in the right lower abdomen. Barium enema showed intussusception at the distal part of the ascending colon, which was irreducible by hydrostatic pressure. Barium by mouth revealed markedly distended small intestines, which were displaced to the left abdomen. The tumor was inoperable, and the boy died.  相似文献   
997.
Since protease-activated receptors (PARs) are distributed throughout the gastrointestinal tract, we investigated the role of PARs in modulation of the motility of the rat oesophageal muscularis mucosae. Thrombin produced contraction of segments of the upper and lower part of the smooth muscle. Trypsin contracted both the muscle preparations only at high concentrations. SFLLR-NH(2) and TFLLR-NH(2) (PAR-1-activating peptides), but not the PAR-1-inactive peptide FSLLR-NH(2), evoked a marked contraction. In contrast, the PAR-2 agonist SLIGRL-NH(2) and the PAR-4 agonist GYPGKF-NH(2) caused no or only a negligible contraction. In oesophageal preparations precontracted with carbachol, thrombin produced a dual action i.e. relaxation followed by contraction. TFLLR-NH(2) further contracted the precontracted preparations with no preceding relaxation. GYPGKF-NH(2), but not the inactive peptide GAPGKF-NH(2), produced marked relaxation. Trypsin or SLIGRL-NH(2) caused no relaxation. The PAR-1-mediated contraction was completely abolished in Ca(2+)-free medium and considerably attenuated by nifedipine (1 microM) and in a low Na(+) medium. The PAR-4-mediated relaxation was resistant to tetrodotoxin (10 microM), apamin (0.1 microM), charybdotoxin (0.1 microM), L-N(G)-nitroarginine methyl ester (100 microM), indomethacin (3 microM), propranolol (5 microM) or adenosine 3', 5'-cyclic monophosphorothioate, 8-bromo, Rp-isomer (30 microM). Thus, thrombin plays a dual role in modulating the motility of the oesophageal muscularis mucosae, producing contraction via PAR-1 and relaxation via PAR-4. The PAR-1-mediated effect appears to occur largely through increased Na(+) permeability followed by activation of L-type Ca(2+) channels and subsequent influx of extracellular Ca(2+). Our data could provide evidence for a novel role of PAR-4 as opposed to PAR-1, although the underlying mechanisms are still open to question.  相似文献   
998.
We previously reported that the reported that the ratio of gastric ulcer to duodenal ulcer in Hokkadio was higher than that in other area of Japan. This time, we analysed peptic ulcer cases of five hospitals in Hokkaido on the point of geographical and pathological distribution. When we divided these hospitals into two groups (in Sapporo city and other provincial areas) and calculated the sex and age adjusted ratio of gastric ulcer to duodenal ulcer in each group, we found the difference between the two groups (in Sapporo city: 2.26, other provincial area: 5.86) and thought the feature of high ratio the feature of the provincial hospitals. This difference in Hokkaido may be due to the environmental factors for peptic ulcer or the biased sampling of the study. The further study is needed to reveal the geographical and pathological distribution of this disease.  相似文献   
999.
OBJECTIVES: For coronary bypass surgery, radial arteries are often used as bypass grafts. Some of these arteries however, have arteriosclerotic lesions. We attempted to evaluate the relationship between arteriosclerosis and vasodilation. METHODS: Prior to bypass surgery, 20 patients underwent ultrasound vasography to determine the condition of their radial and brachial arteries. Flow-mediated dilation, which is the same as endothelium-dependent vasodilation, was measured in the brachial artery of the nondominant arm by reactive hyperemia after 5-minute forearm ischemia. Vasodilation after application of a sublingual glyceryl trinitrate spray was also measured. RESULTS: During surgery, 4 of 20 radial arteries demonstrated calcification, and 3 of the 4 could be used by removing the calcified part. However, the other artery, which had extensive calcification that could not be detected by ultrasound vasography, was discarded. The amount of vasodilation seen after the administration of sublingual glyceryl trinitrate had no correlation with calcified grafts. Calcified radial arteries demonstrated significantly poor brachial artery vasodilation by an endothelial-dependent vasodilation test. CONCLUSIONS: Calcification in radial arteries can thus only be evaluated by flow-mediated dilation.  相似文献   
1000.
Bilateral transient radial nerve palsies in an infant after cardiac surgery   总被引:2,自引:0,他引:2  
PURPOSE: To describe the case of an infant who suffered bilateral transient radial nerve palsies after cardiac surgery. CLINICAL FEATURES: A one-month-old baby was found to have bilateral wrist and finger drop after the removal of splints that has been applied to the right hand for 14 days and to the right hand for six days during perioperative management of Blalock-Taussig shunt surgery. The hand splints had been applied to the forearms with adhesive silky tape to keep peripheral vascular lines in place. The patient also suffered from several episodes of cardiogenic shock, hypoxemia and generalized edema relating to cardiac dysfunction during this fine period. Given the findings of no impairment of median or ulnar nerves and brachioradial muscle, it was suspected that bandaging with adhesive tapes caused peripheral radial nerve damage at the level of posterior interosseus nerve on forearm. Diminished oxygen delivery and edema may additionally have contributed to peripheral nerve ischemia. The aforementioned neurologic symptoms resolved spontaneously after several days. CONCLUSION: Prolonged compression by bandaging of splints on forearm may have resulted in ischemic damage to the posterior interosseus nerve branch combined with extensor carpi radialis longus nerve branch of the radial nerve. We should attempt to reduce the frequency and duration of splinting of the extremities, especially in sedated, paralyzed babies, given the potential risk of compression neuropathy.  相似文献   
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