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21.
A 68-year-old man noticed weakness in both legs, which worsened rapidly with additional urinary disturbance. At the time of admission, a neurological examination revealed spastic paraplegia. Sensation was intact. Magnetic resonance imaging (MRI) did not show any lesions in the spinal cord. Thereafter, sensory disturbance under Th5 level and weakness in both hands developed gradually. Seven months after the onset, he noticed pain of the right upper arm. MRI showed an epidural mass at the level between the lower cervical and the upper thoracic spine. Histological examination of the epidural mass revealed Ki-1 lymphoma. In this case, the diagnosis was difficult, because lymphoma did not present epidural mass in the early stage. We speculate that spinal epidural lymphoma might disturb venous circulation and cause myelopathy in this patient.  相似文献   
22.
We report herein the case of a 42-year-old man in whom dyspnea on exertion was found to be caused by isolated tricuspid stenosis. Two-dimensional echocardiogram showed thickening of the tricuspid valve with a markedly enlarged right atrium. A color-flow Doppler examination-revealed severe tricuspid stenosis without regurgitation and a Doppler-derived tricuspid diastolic pressure gradient of 23 mmHg. At the time of surgery, the patient was noted to have a stenotic tricuspid valve with thickened leaflets, fused commissures, and almost normal chorda tendineae. The valve leaflets were teased apart to the scattered specimen, and tricuspid valve replacement was successfully performed. Microscopic examination of the specimen demonstrated infective endocarditis. Isolated acquired tricuspid stenosis is extremely rare and, to our knowledge, this is the first case of infective endocarditis being involved as the primary cause.  相似文献   
23.
A 37-year-old man visited our hospital with the chief complaint of a painless mass in subcutaneous tissue of the pubis. We extirpated the localized cyst 2.5 x 4 cm in size. Histological diagnosis was cystic lymphangioma without malignant findings. We reviewed the literature on lymphangioma, a rare disease seldom seen in urological fields.  相似文献   
24.
The radiological characteristics of the lead in five different dental film packets currently on the market in Japan were studied with monochromatic X-rays. Four packets were of a foil type while in the fifth, the lead was incorporated in the vinyl of the film packet. The samples were analysed by polychromatic photon absorptiometry, and the main component found to be lead with tin and/or antimony in smaller amounts. The shielding effect was calculated and, with the exception of the lead vinyl type, all found to exceed the ISO standard 3665. The lead foils attenuated the primary beam by, on average, 77% and 56% at 60 and 90 kVp respectively: in contrast, the reduction with the lead vinyl packet was only 38% and 23%. Using a 7 cm round beam, the lead foils reduced the dose by an average of 15% compared with 30% with a rectangular beam; the average dose reduction with the lead vinyl type was 8% and 15% respectively. These data show that the lead vinyl packet is unsuitable for clinical use and confirm the importance of optimum beam collimation for the reduction of patient risk.  相似文献   
25.
The purpose of this study was to determine the relationship between segmental hyperintensity of the liver on T1-weighted images and segmental cholestasis in patients with obstructive jaundice. T1-weighted and T2-weighted MR images were obtained of 73 patients with obstructive jaundice caused by various diseases. Fat-suppressed T1-weighted images were also obtained of 10 patients. Eleven patients with segmental intra-hepatic bile duct dilatation (cholestasis) showed segmental hyperintensity on T1-weighted images and/or fat-suppressed T1-weighted images and no signal intensity difference on T2-weighted images. Sixty-two patients with widespread intrahepatic bile duct dilatation showed no intensity difference on T1-weighted and T2-weighted images (P < .01). Segmental hyperintensity on T1-weighted images was correlated with intrahepatic cholestasis.  相似文献   
26.
Wilms tumor gene (WT-1) expression has been reported in many human cancers, including most ovarian and peritoneal serous carcinomas, but has not been studied in carcinomas of the fallopian tube. In this study, the authors evaluated the immunohistochemical expression of WT-1 in serous carcinomas of the fallopian tube and compared their reactivity with that of ovarian, peritoneal, and endometrial serous carcinomas. All primary serous carcinomas of the fallopian tube (13 cases), ovaries (25 cases), and peritoneum (3 cases) were reactive with the WT-1 antibody, whereas all five primary endometrial serous carcinomas were nonreactive. WT-1 reactivity in an unknown primary serous carcinoma is therefore suggestive of an extrauterine site. The marked difference in WT-1 staining raises the possibility of genetic differences between serous carcinomas arising in the endometrium compared with those arising in the ovaries, fallopian tubes, and peritoneum.  相似文献   
27.
H Hara  H Onodera  H Kato  T Araki  K Kogure 《Brain research》1991,545(1-2):87-96
Changes in second messenger and neurotransmitter system receptor ligand binding induced by transient forebrain ischemia were studied in the gerbil hippocampus. The animals were allowed variable periods of recovery ranging from 2 h to 7 days after 5-min bilateral carotid artery occlusion. The binding of second messenger systems ([3H]inositol 1,4,5-trisphosphate ([3H]IP3)to inositol 1,4,5-triphosphate, [3H]forskolin to adenylate cyclase and [3H]phorbol 12,13-dibutylate to protein kinase C) and neurotransmitter receptor systems ([3H]PN200-110 to L-type calcium channels. [3H]N6-cyclohexyl-adenosine to adenosine A1 and [3H]quinuclidinyl benzilate to muscarinic cholinergic receptor) were assayed using quantitative autoradiography. In the CA1 subfield, 2 h after ischemia, [3H]IP3, [3H]forskolin, and [3H]quinuclidinyl benzilate binding activities significantly decreased by 25, 17 and 13%, respectively, though no morphological abnormalities were obvious. Six hours after ischemia, the [3H]phorbol 12,13-dibutylate binding activity in the stratum oriens of the CA1 subfield increased by 15%. One day after ischemia, [3H]PN200-110 binding activity in this subfield decreased by 26%, and 7 days after ischemia, [3H]phorbol 12,13-dibutylate and [3H]N6-cyclohexyl-adenosine receptor binding activities decreased in this subfield. In particular, at 7 days after ischemia, [3H]IP3 binding activity in the CA1 subfield showed a complete decline. In the CA3 subfield, [3H]PN200-110 binding activity decreased 2 days after ischemia, and [3H]IP3 and [3H]N6-cyclohexyl-adenosine binding activities decreased 7 days after ischemia. In the dentate gyrus, the structure of which remained histologically intact after ischemic insult, [3H]IP3 and [3H]forskolin binding activities decreased 7 days after ischemia. In contrast, the [3H]phorbol 12,13-dibutylate binding activity increased in the molecular layer of the dentate gyrus 7 days after ischemia. These results indicate that marked alteration of intracellular signal transduction precedes neuronal damage in the hippocampal CA1 subfield and that the histologically intact CA3 and dentate gyrus also shows modulated neuronal transmission after ischemia.  相似文献   
28.
A study was made on the effect of detection wavelength and separation mode of HPLC on determination of urinary hippuric acid (HA) and three isomers of methylhippuric acid (MHA). The interference of other constituents of urine in the determination was effectively decreased by detection at a short wavelength of 227.6 nm. Meta and para MHAs were separated by the addition of beta-cyclodextrine to the mobile phase. Four metabolites were successfully separated from other components of urine by the combination of ODS-silica packed-column and mobile phase (method F). The detection limits were found to be 50 and 5 mg/l for HA and MHAs, respectively. MHAs could not be detected in the non-exposed subjects. Average levels (+/- SD) of HA in non-exposed males and females were 272.2 (+/- 210.8) and 393.0 (+/- 269.8) mg/l, respectively. The urinary levels of HA in females were significantly higher than those in males.  相似文献   
29.
MRI of the brain in diabetes mellitus   总被引:15,自引:0,他引:15  
We studied the MRI appearances of the brain in 159 patients with diabetes mellitus (DM) and 2566 agematched individuals without DM (controls). The images were reviewed for cerebral infarcts, hemorrhage, atrophy and subcortical arteriosclerotic encephalopathy. Cerebral atrophy was significantly more frequent in patients with DM than in controls (P>0.005) from the sixth to the eighth decade. The frequency of atrophy was 41.2% in the 6th decade, 60.0% in the 7th and 92.3% in the 8th decade in DM, and 19.8%, 38.9% and 56.8% respectively in controls. Unexpectedly, there was no statistically significant difference in the incidences of cerebrovascular diseases at any age.  相似文献   
30.
The word karoshi, i.e. death due to overwork, is not defined for medical diagnosis, but in Japan it means cases of compensation awarded by reason of fatal occupational diseases, particularly ischemic heart diseases and cerebrovascular diseases which are recognized as caused by a heavy workload. Current studies have shown that 1) almost definitely there is evidence of an association between overwork and cardiovascular diseases and the risk factors were found, 2) no reports have been published on evidence of a causal relationship between overwork and fatal effects even though the possibility remains, and 3) the adverse health effects can vary according to workers' characteristics such as gender, age, stress coping and perception. Recently there has been an increase in the proportion of compensated cases versus claims from 3.1% in the 1988 fiscal year to 20.7% in the 2001 fiscal year. This may be related to the deregulation of criteria for compensation, or nintei-kijun. The period of determination of overwork for victims has been extended to a maximum of six months in the newest criteria set in 2001, up from only one week in the criteria set in 1987. According to sociological analysis, long working hours in Japan are related not only to the structure of the working-time system but also the sociocultural background of labor. In 2002, the Japanese government provided the first countermeasures for the prevention of karoshi for all employees stating that they should not work more than 45 h overtime per month and that government intervention in the form of administrative guidance to employees and their employers should be conducted if overtime exceeds 100 h per month. It is a population strategy targeting all workers equally, not just a high-risk strategy targeting only those with some risk factors, and is expected to provide more fruitful results with flexibility, i.e. differentially reinforced management for older workers and those working under highly stressful conditions with harmonization of the production cycle in the workplace. Occupational health professionals such as occupational health physicians and nurses will play a key role in making break-throughs to solve various problems related to karoshi, which may then result in further investigations to provide scientific evidence for policy making.  相似文献   
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