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61.
We reported a 61-year old man with cardioembolic stroke manifested by isolated tonic seizure of the left upper limb. He had a history of chronic atrial fibrillation and transient ischemic attack. He was brought to our hospital by ambulance, when he suddenly had isolated tonic seizure of left upper limb. On admission, he had no neurological symptoms and signs. Brain diffusion weighted MR image disclosed high intensity area in the right parietal lobe, although T2-weighted image did not show any abnormalities. On 8th day, a high intensity area was observed both on the diffusion-weighted and T2-weighted MR images. In case of isolated tonic seizure of left upper limb, careful examination of stroke is required especially if the patient had a high risk of stroke.  相似文献   
62.
Summary In an attempt to clarify the pathobiology of intracranial germ-cell tumors, we studied 56 patients with these tumors, both clinically and pathologically. Our evaluations included immunochemical, immunohistochemical, and electron microscopic observations. Thirty tumors originated in the pineal region, ten in the suprasellar region, nine in the basal ganglia, and two in other regions. Five had double sites of origin. Histologically, there were 39 germinomas, six teratomas, four embryonal carcinomas, two choriocarcinomas and five mixed tumors. Among tumors tested immunochemically, serum carcinoembryonic antigen (CEA) was positive in 3.4%, serum alpha-fetoprotein (AFP) in 25.8%, and serum human chorionic gonadotropin (HCG) in 32.1%. In CSF, CEA was positive in 14.3%, AFP in 26.3%, and HCG in 75%. One third of germinomas were positive for serum HCG, and 88.9% for CSF HCG. One half of teratomas were positive for CEA of CSF. In immunohistochemical testing, the positive rates for CEA, AFP, HCG, and placental alkaline phosphatase (PLAP) were 26.9%, 11.5%, 24.1%, and 55.6%, respectively. Most teratomas were positive for CEA and the reactions were prominant in gland-like structures. HCG-positive syncytial cells were found in three germinomas and two embryonal carcinomas as well as in choriocarcinomas. The majority of germinomas were positive for PLAP and the reactive sites were tumor cell membranes and cytoplasm. On electron microscopy, germinomas were least differentiated, followed in order by embryonal carcinomas, choriocarcinomas, and teratomas. Further clinical and pathological studies will be necessary for a better understanding of the biology of these tumors.  相似文献   
63.
64.
The 3-dimensional shape of the human saccular macula and its orientation in the skull were quantitated in this study. The semicircular canals and saccular maculae were reconstructed 3-dimensionally on a computer from 3 human temporal bones. The 380 to 522 triangles in the entire area of the saccular macula were made by drawing lines between 2 adjacent points every 100-pm width of the saccular macula in each section. The angles between each triangle and each estimated standard axis in the skull obtained were calculated. This information will provide standard data regarding the 3-dimensional morphological aspects of the saccular macula for further investigations of the function of the sacculus. It was determined that the 3-dimensional shape of the saccular macula was not a plane, but was a curved surface like that of an ellipsoid. It is thought that this shape is necessary in order for the saccular macula to detect wide-range linear acceleration.  相似文献   
65.
This study was undertaken to evaluate the role of color Doppler sonography in the preoperative assessment of vascular involvement in patients with pancreatic carcinoma. Twenty-six pancreatic carcinomas were investigated with color Doppler sonography and angiography, and the results of these examinations were compared with those of surgical findings. Color Doppler sonography was more sensitive than angiography in depicting vascular involvement of carcinoma. Thus, it seems rational to perform a preoperative assessment in suspected pancreatic carcinoma patients initially with color Doppler sonography to improve patient management.  相似文献   
66.
Portal vein aneurysm: report of six cases and review of the literature   总被引:4,自引:0,他引:4  
Portal vein aneurysm is very rare, and its relation to portal hypertension has been emphasized. We report six cases of portal vein aneurysm (five extrahepatic and one intrahepatic). All patients were asymptomatic and had no signs suggestive of portal hypertension; the lesion was incidentally detected by ultrasound. Color Doppler sonography showed a constant hepatopetal flow along the aneurysmal wall, which immediately led to the diagnosis. We stress the usefulness of color Doppler sonography for studying the hemodynamics of this vascular anomaly and briefly review the literature. Received: 29 December 1995/Accepted: 14 February 1996  相似文献   
67.
Mesenteric panniculitis: sonographic findings   总被引:3,自引:0,他引:3  
BACKGROUND: Mesenteric panniculitis (MP) is a relatively rare disease, and sonographic (US) and color Doppler findings have been infrequently reported. METHODS: We reviewed the clinical data and US and Doppler results of three cases of MP to determine the role and limitations of these techniques. RESULTS: The sole presenting clinical sign was a soft mass. On US the lesion was imaged as a poorly margined echogenic mass with hypoechoic areas. Color Doppler US visualized the nondeviated mesenteric vessels within the mass, which enabled us to perform a safe guided biopsy. CONCLUSIONS: US is useful as an initial diagnostic tool, but its results must be interpreted carefully. Color Doppler US is very useful in demonstrating fine vessels and helps in performing a safe needle biopsy.  相似文献   
68.
BACKGROUND AND METHODS: Sonographic (US) findings of Chilaiditi syndrome have been rarely reported in the literature. We reviewed 18 cases of Chilaiditi syndrome to pinpoint its US pattern. RESULTS: (1) US showed gas echoes of different sizes superimposed over the entire liver in two cases and over the right hepatic lobe in six cases, leading to a high suspicion of Chilaiditi syndrome. (2) US showed a small gas echo in the hepatodiaphragmatic space, mimicking pneumoperitoneum in eight cases. In this instance, altering the patient's position allowed for confirmation of the lack of a change in the location of the gas echo, unlike cases of pneumoperitoneum. (3) The hepatic surface appeared as a hyperechoic mass in two cases. CONCLUSION: Knowledge of US patterns of Chilaiditi syndrome helps avoid confusion with pneumoperitoneum or hepatic masses.  相似文献   
69.
Background: It is well known that obstructive jaundice causes biliary dilatation, but sonographic (US) findings of the cystic duct in patients with obstructive jaundice are rarely reported. Methods: We reviewed US findings in 25 such patients. Results: US findings of dilated cystic duct could be divided roughly into two patterns: tortuous and tubular. The former pattern was a tortuously dilated cystic duct arising from the gallbladder neck, running predominantly deeply, turning anteromedially, and then joining the posterior face of the common hepatic duct. The latter pattern was a straight dilated cystic duct running parallel with the common hepatic duct, giving the appearance of a septated bile duct. Conclusion: A better understanding of the US findings of dilated cystic duct translates into improved biliary US diagnosis.  相似文献   
70.
Renal arteriovenous malformation: sonographic findings   总被引:2,自引:0,他引:2  
BACKGROUND AND METHODS: Renal arteriovenous malformation (RAVM) is a relatively rare congenital disease. Although sonography (US) currently is the first diagnostic tool for examining the kidney, its US and color Doppler findings have seldom been reported. We reviewed the clinical manifestations and US results of five cases of RAVM to clarify the role and limitations of US in the diagnosis. RESULTS: The lesions were solitary in all cases, and the affected side was the right in four cases and the left in one case. In four cases, the patients complained of hematuria, but the remaining case had no symptoms. US did not detect the lesion, but in all cases color Doppler US showed a focal vascular lesion with posterior color spots. US reexamination with knowledge of the Doppler results did not show any focal lesion. CONCLUSION: US was not diagnostic for RAVM, and color Doppler US should be performed immediately in patients with hematuria.  相似文献   
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