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71.
1. The present study analysed the clinical course, the serial angiograms and the CT scans of the patients with angiographic arterial occlusion following vasospasm after subarachnoid hemorrhage. The occlusion was observed in 6 out of 84 patients with vasospasm. 2. The angiograms which showed this phenomenon were obtained between the 11th and the 30th day of the illness. The affected vessels were the branches of middle cerebral artery. 3. Thrombus formed on the intima which had been injured by vasospasm is suspected to be a genesis of this arterial occlusion. The pathological findings of a case in this series support this concept. 4. The surgical procedure during the direct aneurysmal operation performed in the period of "smooth narrowing" seems to be a contributing factor to the arterial occlusion. There was no correlation between antifibrinolytic therapy and this phenomenon except in one case. 5. Fibrinolytic therapy after clipping of aneurysm may be a treatment of choice for this arterial occlusion following vasospasm.  相似文献   
72.
There are three types of endoscopic surgery in obstetrics and gynecology: laparoscopy; hysteroscopy; and salpingoscopy. The main indications for laparoscopic surgery are myoma uteri, ovarian tumors, ectopic pregnancy, infertility, and endometriosis. Currently the indications are limited to benign disease. The main indications for hysteroscopic surgery are submucous myoma uteri, uterine anormalies, and Asherman syndrome. During hysteroscopy the uterine cavity is dilated with liquid and then a resectoscope or hysterofiberscope is used. Salpingoscopy is useful in examining the tubal cavity and a potent tool for tubal recanalization. Endoscopic surgical techniques will develop rapidly in the near future to serve the various needs of female patients.  相似文献   
73.
BACKGROUND: Advanced glycation end products (AGEs) accumulate on tissue and plasma proteins in patients with renal failure far in excess of normal aging or diabetes. The aim of these studies was to elucidate the nature of the precursors and the pathways that lead to an accelerated formation of two structurally identified AGEs [pentosidine and Nepsilon(carboxymethyl)lysine (CML)] in the uremic milieu. METHODS: Serum levels of the glycoxidation products, pentosidine and CML, were quantitated by high-performance liquid chromatography in uremic patients treated by dialysis. The formation of early glycation products (as furosine) and late glycoxidation products was modeled in uremic serum and in spent peritoneal dialysate. RESULTS: Clinical factors that affect circulating levels of AGEs included dialysis clearance and dialyzer membrane pore size, but not the presence or absence of diabetes. Both pentosidine and CML form at an accelerated rate in serum from uremic patients. Chelating agents most effectively slow the formation in vitro. In uremic fluids, the primary mechanism of formation of pentosidine is through the Amadori pathway. The primary mechanism of formation of CML is through metal-chelated autoxidation of reducing sugars generating reactive carbonyl precursors. In uremic serum, the presence of an unidentified reactive low molecular weight precursor accelerates the formation of pentosidine. CONCLUSIONS: The formation of the two glycoxidation products, pentosidine and CML, proceeds by different pathways and is enhanced by different precursors in the uremic milieu. The formation of both AGEs is markedly enhanced by metal-catalyzed reactions, evidence for the presence of increased metal-ion mediated oxidant stress in uremia.  相似文献   
74.
To examine the effects of 2,5-hexanedione (HD) on the glucose metabolism in the spinal cord, glucose utilization rate (GUR) and distribution volume of glucose (DV) were measured in the white matter and anterior horn of the spinal cord in 8 rats exposed to HD for 4 weeks and in 10 control rats. The GUR and DV were determined by the quantitative microdetermination method using non-tracer 2-deoxyglucose based on the three-compartments model of Sokoloff. GURs in the white matter and anterior horn and DV in the anterior horn in the HD-exposed rats were significantly lower than those in the control rats. In the multiple regression analysis, GUR in the white matter of HD-exposed rats was significantly related to blood HD concentration. It is suggested that the decrease of GUR in the white matter is a major effect of HD in the spinal cord.  相似文献   
75.
To examine the effects of lead on glucose metabolism in the spinal cord, glucose utilization rate (GUR) and distribution volume of glucose (DV) in the anterior horn and white matter were determined in 9 rats exposed to lead for 4 weeks and 10 control rats. The GUR and DV were determined by the quantitative microdetermination method using non-tracer amount of 2-deoxyglucose based on the three-compartments model of Sokoloff. The GUR and DV in the anterior horn in the lead-exposed rats were significantly lower than those in the controls. It is thus suggested that glucose metabolism, as measured by the GUR and DV, in the anterior horn is inhibited by lead; the anterior horn cells seem sensitive to lead neurotoxicity.  相似文献   
76.
Loss of heterozygosity (LOH) of chromosome 10q is observed in approximately 40% of endometrial cancers. Mutations in PTEN/MMAC1 , a gene recently isolated from the 10q23 region, are responsible for two dominantly inherited neoplastic syndromes, Cowden disease and Bannayan-Zonana syndrome. Somatic mutations of this gene have also been detected in sporadic cancers of the brain, prostate and breast. To investigate the potential role of this putative tumor suppressor gene in endometrial carcinogenesis as well, we examined 46 primary endometrial cancers for LOH at the 10q23 region, and for mutations in the entire coding region and exon-intron boundaries of the PTEN/MMAC1 gene. LOH was identified in half of the 38 informative cases, and subtle somatic mutations were detected in 15 tumors (33%). Our results suggest that of the genes studied so far in endometrial carcinomas, PTEN/MMAC1 is the most commonly mutated one, and that inactivation of both copies by allelic loss and/or mutation, a pattern that defines genes as "tumor suppressors,'contributes to tumorigenesis in endometrial cancers.  相似文献   
77.
Soapfishes contain peptide toxins (grammistins) in the skin secretion. Two grammistins (Gs 1 and Gs 2) and six grammistins (Pp 1, Pp 2a, Pp 2b, Pp 3, Pp 4a and Pp 4b) have already been isolated from Grammistes sexlineatus and Pogonoperca punctata, respectively. In this study, five grammistins (Gs A-E), together with grammistins Gs 1 and Gs 2, were further isolated from G. sexlineatus by gel filtration and reverse-phase HPLC. Sequence analyses revealed that grammistins Gs A (28 residues) and Gs C (26 residues) are analogous to grammistin Pp 3 and grammistin Gs B (12 residues) to grammistin Pp 1, while grammistins Gs D (13 residues) and Gs E (13 residues) are identical with grammistins Pp 1 and Pp 2b, respectively. Grammistins Gs A-C exhibited antibacterial activity with a broad spectrum against nine species of bacteria in common with the other grammistins but had no hemolytic activity differing from the other grammistins. Grammistins Gs A-E, Gs 1 and Gs 2 could release carboxyfluorescein entrapped within liposomes made of either phosphatidylcholine or phosphatidylglycerol/phosphatidylcholine (3:1), demonstrating their membrane-lytic activity. However, no clear relationship between the membrane-lytic activity and the biological activity of grammistins was recognized.  相似文献   
78.
A new technique, simultaneous display of magnetic resonance angiography (MRA) and multiplanar reconstruction (MPR), was performed by a workstation to identify the involved vessels in patients with trigeminal neuralgia (TN) or hemifacial spasm (HFS), and the results were compared with those of oblique sagittal MRI technique. Twelve patients with either HFS or TN were prospectively assessed by simultaneous display of MRA and MPR, and oblique sagittal techniques, to point out the neurovascular compression and to identify the involved vessels. Three-dimensional (3D) time-of-flight (TOF) spoiled gradient-echo (SPGR) images were acquired to create MRA and MPR. Oblique sagittal views were also created and displayed on films. A total of 15 vessels in 12 patients were identified as compressing vessels during surgery. Simultaneous display of MRA and MPR technique pointed out the presence of vessels at and/or around root entry/exit zone (REZ) in all 12 patients, but proper identification by the name of the individual vessel was correct in 13 of 15 cases. However, oblique sagittal technique indicated the presence of vessels at and/or around REZ in 11 patients, but only 8 of 14 vessels were correctly identified. Our new method, simultaneous display of MRA-MPR, facilitated correct identification of the involved vessels compared with the oblique sagittal view method. Received: 30 June 1999; Revised: 9 September 1999; Accepted: 23 November 1999  相似文献   
79.
BACKGROUND: The tensile strength in intestinal anastomoses decreases postoperatively in association with degradation of the extracellular matrix, and these changes would be expected to be more intense in the presence of peritonitis. MATERIALS AND METHODS: In this study, we investigated extracellular matrix degradation and tensile strength in a rat model of intestinal anastomosis with peritonitis. In the chemical peritonitis model, peritonitis was induced 24 h earlier with intraperitoneal HCl. A serine protease inhibitor, nafamostat mesilate (NM), was given intraperitoneally to some animals every 12 h from immediately after the operation for 3 days. Immunostaining was performed by the standard streptavidin-biotin-peroxidase method after fibronectin (Fn) and factor XIII antigen retrieval on paraformaldehyde-fixed, paraffin-embedded tissue sections. RESULTS: In comparison with controls, administration of NM reduced the loss of tensile strength on Day 3 in a dose-dependent manner, and high-dose NM (20/mg/kg) significantly prevented the loss of tensile strength on Day 3 (P < 0. 05). In the control group, degradation of the collagen layer in the anastomosis was associated with disappearance of Fn and factor XIII staining on Day 3. The administration of NM attenuated these changes with intense immunostaining for Fn and factor XIII seen particularly between collagen fibers on both sides of the anastomosis on Day 3. In the chemical peritonitis model, administration of NM also significantly prevented the loss of tensile strength on Day 3 without disappearance of collagen fibers. CONCLUSION: These findings suggest that NM may be clinically useful for preventing intestinal leakage, particularly when anastomoses are performed under protease-activating conditions, such as intestinal edema and inflammation.  相似文献   
80.
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