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71.
Objective: The diagnosis of small-sized (2 cm or less) non-small cell lung cancer (NSCLC) has increased with the development of computed tomography (CT), whereas unexpected extensive multiple-level mediastinal involvement has been occasionally detected in this small-sized lung cancer. To establish the optimal surgical strategy, we retrospectively analyzed the clinicopathologic features, efficacy of preoperative investigations and lobe specific patterns of nodal spread in small-sized NSCLC with mediastinal involvement. Methods: Among 1550 resected lung cancer cases between 1981 and 2000, 267 (17.2%) had peripheral small-sized NSCLC. Of these, 29 patients (10.8%) with mediastinal lymph node involvement who underwent pulmonary resection and systematic nodal dissection were reviewed. Results: Among 29 patients, 27 patients (93.1%) were adenocarcinoma, and 51.7% (15/29) showed no lymph node enlargement on CT (cN0). Surgical pathology revealed multiple-level mediastinal involvement in 65.5% (19/29) of all patients and 60.0% (9/15) of cN0 patients. All of right upper lobe tumors (n=11) showed multiple-level involvement. Thallium-201 single photon emission computed tomography (201Tl-SPECT) was positive for increased focal uptake in the mediastinum in 72.7% (8/11) of patients. Conclusions: The vast majority of cases were adenocarcinoma, and two thirds of them showed multiple-level mediastinal involvement, even in cN0 patients. We thus recommend to perform systematic nodal dissection or meticulous sampling for accurate intrathoracic staging, especially for right upper lobe tumor. 201Tl-SPECT appears to be more sensitive preoperative investigation for mediastinal metastasis compared with CT scan.  相似文献   
72.
Circulating osteoprotegerin is not removed through haemodialysis membrane.   总被引:1,自引:1,他引:0  
Sir, We read with interest the study of Coen et al. [1], which suggesteda possible relationship between circulating osteoprotegerin(OPG) and bone metabolism in uraemic patients. We also reportedthat circulating OPG levels were elevated in dialysis patientsand  相似文献   
73.
Ring 14 chromosome with complex partial seizures: a case report.   总被引:2,自引:0,他引:2  
A two-year-old girl was found to have a ring 14 chromosome: [46, XX, r(14) (P13 q32.3)]. Her development, including verbal ability, was retarded, her CT scan displayed a low density area anterior to the left temporal lobe, and she suffered from complex partial seizures. Focal central nervous system abnormalities may be present in patients with ring 14 chromosome, and their seizures are not exclusively of the primary generalized type. This is the first case with ring 14 chromosome and complex partial seizures.  相似文献   
74.
The antiviral activity of azidothymidine (AZT), dideoxycytidine (ddC), and dideoxyinosine (ddI) against HIV-1 was comparatively evaluated in PHA-stimulated PBM. The mean drug concentration which yielded 50% p24 Gag negative cultures were substantially different: 0.06, 0.2, and 6 microM for AZT, ddC, and ddI, respectively. We found that AZT was preferentially phosphorylated to its triphosphate (TP) form in PHA-PBM rather than unstimulated, resting PBM (R-PBM), producing 10- to 17-fold higher ratios of AZTTP/dTTP in PHA-PBM than in R-PBM. The phosphorylation of ddC and ddI to their TP forms was, however, much less efficient in PHA-PBM, resulting in approximately 5-fold and approximately 15-fold lower ratios of ddCTP/dCTP and ddATP/dATP, respectively, in PHA-PBM than in R-PBM. The comparative order of PHA-induced increase in cellular enzyme activities examined was: thymidine kinase > uridine kinase > deoxycytidine kinase > adenosine kinase > 5'-nucleotidase. We conclude that AZT, ddC, and ddI exert disproportionate antiviral effects depending on the activation state of the target cells, i.e., ddI and ddC exert antiviral activity more favorably in resting cells than in activated cells, while AZT preferentially protects activated cells against HIV infection. Considering that HIV-1 proviral DNA synthesis in resting lymphocytes is reportedly initiated at levels comparable with those of activated lymphocytes, the current data should have practical relevance in the design of anti-HIV chemotherapy, particularly combination chemotherapy.  相似文献   
75.

Background

Avascularity of the bleb is regarded as a risk of bleb infection, which is the most serious complication after filtration surgery with mitomycin C (MMC). There is no perfect way to prevent avascular bleb formation. We hypothesized that keeping the conjunctiva away from direct exposure to aqueous filtration may suppress avascular bleb formation after filtration surgery with MMC. In order to prove our hypothesis, we investigated whether a thin biodegradable, honeycomb-patterned film (HPF) can reduce bleb avascularity in a rabbit model of filtration surgery with mitomycin C (MMC).

Methods

A fornix-based full-thickness filtration surgery was performed in one eye of each of five rabbits (control group). The same surgery with intraoperative MMC treatment was done in both eyes of six rabbits, with one eye receiving a 14-μm-thick HPF made from poly(L-lactide-co-ε-caprolactone), which was placed subconjunctivally over the filtration site with the honeycomb surface facing up. Intraocular pressure (IOP) measurements, bleb evaluations using ultrasound biomicroscopy (UBM), and in vivo confocal microscopy (IVCM) were performed periodically for 4?weeks postoperatively followed by histological examination.

Results

The postoperative IOP decrease and bleb survival were significantly greater in MMC-treated eyes than in control eyes, and were similar between MMC-only and MMC + HPF eyes. The avascular area in the bleb persisted for 4?weeks in MMC-only eyes. Postoperative IVCM showed morphological changes of the conjunctival epithelial cells (i.e., enlarged and variable in size and shape) and epithelial defects in MMC-only eyes, and significantly lower density of connective tissue and vascularity in the subepithelial space in MMC-only eyes compared to the control eyes. These IVCM findings agreed with those by UBM and histology. Bleb avascularity shown by clinical bleb appearance, IVCM and histology, conjunctival epithelial damage shown by IVCM and histology, and loose subepithelial connective tissue shown by UBM, IVCM, and histology were all reduced in MMC + HPF eyes compared to MMC-only eyes.

Conclusions

IVCM successfully showed the characteristic conjunctival damage in MMC-treated blebs. The concomitant use of a thin biodegradable HPF reduced avascularity and conjunctival damage in blebs, without compromising filtration in rabbits following filtration surgery with MMC.  相似文献   
76.
Flat-type colorectal tumors have are being detected with increasing frequency. It has become clear that these flat lesions contain two subtypes; flat-elevated and depressed lesions. However, their clinicopathological features and roles in colorectal carcinogenesis remain obscure. We classified colorectal adenomas and submucosal invasive cancers into three types: polypoid, flat-elevated, and depressed types. A clinicopathological study of 2505 colorectal tumors (2407 adenomas, 98 submucosal invasive cancers) was then performed. Furthermore, 64 tumors (25 adenomas with high-grade dysplasia, 39 submucosal invasive cancers) from which DNA was extracted were examined for K-ras gene mutation. The percentages of each configuration in the resected materials were 62.0%, 36.4%, and 1.6% of the polypoid, flat-elevated, and depressed types, respectively. The rate of submucosal invasive cancer in the depressed type was always high regardless of size. In the polypoid and flat-elevated types, lesions of larger size showed higher rates of invasion. Analysis of submucosal invasive cancers revealed no adenomatous components in any of the depressed-type lesions; in the polypoid and flat-elevated types the frequencies of cancer with adenomatous components were 83.6% and 77.8%, respectively. The flat-elevated type was more frequently located (77.8%) in the proximal colon than the other types (polypoid type 16.4%, depressed type 25.0%). The incidence of K-ras gene mutation was 47.2%, 18.2%, and 0% in the polypoid, flat-elevated, and depressed types, respectively. These findings suggest that the flat-elevated and depressed types are similar in that they are both morphologically flat and have infrequent incidences of K-ras gene mutation, but these two lesions differ in their pathological features. Especially, depressed type lesions have a tendency to invade the submucosal layer even when they are small. Therefore one should always be aware of this type of lesion during colonoscopic examination.  相似文献   
77.

Purpose  

Nerve growth factor (NGF) has been reported to affect synaptic transmission and cause neuropathic pain. In contrast, lidocaine has been used to reduce neuropathic pain; however, the effect of NGF and lidocaine on spontaneous transmitter release and synapse excitation has not been fully defined. Therefore, the effect of NGF and lidocaine on nerve regeneration, synapse reformation, and subsequent spontaneous transmitter release was investigated. We used Lymnaea stagnalis soma–soma-identified synaptic reconstruction to demonstrate that a transient increase in both frequency and amplitude of spontaneous events of miniature endplate potentials (MEPPs) occurs following NGF treatment and a short burst of action potentials in the presynaptic cell; in addition, the effect of lidocaine on NGF-induced synapse reformation was investigated.  相似文献   
78.
79.
Background: Occlusion due to tumor ingrowth is a major drawback in self‐expandable metallic stents. Covering the stent is a probable solution to prevent tumor ingrowth. A manufactured covered self‐expandable metallic stent, Covered Wallstent, has become commercially available. We evaluated the Covered Wallstent in a prospective uncontrolled multicenter setting. Methods: Between October 2001 and October 2003, 97 patients with common bile duct strictures deemed unfit for surgical resection underwent placement of a single Covered Wallstent, and were followed prospectively until April 2004. Results: Placement of the stent was successful in all the patients attempted. As a procedure‐related complication, acute pancreatitis developed in four patients, in one of whom obstruction of the pancreatic duct orifice with the stent body seemed to be a major cause. The 30‐day mortality was 9.3% (nine patients). Stent occlusion occurred in 22 patients as a late (greater than 30 days) complication, due to either tumor overgrowth (14 patients) or encrustation (eight patients). Distal migration of the stent was demonstrated in two other patients. No stent occlusions due to tumor ingrowth were observed. Patency rates of the stent for 3‐, 6‐, and 12‐month periods were, respectively, 90.7, 82.5, and 45.9%. Conclusions: The present results in a large series suggest that placement of the Covered Wallstent is feasible and effective in the palliation of patients with malignant common bile duct strictures. The Covered Wallstent seems to be reliable in eliminating tumor ingrowth. The role of stent covering in promoting stent function should be examined in a prospective comparative study between covered‐ and uncovered Wallstents.  相似文献   
80.
To analyze the correlation between muscle sympathetic nerve activity (MSNA) and cardiac (123)I-metaiodobenzylguanidine (MIBG) uptake in patients with Parkinson's disease (PD), we measured both parameters in 14 PD patients who were 51 to 82 years of age (mean, 63.1 +/- 8.7 years). The duration of PD was 2 to 26 years, and the disability level (modified Hoehn and Yahr stage) ranged from 2.0 to 4.0 (mean, 3.2 +/- 0.5). MSNA was recorded from the peroneal nerve fascicles using microneurographic methods, and then cardiac MIBG scintigraphy was performed within 1 month. We analyzed the correlation between the standardized MSNA, expressed as a percentage of the predicted value based on control subject data, and the heart-to-mediastinum ratio (H/M) or washout ratio (WR) from early and delayed MIBG images. The relationships between disease duration or disability and MSNA, the H/M ratio, or the WR were also analyzed. No significant correlations were found between MSNA and H/M ratio or WR. Although MSNA was inversely correlated with disease duration and with disability level, neither the H/M ratio nor the WR showed a significant correlation with disease duration or disability level. Because MSNA and MIBG abnormalities were not related, functional changes in addition to organic changes in cardiac sympathetic nerve endings may result in abnormal uptake of MIBG in Parkinson's disease. .  相似文献   
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