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991.
BACKGROUND: The location and clinical impact of solitary lymph node metastasis from thoracic esophageal carcinoma have not been evaluated sufficiently. METHODS: A consecutive series of 91 patients with a solitary positive lymph node who underwent curative surgery for thoracic esophageal carcinoma was investigated. The prognostic impact was evaluated by univariate analysis and multivariate analysis using Cox's proportional hazards model. RESULTS: A total of 52 (57%) of the 91 patients showed a solitary positive node beyond the thorax. While 29% of the patients with an upper thoracic tumor showed a cervical node, 13% of the patients with a middle tumor and none of the patients with a lower tumor showed a cervical node. Tumor depth and venous invasion were found to be independent risk factors for poor survival. CONCLUSIONS: The solitary positive lymph nodes were broadly distributed depending on the tumor location and tumor depth. Tumor depth and venous invasion were risk factors for poor survival in these patients.  相似文献   
992.
Purpose Clinical trials of carbon ion therapy have been performed due to the advantages of high-dose energy delivery with precise localization control to targeted organs and strong cell-killing activities to cancers. Perforated intestines as a late morbidity after carbon ion radiotherapy for uterine cancers were examined to reveal the biological characteristics of carbon ion for future applications for the treatment of gastrointestinal cancers. Methods Between June 1995 and December 2004, 94 patients with carcinoma of the uterine cervix or corpus were treated with carbon ion therapy. Among them, 9 patients (9.6%) developed major late gastrointestinal (GI) complications. Four out of 9 patients had intestinal perforations excised operatively at our institute. The postoperative clinical courses and histopathological findings of the excised intestine were investigated. Results Carbon ion irradiation severely damaged smooth muscle layers by coagulation necrosis as well as atrophy of the intestinal epithelium and middle-sized arterial thromboses of the intestines. After evaluating late complications, the dose constraints on the GI tracts were set under 60 GyE to prevent major complications. Thereafter, the incidence of major GI complications markedly decreased. Conclusion Our findings demonstrated the characteristic histopathological effects of carbon ion radiotherapy and thus are expected to facilitate future additional applications of carbon ion radiotherapy for the treatment of gastrointestinal cancers.  相似文献   
993.
We report our experience in carotid stenting via the transbrachial approach in patients with anomalous origin of the left common carotid artery, the so-called bovine arch, in which both the right common carotid artery and the left common carotid artery arise from the brachiocephalic artery. Via percutaneous access to the right brachial artery, a 6Fr Shuttle sheath is advanced into the aortic arch to cannulate the left common carotid artery. A Guardwire distal-protection balloon is positioned within the left internal carotid artery distal to the stenosis. The lesion is dilated, followed by satisfactory deployment and dilation of a 6Fr Precise stent. Carotid stenting via the brachial artery in bovine arch appears feasible as an alternative to standard femoral access.  相似文献   
994.
Background The prevalence of gastroesophageal reflux disease (GERD) has reportedly risen in recent years. Difficulties associated with endoscopic diagnosis mean it is not easy to determine its precise prevalence. A prospective study of the prevalence of endoscopy-positive GERD (EP-GERD) was conducted at Higuchi Hospital, a general hospital in Northwestern Kyushu, Japan. The study also correlated factors that might affect prevalence (age, sex, and functions of the gastroesophageal junction). Methods From consecutive patients undergoing endoscopic examination at Higuchi Hospital between January 2000 and April 2003, 1234 patients without severe complications were examined for the possible presence of GERD. Patients were stratified by age and sex, and the prevalence in each group ascertained. EP-GERD was defined on the four-level scale of the Los Angeles classification. Endoscopic classification of gastroesophageal flap valve ([GEFV] functional anomalie; using a four-level scale), was done as proposed by Hill et al. in 1996, to assess flap-valve morphology. Six items were evaluated: (1) symptoms and primary diseases; (2) prevalence of development of EP-GERD classified by age and sex; (3) endoscopic morphology of the GEFV as an expression of the functions of the gastroesophageal junction, and its prevalence by age and sex; (4) regression analysis and Spearman's rank correlation of GEFV and EP-GERD grades; (5) prevalence of EP-GERD and GEFV stratified by age and analyzed; and (6) multiple regression analysis of EP-GERD and explanatory variables (age, sex, and GEFV). Results The overall prevalence of EP-GERD was 5.8% (72/1234) and this patient group was dominated by men. Aging had minimal effect on prevalence in men, but the prevalence rose among women as they aged. The age-stratified prevalence of GEFV functional anomalies was similar to the age-stratified prevalence of EP-GERD in both sexes. The correlation between EP-GERD and GEFV functional anomalies was high regardless of sex. Conclusions We postulate that the mechanisms leading to the development of GEFV functional anomalies in men are different from those in women. Future evaluations of EP-GERD should also observe GEFV function.  相似文献   
995.
Two cases in whom the subsegmental biliary branch of the anterio-inferior area (B5) coursed to the right laterally and inferiorly, forming a caudally convex arc, and running near the neck of the gallbladder are reported. In these two patients, the B5 branches were not aberrant, however, these branches were running near the gallbladder bed extrahepatically, which alerted us to the risk of their inadvertent division. The relationship between the cystic duct and the B5 branch is clinically important during cholecystectomy, especially laparoscopic cholecystectomy.  相似文献   
996.
997.
INTRODUCTION: The ventricular apex has a helical arrangement of myocardial fibers called the "vortex cordis." Experimental studies have demonstrated that the first postshock activation originates from the ventricular apex, regardless of the electrical shock outcome; however, the related underlying mechanism is unclear. We hypothesized that the vortex cordis contributes to the initiation of postshock activation. To clarify this issue, we numerically studied the transmembrane potential distribution produced by various electrical shocks. METHODS AND RESULTS: Using an active membrane model, we simulated a two-dimensional bidomain myocardial tissue incorporating a typical fiber orientation of the vortex cordis. Monophasic or biphasic shock was delivered via two line electrodes located at opposite tissue borders. Transmembrane potential distribution during the monophasic shock at the center of the vortex cordis showed a gradient high enough to initiate postshock activation. The postshock activation from the center of the vortex cordis was not suppressed, regardless of the initiation of spiral wave reentry. Spiral wave reentry was induced by the monophasic shock when the center area of the vortex cordis was partially excited by the nonuniform virtual electrode polarization. Postshock activation following the biphasic shock also originated from the center of the vortex cordis, but it tended to be suppressed due to the narrower excitable gap around the center of the vortex cordis. The electroporation effect, which was maximal at the center of the vortex cordis, is another possible mechanism of postshock activation. CONCLUSION: Our simulations suggest that the vortex cordis may cause postshock activation.  相似文献   
998.
TP53-inducible genes play crucial roles from many biological aspects including cell cycle control, DNA repair, and apoptosis. Herein we report the identification and characterization of a novel TP53-inducible gene, DSCP1 (damage stimulated cytoplasmic protein 1), localized at 17q11. The gene was expressed ubiquitously in normal adult tissues; its protein product was localized mainly in the cytoplasm with anchoring on unknown subcellular structures. Exogenous expression of TP53 induced expression of DSCP1, but more interestingly, DSCP1 was induced by strong genotoxic stresses not only in TP53-maintaining cells but also in TP53-dysfunctioning cells, although the induction was much more efficient in the former than in the latter. In cultured cancer cells, the basal expression level appeared to depend on the functional status of TP53. Moreover, exogenous overexpression of DSCP1 retarded cancer cell growth in vitro. These results indicate that DSCP1 is a stress-inducible gene in both a TP53 dependent and independent manner and that its protein product can inhibit cancer cell growth.  相似文献   
999.
1000.
A cDNA library of maternal messages was constructed from non-fertilized Bombyx mori eggs collected just after oviposition without mating. cDNA clones were identified by their nucleotide sequences and evaluated as probes for RFLP linkage analysis. Back crossed F1 segregants - by crossing an F1 female (RF02 x RF50) and a male (RF02) - were used, which takes advantage of the phenomenon that no crossing over occurs in Bombyx females. Fifteen ordered BF1 segregants gave either homozygous (homo) or heterozygous (hetero) RFLP patterns with each cDNA probe. cDNA probes on the same linkage group gave the same homo/hetero order. One hundred and fifty one out of 248 cDNA clones showed polymorphisms between RF02 and RF50, and were therefore suitable as probes for RFLP linkage analysis in the present BF1 cross. They were sorted into twenty-seven linkage groups and one independent group, by the homo/hetero pattern matrix, covering all twenty-eight chromosomes in B. mori.  相似文献   
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