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91.
92.
The aim of this study was to evaluate the sensitivity of the three-dimensional constructive interference of steady state (3D CISS) sequence (slice thickness 0.7 mm) and that of the T2-weighted fast spin echo (T2-weighted FSE) sequence (slice thickness 3 mm) for the visualization of all cranial nerves in their cisternal course. Twenty healthy volunteers were examined using the T2-weighted FSE and the 3D CISS sequences. Three observers evaluated independently the cranial nerves NI–NXII in their cisternal course. The rates for successful visualization of each nerve for 3D CISS (and for T2-weighted FSE in parentheses) were as follows: NI, NII, NV, NVII, NVIII 40 of 40 (40 of 40), NIII 40 of 40 (18 of 40), NIV 19 of 40 (3 of 40), NVI 39 of 40 (5 of 40), NIX, X, XI 40 of 40 (29 of 40), and NXII 40 of 40 (4 of 40). Most of the cranial nerves can be reliably assessed when using the 3D CISS and the T2-weighted FSE sequences. Increasing the spatial resolution when using the 3D CISS sequence increases the reliability of the identification of the cranial nerves NIII–NXII. Received: 29 September 1999; Revised: 2 February 2000; Accepted: 21 March 2000  相似文献   
93.
Monatsschrift Kinderheilkunde -  相似文献   
94.
While the accommodation system has been implicated in myopia development, the nature of this relationship remains obscure. This study investigated the differences in accommodation stimulus response curves between adult myopes and emmetropes. Myopic subjects were classified according to age of onset and stability of their myopia. Accommodation stimulus response curves were measured using three different methods: (i) real targets presented at viewing distances of 4 m to 0.25 m, (ii) a target at 4 m viewed through negative lenses of increasing power, and (iii) a target at 0.25 m viewed through positive lenses of decreasing power. A Canon Autoref R-1 measured the accommodation responses at 5 levels of demand (increasing from 0 D to 4 D in 1 D steps). We found significant differences between the three methods used to stimulate an accommodation response in all subject groups, for example, accommodation lags at high accommodative demands were greatest for the negative lens series and least for the positive lens series. In addition, while differences between early-onset myopes, late-onset myopes and emmetropes were not observed, we did observe differences when myopic subjects were reclassified according to whether their myopia was progressing or stable. A reduced accommodation response to negative lens-induced accommodative demand was found in progressing myopes but not in stable myopes. These results provide further evidence for the link between myopia progression and inaccurate accommodation. The data also suggest that adult myopes with stable refractive errors show accommodation responses similar to that of emmetropes.  相似文献   
95.
Adenylate cyclase (AC) in response to prostaglandin E2 (PGE2) and histamine was studied in morphologically different biopsy specimens from human gastric mucosa. The activities of the enzyme were log-normally distributed and did not differ between males and females. PGE2 activated AC in a concentration-dependent manner in normal gastric mucosa (n = 57), chronic superficial gastritis (GI, 18), chronic gastritis with beginning atrophy (GII, 10), chronic atrophic gastritis (GIII, 24), gastric ulcer (GU, 39), duodenal ulcer (DU, 32), and biopsies of patients operated according to Billroth II (BII, 20) and was most efficacious in GIII and BII. Histamine, which was studied in normal gastric mucosa (n = 27), DU (n = 20), GU (n = 13), and BII (n = 18), stimulated AC most efficaciously and potently in DU, was less effective in normal gastric mucosa and GU, and had no effect at all in BII. Cimetidine treatment of DU patients did not change the PGE2 action, while the degree of stimulation by histamine was reduced. The data indicate characteristic differences of the PGE2- and histamine-sensitive AC in the mucosal samples of these patients.  相似文献   
96.
BackgroundChild welfare and juvenile justice placed youths show high levels of psychosocial burden and high rates of mental disorders. It remains unclear how mental disorders develop into adulthood in these populations. The aim was to present the rates of mental disorders in adolescence and adulthood in child welfare and juvenile justice samples and to examine their mental health trajectories from adolescence into adulthood.MethodsSeventy adolescents in shared residential care, placed by child welfare (n = 52, mean age = 15 years) or juvenile justice (n = 18, mean age = 17 years) authorities, were followed up into adulthood (child welfare: mean age = 25 years; juvenile justice: mean age = 27 years). Mental disorders were assessed based on the International Classification of Diseases 10th Revision diagnoses at baseline and at follow-up. Epidemiological information on mental disorders was presented for each group. Bivariate correlations and structural equation modeling for the relationship of mental disorders were performed.ResultsIn the total sample, prevalence rates of 73% and 86% for any mental disorder were found in adolescence (child welfare: 70%; juvenile justice: 83%) and adulthood (child welfare: 83%; juvenile justice: 94%) respectively. General psychopathology was found to be stable from adolescence into adulthood in both samples.ConclusionsOur findings showed high prevalence rates and a high stability of general psychopathology into adulthood among child welfare and juvenile justice adolescents in Swiss residential care. Therefore, continuity of mental health care and well-prepared transitions into adulthood for such individuals is highly warranted.  相似文献   
97.
98.
Previous work has shown that chemically induced oxidative stress disrupts the protein interactions of the E-cadherin/beta-catenin/alpha-catenin complex in precision-cut mouse liver slices (Parrish et al., 1999, Toxicol. Sci. 51, 80-86). Although these data suggest a role for oxidative stress in disruption of hepatic cadherin/catenin complexes, multiple complexes are co-expressed in the liver. Both E- and N- cadherin are co-expressed in hepatocytes, as well as beta-catenin and gamma-catenin; thus four distinct complexes mediate cell-cell adhesion in the liver: E-cadherin/beta-catenin/alpha-catenin, E-cadherin/gamma-catenin/alpha-catenin, N-cadherin/beta-catenin/alpha-catenin, and N-cadherin/gamma-catenin/alpha-catenin. Taking advantage of the retention of normal organ architecture and cellular heterogeneity offered by precision-cut mouse liver slices, the current study was designed to examine the impact of chemically induced oxidative stress on cadherin/catenin complexes. Precision-cut mouse liver slices were challenged with diamide (25-250 microM; 6 h) or tert-butylhydroperoxide (5-50 microM; 6 h). A polyclonal antibody against beta- or gamma-catenin was used to immunoprecipitate proteins prior to Western-blot analysis with monoclonal antibodies to E- or N-cadherin. Although a decrease in E-cadherin:beta-catenin co-immunoprecipitation was seen, interactions between beta-catenin and N-cadherin were not disrupted by chemical challenge. In addition, no effect on protein interactions of gamma-catenin with either cadherin was observed. Indirect immunofluorescence was used to co-localize catenins and cadherins following chemical challenge. Consistent with the biochemical observations, a heterogeneous reduction in co-localization of E-cadherin and beta-catenin was seen in precision-cut liver slices, but not other cadherin/catenin complexes. Taken together, these data suggest that oxidative stress selectively disrupts E-cadherin/beta-catenin complexes in the liver. This response is dictated, in part, by the protein composition of the cell-adhesion complex.  相似文献   
99.
100.

Objectives

Neoadjuvant therapy with a platinum based doublet is an option in NSCLC patients with upfront resectable disease. However, the role of neoadjuvant induction in stages IIIA and IIIB and in initially not resectable patients is unclear.

Patients and methods

In this phase II trial, 78 patients with locally advanced NSCLC, of whom 56 were considered not resectable at initial diagnosis, were treated with three neoadjuvant cycles of docetaxel and cisplatin and subjected to radical surgery if resectable. Definitive radiochemotherapy (RCT) using weekly docetaxel was the prespecified alternative if patients were not resectable at restaging. The primary objective was response to neoadjuvant induction.

Results

After induction, 36 (46%) were radically operated and 24 (31%) were treated with RCT. Overall, 32 patients (41%) completed the entire study plan. Partial response to induction therapy was observed in 43 patients (55%); furthermore, 19 of 56 initially not resectable cases (34%) became resectable upon induction. Median progression-free (PFS) and overall survival (OS) were 8.5 and 16.4 months for the whole cohort. Encouragingly, conversion to resectability was predictive for favorable outcome. On the other hand, patients who were not resectable at restaging and received RCT were characterized by a rather unfavorable prognosis (5-year and 10-year OS, whole cohort: 20% and 12%; RCT: 8% and 0%; surgery: 37% and 24%, respectively).

Conclusion

Neoadjuvant induction with the doublet docetaxel/cisplatin and subsequent radical resection resulted in favorable survival. Of note, conversion to resectability was mandatory for the chance of cure in patients considered initially not resectable.  相似文献   
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