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111.
The efficiency of the respiratory system presents significant limitations on the bodys ability to perform exercise due to the effects of the increased work of breathing, respiratory muscle fatigue, and dyspnoea. Respiratory muscle training is an intervention that may be able to address these limitations, but the impact of respiratory muscle training on exercise performance remains controversial. Therefore, in this study we evaluated the effects of a 12-week (10 sessions week–1) concurrent inspiratory and expiratory muscle training (CRMT) program in 34 adolescent competitive swimmers. The CRMT program consisted of 6 weeks during which the experimental group (E, n=17) performed CRMT and the sham group (S, n=17) performed sham CRMT, followed by 6 weeks when the E and S groups performed CRMT of differing intensities. CRMT training resulted in a significant improvement in forced inspiratory volume in 1 s (FIV1.0) (P=0.050) and forced expiratory volume in 1 s (FEV1.0) (P=0.045) in the E group, which exceeded the S groups results. Significant improvements in pulmonary function, breathing power, and chemoreflex ventilation threshold were observed in both groups, and there was a trend toward an improvement in swimming critical speed after 12 weeks of training (P=0.08). We concluded that although swim training results in attenuation of the ventilatory response to hypercapnia and in improvements in pulmonary function and sustainable breathing power, supplemental respiratory muscle training has no additional effect except on dynamic pulmonary function variables.  相似文献   
112.
CONTEXT: Primary lymphoma of the urinary bladder is rare. Only 84 cases have been reported in the English literature to date, and none of these cases has had molecular confirmation of clonal immunoglobulin gene rearrangement. OBJECTIVES: To review all cases with primary urinary bladder lymphoma in our records, to classify them using the REAL classification, to confirm their immunophenotype and genotype, and to determine their outcome. DESIGN: We identified 4 cases of primary urinary bladder lymphoma in our medical records from a 30-year period. Immunohistochemical detection of immunoglobulin light chains and molecular analysis of immunoglobulin heavy-chain genes using the polymerase chain reaction were performed on paraffin-embedded material. RESULTS: All patients were older than 60 years. The male-female ratio was 1:3. All patients had a history of chronic cystitis. Histologic features of mucosa-associated lymphoid tissue lymphoma with centrocyte-like cells, plasmacytoid B cells, or both were observed in all cases. Monoclonality of B cells was demonstrated by immunohistochemistry, polymerase chain reaction, or both methods in every case. All patients presented with stage IAE disease, were treated with radiotherapy alone, and have been in continuous complete remission for 2 to 13 years. CONCLUSIONS: Primary bladder lymphomas are usually of low-grade mucosa-associated lymphoid tissue type. They are more common in females and are associated with a history of chronic cystitis. Lymphoepithelial lesions are seen only in association with areas of cystitis glandularis. B-cell clonality is readily demonstrable by immunohistochemistry and/or polymerase chain reaction analysis. Local radiotherapy appears to confer long-term control.  相似文献   
113.
BACKGROUND: Patients who have a first episode of venous thromboembolism in the absence of known risk factors for thrombosis (idiopathic thrombosis) are often treated with anticoagulant therapy for three months. Such patients may benefit from longer treatment, however, because they appear to have an increased risk of recurrence after anticoagulant therapy is stopped. METHODS: In this double-blind study, we randomly assigned patients who had completed 3 months of anticoagulant therapy for a first episode of idiopathic venous thromboembolism to continue receiving warfarin, with the dose adjusted to achieve an international normalized ratio of 2.0 to 3.0, or to receive placebo for a further 24 months. Our goal was to determine the effects of extended anticoagulant therapy on rates of recurrent symptomatic venous thromboembolism and bleeding. RESULTS: A prespecified interim analysis of efficacy led to the early termination of the trial after 162 patients had been enrolled and followed for an average of 10 months. Of 83 patients assigned to continue to receive placebo, 17 had a recurrent episode of venous thromboembolism (27.4 percent per patient-year), as compared with 1 of 79 patients assigned to receive warfarin (1.3 percent per patient-year, P<0.001). Warfarin resulted in a 95 percent reduction in the risk of recurrent venous thromboembolism (95 percent confidence interval, 63 to 99 percent). Three patients assigned to the warfarin group had nonfatal major bleeding (two had gastrointestinal bleeding and one genitourinary bleeding), as compared with none of those assigned to the placebo group (3.8 vs. 0 percent per patient-year, P=0.09). CONCLUSIONS: Patients with a first episode of idiopathic venous thromboembolism should be treated with anticoagulant agents for longer than three months.  相似文献   
114.
Seventy-six patients were interviewed within a week of admission following a parasuicide episode. Axis II diagnosis on DSM-III was made for schizotypal, borderline, histrionic, and antisocial personality disorder. In addition patients completed a self-rating questionnaire, the Schizotypy Questionnaire of Claridge & Broks (1984), which assesses schizotypal and borderline personality traits. The objective and subjective indices of schizotypal and borderline symptoms correlated significantly but allocation of patients to a diagnosis missed several patients who nevertheless rated themselves as having a high frequency of these symptoms. There was an asymmetry of symptom pattern reminiscent of Foulds & Bedford's (1975) hierarchy model. The presence of schizotypal symptoms appeared to be higher in the hierarchy: they predicted borderline symptoms, but a high frequency of borderline symptoms did not necessarily predict schizotypy. We suggest that the occurrence of schizotypal symptoms should become a more explicit focus of clinical assessment and treatment of these patients, especially those who repeatedly harm themselves and we suggest ways in which cognitive therapies may be adapted to do this.  相似文献   
115.
Normal hyperplastic and malignant endometrial specimens were labelled in vitro with bromodeoxyuridine (BrdU). S-phase cells were stained after DNA denaturation, using a monoclonal antibody to BrdU and an indirect immunoperoxidase method. Various conditions for BrdU uptake, DNA denaturation, and staining were tested. BrdU labelling was compared with autoradiography using tritiated thymidine, with good correlation. Glandular labelling indices of proliferative endometrium were significantly higher than both secretory and hyperplastic endometrium but were similar to carcinoma. Stromal labelling showed the same trend but the differences were not statistically significant.  相似文献   
116.
Glyoxalase enzymes I and II are involved in a detoxification process consisting of conversion of reactive dicarbonyl compounds (e.g., methylglyoxal) to less reactive hydroxy acids. The structural gene for meningococcal glyoxalase I (gloA) was identified by screening an expression library with a rabbit antiserum. The meningococcal gloA gene consisted of 138 deduced amino acids, with a calculated mol. wt of 15.7 kDa. The DNA and deduced protein sequence of gloA was compared to known sequences of glyoxalase I enzymes and showed high homology with gloA of several eukaryotic and prokaryotic species. Insertion of a gloA-containing plasmid in Escherichia coli increased the host organism's tolerance to methylglyoxal from <2 mM to >4 mM, thus demonstrating its functional identity. A databank search also revealed the presence of a putative gloB gene, encoding glyoxalase II (GlxII), in the recently released genomic sequences of Neisseria meningitidis and N. gonorrhoeae.  相似文献   
117.
The hypothesis that the prostatic plasma membrane sodium pump apparatus functions as a non-genomic androgen receptor is based upon a number of its properties: (1) Androgen enhances the uptake of K(+) into minced rat prostate. (2) Ouabain, a specific inhibitor of Na/K-ATPase activity, strongly opposes the androgenic effect. (3) In non-genomic microsomes, ouabain sensitivity of the enzyme is enhanced by androgen. (4) Kinetic studies show that androgen significantly increases Vmax, Km and energy of activation of the enzyme. (5) Enzyme, treated with [gamma-(32)P]-ATP and then subjected to SDS-PAGE electrophoresis, binds only to its alpha-subunit, but, if treated with [(3)H]-DHT, shows isotope binding to the beta-subunit. (6) [(3)H]-ouabain binding to androgenized enzyme is 5.5 times greater than to the non-androgenized enzyme. (7) Treatment of the enzyme with 10(-9) M DHT enhances by 40% the binding of the ouabain derivative, anthroyl ouabain (AO). (8) Fluorescent spectra appears to show that, upon phosphorylation of the androgenized enzyme, there is a 14% approximation of the two subunits to each other. (9) Except for neuroepithelium, only the epithelium of the prostate has apically located Na/K-ATPase. Preliminary work in other labs suggests that the beta-subunit of the Na/K-ATPase may be required for establishing the polarity of some epithelial cells.  相似文献   
118.
Intestinal inflammation affects smooth muscle contractility contributing to altered motility, but changes to the individual smooth muscle cells are not well described. We used video microscopy to study the contractility of circular smooth muscle cells (CSMC) isolated from the rat mid-descending colon throughout the course of TNBS-induced colitis, measuring their shortening response to carbachol (CCh), 5-HT, histamine or high K+. In control CSMC, CCh caused a maximal shortening response of 28 (2%), similar to that for 5-HT of 27 (1%), but by day 4 of colitis, these responses were decreased by 35% and 37%, respectively. By day 36, all aspects of cholinergic contraction returned to control levels, while 5-HT-induced contraction remained significantly attenuated. In contrast, the contractile responses to histamine remained similar at all time points. K+-induced contraction was impaired only on day 4, and the maximal response remained substantially greater than CCh or 5-HT. Colitis caused a 121% increase in CSMC length by day 2 that persisted through day 36, independent evidence for phenotypic change. We conclude that impaired CSMC contractility at both the receptor and non-receptor levels contribute to altered smooth muscle function during colitis. Persistent changes in contractile response remained detectable after resolution of inflammation, and similar events may occur in post-enteritis syndromes seen in humans.  相似文献   
119.
T cell death and transplantation tolerance   总被引:15,自引:0,他引:15  
Li XC  Strom TB  Turka LA  Wells AD 《Immunity》2001,14(4):407-416
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120.
An interactive CD-ROM program designed to reduce adolescent substance use was developed and evaluated. The program uses video vignettes to teach refusal skills and socially acceptable responses to substance use situations, specifically offers of marijuana. In a randomized pretest-to-posttest experiment with 74 public school students from six classes in three high schools, significant changes were observed at posttest on (1) the adolescent's personal efficacy to refuse the offer of marijuana, (2) the adolescent's intention to refuse marijuana if offered, and (3) the adolescent's perceptions of the social norms associated with substance use and the importance of respecting another's decision to refuse a drug offer. In addition, adolescents in the treatment condition were able to recall approximately 50% of the portrayed refusal strategies. Findings are discussed with regard to the potential benefits of an interactive multimedia approach for conducting substance use interventions.  相似文献   
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