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101.
Rats were treated with 17 alpha-ethinyl estradiol to induce high levels of low-density lipoprotein receptors in hepatocytes. When these rats were given intravenous injections of low-density lipoprotein-colloidal gold complexes, most of the gold (labeled with 195Au) appeared to be taken up by Kupffer cells, as were complexes of colloidal gold with albumin or polyvinylpyrrolidone. However, when these rats were also administered gadolinium chloride, which blocks Kupffer cell activity, most of the low-density lipoprotein-gold (but not gold complexed with albumin or polyvinylpyrrolidone) was taken up into hepatocytes by receptor-mediated endocytosis and concentrated in peribiliary lysosomes, as determined by electron microscopy. Colloidal gold taken up as a complex with low-density lipoprotein was excreted into the feces via the common bile duct at a maximal rate of about 5% daily, 4 to 12 days after injection. Thereafter, the rate of gold excretion fell off until reaching a plateau after 3 weeks. At this late time, most of the colloidal gold was shown by electron microscopy to be in Kupffer cells, whereas earlier (6 days after injection) it was contained mainly in older hepatocytic lysosomes, identified by lipofuscin granules. It is concluded that, in rats, hepatocytic lysosomes empty most of their contents into bile every week or two, apparently by exocytosis.  相似文献   
102.
Chronic myelogenous leukemia (CML) is caused by expression of the BCR-ABL tyrosine kinase oncogene, the product of the t(9;22) Philadelphia translocation. Patients with CML in accelerated phase have rapidly progressive disease and are characteristically unresponsive to existing therapies. Imatinib (formerly STI571) is a rationally developed, orally administered inhibitor of the Bcr-Abl kinase. A total of 235 CML patients were enrolled in this study, of whom 181 had a confirmed diagnosis of accelerated phase. Patients were treated with imatinib at 400 or 600 mg/d and were evaluated for hematologic and cytogenetic response, time to progression, survival, and toxicity. Imatinib induced hematologic response in 82% of patients and sustained hematologic responses lasting at least 4 weeks in 69% (complete in 34%). The rate of major cytogenetic response was 24% (complete in 17%). Estimated 12-month progression-free and overall survival rates were 59% and 74%, respectively. Nonhematologic toxicity was usually mild or moderate, and hematologic toxicity was manageable. In comparison to 400 mg, imatinib doses of 600 mg/d led to more cytogenetic responses (28% compared to 16%), longer duration of response (79% compared to 57% at 12 months), time to disease progression (67% compared to 44% at 12 months), and overall survival (78% compared to 65% at 12 months), with no clinically relevant increase in toxicity. Orally administered imatinib is an effective and well-tolerated treatment for patients with CML in accelerated phase. A daily dose of 600 mg is more effective than 400 mg, with similar toxicity.  相似文献   
103.
OBJECTIVE: The purpose of this study was to evaluate the prevalence of urinary symptoms at long-term follow-up after vaginal hysterectomy. STUDY DESIGN: One hundred and seventeen patients, who had a vaginal hysterectomy for menorrhagia, from January 1991 to December 2001, answered to a self-report questionnaire about de novo urinary symptoms. The control group was a population of 116 patients who had a conservative treatment for dysfunctional uterine bleeding by endometrial thermocoagulation from January 1994 to December 2001. RESULTS: Patient characteristics (mean age, mean parity, menopausal status, smoking status, drink habits) were similar in the two groups. Mean follow-up was 4.6+/-2.2 years (range 1.5-11) after vaginal hysterectomy and 4+/-1.8 years (range 1.5-7) after conservative treatment. The prevalence of urinary symptoms, included urge and stress incontinence, were statistically similar in the two groups. CONCLUSION: This study reveals no risk of urge or stress urinary incontinence at long-term follow-up after vaginal hysterectomy, compared with conservative treatment.  相似文献   
104.
In February 2021, an explosion of cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia overwhelmed the only hospital in Mayotte. To report a case series of patients with acute respiratory failure (ARF) due to SARS-CoV-2 who were evacuated by air from Mayotte to Reunion Island.This retrospective observational study evaluated all consecutive patients with ARF due to SARS-CoV-2 who were evacuated by air from Mayotte Hospital to the intensive care unit (ICU) of Félix Guyon University Hospital in Reunion Island between February 2, and March 5, 2021.A total of 43 patients with SARS-CoV-2 pneumonia were evacuated by air, for a total flight time of 2 hours and a total travel time of 6 hours. Of these, 38 patients (88.4%) with a median age of 55 (46–65) years presented with ARF and were hospitalized in our ICU. Fifteen patients were screened for the SARS-CoV-2 501Y.V2 variant, all of whom tested positive. Thirteen patients (34.2%) developed an episode of severe hypoxemia during air transport, and the median paO2/FiO2 ratio was lower on ICU admission (140 [102–192] mmHg) than on departure (165 [150–200], P = .022). Factors associated with severe hypoxemia during air transport was lack of treatment with curare (P = .012) and lack of invasive mechanical ventilation (P = .003). Nine patients (23.7%) received veno-venous extracorporeal membrane oxygenation support in our ICU. Seven deaths (18.4%) occurred in hospital.Emergency air evacuation of patients with ARF due to SARS-CoV-2 was associated with severe hypoxemia but remained feasible. In cases of ARF due to SARS-CoV-2 requiring emergency air evacuation, sedated patients receiving invasive mechanical ventilation and curare should be prioritized over nonintubated patients. It is noteworthy that patients with SARS-CoV-2 pneumonia related to the 501Y.V2 variant were very severe despite their young age.  相似文献   
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Rodent models harboring a simple yet functional human intestinal microbiota provide a valuable tool to study the relationships between mammals and their bacterial inhabitants. In this study, we aimed to develop a simplified gnotobiotic mouse model containing 10 easy-to-grow bacteria, readily available from culture repositories, and of known genome sequence, that overall reflect the dominant commensal bacterial makeup found in adult human feces. We observed that merely inoculating a mix of fresh bacterial cultures into ex-germ free mice did not guarantee a successful intestinal colonization of the entire bacterial set, as mice inoculated simultaneously with all strains only harbored 3 after 21 d. Therefore, several inoculation procedures were tested and levels of individual strains were quantified using molecular tools. Best results were obtained by inoculating single bacterial strains into individual animals followed by an interval of two weeks before allowing the animals to socialize to exchange their commensal microbes. Through this procedure, animals were colonized with almost the complete bacterial set (9/10). Differences in the intestinal composition were also reflected in the urine and plasma metabolic profiles, where changes in lipids, SCFA, and amino acids were observed. We conclude that adaptation of bacterial strains to the host's gut environment (mono-colonization) may predict a successful establishment of a more complex microbiota in rodents.  相似文献   
109.
Exocrine pancreatic insufficiency (EPI) is rare in children, with most if not all cases occurring as part of syndromic conditions such as cystic fibrosis and Shwachman–Diamond syndrome. Here we report two cases, both presenting with severe EPI around 5 months of age. Characterized by diffuse pancreatic lipomatosis, they otherwise exhibited no remarkable deficiencies in other organs. Novel non‐identical homozygous variants (a deletion removing the entire SPINK1 gene and an insertion of a full‐length inverted Alu element into the 3′‐untranslated region of the SPINK1 gene) resulting in the complete functional loss of the SPINK1 gene (encoding pancreatic secretory trypsin inhibitor) were identified in each patient. Having correlated our findings with current knowledge of SPINK1's role in exocrine pancreas pathophysiology, we propose that complete and partial functional losses of the SPINK1 gene are associated with quite distinct phenotypes, the former causing a new pediatric disease entity of severe infantile isolated EPI.  相似文献   
110.
The aims of this study were dual. First, to evaluate the feasibility of a sheep model as an animal model for vaginal surgery with meshes. Second, to compare host response to two low-weight polypropylene (PP) meshes, a noncoated (Soft Prolene™, Gynecare, Ethicon) and a coated mesh with an absorbable hydrophilic film (Ugytex™, Sofradim). Thirty-six 20×20 mm polypropylene meshes (18 coated and 18 noncoated) were surgically implanted by the vaginal route in 12 adult ewes. Meshes were implanted in the anterior (n=12) and the posterior vaginal compartments (n=24). Animals were killed 1 (n=6) and 12 (n=6) weeks after surgery. Postimplantation evaluation included macroscopical examination, histological and immunohistochemical analysis and histomorphometrical measures of the distance between the meshes and the vaginal epithelium. The experimental procedure was feasible in all cases. Vaginal erosions were observed twice as frequently with the noncoated-PP meshes (6/18, 33.3%) as with the coated-PP meshes (3/18, 16.7%), even if that difference was not significant (p=0.4). However, no differences were observed between the two meshes in terms of shrinkage, tissue ingrowth, inflammatory response, and position of the mesh in the vaginal wall. The mechanism involved in the reduction of vaginal erosion could be due to the lesser adhesion of the coated mesh on the vaginal wound during the early postoperative period.  相似文献   
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