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91.
92.
The relationship between fecundability and month of birth was investigated in a cohort of 1526 women who married between 1802 and 1929, using only women whose first marriage occurred before the age of 35 years. On the basis of their time to pregnancy (TTP, calculated as time between wedding and first birth minus gestational length), women were categorized into two groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348) and subfecunds (TTP >18 months, n = 118). By use of logistic regression, cosinor functions with a period of 1 year or 6 months and variable shift and amplitude were fitted through the monthly odds of subfecunds versus fecunds. The best fitting curve was unimodal, with a zenith in September (P = 0.13 for H0: no differences). Exclusion of childless women (n = 36, minimum follow-up 5 years) from the subfecunds led to a similar curve (P < 0.01), while childless women, as compared with fecunds, showed a birth distribution that was best represented with a bimodal curve with zeniths in January and July (P = 0.06). This study provides evidence for the existence of differences in fecundability by month of birth. The cause of this relationship is unclear, but may lie in a melatonin-dependent circannual variability of the quality of the oocyte.   相似文献   
93.
Koo JS, Shin E, Hong SW. Immunohistochemical characteristics of diffuse sclerosing variant of papillary carcinoma: comparison with conventional papillary carcinoma. APMIS 2010; 118: 744–52. Diffuse sclerosing variant of papillary carcinoma (DSVPC) is a rare variant of papillary thyroid carcinoma (PTC). It shows different clinicopathologic features to the conventional PTC, but the immunohistochemical characteristics of DSVPC are yet to be more clearly defined. The purpose of this study was to investigate the immunohistochemical features of DSVPC, which are different from those of PTC. Tissue microarray was constructed from the paraffin‐embedded tissue of 49 DSVPC and 50 conventional PTC samples. Immunohistochemical stains for p63, p53, galectin‐3, cytokeratin 19, β‐catenin, Bcl‐2, EMA, E‐cadherin, CD15, and CD56 were performed on each tissue microarray. Immunohistochemical stain for p63 was negative in all conventional PTCs, but 14 (28.6%) cases of DSVPC showed p63 expression (p = 0.000). p53 was expressed in 38 (76.0%) cases of conventional PTC and 21 (42.9%) cases of DSVPC (p = 0.001). Galectin‐3 was expressed in all 50 cases of conventional PTC, but eight (16.3%) cases of DSVPC did not express galectin‐3 (p = 0.003). EMA was expressed more in DSVPC (40.8%) than in conventional PTC (20.0%, p = 0.024). In univariate analyses, Bcl‐2 positivity (p = 0.016) and EMA negativity (p = 0.036) in DSVPC were associated with shorter time interval to tumor recurrence, but there was no significance for the two in multivariate analyses. DSVPC, a rare variant of PTC, has different immunohistochemical features from the conventional PTC, showing higher expression rate of p63 and lower expression rate of p53. It also shows galectin‐3 negativity and EMA positivity.  相似文献   
94.
95.
Securinega virosa is used traditionally as sedative in children and in mental illnesses. In this study, the behavioral effects of methanolic root bark extract of S. virosa were investigated in mice. The results revealed that the extract significantly (P<0.05) and dose-dependently reduced the onset and prolonged the duration of sleep. The extract significantly (P<0.05) decreased exploratory activity and reduced the rate of apomorphine-induced stereotyped climbing at the doses tested (6.25–25mg/kg). It also produced a significant and dose-dependent motor coordination deficit in mice at the doses tested (P<0.01). The intraperitoneal median lethal dose in mice was 774.6mg/kg while the preliminary phytochemical screening revealed the presence of alkaloids, tannins, saponins and flavonoids. These results suggest that methanolic root bark extract of S. virosa contains biologically active principles that are sedative in nature and lend pharmacological credence to the ethnomedical use of the plant.  相似文献   
96.
Neuroblastoma risk stratification is based on stage, age, and biology and prescribes surgery for low-risk disease, moderate-dose chemotherapy for intermediate-risk disease, and maximal therapy (including myeloablative treatment with stem cell transplantation) for high-risk disease. Four cases are described that depict pitfalls in risk assessment with potentially far-reaching consequences. This report focuses on a subset of four patients referred for second opinions. Stage was defined by the International Neuroblastoma Staging System. The first recommendations were for maximal therapy, but second opinions were radically different (ie, surgery alone). Ages at diagnosis were 15 to 25 months. Shimada histopathology was unfavorable in three of the four patients, but chromosomal, serum, and urine prognostic markers were favorable. All four patients did well without cytotoxic therapy (follow-up: 2 years 10 months plus to 4 years 8 months plus). Patient 1 had abdominal and upper thoracic/supraclavicular masses (stage 4); the former was resected and the latter spontaneously regressed. Patient 2 had retroperitoneal disease, without bone marrow involvement, but imaging studies showed lesions in vertebral bodies. Biopsies of the latter showed no neuroblastoma and the primary tumor (with regional lymph nodes) was resected, changing stage from 4 to 2B. Patient 3 had a retroperitoneal mass but no distant disease. Though initially deemed to be unresectable, the abdominal tumor was excised, changing the classification from high risk (stage 3 with unfavorable histopathology) to low risk (stage 1). Patient 4 had a pelvic mass, with unfavorable histopathology, and bilateral inguinal lymph node involvement (stage 3); all soft tissue disease was resected. The absence of cortical bone and extensive bone marrow metastatic involvement in a young neuroblastoma patient should cause a shift in attention to biologic prognostic markers. Some patients classified as having high-risk neuroblastoma might actually do well with no cytotoxic therapy.  相似文献   
97.
OBJECTIVE: Results of the ICON4/AGO-OVAR-2.2 trial suggest that a platinum/taxane combination provides a survival benefit in relapsed, platinum-sensitive ovarian cancer compared to platinum alone. The optimal specific combination has yet to be determined. The current study evaluates weekly docetaxel and carboplatin in this setting. METHODS: Using a prospective phase II design, patients received weekly docetaxel (35 mg/m2) and carboplatin (AUC=2) administered days 1, 8, and 15 of a 28-day cycle. Initial treatment with a platinum-based regimen was required, with a treatment-free interval of at least 3 months. Patients could have received one prior regimen for recurrence. Biologically evaluable disease (CA-125) could be followed only if measurable disease was not present. Quality of life analysis utilized the FACT-O and FACT/GOG-Ntx scales. RESULTS: Thirty-six patients enrolled in the trial over 29 months. The majority had ovarian cancer (89%) and stage III/IV (97%) disease, with a median initial disease-free interval of 12 months. Most subjects were treated for first recurrence (81%) and had measurable disease (58%). The overall response rate was 67% (PR=52%, CR=15%), with 22% stable disease. Grade 3/4 neutropenia was common (48%) while serious anemia and thrombocytopenia were not. Neuropathy was generally mild and manageable. Carboplatin hypersensitivity led to 11 subjects coming off trial (31%). Diphenhydramine premedication produced a nonsignificant decrease in reaction rate. There was no detectable difference in quality of life due to therapy. CONCLUSION: The weekly regimen of carboplatin and docetaxel has a good response rate with an acceptable toxicity profile.  相似文献   
98.
Hereditary haemochromatosis (HFE) is a common inherited disorder, affecting approximately five per thousand white people of northern European descent. Genetic linkage and linkage disequilibrium studies indicate that the disease locus is tightly linked to HLA-A and D6S105. Recombination between HFE and HLA class I loci is known to be rare. We report here two pedigrees in which recombinations telomeric of HLA-A occurred. These recombinant events define new centromeric and telomeric borders for the HFE locus.  相似文献   
99.
Infected pancreatic fluid collections: percutaneous catheter drainage   总被引:5,自引:0,他引:5  
Freeny  PC; Lewis  GP; Traverso  LW; Ryan  JA 《Radiology》1988,167(2):435-441
Thirty-eight infected pancreatic fluid collections in 23 patients with acute or chronic pancreatitis were drained percutaneously following initial diagnosis with computed tomography and fine-needle aspiration. Fifteen (65.2%) patients were cured completely without surgery. Eight (34.8%) patients required some type of surgery despite successful treatment of the fluid collection, and in two (6.5%) the collection recurred after catheter removal. Complications occurred in three (13%) patients, but only one complication (4%), empyema, was a direct result of catheter drainage. Catheter drainage time averaged 29 days for 16 patients with isolated collections and 96 days and 104 days for patients with collections with pancreatic duct fistulas (nine patients) or gastrointestinal fistulas (14 patients), respectively. This study confirms that infected pancreatic fluid collections can be safely and effectively treated with percutaneous catheter techniques in most patients.  相似文献   
100.
Glycogen storage disease due to phosphorylase kinase deficiency occurs in several variants that differ in mode of inheritance and tissue- specificity. This heterogeneity is suspected to be largely due to mutations affecting different subunits and isoforms of phosphorylase kinase. The gene of the ubiquitously expressed beta subunit, PHKB, was a candidate for involvement in autosomally transmitted phosphorylase kinase deficiency of liver and muscle. To identify such mutations, the complete PHKB coding sequence was amplified by RT-PCR of RNA isolated from blood samples of patients and analyzed by direct sequencing of PCR products. The characterization of mutations was complemented by PCR of genomic DNA. In one female and four male patients, we identified five independent nonsense mutations (Y418ter; R428ter; Y974H+E975ter; Q656ter in two cases), one single-base insertion in codon N421, one splice-site mutation affecting exon 31, and a large deletion involving the loss of exon 8. Although these severe translation-disrupting mutations occur in constitutively expressed sequences of the only known beta subunit gene of phosphorylase kinase, PHKB, they are associated with a surprisingly mild clinical phenotype, affecting virtually only the liver, and relatively high residual enzyme activity of approximately 10%.   相似文献   
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