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991.
Background: The Doppler-derived myocardial performance index (MPI) has been used in the evaluation of left ventricular (LV) function in several diseases. In patients with isolated diastolic dysfunction, the diagnostic utility of this index remains unclear. The aim of this study was to determine the diagnostic utility of MPI in patients with systemic hypertension, impaired LV relaxation, and normal ejection fraction. Methods: Thirty hypertensive patients with impaired LV relaxation were compared to 30 control subjects. MPI and its components, isovolumetric relaxation time (IRT), isovolumetric contraction time (ICT), and the ejection time (ET), were measured from LV outflow and mitral inflow Doppler velocity profiles. Results: MPI was higher in patients than in control subjects (0.45 ± 0.13 vs 0.37 ± 0.07 P < 0.0029). The increase in MPI was due to the prolongation of IRT without significant change of ICT and ET. MPI cutoff value of ≥0.40 identified impaired LV relaxation with a sensitivity of 63% and specificity of 70% while an IRT >94 ms had a sensitivity of 67% and specificity of 80%. Multivariate analysis identified relative wall thickness, mitral early filling wave velocity (E), and systolic myocardial velocity (Sm) as independent predictors of MPI in patients with hypertension. Conclusions: MPI was increase in patients with hypertension, diastolic dysfunction, and normal ejection fraction but was not superior to IRT to detect impaired LV relaxation.  相似文献   
992.
Myostatin inhibitors are being investigated as treatments for myopathies. We assessed single muscle fiber contractile properties before and after 6 months of study drug in 6 patients with facioscapulohumeral, Becker, and limb‐girdle muscular dystrophy. Five of the patients received MYO‐029, a myostatin inhibitor, and 1 received placebo. The chemically skinned single muscle fiber preparation was used to measure single fiber force, specific force, maximum unloaded shortening velocity, power, and specific power in type I and IIa fibers from each subject. In 4 of 5 patients who received MYO‐029, improvement was seen in single muscle fiber contractile properties; thus, there may be a beneficial effect of myostatin inhibition on muscle physiology at the cellular level. No improvement was seen in the patient who received placebo. This finding may be clinically relevant in spite of the fact that quantitative muscle strength measurements in our patients did not improve. Further studies of myostatin inhibition as a treatment for muscular dystrophy are warranted, and single muscle fiber contractile studies are a useful assay for muscle function at the cellular level. Muscle Nerve 39: 3–9, 2009  相似文献   
993.
To develop a more appropriate therapeutic strategy for treatment of nonpulmonary visceral metastatic testicular seminoma based on the International Germ Cell Consensus Classification, we reviewed the medical records of patients with nonpulmonary visceral metastatic testicular seminoma who were treated over a 20-year period. Only 15 (2.2%) of the 686 cases of testicular seminoma were nonpulmonary visceral metastatic seminoma. The median age of patients was 38 years (range, 22-53 years). Ten (67%) of the patients had an initial diagnosis of supradiaphragmatic or visceral metastatic disease. In addition to nonpulmonary visceral metastasis, all patients had lymph node metastasis as well, the majority of which involved the retroperitoneal lymph nodes. The median and mean progression-free survival durations after chemotherapy for advanced disease were 19 months and 63.7 months, respectively. Six patients (40%) survived, five relapsed after radiation therapy and four died of chemorefractory disease not dependent on the specific regimen. Although the number of cases reviewed in this study was small, we conclude that the choice of chemotherapeutic regimen among the current treatments for nonpulmonary visceral metastatic seminoma of testis primary does not present a different outcome. Therefore, multimodality therapies using new strategies or new agents are well indicated.  相似文献   
994.
PURPOSE: The efficacy of interferon alfa has been established in treating advanced melanoma and renal cell carcinoma (RCC) patients. We conducted a phase I/II study to determine the maximum-tolerated dose (MTD), the safety and tolerability, and the preliminary efficacy of once-weekly pegylated interferon alfa-2b (IFNalpha-2b) in patients with advanced solid tumors (primarily RCC). PATIENTS AND METHODS: To determine the MTD, 35 patients with a variety of advanced solid tumors received 0.75 to 7.5 micro g/kg/wk of pegylated IFNalpha-2b by subcutaneous injection for 12 weeks. An additional 35 previously untreated RCC patients received 6.0 and 7.5 micro g/kg/wk for up to 12 weeks. Patients with a response or stable disease after 12 weeks were eligible for the extension protocol and were treated for up to 1 year or until disease progression. RESULTS: The MTD for pegylated IFNalpha-2b at 12 weeks was 6.0 micro g/kg/wk. One year of 6.0 micro g/kg/wk was well tolerated with appropriate dose modification; no grade 3 or 4 fatigue occurred, and safety was comparable with that with nonpegylated IFNalpha-2b. The most common nonhematologic adverse events included mild to moderate nausea, anorexia, and fatigue. Six patients had grade 3 or 4 hematologic toxicity. Twenty-nine patients continued on the extension protocol. Four patients had a complete response, and five patients had a partial response. Among 44 previously untreated RCC patients, the objective response rate was 14%. Median survival for all RCC patients was 13.2 months. CONCLUSION: Pegylated IFNalpha-2b was active and well tolerated in patients with metastatic solid tumors, including RCC, at doses up to 6.0 micro g/kg/wk.  相似文献   
995.
996.
The authors retrospectively review 331 cases of necrotizing enterocolitis from 13 different departments of pediatric surgery; 184 cases were treated only medically at the acute stage (47 of whom developed intestinal stricture) and 147 cases were operated on at the acute stage. The different procedures of acute surgical intervention are reported and the results of two surgical procedures are compared. The first is a classical one comprising a laparotomy with exploration of the intestinal tract and resection of the necrotic segments followed by enterostomy above the resected area. The other procedure comprises a minimal laparotomy in the right lower quadrant with ileostomy above necrotic areas, without resection of necrotic segments associated with peritoneal drainage. The results are assessed using the postoperative mortality rate and the number of secondary intestinal strictures. Mortality during the first postoperative month occurred in 27.9% of cases, and intestinal strictures were noted in 31.3% of cases after acute surgical procedure.  相似文献   
997.
Using heteroduplex analysis generated with synthetic PCR-amplifiable DNA we have screened the PKU populations of southwest England and Wales, western Scotland, and southeast and central England for mutations in exons 3, 7 and 12 of the phenylalanine hydroxylase (PAH) gene. The technique characterized three mutations in exon 12, two in exon 3 and five in exon 7. Altogether over 370 PKU chromosomes were screened. In all geographical regions exon 12 mutations (R408W, IVS12ntlg- > a and Y414C) accounted for about 40% of mutant chromosomes. Exon 3 mutations (principally I65T) were found on between 9 and 12% of mutant alleles and exon 7 mutations accounted for a further 5-7%. Heteroduplex analysis is rapid, simple and safe and three constructs covering three exons can identify between 55 and 60% of mutations in various PKU populations of the UK.  相似文献   
998.
Cytochrome P450 (CYP) enzymes of nasal tissue are relatively resistant to induction by classical inducers. In the present study, the effects of starvation on the expression of CYP1A, 2A, 2B, 2C, 2E, 2G, and 3A subfamilies in the nasal mucosa of rat were studied. Fasting for 72 hr caused an increase in 2E1-dependent p-nitrophenol hydroxylase and 1A-dependent ethoxy- (or methoxy) resorufin dealkylase activities, but did not affect either 2A-linked coumarin hydroxylase or the testosterone hydroxylase activity, the latter reaction being a marker of several CYPs including 2G1. Whereas increases in 2E1- and 1A- associated catalytic activities were accompanied by a concomitant increase in the corresponding apoproteins as determined by immunoblotting, immunoactive protein bands reactive with antibodies raised against rat 1A1, 2B1, 2C11, 3A1 or rabbit nasal 2A10/11 and 2G1 were not altered. Fasting also increased CYP2E1 and CYP1A2 on the mRNA level, but did not alter CYP1A1 mRNA as determined by hybridization with cDNA probes selective for these cytochromes. A reiterative administration of chlormethiazole, a specific inhibitor of 2E1 in liver, strongly inhibited many CYPs, including 2E1, 1A2, 2G1, and 2A in the nasal mucosa, but did not influence expression of 2B or 3A as determined by immunoblotting or catalytic activities. The chlormethiazole-mediated inhibition of 1A1 and 2E1 was demonstrated to be at the mRNA level. These results suggest that fasting induces the gene expression of 2E1 and 1A2 and that the mechanisms involved in the regulation of CYPs in the nasal mucosa are tissue-specific. The inducibility of the above-mentioned isoforms may have a significant role in the clearance of drugs and bioactivation of inhaled compounds.  相似文献   
999.
R Stephen  S Amato 《Paediatrician》1978,7(4-5):152-165
Genetic emergencies like other medical emergencies require immediate intervention to alter the outcome of the condition in the patient and its effect upon the family. The representative conditions of myelomeningocele, Down's syndrome, cleft lip and palate and adrenogenital syndrome serve to illustrate the need for rapid and comprehensive intervention. Recognition that an emergency exists when a child with a birth defect is born and responsive thoughtful action including family counseling can significantly alter the life of the patient and his family.  相似文献   
1000.
A case of non-functioning parathyroid cyst is reported, in which the preoperative diagnosis was missed. A careful review of the pertinent literature allows to outline the correct approach to this rare pathology as for the diagnosis and the treatment; as well, to enlight the current controversies about the physiopathology and the pathology.  相似文献   
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