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61.
62.
Purpose. The genetic stability of a recombinant human factor VIII (rhFVIII) product expressed in Chinese hamster ovary cells (Recombinate) has been evaluated through comparisons of the protein produced at the beginning, middle and end of a typical production campaign.
Methods. Recombinant human factor VIII was incubated with thrombin, the resulting four polypeptides were isolated by RP-HPLC, subjected to proteolysis with trypsin, and the peptide mixtures were resolved by RP-HPLC. Tryptic peptide mixtures were subjected to online mass spectrometric analysis using an electrospray ionization source interfaced to a quadrupole mass analyzer scanning from 1950–200 amu, and the peptide ion data were compared for three lots produced from the beginning, middle and end of a production campaign.
Results. The UV elution profiles for each of the rhFVIIIa polypeptides were highly similar for factor VIII isolated from the beginning, middle and end of production. Total ion data from the peptide maps derived from three lots of rhFVIII were compared by MH1+ values as a function of scan range. A total of 918 ions were analyzed for the four polypeptides of rhFVIII produced at the beginning, middle and end of a production campaign. The ions were detected at the same relative retention times, as indicated by the similar scan numbers for the three lots.
Conclusions. These observations support that rhFVIII preparations produced from the beginning, middle and end of a production campaign were highly similar, and demonstrate genetic stability in the manufacturing process of Recombinate. 相似文献
63.
Pulmonary venous flow as assessed by Doppler echocardiography: potential clinical applications 总被引:2,自引:0,他引:2
During the past few years Doppler assessment of pulmonary venous flow has gained increasing interest. The growing experience with the use of transesophageal echocardiography, the approach that nearly always yields registrations adequate for quantitative analysis, has markedly contributed in this respect. The Doppler-derived pulmonary venous flow pattern can be regarded as a measure of left atrial inflow and it augments the clinical significance of Doppler transmitral flow in the evaluation of diastolic left ventricular function. This article summarizes physiological background, possible applications, and limitations of Doppler echocardiography of pulmonary venous flow in clinical cardiology. 相似文献
64.
Echocardiographic determination of left ventricular mass provides prognostic information that is independent of blood pressure. This prognostic information has a graded and continuous relationship with outcome, and is independent of traditional risk factors. This article addresses the prognostic and clinical utility of echocardiography for detection of left ventricular mass. Recommendations will be offered regarding the use of echocardiography for screening in select individuals. 相似文献
65.
66.
Joel M. Childers MD Amir Nasseri MD Earl A. Surwit MD 《American journal of obstetrics and gynecology》1996,175(6):1451-1459
OBJECTIVE: Our aim was to evaluate the feasibility and applicability of operative laparoscopy in the management of adnexal masses that do not meet the standard serum CA 125 and ultrasonographic criteria for benignity. STUDY DESIGN: One hundred thirty-eight patients underwent operative laparoscopy for removal of suspicious adnexal masses. The CA 125 level was >35 mIU/ml in 39 of 138 (28%) patients; ultrasonographic findings were abnormal in 127 of 138 (92%); masses were >10 cm in 43 of 138 (32%) of patients. RESULTS: Malignancies were discovered in 14% (19/138) of patients. Eight percent (11/138) of the procedures were converted to laparotomy, six because of inability to dissect the mass laparoscopically and five for staging or debulking of carcinoma. Operative times ranged from 25 to 210 minutes, with a mean of 86. Three major complications were encountered-an enterotomy and a lacerated vena cava, both of which were repaired laparoscopically, and a small bowel herniation through a lateral port site that required reoperation. Hospital stays ranged from 0 to 11 days, with a mean of 1.5. In two patients with "apparent" stage I adnexal carcinomas recurrence was diagnosed 6 and 38 months after surgery. CONCLUSIONS: Laparoscopic management of suspicious adnexal masses is technically feasible, with a low rate of morbidity and a short hospital stay. Adnexal carcinomas can be identified and managed appropriately with staging and complete resection as indicated. (Am J Obstet Gynecol 1996;175:1451-9.) 相似文献
67.
BACKGROUND.: Oedema formation in the nephrotic syndrome is primarily dueto tubular sodium retention. The pathogenetic role of alphaatrial natriuretic peptide (ANP), a hormonal promoter of natriuresisis unknown. METHODS.: In 31 patients (aged 35±11 years) with nephrotic syndromeand histopathological evidence of primary glomerulonephritis,we investigated plasma ANP concentration and its influence onrenal haemodynamics, natriuresis, and proteinuria (total protein,albumin, IgG excretion). Patients with a compensated treatedform of nephrotic syndrome due to primary glomerulonephritiswere included in the study. Serum creatinine levels were 1.4mg/dl. Diuretic medication was discontinued at least 24 h beforethe investigation was started. Patients were randomly assignedto ANP infusion (0.005 µg/kg*min; group II, n=15) or receivedplacebo (group III, n=16). Ten healthy subjects (group I) servedas normal controls. RESULTS.: In normal subjects (group I), ANP caused an increase in natriuresisfrom 14.5±4.2mmol/h to 26.4±11.1 mmol/h (P<0.01).In patients with nephrotic syndrome (group II), baseline sodiumexcretion of 10.5±6.0 mmol/h was increased to 19.6±14.8mmol/h with ANP infusion (P<0.01). No changes were seen inthe placebo group III. The absolute increase in ANP inducednatriuresis was not significantly different between group Iand II. However, plasma ANP levels were significantly higherin patients with nephrotic syndrome (166±87 pg/ml vs.74±21 pg/ml, P<0.05) and also reached higher levelsafter ANP infusion (P<0.01). Therefore, natriuresis was significantlyreduced when circulating ANP levels were taken into account(P<0.05). ANP administration resulted in an increase of totalprotein excretion in patients with the nephrotic syndrome (groupII, from 219±277 mg/h to 264±268 mg/h). Albuminelimination rose from 128±151 mg/h to 167±170mg/h (P<0.05) and IgG excretion from 4.91±6.67mg/hto 9.27±10.78mg/h (P<0.05). Healthy subjects alsoshowed a small but significant increase in albuminuria (48±38%,P<0.05). Low-dose ANP infusion did not, however, induce anysignificant alteration in GFR, ERPF and blood pressure. CONCLUSION.: ANP plasma concentrations in the steady state are elevated inpatients with the nephrotic syndrome. The natriuretic effectof ANP is reduced when referring to circulating ANP plasma levels.Elevated ANP levels enhance urinary protein excretion in thenephrotic syndrome. This is not due to modulation of GFR orFF, but is most probably attributable to increased glomerularpermeability. 相似文献
68.
目的 探讨P波离散度 (Pd)对急性心肌梗死并发房颤的预测价值。 方法 选 36例急性心肌梗死并发房颤的患者 ,观察其P波离散度 ,P波最大时限 (Pmax)。选 80例单纯急性心肌梗死的患者 ,作对照分析。 结果 急性心肌梗死并发房颤的Pd、Pmax与对照组比较有明显差异 (P <0 .0 1)。 结论 P波离散度可作为急性心肌梗死患者并发房颤的一预测指标。 相似文献
69.
70.
Serap Karasalholu Naci Öner Galip Ekuklu Ülfet Vatansever Özer Pala 《Pediatrics international》2003,45(4):452-457
BACKGROUND: Body mass index (BMI) is the simplest way to measure obesity; therefore, it is chosen by many authorities as a screening method for adolescent obesity. Body mass index is positively correlated with the complications of childhood and adolescent obesity, such as hypercholesterolemia, insulin resistance, hyper-tension and long-term development of cardiovascular diseases. The aim of the present study was to produce percentile curves for bodyweight, height and BMI in a representative sample of adolescent girls living in urban and rural areas of Edirne, Turkey, and to compare these percentile curves with curves from other countries. METHODS: The present study was a cross-sectional study, including a representative sample of 1687 adolescent girls from rural and urban areas of Edirne, who were evaluated between May and July 2001. Bodyweight and height were measured using standard procedures. Body mass index (kg/m2) was calculated as the ratio of bodyweight to body height squared. Smoothed percentiles for these variables were calculated using polynominal regression models. Crude weight, height and BMI percentile values, as well as smoothed percentile curves are presented. RESULTS: Body mass index, weight and height reference curves for adolescent girls were produced. When we compared the BMI values of subjects in the present study with those of other countries, 85th and 95th percentiles of BMI in the present study were found to be generally lower than those for other ethnicities. CONCLUSION: Our findings show ethnic differences in BMI among adolescent girls. It will be usefull for each country to produce its own BMI percentiles. 相似文献