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101.
The pharmacokinetics of cefpimizole (free acid equivalents of cefpimizole sodium), a broad-spectrum cephalosporin antibiotic, were evaluated after intramuscular administration of single doses (dose range, 100 to 1,000 mg) and multiple doses (dose range, 500 to 2,000 mg) given b.i.d. for 6 or 11 days. The kinetics after intramuscular administration correspond to a one-compartment model with first-order input. The apparent volume of distribution of the absorbed dose averaged 18.6 +/- 3.4 (standard deviation) liters for 58 individuals; the absorption-phase and elimination-phase rate constants averaged 2.53 +/- 1.16 h-1 (half-life, 0.27 h) and 0.338 +/- 0.041 h-1 (half-life, 2.05 h), respectively; and the mean residence time was 3.43 +/- 0.43 h. The total body clearance of the absorbed dose after single-dose intramuscular administration was 102 +/- 13 ml/min. The primary route of elimination was renal with 73 to 83% of the administered dose excreted in the urine as unchanged drug. Renal clearance averaged 81 +/- 13 ml/min. Dose proportionality was obtained from area under the plasma curve, concentration maximum in plasma, and cumulative urinary excretion levels. Multiple-dose evaluation of intramuscular administration of cefpimizole indicated no apparent change in the absorption or elimination phases after b.i.d. dosing for 6 or 11 days. The kinetic parameters determined from multiple-dose plasma and urine levels were in close agreement with the same parameters calculated from single-dose results. No apparent accumulation of cefpimizole occurred, and nondetectable levels of drug were observed in the 24-h plasma and 24- to 48-h urine specimen after administration of the last dose. The kinetics of cefpimizole after intramuscular administration were similar to the kinetics obtained after intravenous infusion.  相似文献   
102.
Gnetales comprise three unusual genera of seed plants, Ephedra, Gnetum, and Welwitschia. Their extraordinary morphological diversity suggests that they are survivors of an ancient, more diverse group. Gnetalean antiquity is also supported by fossil data. Dispersed "ephedroid" (polyplicate) pollen first appeared in the Permian >250 million years ago (Myr), and a few megafossils document the presence of gnetalean features in the early Cretaceous. The Cretaceous welwitschioid seedling Cratonia cotyledon dates the split between Gnetum and Welwitschia to before 110 Myr. Ages and character evolution of modern diversity are, however, controversial, and, based on molecular data, it has recently been suggested that Ephedra is very young, only 8-32 Myr. Here, we present data on the evolutionary history of Ephedra. Fossil seeds from Buarcos, Portugal, unequivocally link one type of Cretaceous polyplicate pollen to Ephedra and document that plants with unique characters, including the peculiar naked male gametophyte, were established already in the Early Cretaceous. Clades in our molecular phylogeny of extant species correspond to geographical regions, with African species in a basal grade/clade. The study demonstrates extremely low divergence in both molecular and morphological characters in Ephedra. Features observed in the fossils are present in all major extant clades, showing that modern species have retained unique reproductive characters for >110 million years. A recent origin of modern species of Ephedra would imply that the Cretaceous Ephedra fossils discussed here were members of widespread, now extinct sister lineage(s), and that no morphological innovations characterized the second diversification.  相似文献   
103.
The aim was to explore whether the incidence of tonsillar squamous cell carcinomas (TSCCs) increased in Eastern Denmark, 2000–2010, and whether human papillomavirus (HPV) could explain the increase, and to assess the association of HPV prevalence with gender, age, and origin (i.e., the certainty of tonsillar tumor origin). We applied HPV DNA PCR and p16 immunohistochemistry to all TSCCs registered in the Danish Head and Neck Cancer Group (DAHANCA) and in the Danish Pathology Data Bank (n = 632). Pathologists reviewed and subdivided the tumors into two groups: specified and nonspecified TSCCs. Approximately 10% of HPV‐positive tumors was genotyped by amplicon next‐generation sequencing. The overall crude incidence of TSCCs increased significantly (2.7% per year) and was explained by an increasing incidence of HPV‐positive TSCCs (4.9% per year). The overall HPV prevalence was 58%, with HPV16 being the predominant HPV type. In multivariate analysis, the HPV prevalence was associated with age (<55 vs. >60 years) (OR, 1.72; 95% CI 1.13–2.63) and origin (nonspecified vs. specified TSCCs) (OR, 0.15; 95% CI 0.11–0.22). The association of HPV prevalence with origin increased over time in specified TSCCs (OR per year, 1.10; 95% CI 1.01–1.19), whereas no change over time was observed among nonspecified TSCCs (OR per year, 0.99; 95% CI 0.90–1.08). In conclusion, the observed increase in the number of HPV‐positive TSCCs can explain the increasing number of TSCCs in Eastern Denmark, 2000–2010. HPV prevalence was associated with younger age (<55 years) and a high certainty of tonsillar tumor origin.  相似文献   
104.
We examined the prevalence of cigarette smoking among Cambodian Americans in Long Beach, California. A stratified random sample of 1,414 adult respondents was selected from 15 census tracts with high concentrations of Cambodian Americans. The prevalence of current smokers was 13.0%; the sex-specific prevalence of smoking was 24.4% for men and 5.4% for women. The mean age of the sample was 50.5 years; about 60% of the respondents were women. The survey response rate was 90.5% among households in which respondents self-identified as Cambodian American, and at least one person completed the survey. Significant covariates of current smoking were gender, age, education, marital status, and health status. The prevalence of smoking among Cambodian men was higher than among other males in California. Culturally-tailored interventions should consider demographic characteristics of the target population as well as the high level of respect given to religion, elders, and peers.  相似文献   
105.

Objective

Epstein–Barr virus (EBV) infection is an established risk factor for B-cell lymphomas in Human Immunodeficiency virus (HIV)-1 infected patients. A disturbed EBV-host relationship is seen in patient groups with a high risk for EBV-associated lymphomas. We have analysed this relationship by measuring EBV-DNA in the blood of HIV-1 carriers.

Method

EBV-DNA load in B-cells was monitored by PCR in non- or insufficiently antiretroviral treated and rgp160-vaccinated HIV-patients.

Results

Both asymptomatic HIV-infected and AIDS-patients showed a 25–40-fold increase in the number of B cell associated EBV-DNA copies compared to healthy controls. Patients included in a vaccine trial with recombinant HIV gp160 showed a 5-fold increase of EBV load compared to non-immunised patients and a 50-fold increase compared to healthy controls. There was no difference whether they received vaccine or “placebo”. Vaccinated patients with a history of symptomatic primary HIV-1 infection (PHI) had a 280-fold increase in median EBV load compared to healthy controls, thus suggesting a synergistic effect between the vaccination and PHI, which hypothetically could affect lymphoma risk.

Conclusions

We recommend analysis of EBV-load and long term follow up of lymphoma risk in all therapeutic HIV-1 vaccination trials.  相似文献   
106.
107.
The aim of this study was to examine self-reported symptomatology and to identify distinctive characteristics among women with silicone breast implants (SBI). Using the Danish hospital and population registers we identified three groups of women with a hospital diagnosis of muscular rheumatism (a non-specific soft-tissue diagnostic code) who had previously undergone SBI surgery (n= 28), breast reduction surgery (n= 29) or no breast surgery (n= 27); and three groups of women without a diagnosis of muscular rheumatism who had undergone SBI surgery (n= 21), breast reduction surgery (n= 27) or no breast surgery (n= 56). All study subjects completed a self-administered questionnaire focusing on sociodemographic factors, lifestyle habits, somatic symptoms and psychological symptoms. Women with SBI and women with breast reduction with no previous diagnosis of muscular rheumatism had similar patterns of reporting for most symptoms and characteristics. They reported significantly more somatic symptoms and psychological distress, including somatisation, obsessive–compulsiveness and depression, than women with no breast surgery. No significant differences in self-reported symptomatology and characteristics were observed among the three groups of women with a previous diagnosis of muscular rheumatism. Overall, women with prior muscular rheumatism reported more symptoms than those without. We concluded that self-reported somatic symptoms among women with SBI were similar to those of controls. Women with cosmetic breast surgery appear to have distinctive psychological characteristics. Our study emphasises the importance of taking the psychological profile and previous history of rheumatic diseases into account when examining women with SBI. Received: 28 February 2001 / Accepted: 2 July 2001  相似文献   
108.
The extrathyroidal metabolism of T4, T3, rT3, and 3',5'-diiodothyronine (3',5'-T2) was studied before and after treatment with 350 mg phenytoin (DPH) daily for 14 days in six hypothyroid patients receiving constant L-T4 replacement. The total and free serum concentrations of the four iodothyronines were reduced by approximately 30% during DPH treatment, whereas the free fractions in serum were unaltered. Concomitantly, serum TSH increased 137% (P less than 0.02). The production rate (PR) of T4 decreased 16% (P less than 0.005), indicating decreased intestinal absorption (bioavailability) of oral L-T4 during DPH treatment. The fractional rate of 5'-deiodination of T4 to T3 increased from 27% to 31% (P less than 0.05), whereas the rate of 5-deiodination of T4 to rT3 decreased from 45% to 25% (P less than 0.05). The urinary excretion of free and conjugated T4 was 2.3% of the T4 PR and was unaffected by DPH. Thus, the amount of T4 metabolized through nondeiodinative pathways apart from urinary excretion increased from 25% to 44% (P less than 0.05). The apparent distribution volume (Vd) of T4 increased (P less than 0.05), whereas the pool size was unchanged. The PR of T3 did not change during DPH treatment, nor did the mean transit time or the cellular clearance. The rT3 PR was reduced by 54% (P less than 0.02) during DPH treatment. Concomitantly, the transit time increased 10-fold (P less than 0.05), whereas Vd and pool size increased 5-fold (P less than 0.01 and P less than 0.05, respectively). The turnover of 3',5'-T2, in contrast to that of the other iodothyronines, did not change significantly during DPH treatment. T3 formation from T4 was measured in liver microsomal fractions from rats treated for 8 days with DPH and was almost identical to that in untreated animals. The data demonstrate that DPH in therapeutic concentrations did not affect serum protein binding of the iodothyronines. DPH reduced the intestinal absorption of T4 and increased the nondeiodinative metabolism of T4. The resulting decrease in total and free serum T4 and T3 was associated with an increase in serum TSH, demonstrating reduced negative feedback on the pituitary. Our data do not support the assumption that DPH induces increased hepatic deiodinating enzyme activity.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
109.
In this study, we tested the first commercial kit with insertion/deletion (indel) polymorphisms, the Mentype(?) DIPplex PCR Amplification Kit (DIPplex kit). A total of 30 biallelic autosomal indels and Amelogenin were amplified with the DIPplex kit. All loci were amplified in one PCR multiplex and all amplicon lengths were shorter than 160 bp. Full indel profiles were generated from as little as 100 pg of DNA. A total of 117 individuals from Danish paternity cases were successfully typed. No deviation from Hardy-Weinberg equilibrium was observed for any of the indels. The combined mean match probability was 3.3 × 10(-13), the mean paternity exclusion probability was 99.7% and the typical paternity indices for trios and duos were 2350 and 165, respectively. Furthermore, we typed five highly degraded DNA samples with the DIPplex kit, the AmpFlSTR(?) SGM Plus kit and the AmpFlSTR(?) SEfiler Plus kit. Full indel profiles were obtained with the DIPplex kit, whereas only partial profiles were obtained with the STR kits. In general, the DIPplex kit performed well and it would be a valuable assay for forensic genetic testing, especially in crime cases with partially degraded DNA or low amounts of template DNA. However, some difficulties with pull-ups were observed at DNA concentrations of 1000 pg. Rearrangement of the allele windows by changing the lengths of some of the PCR primers would greatly improve the assay, and more robustness towards higher amounts of DNA would allow the use of the DIPplex kit without prior quantification of the samples.  相似文献   
110.
We evaluated the association between radiation therapy and severe capsular contracture or reoperation after 717 delayed breast implant reconstruction procedures (288 1- and 429 2-stage procedures) identified in the prospective database of the Danish Registry for Plastic Surgery of the Breast during the period between 1999 and 2006. A history of radiation therapy was associated with increased risk of severe capsular contracture for 1- and 2-stage procedures, with adjusted hazard ratios (HR) of 3.3 (95% confidence interval [CI]: 0.9-12.4) and 7.2 (95% CI: 2.4-21.4), respectively. Similarly, a history of radiation therapy was associated with a non-significantly increased risk of reoperation after both 1-stage (HR = 1.4; 95% CI: 0.7-2.5) and 2-stage (HR = 1.6; 95% CI: 0.9-3.1) procedures. Reconstruction failure was highest (13.2%) in the 2-stage procedures with a history of radiation therapy. Breast reconstruction approaches other than implants should be seriously considered among women who have received radiation therapy.  相似文献   
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