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41.
Allocation of deceased donor kidneys is based on several criteria; however, the final decision to accept or reject the offered kidney is made by the potential recipient's transplant team (surgeon/nephrologist). Several considerations including assessment of the donor quality, the HLA match between the donor and the recipient, several recipient factors, the geographical location of the recipient, and the organ all affect the decision of whether or not to finally accept the organ for a particular recipient. This decision needs to be made quickly, often on the spot. Maximizing the benefit from this scarce resource raises difficult ethical issues. The philosophies of equity and utility are often competing. This article will discuss the several considerations for the pediatric nephrologist while accepting a deceased donor kidney for a particular pediatric patient.  相似文献   
42.
Generally, when we talk or think about science, we refer to that of Western or industrialized societies, assuming that science is only there in those societies and quite often implying that scientific rigour or interest is absent in other societies. The role of science is to help mankind meet the various demands for exploiting natural resources in the best possible way without adversely affecting the environment. In most societies, there exists a rich body of knowledge based on how to meet the demands of that particular society but quite often these are ignored. We need to look at indigenous science and technology particularly when an existing body of knowledge is available. Perhaps it is better to develop it instead of disregarding it in the name of scientific progress. The prevailing health and medical system, the Western system, has unfortunately failed to meet the needs of all. In most countries, frightening policy changes place less and less emphasis on the social and welfare sectors and higher emphasis on the economic and infrastructure sectors. As such, funds allocated to health are going down. The implications of such a trend in countries where health insurance is unaffordable for the majority, is unimaginable. In this changing situation, the conditions of the poor, particularly the indigenous people, have become critical. In this paper, challenges and opportunities for indigenous health practices are examined in the context of forest situations, forest policy and related environmental issues.  相似文献   
43.
44.
Clinical Rheumatology - A project aimed to develop and deliver a clinical training course in Accra, Ghana, to increase patient access to physicians trained in the diagnosis, treatment and...  相似文献   
45.
Frequent occurrence of hypogonadotropic hypogonadism in type 2 diabetes   总被引:6,自引:0,他引:6  
Type 2 diabetes is associated with lower total testosterone (T) levels in cross-sectional studies. However, it is not known whether the defect is primary or secondary. We investigated the prevalence of hypogonadism in type 2 diabetes by measuring serum total T, free T (FT), SHBG, LH, FSH, and prolactin (PRL) in 103 type 2 diabetes patients. FT was measured by equilibrium dialysis. FT was also calculated by using T and SHBG (cFT). Hypogonadism was defined as low FT or cFT. The mean age was 54.7 +/- 1.1 yr, mean body mass index (BMI) was 33.4 +/- 0.8 kg/m(2), and mean HbA1c was 8.4 +/- 0.2%. The mean T was 12.19 +/- 0.50 nmol/liter (351.7 +/- 14.4 ng/dl), SHBG was 27.89 +/- 1.65 nmol/liter, and FT was 0.250 +/- 0.014 nmol/liter. Thirty-three percent of patients were hypogonadal. LH and FSH levels were significantly lower in the hypogonadal group compared with patients with normal FT levels (3.15 +/- 0.26 vs. 3.91 +/- 0.24 mIU/ml for LH and 4.25 +/- 0.45 vs. 5.53 +/- 0.40 mIU/ml for FSH; P < 0.05). There was a significant inverse correlation of BMI with FT (r = -0.382; P < 0.01) and T (r = -0.327; P < 0.01). SHBG correlated inversely with BMI (r = -0.267; P < 0.05) but positively with age (r = 0.538; P < 0.001) and T (r = 0.574; P < 0.001). FT correlated strongly with cFT (r = 0.919; P < 0.001) but not with SHBG. LH levels correlated positively with FT (r = 0.287; P < 0.05). We conclude that hypogonadotropic hypogonadism occurs commonly in type 2 diabetes.  相似文献   
46.
47.
The prolonged voluntary closure of the glottis during the supraglottic and super-supraglottic swallowing techniques may create the Valsalva maneuver. The Valsalva maneuver has been associated with sudden cardiac death and cardiac arrhythmias. This study describes the effects of the supraglottic and super-supraglottic swallowing techniques on the cardiovascular system. Subjects included 23 patients from an acute inpatient rehabilitation hospital. Subject groups included recent stroke, dysphagia, and a history of coronary artery disease (Group 1, N = 11), recent stroke and dysphagia with no known coronary artery disease (Group 2, N = 4), and orthopedic diagnosis with no known dysphagia or coronary artery disease (Group 3, N = 8). Cardiac status was moni-tored for 4 hours during swallowing training, regular therapy sessions, and a meal. For Groups 1 and 2, 86.6% (13 out of 15) of the subjects demonstrated abnormal cardiac findings during the swallowing session including supraventricular tachycardia, premature atrial contractions, and premature ventricular contractions. Arrhythmia subsided within a few minutes after the session and did not occur during other activities. In Group 3 (control group), none of the subjects demonstrated abnormal cardiac findings except for bradycardia in one subject. It is suggested that the supraglottic and super-supraglottic swallow maneuvers may be contraindicated for patients with a history of stroke or coronary artery disease.  相似文献   
48.
The concentration of testosterone in saliva is probably in equilibrium with the concentration of cellular exchangeable testosterone in salivary gland, and these pools are a function of hormone transplant from the plasma compartment, and hormone metabolism in salivary gland cells. Both of these processes were examined in the present study using the carotid injection technique in normal and pilocarpine-stimulated ketamine-anesthetized rats. Both testosterone and estradiol were rapidly transported across salivary gland capillaries in vivo from the circulating albumin-bound pool. Estradiol, but not testosterone, was also rapidly transported into salivary gland from the circulating human sex hormone-binding globulin-bound pool. Hormone transport was several-fold greater than the capillary transport of [3H]bovine albumin, indicating that bound hormone was available for transport across salivary gland capillaries via an enhanced dissociation mechanism, with the plasma protein primarily residing in the plasma compartment. This result was confirmed by thaw-mount autoradiography, which showed diffuse distribution of [3H]testosterone in salivary gland, but vascular retention of [3H]bovine albumin. The concentration of exchangeable cellular testosterone in rat saliva was less than 4% of the total or plasma exchangeable testosterone in the rat. This marked discrepancy between the concentration of plasma and cellular exchangeable hormone suggested that there was rapid metabolism of androgen by salivary gland in vivo. This was confirmed by chromatographic separation of [3H] testosterone and labeled metabolites in homogenates of salivary gland. By 60 sec after injection, approximately 30% of the radioactivity in the salivary gland was in the form of androgen metabolites, which primarily comigrated with an androstenedione standard. The data indicate that albumin-bound testosterone, albumin-bound estradiol, and sex hormone-binding globulin-bound estradiol are all exchangeable in salivary gland capillaries. The low concentration of cellular exchangeable testosterone in salivary gland appears to be due to rapid tissue metabolism of this hormone. Thus, changes in androgen metabolism may alter salivary gland hormone concentrations independent of any change in the concentration of biologically active hormone in plasma.  相似文献   
49.
The Non‐Motor Symptoms Scale (NMSS) was developed and validated in 2007 as the first instrument for the comprehensive assessment of a range of non‐motor symptoms in Parkinson's disease (PD). Thirteen years have elapsed since its introduction and extensive international validation with good psychometric attributes has been carried out. Here, we review the validation data of the NMSS and its cross‐validity with other scales, and describe the key evidence derived from use of the NMSS in clinical studies. To date, over 100 clinical studies and trials have made use of it as an outcome measure, showing consistent and strong correlations between NMSS burden and health‐related quality of life measures. Moreover, the scale has shown to be capable of detecting longitudinal changes in non‐motor symptoms, where studies have shown differential changes over time of several of the NMSS domains. The scale has become a key outcome in several randomized clinical trials. Highlighting the prevalence and importance of non‐motor symptoms to quality of life in patients with PD, the development of NMSS has also been useful in signposting clinical and biomarker based research addressing non‐motor symptoms in PD.  相似文献   
50.
Avian pathogenic Escherichia coli (APEC) causes respiratory and systemic disease in poultry. Sequencing of a multilocus sequence type 95 (ST95) serogroup O1 strain previously indicated that APEC resembles E. coli causing extraintestinal human diseases. We sequenced the genomes of two strains of another dominant APEC lineage (ST23 serogroup O78 strains χ7122 and IMT2125) and compared them to each other and to the reannotated APEC O1 sequence. For comparison, we also sequenced a human enterotoxigenic E. coli (ETEC) strain of the same ST23 serogroup O78 lineage. Phylogenetic analysis indicated that the APEC O78 strains were more closely related to human ST23 ETEC than to APEC O1, indicating that separation of pathotypes on the basis of their extraintestinal or diarrheagenic nature is not supported by their phylogeny. The accessory genome of APEC ST23 strains exhibited limited conservation of APEC O1 genomic islands and a distinct repertoire of virulence-associated loci. In light of this diversity, we surveyed the phenotype of 2,185 signature-tagged transposon mutants of χ7122 following intra-air sac inoculation of turkeys. This procedure identified novel APEC ST23 genes that play strain- and tissue-specific roles during infection. For example, genes mediating group 4 capsule synthesis were required for the virulence of χ7122 and were conserved in IMT2125 but absent from APEC O1. Our data reveal the genetic diversity of E. coli strains adapted to cause the same avian disease and indicate that the core genome of the ST23 lineage serves as a chassis for the evolution of E. coli strains adapted to cause avian or human disease via acquisition of distinct virulence genes.  相似文献   
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