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41.
A subcutaneous air pouch formed in Sprague-Dawley rats was used to study the effect of diets enriched in γ-linolenic acid (GLA) (in plant seed oil) and eicosapentaenoic acid (EPA) (in fish oil) on acute inflammation induced by monosodium urate crystals. The GLA-enriched diet suppressed significantly the cellular phase of inflammation (polymorphonuclear leukocyte accumulation, crystal phagocytosis, and lysosomal enzyme activity), but it had little effect on the fluid phase (exudate volume and protein concentration). In contrast, the EPA-enriched diet suppressed the fluid phase but not the cellular phase of inflammation. The findings indicate that the fluid and cellular phases of acute inflammation can be controlled independently. A combined diet of fish oil and plant seed oil (EPA-enriched and GLA-enriched) reduced both the cellular and fluid phases of inflammation. Thus, dietary provision of alternative substrates for oxidative metabolism (other than arachidonic acid) modifies monosodium urate crystal-induced acute inflammation.  相似文献   
42.
Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.  相似文献   
43.
Leishmania donovani is an important intracellular protozoal pathogen of humans, which resides solely within mononuclear phagocytes. Phase-contrast microscopy and cinemicroscopy were used to examine the interaction of L. donovani promastigotes with human phagocytes to characterize and quantitate the sequence of events that results in leishmanial infection.  相似文献   
44.
Analysis of 71 ciprofloxacin-resistant (MIC > or = 4 microg/ml) Streptococcus pneumoniae clinical isolates revealed only 1 for which the quinolone resistance-determining regions of the parC, parE, and gyrB genes were genetically related to those of viridans group streptococci. Our findings support the occurrence of interspecies recombination of type II topoisomerase genes; however, its contribution to the emergence of quinolone resistance among pneumococci appears to have been minimal.  相似文献   
45.
This study examined the prevalence and correlates of use of different types of complementary and alternative medicine (CAM) among a sample of children with suspected or recently diagnosed autism. The authors' review of 284 charts of children seen at the Regional Autism Center of The Children's Hospital of Philadelphia, Pennsylvania, found that more than 30% of children were using some CAM, and that 9% were using potentially harmful CAM. Having an additional diagnosis was protective against CAM use and being Latino was associated with CAM use. Having seen a prior provider regarding the child's health condition was predictive of potentially harmful CAM use. Further research is required on cultural differences in treatment decisions about CAM, as well as the reasons for the association between the use of prior providers and CAM. The high prevalence of CAM use among a recently diagnosed sample indicates that clinicians should discuss CAM early in the assessment process.  相似文献   
46.

Background

Access to pediatric antiretroviral formulations is increasing in resource-limited countries, however adult FDCs are still commonly used by antiretroviral therapy (ART) programs.

Objective

To describe long-term effectiveness of using adult FDC of d4T+3TC+NVP (Triomune) in children for HIV treatment.

Methods

Clinical, immunologic, and virologic outcomes of HIV-infected ART-naïve children aged six months to 12 years, were evaluated up to 96 weeks post-ART initiation.

Results

From March 2004 to June 2006, 104 children were followed with a median age of 5.4 years, median CD4 cell percent and HIV-1 RNA were 11.0% (IQR 6.7–13.9) and 348,846copies/mL (IQR 160,941–681,313) respectively at baseline. Using Kaplan-Meir estimates, 75% of children had undetectable viral loads (<400copies/mL) at 96weeks of ART. Children with a baseline CD4 cell percent >15% were 3 times more likely to achieve viral load <400copies/mL than those with baseline CD4 cell percent <5% after adjusting for baseline age {aHR = 3.03 (1.10–8.32), p=0.03}; no difference was found among those with CD4 cell percent >5–14.9% and <5%.

Conclusion

Treatment with generic adult FDC for HIV-infected Ugandan children led to sustained clinical, immunologic and virologic response during 96 weeks of ART. Early initiation of ART is key to achieving virological success.  相似文献   
47.
The simian immunodeficiency virus (SIV) nef gene is an important determinant of viral load and acquired immunodeficiency syndrome (AIDS) in macaques. A role(s) for the HIV-1 nef gene in infection and pathogenesis was investigated by constructing recombinant viruses in which the nef gene of the pathogenic molecular clone SIVmac239 nef was replaced with either HIV-1sf2nef or HIV-1sf33nef. These chimeras, designated SHIV-2nef and SHIV-33nef, expressed HIV-1 Nef protein and replicated efficiently in cultures of rhesus macaque lymphoid cells. In two SHIV-2nef-infected juvenile rhesus macaques and in one of two SHIV-33nef-infected juvenile macaques, virus loads remained at low levels in both peripheral blood and lymph nodes in acute and chronic phases of infection (for >83 weeks). In striking contrast, the second SHIV-33nef-infected macaque showed high virus loads during the chronic stage of infection (after 24 weeks). CD4+ T-cell numbers declined dramatically in this latter animal, which developed simian AIDS (SAIDS) at 47-53 weeks after inoculation; virus was recovered at necropsy at 53 weeks and designated SHIV-33Anef. Sequence analysis of the HIV-1sf33 nef gene in SHIV-33Anef revealed four consistent amino acid changes acquired during passage in vivo. Interestingly, one of these consensus mutations generated a tyr-x-x-leu (Y-X-X-L) motif in the HIV-1sf33 Nef protein. This motif is characteristic of certain endocytic targeting sequences and also resembles a src-homology region-2 (SH-2) motif found in many cellular signaling proteins. Four additional macaques infected with SHIV-33Anef contained high virus loads, and three of these animals progressed to fatal SAIDS. Several of the consensus amino acid changes in Nef, including Y-X-X-L motif, were retained in these recipient animals exhibiting high virus load and disease. In summary, these findings indicate that the SHIV-33Anef chimera is pathogenic in rhesus macaques and that this approach, i.e., construction of chimeric viruses, will be important for analyzing the function(s) of HIV-1 nef genes in immunodeficiency in vivo, testing antiviral therapies aimed at inhibiting AIDS, and investigating adaptation of this HIV-1 accessory gene to the macaque host.  相似文献   
48.
SIV/HIV-1 (SHIV) chimeric clones, constructed by substituting portions of the pathogenic molecular clone SIVmac239 with counterpart portions from HIV-1 clones, provide a means to analyze functions of selected HIV-1 genes in vivo in nonhuman primates. Our studies focused on SHIVSF33, which contains the vpu, tat, rev, and env genes of the cytopathic, T-cell line tropic clone HIV-1sf33 (subtype-B); this clone has a premature stop codon in the vpu gene. In three juvenile macaques inoculated intravenously with SHIVSF33, low-level persistent infection was established; no disease was observed for a period of >2 years. However, at approximately 16 months p.i., one of four SHIVSF33-infected juvenile macaques exhibited an increase in virus load, depletion of CD4(+) T cells in peripheral blood and lymph nodes, and other symptoms of simian AIDS (SAIDS). Virus recovered from this animal in the symptomatic stage was designated SHIVSF33a (A, adapted); this virus displayed multiple amino acid sequence changes throughout the HIV-1 env gene compared with the input SHIVSF33 clone. Additionally, a mutation in all clones from SHIVSF33a restored the open reading frame for the vpu gene. In vitro evaluations in tissue-culture systems revealed that SHIVSF33a replicated to higher levels and exhibited greater cytopathicity than SHIVSF33. Furthermore cloned env genes for SHIVSF33a were more fusogenic in a cell-fusion assay compared with the env gene of the SHIVSF33. Intravenous inoculation of SHIVsf33a into juvenile and newborn macaques resulted in a rapid decline in CD4(+) T cells to very low levels and development of a fatal AIDS-like disease. A cell-free preparation of this pathogenic chimeric virus also established persistent infection when applied to oral mucosal membranes of juvenile macaques and produced a fatal AIDS-like disease. These studies on pathogenic SHIVSF33a establish the basis for further investigations on the role of the HIV-1 env gene in virus adaptation and in mechanism(s) of immunodeficiency in primates; moreover, the chimeric virus SHIVSF33a can play a role in elucidating mucosal membrane transmission and development of antiviral vaccines in newborns as well as juvenile and adult macaques.  相似文献   
49.
The purpose of this study was to determine the relationships among preconception stressful life events (PSLEs), women’s alcohol and tobacco use before and during pregnancy, and infant birthweight. Data were from the Early Childhood Longitudinal Study-Birth Cohort (n?=?9,350). Data were collected in 2001. Exposure to PSLEs was defined by indications of death of a parent, spouse, or previous live born child; divorce or marital separation; or fertility problems prior to conception. Survey data determined alcohol and tobacco usage during the 3 months prior to and in the final 3 months of pregnancy. We used staged multivariable logistic regression to estimate the effects of women’s substance use and PSLEs on the risk of having a very low (<1,500 g, VLBW) or low (1,500–2,499 g, LBW) birthweight infant, adjusting for confounders. Women who experienced any PSLE were more likely to give birth to VLBW infants (adjusted odds ratio [AOR]?=?1.35; 95 % confidence interval [CI]?=?1.10–1.66) than women who did not experience any PSLE. Compared to women who never smoked, women who smoked prior to conception (AOR?=?1.31; 95 % CI?=?1.04–1.66) or during their last trimester (AOR?=?1.98; 95 % CI?=?1.56–2.52) were more likely to give birth to LBW infants. PSLEs and women’s tobacco use before and during pregnancy are independent risk factors for having a lower birthweight baby. Interventions to improve birth outcomes may need to address women’s health and health behaviors in the preconception period.  相似文献   
50.
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