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81.
The use of cranial and caudal angulated views in the angiographic evaluation of the right coronary artery (RCA) was assessed in 61 patients. Each patient had a standard LAO and RAO view, followed by one or more angled views. The standard LAO view showed the area about the origin of the posterior descending artery (PD0) adequately in 33 of 46 patients (72% ), and the mid and distal portions of the posterior descending artery (PDm&d) adequately in 26/46 (56% ). The standard RAO view showed the PD0 adequately in only 17/46 (37% ) and the PDm&d adequately in 41/46 (89% ). With the LAO cranial view, however, the PD0 was seen well in 45/46 (98% ), and PDm&d was seen well in 44/46 (96% ). The RAO angled views, although of more limited utility, also afforded improved visualization of the distal segments of the RCA. We recommend the use of angled views in the evaluation of the right coronary artery, as these views, particularly the LAO cranial view, afford improved visualization of the distal segments of the RCA.  相似文献   
82.
Venous thromboembolic events (VTEs) represent a serious complication related to hormonal contraception and hormone replacement therapy (HRT). Evidence on hormonal contraceptive- and HRT-related VTEs is derived almost exclusively from observational studies and points to a 2- to 6-fold increased relative risk of VTEs with either therapy. Oral contraceptive pills that contain third-generation progestins (desogestrel or gestodene) seem to be associated with greater VTE risk than those that contain levonorgestrel. Oral contraceptive pill use and HRT are associated with exponentially higher VTE relative risks when used by women who carry an inherited hypercoagulable state. The indication of a lower or a lack of VTE risk associated with the use of progestin-only contraceptives and with transdermal HRT suggests that these therapies may be safer than combination oral contraceptive pills and oral HRT for women in whom oral estrogen therapy is considered contraindicated. Data that support such safety advantages are limited and should be interpreted with caution.  相似文献   
83.
The pilocarpine model in rodents reproduces the main features of mesial temporal lobe epilepsy related to hippocampus sclerosis (MTLE-HS) in humans. It has been demonstrated in this model that the phosphorylation of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor GluR1 subunit is increased 1 h after pilocarpine treatment. Moreover, alterations in the levels of glutamate transporters have been associated with chronic epilepsy in humans. Despite these studies, the profile of these changes has not yet been addressed. We analyzed the protein content and phosphorylation profile of the AMPA receptor GluR1 subunit by western blotting. We also used quantitative real-time polymerase chain reaction to analyze the expression of glial glutamate transporters and the N-methyl-d-aspartate receptor NR1 subunit in the hippocampus (Hip) and cerebral cortex (Ctx) at different time points after pilocarpine-induced status epilepticus (Pilo-SE) in male adult Wistar rats. Biochemical analysis was performed in the Hip and Ctx at 1, 3, 12 h (acute period), 5 days (latent period), and 50 days (chronic period) after Pilo-SE. Key findings include an increase in the phosphorylation of GluR1-Ser845 in the Ctx and GluR1-Ser831 in the Hip at different times during the acute period, and a decrease in the total content of the GluR1 subunit in the Ctx in the latent period. There was a down-regulation of the mRNA expression and protein levels of EAAT1 and EAAT2, and a decrease of the NR1 mRNA expression, in the Ctx during the latent period. Notably, during the chronic period, the EAAT2 mRNA expression and protein levels decreased while the NR1 mRNA levels increased in the Hip. Taken together, our findings suggest a time- and structure-dependent imbalance of glutamatergic transmission in response to Pilo-SE, which might be associated with either epileptogenesis or the seizure threshold in MTLE-HS.  相似文献   
84.
Among the most common features of highly invasive tumors, such as lung adenocarcinomas (AD) and squamous cell carcinomas (SqCC), is the massive degradation of the extracellular matrix. The remarkable qualitative and quantitative modifications of hyaluronidases (HAases), hyaluronan synthases (HAS), E-cadherin adhesion molecules, and the transforming growth factor β (TGF-β) may favor invasion, cellular motility, and proliferation. We examined HAase proteins (Hyal), HAS, E-cadherin, and TGF-β profiles in lung AD subtypes and SqCC obtained from smokers and non-smokers. Fifty-six patients, median age 64 years, who underwent lobectomy for AD (N = 31) and SqCC (N = 25) were included in the study. HAS-1, -2 and -3, and Hyal-1 and -3 were significantly more expressed by tumor cells than normal and stroma cells (P < 0.01). When stratified according to histologic types, HAS-3 and Hyal-1 immunoreactivity was significantly increased in tumor cells of AD (P = 0.01) and stroma of SqCC (P = 0.002), respectively. Tobacco history in patients with AD was significantly associated with increased HAS-3 immunoreactivity in tumor cells (P < 0.01). Stroma cells of SqCC from non-smokers presented a significant association with HAS-3 (P < 0.01). Hyal, HAS, E-cadherin, and TGF-β modulate a different tumor-induced invasive pathway in lung AD subgroups and SqCC. HAases in resected AD and SqCC were strongly related to the prognosis. Therefore, our findings suggest that strategies aimed at preventing high HAS-3 and Hyal-1 synthesis, or local responses to low TGF-β and E-cadherin, may have a greater impact in lung cancer prognosis.  相似文献   
85.
Hepatitis E virus (HEV) causes acute and chronic hepatitis in organ transplant recipients. Serological evidence for HEV infection has been discovered in various population groups in Brazil, and a single acute case has been confirmed. To date, however, no cases of HEV infection in immunocompromised patients have been reported in Brazil. This study aimed to identify and characterize hepatitis E cases in renal transplant recipients in Brazil. A retrospective study was performed on 96 serum samples from renal transplant recipients with unexplained liver enzymes elevation. Three confirmed cases of HEV infection were identified that lacked seroconversion to HEV IgG antibodies. The prevalence of HEV in these patients was 3.1%. Using a sequence analysis of a 304‐nucleotide fragment within ORF2, the strains were classified as genotype 3 with a low percent identity to previously characterized strains. This is the first report of hepatitis E infection in renal transplant recipients in Brazil, and the data indicate that a novel genotype 3 subvariant may be present and that further investigation is necessary to characterize the circulating HEV strains. In this setting, HEV infection should be considered as a potential cause of abnormal liver tests of unknown origin. J. Med. Virol. 85:615–619, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
86.

Propose

After autologous stem cell transplantation (ASCT) the immunological B cell compartment recovers slowly. Delays on the recovery of B cell function after autologous stem cell transplantation are due to the low lymphocytes count and to their intrinsic dysfunction.

Methods

We studied the in vivo B cell reconstitution after ASCT examining the independent effect of polyclonal IgG (PolyIg), Fab or Fc fragments infusions in a murine animal model during a period of 12 weeks. These molecules were used in low doses, mimicking the recommended use of IVIg in the case of hypogammaglobulinemia in humans. Flow cytometry analysis and ELISA tests were conducted to monitor the reconstitution of B cells and serum immunoglobulin production. Panama blot and PCA factor 1 analysis were used to study the kinetics of immunoglobulin repertoires reconstitution. Mechanistic studies were also performed using in vitro cell culture.

Results

During follow-up after ASCT, peripheral B cells expand independently of treatment, correcting the immediate increase in sBAFF (soluble B cell activating factor) induced by previous intense myeloablation. Treatments with Fab and Fc fragments infusions promote significant IgM and IgG production comparing to control. Although the complete recovery of antibody repertoire is only achieved at the end of follow-up after ASCT, there is an earlier and significantly stronger recovery in the treated mice, which is evident at 9 weeks after ASCT. At 30 weeks after ASCT, normal values of antibody repertoire were detected in all individuals. Mechanistic studies show that Fab and Fc fragments promote IgG1 production by indirect pathways.

Conclusions

The results presented here demonstrate that polyclonal immunoglobulin indirectly improves the function of the reconstituted B cells and their IgG production by means of Fc-mediated effects on bystander cells. These results further stimulate the discussion about the advantages of IVIg therapy during immune reconstitution after human ASCT.  相似文献   
87.
Diabetic cardiomyopathy is associated with cardiac muscle remodeling, resulting in myocardial dysfunction, whereas exercise training (ET) is a useful nonpharmacological strategy for the therapy of cardiac diseases. This study tested the effects of low-intensity swimming-training on the structural remodeling of the left ventricle (LV) in growing rats with unmanaged experimental diabetes. Thirty-day-old male Wistar rats were divided into four groups (n = 5/group): sedentary-control (SC), exercised-control (EC), sedentary-diabetic (SD), and exercised-diabetic (ED). Swimming-training rats exercised 5 days/week, 90 min/day, with a load of 5% BW during 8 weeks. Sections of LV were stained with Periodic acid-Schiff, Sirius Red, and Gomori's reticulin. Seven days and 8 weeks after streptozotocin (STZ) induction (60 mg kg−1 BW), blood glucose (BG) in the diabetic groups (SD = 581.40 ± 40.48; ED = 558.00 ± 48.89) was greater (p < 0.05) than in their controls (SC = 88.80 ± 21.70; EC = 85.60 ± 11.55). Swimming-training reduced BG by 23 mg/dL in the diabetics (p > 0.05). The LV of diabetic rats had increased interstitial collagen and reticular fibers on the extracellular matrix and presented glycogen accumulation. More importantly, all these adverse tissue changes induced by STZ were attenuated by ET. Together, these findings support the idea of a beneficial role of exercise in the LV remodeling in rats with unmanaged type-1 diabetes mellitus.  相似文献   
88.
The species of genera Uroderma and Artibeus are medium-sized bats belonging to the family Phyllostomidae and subfamily Stenodermatinae (Mammalia, Chiroptera) from South America. They have a wide distribution in the Neotropical region, with two currently recognized species in Uroderma and approximately 20 species in Artibeus. These two genera have different rates of chromosome evolution, with Artibeus probably having retained the ancestral karyotype for the subfamily. We used whole chromosome paint probe sets from Carollia brevicauda and Phyllostomus hastatus on Uroderma magnirostrum, Uroderma bilobatum, and Artibeus obscurus. With the aim of testing the previous phylogenies of these bats using cytogenetics, we compared these results with published painting maps on Phyllostomidae. The genome-wide comparative maps based on chromosome painting and chromosome banding reveal the chromosome forms that characterize each taxonomic level within the Phyllostomidae and show the chromosome evolution of this family. Based on this, we are able to suggest an ancestral karyotype for Phyllostomidae. Our cladistic analysis is an independent confirmation using multidirectional chromosome painting of the previous Phyllostomidae phylogenies.  相似文献   
89.
European Journal of Clinical Microbiology & Infectious Diseases - In order to improve the diagnosis of giardiasis, fecal samples (high/medium/low concentration of cysts) were processed by the...  相似文献   
90.
Odontology - Endodontics has gained emphasis in the scientific community in recent years due to the increase in clinical and in animal models studies focused on endodontic medicine, which aims to...  相似文献   
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