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991.
Cutaneous polyarteritis nodosa (CPAN) is an uncommon form of vasculitis involving small and medium sized arteries of unknown etiology. The disease can be differentiated from polyarteritis nodosa by its limitation to the skin and lack of progression to visceral involvement. The characteristic manifestations are subcutaneous nodule, livedo reticularis, and ulceration, mostly localized on the lower extremity. Arthralgia, myalgia, peripheral neuropathy, and constitutional symptoms such as fever and malaise may also be present. We describe a 34-yr-old woman presented with severe ischemic change of the fingertip and subcutaneous nodules without systemic manifestations as an unusual initial manifestation of CPAN. Therapy with corticosteroid and alprostadil induce a moderate improvement of skin lesions. However, necrosis of the finger got worse and the finger was amputated.  相似文献   
992.
Summary Although winter dysentery (WD), which is caused by the bovine coronavirus (BCoV) is characterized by the sudden onset of diarrhea in many adult cattle in a herd, the pathogenesis of the WD-BCoV is not completely understood. In this study, colostrum-deprived calves were experimentally infected with a Korean WD-BCoV strain and examined for viremia, enteric and nasal virus shedding as well as for viral antigen expression and virus-associated lesions in the small and large intestines and the upper and lower respiratory tract from 1 to 8 days after an oral infection. The WD-BCoV-inoculated calves showed gradual villous atrophy in the small intestine and a gradual increase in the crypt depth of the large intestine. The WD-BCoV-infected animals showed epithelial damage in nasal turbinates, trachea and lungs, and interstitial pneumonia. The WD-BCoV antigen was detected in the epithelium of the small and large intestines, nasal turbinates, trachea and lungs. WD-BCoV RNA was detected in the serum from post-inoculation day 3. These results show that the WD-BCoV has dual tropism and induces pathological changes in both the digestive and respiratory tracts of calves. To our knowledge, this is the first detailed report of dual enteric and respiratory tropisms of WD-BCoV in calves. Comprehensive studies of the dual tissue pathogenesis of the BCoV might contribute to an increased understanding of similar pneumoenteric CoV infections in humans.  相似文献   
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Kim J  Kim IS  Cho TH  Lee KB  Hwang SJ  Tae G  Noh I  Lee SH  Park Y  Sun K 《Biomaterials》2007,28(10):1830-1837
Acrylated hyaluronic acid (HA) was used as a scaffold for bone morphogenic protein-2 (BMP-2) and human mesenchymal stem cells (hMSCs) for rat calvarial defect regeneration. HA was acrylated by two-step reactions: (1) introduction of an amine group using adipic acid dihydrazide (ADH); (2) acrylation by N-acryloxysuccinimide. Tetrathiolated poly(ethylene) glycol (PEG-SH(4)) was used as a cross-linker by a Michael-type addition reaction and the hydrogel was formed within 10min under physiological conditions. This hydrogel is degraded completely by 100U/ml hyaluronidase in vitro. hMSCs and/or BMP-2 was added during gelation. Cellular viability in vitro was increased up to 55% in the hydrogels with BMP-2 compared with the control. For in vivo calvarial defect regeneration, five different samples (i.e., control, hydrogel, hydrogel with BMP-2, hydrogel with MSCs, and hydrogel with BMP-2 and MSCs) were implanted for 4 weeks. The histological results demonstrated that the hydrogels with BMP-2 and MSCs had the highest expression of osteocalcin and mature bone formation with vascular markers, such as CD31 and vascular endothelial growth factors, compared with the other samples. This study demonstrated that HA base hydrogel can be used for cell and growth factor carriers for tissue regeneration.  相似文献   
996.
PURPOSE: Diabetic nephropathy is the most serious of complications in diabetes mellitus. Thiazolidinedione (TZD) is thought to ameliorate diabetic nephropathy; however, the mechanism underlying this effect has not been elucidated. We hypothesized that the vascular endothelial growth factor (VEGF) participates in the pathogenesis of diabetic nephropathy and that TZD may be beneficial for the treatment of diabetic nephropathy because of the effect it has on VEGF. MATERIALS AND METHODS: 23 Otsuka- Long-Evans-Tokushima-Fatty (OLETF) rats and eight control Long-Evans-Tokushima-Otsuka (LETO) rats were divided into the following four groups: LETO group, control OLETF group, pioglitazone treated group (10mg/ kg/day), and rosiglitazone treated group (3mg/kg/day). RESULTS: A progressive increase in urinary protein excretion was observed in the diabetic rats. Glomerular VEGF expression in the control OLETF rats was significantly higher than in the control LETO rats. However, there was a significant reduction in both the glomerular VEGF expression and the VEGF mRNA levels after treatment with pioglitazone and rosiglitazone. The twenty-four hour urine protein levels were significantly decreased in both groups of the treated OLETF rats. CONCLUSION: These results suggest that TZD may have beneficial effects on diabetic nephropathy by reducing the VEGF expression.  相似文献   
997.
Acinetobacter baumannii has emerged as a serious cause of nosocomial infections. Rapid identification of this pathogen is required so that appropriate therapy can be given and outbreaks controlled. This study evaluated a multiplex PCR and an automated ribotyping system for the rapid identification of Acinetobacter baumannii. In total, 22 different reference strains and 138 clinical isolates of Acinetobacter spp., identified by 16S-23S rRNA intergenic spacer (ITS) sequence analysis, were evaluated. All A. baumannii isolates (82 clinical isolates and one reference strain) were identified by the multiplex PCR method (specificity 100%). The sensitivity and specificity of the ribotyping system for identification of A. baumannii were 85.5% (71/83) and 93.5% (72/77), respectively. An additional 100 clinical isolates belonging to the Acinetobacter calcoaceticus-A. baumannii complex were used to compare these two methods for identification of A. baumannii, and this comparison revealed a level of disagreement of 14% (14 isolates). The accuracy of the multiplex PCR was 100%, which was confirmed by sequence analysis of the ITS and recA gene of these isolates. Thus, the multiplex PCR method dramatically increased the efficiency and speed of A. baumannii identification.  相似文献   
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999.
BACKGROUND: The exact mechanism of a chronic nonproductive cough is sometimes unclear when patients who are without symptoms or signs indicating the major causes of chronic cough remain undiagnosed. OBJECTIVE: We hypothesized that some neurochemical alterations in the sensory nerves in the cough reflex may occur in the upper airway of chronic nonproductive cough patients. METHODS: We took nasal lavage fluid (NLF) specimens from 38 patients with a chronic nonproductive cough as the sole presenting symptom. All 38 had normal chest radiography, spirometry, and bronchial responsiveness. We likewise took NLF specimens from 14 healthy control subjects. We used a capsaicin cough provocation test to determine cough sensitivity and considered the value of C5 (the lowest capsaicin concentration inducing 5 consecutive coughs) as an index of cough sensitivity. We measured levels of substance P of NLF specimens by using ELISA. In addition, we evaluated the clinical response of each patient after subsequent therapeutic trials with an antihistamine and decongestant for 2 weeks. RESULTS: By using capsaicin cough sensitivity as the basis for grouping the study subjects, we divided the patients into 2 groups: an increased cough sensitivity group (ICS, C5 <32 mumol/L) and a normal cough sensitivity (NCS) group. Patients with ICS showed an elevated SP concentration in NLF (median value, 408 pg/mL) compared with that of the NCS group (237 pg/mL) and the control subjects (138 pg/mL) (P <.01). The median value of the percentage of remnant cough after therapeutic trial compared with the cough status before treatment was significantly higher in the ICS subgroup (70%) than that of NCS (25%) (P <.05). CONCLUSIONS: Elevated substance P contents in NLF specimens were associated with ICS in patients with chronic nonproductive cough, suggesting a neurochemical abnormality in the upper airway.  相似文献   
1000.
Mutational analysis of Noxa gene in human cancers   总被引:4,自引:0,他引:4  
There has been mounting evidence that dysregulation of apoptosis is involved in the mechanisms of cancer development and somatic mutations of apoptosis-related genes have been reported in human cancers. Noxa, a Bcl-2 homology 3 (BH3)-only member of the Bcl-2 family, is known to interact with anti-apoptotic Bcl-2 family members and induces apoptosis. The aim of this study was to explore the possibility that the Noxa gene is mutated in human cancers. We have analyzed the entire coding region and all splice sites of the Noxa gene for the detection of somatic mutations in a series of human cancers, including carcinomas from stomach, colon, liver, urinary bladder and lung by polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP), and DNA sequencing. We found one somatic mutation of the Noxa gene in a transitional cell carcinoma (TCC) of the urinary bladder. To evaluate the functional alterations of the mutant in apoptosis, we overexpressed the mutant and wild-type Noxa in 293T and HeLa cells, but could not find any significant difference in cell death between the wild-type and mutant Noxa. These data suggest that Noxa is rarely mutated in human carcinomas and that the contribution of Noxa gene mutation in the pathogenesis of human cancer might not be related to cell death mechanisms.  相似文献   
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