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171.
A 69-year-old Japanese female was admitted to our hospital due to a 2-month history of vomiting after eating. Examination of the small intestinal tract revealed a tumor with calcification in the inner portion, from the horizontal portion to the ascending portion of the duodenum, and jejunojejunostomy was performed. The pathological findings of the tumor gave a diagnosis of non-Hodgkin's lymphoma, diffuse small cleaved cell (Working Formulation classification), B cell type, of the jejunum. Calcification is rarely found in untreated malignant lymphoma and 15 cases of untreated malignant lymphoma with calcification have been reviewed.  相似文献   
172.
The proliferation of hepatic stellate cells (HSCs) is a critical step in hepatic fibrogenesis. Platelet-derived growth factor (PDGF) is the most potent mitogen for HSCs. We investigated the role of nonphagocytic NAD(P)H oxidase-derived reactive oxygen species (ROS) in PDGF-induced HSC proliferation. The human HSC line, LI-90 cells, murine primary-cultured HSCs, and PDGF-BB were used in this study. We examined the mechanism of PDGF-BB-induced HSC proliferation in relation to the role of a ROS scavenger and diphenylene iodonium, an inhibitor of NAD(P)H oxidase. We also measured ROS production with the aid of chemiluminescence. We showed that PDGF-BB induced proliferation of HSCs through the intracellular production of ROS. We also demonstrated that HSCs expressed key components of nonphagocytic NAD(P)H oxidase (p22phox, gp91phox, p47phox, and p67phox) at both the messenger RNA and protein levels. Diphenylene iodonium suppressed PDGF-BB-induced ROS production and HSC proliferation. Coincubation of H2O2 and PDGF-BB restored the proliferation of HSCs that was inhibited by diphenylene iodonium pretreatment. Phosphorylation of the mitogen-activated protein kinase (MAPK) family constitutes a signal transduction pathway of cell proliferation. Our data demonstrate that NAD(P)H oxidase-derived ROS induce HSC proliferation mainly through the phosphorylation of p38 MAPK. Moreover, an in vivo hepatic fibrosis model also supported the critical role of NAD(P)H oxidase in the activation and proliferation of HSCs. In conclusion, NAD(P)H oxidase is expressed in HSCs and produces ROS via activation of NAD(P)H oxidase in response to PDGF-BB. ROS further induce HSC proliferation through the phosphorylation of p38 MAPK.  相似文献   
173.
Concentrations of immunoreactive thyrotropin-releasing hormone (ir-TRH) were measured by specific radioimmunoassay in the spinal cord of six patients with amyotrophic lateral sclerosis (ALS) and seven with non-neurological diseases. Ir-TRH concentrations were the highest in the anterior horn, compared with other areas of the spinal cord, both in non-neurological diseases and ALS. Ir-TRH concentrations in the anterior horn of ALS were significantly lower than in non-neurological diseases, but were the same in both groups in other parts of the spinal cord (e.g. posterior horn, frontal part, lateral and central part, posterior part). Ir-TRH concentrations in rat spinal cords were stable for up to seven hours when spinal cord was stored after death at 4 degrees C or 22 degrees C. An elution profile of methanol-extracted human spinal cord on Sephandex G-10 column was identical to that of synthetic TRH. The cell population in the anterior horn in ALS was decreased markedly. The findings suggest that TRH is present in the human spinal cord and its decreased concentrations in the anterior horn of ALS may be due to a decrease in the cell population.  相似文献   
174.
Eight distinct and potentially causative mutations were identified in eight unrelated Japanese patients with protein S (PS) deficiency, by direct DNA sequencing of the protein Salpha (PSalpha) gene-specific polymerase chain reaction products of all 15 exons and exon/intron boundaries. There were five missense mutations, including two novel mutations (Cys80Tyr and Arg314His), and three showed a major impact on the expected gene products: novel mutations of a 5-bp deletion (delCTCTG887:Cys206Stop) and a nonsense mutation (Glu208Stop), as well as a previously reported splice site (exon 10 +5 A-->G) mutation. One of the patients showed compound heterozygosity for delCTCTG887 and 732A-->G. Investigation for the cosegregation state of these two mutations with PS deficiency in the patient's family suggested that the delCTCTG887 mutation was responsible for the abnormal phenotype and that the 732A-->G (Lys155Glu) mutation did not appear to play a key role. However, we also identified the same 732A-->G (Lys155Glu) mutation in an unrelated patient with apparent PS deficiency with severe pulmonary embolism, and found that this mutation seemed to cosegregate with a PS-deficient state in her family members. These data implied that unknown factor(s) other than the 732A-->G mutation itself might influence phenotypic expression of PS status in different individuals.  相似文献   
175.
We describe a rare case of pancreas divisum associated with a giant retention cyst (cystic dilatation of the dorsal pancreatic duct), presumably formed following obstruction of the minor papilla. The patient was treated by pancreatico(cysto)jejunostomy. A 50-year-old man was admitted with complaints of increasing upper abdominal distension and body weight loss. There was no previous history of pancreatitis, gallstones, drinking, or abdominal injury. An elastic-hard tumor-like resistance was palpable in the upper abdomen. Computed tomography and ultrasound (US) examinations revealed a giant cystic lesion expanding from the pancreas head to the tail. Endoscopic retrograde cholangiopancreatography findings showed a looping pancreatic duct which drained only the head and uncinate process of the pancreas to the main papilla. A US-guided puncture to the cystic lesion revealed that the lesion continued to the main pancreatic duct in the tail of pancreas. The lesion was connected to a small cystic lesion, which was located inside the minor papilla, and ended there. The amylase level in liquid aspirated from the cyst was 37 869 IU/l, and the result of cytological examination of the liquid showed class II. A pancreatico(cysto)jejunostomy was performed, with the diagnosis being pancreas divisum associated with a retention cyst following obstruction of the minor papilla. The histological findings of a specimen from the cyst wall revealed that the wall was a pancreatic duct covered with mildly inflammatory duct epithelium; there was no evidence of neoplasm. The patient is currently well, and a CT examination 2 years after the operation showed disappearance of the cyst and normal appearance of the whole pancreas. Received: April 24, 2001 / Accepted: September 14, 2001  相似文献   
176.
Background: To evaluate whether hydrofluoroalkane-beclomethasone dipropionate (HFA-BDP) controls eosinophilic inflammation, including that in the distal airways, more effectively than fluticasone propionate (FP) Diskus(R). Methods: Fifty patients with well-controlled mild to moderate persistent asthma using FP for more than 6 months were randomly assigned to FP and HFA-BDP groups, and the treatment regimens of the two groups were switched twice between FP and HFA-BDP in a double cross-over manner at 3-month intervals after 2-week washout periods. Evidence of eosinophilic inflammation in blood and induced sputum samples was assessed, together with pulmonary function testing and an Asthma-related Quality of Life Questionnaire (AQLQ) survey after each treatment period. Results: The peripheral blood differential eosinophil count and sputum levels of eosinophil cationic protein (ECP) showed reciprocal changes during the study periods in both groups. The blood differential eosinophil count was significantly lower during the HFA-BDP than during the FP treatment period in both the FP (p = 0.004) and the HFA-BDP (p = 0.020) group. The late-phase induced sputum ECP level was significantly decreased during the HFA-BDP treatment period in both the FP (p = 0.016) and the HFA-BDP group (p = 0.023). The significant elevation of surfactant protein D values in the late-phase sputum observed in both groups indicated that late-phase sputum was obtained mainly from proximal peripheral airways. Both symptom and activity limitation domains of the AQLQ in the HFA-BDP group significantly increased after switching from FP to HFA-BDP. There were no significant changes in pulmonary function indices in either group at any time during the study. Conclusions: HFA-BDP improved residual eosinophilic inflammation in asthmatic airways, including distal airways, more effectively than FP.  相似文献   
177.
A 34-year-old man was admitted with dyspnea and low grade fever. Chest radiograph and computed tomography (CT) showed bilateral, ground glass opacities and perihilar consolidation. Bronchoalveolar lavage (BAL) was performed. The percentage of eosinophils in the BAL fluid (BALF) was elevated (20.5%). BALF smear and culture showed normal flora. Acute eosinophilic pneumonia was diagnosed and steroid therapy was performed. Afterwards he was transferred to our hospital. The HIV antibody was positive and peripheral blood CD-4 positive lymphocytes decreased to 10/microl, cytomegalovirus (CMV) antigenemia was positive and beta-D-glucan increased. CMV infection and pneumocystis pneumonia (PCP) complicated with AIDS was diagnosed. Trimethoprim/sulfamethoxazole, ganciclovir, and antifungal drugs were administered, but he suffered pneumothorax on the 18th day after admission and died. Histopathologic findings from an autopsy lung specimen revealed CMV infection and PCP. It is known that the percentage of eosinophils in the BALF increases in some cases of PCP complicated with AIDS. We emphasize that it is necessary to consider PCP when the percentage of eosinophils in the BALF increase.  相似文献   
178.
Abstract: Background/Aims: The aim of this study was to clarify the candidate cells for and the mechanism of superoxide anion (O2·?) release into the hepatic sinusoids during short‐term exposure to ethanol. Methods: The rat liver was perfused continuously with ethanol (a substrate for alcohol dehydrogenase) or tert‐buthanol (not a substrate for alcohol dehydrogenase) for 20 min at a final concentration of 40 mM. In order to detect O2·? production, MCLA (2‐methyl‐6‐[p‐methoxyphenyl]‐3,7‐dihydroimidazo[1,2‐a]pyrazin‐3‐one), a Cypridina luciferin analogue, was simultaneously infused and MCLA‐enhanced chemiluminescence was measured. The effects of gadolinium chloride (GdCL3) (a suppressor of Kupffer cells (KCs)), staurosporine (ST) (an inhibitor of serine–threonine kinases, including protein kinase C), diphenyleneiodonium chloride (DPI) (an inhibitor of NADPH oxidase), ibuprofen (IB) (an inhibitor of cyclooxygenase) and 4‐methylpyrazole (4MP) (an inhibitor of ethanol metabolism) on the ethanol‐induced chemiluminescence were also evaluated. Sites where O2·? could be released were determined by histochemical detection of nitro blue tetrazolium reduction. Results: Both ethanol and tert‐buthanol rapidly caused O2·? release. GdCL3 suppressed the ethanol‐induced O2·? release by 61%. Staurosporine and DPI, but neither IB nor 4‐MP, also significantly inhibited the ethanol‐induced O2·? release. In the histochemical examination, ethanol‐stimulated liver showed blue formazan precipitate on both sinusoidal endothelial cells (SECs) and Kupffer cells (KCs), whereas the GdCl3‐pretreated liver had the precipitate only on SECs. Conclusions: This study shows that ethanol itself stimulates both SECs and KCs to release O2·? via activation of NADPH oxidase probably involving protein kinase C (PKC).  相似文献   
179.
BACKGROUND: GIK-201Tl imaging reportedly improves the detection of viable myocardium, so the present study evaluated whether it can detect myocardial viability after acute myocardial infarction (AMI). METHODS AND RESULTS: Resting 201Tl and 99mTc-pyrophosphate (PYP) dual single photon emission computed tomography (SPECT) and 201Tl SPECT after 201Tl with GIK (10% glucose, insulin 5 U, and KCl 10 mmol) infusion (GIK-201Tl) were performed in 25 AMI patients within 10 days of admission. GIK-201Tl SPECT images were obtained immediately and 4 h after infusion. Left ventriculography (LVG) was performed within 3 weeks and at 6 months when follow-up 201Tl SPECT was also performed. From 20 SPECT segments, both the summed defect score (RDS) and the number of defect segments (ES) were calculated. The infarcted area was defined as 99mTc-PYP uptake segments. Wall motion was estimated in 7 LVG segments. The ES of R-201Tl (5.5 +/- 2.8), immediate GIK-201Tl (4.0 +/- 2.3), and 4-h GIK-201Tl (5.6 +/- 2.7) were lower than that of 99mTc-PYP (7.5 +/- 4.1) (p<0.05), and the ES had significantly declined 6 months later on 201Tl (3.5 +/- 2.8) (p<0.05). Although the RDS of R-201Tl (11.3 +/- 7.9) and 4-h GIK-201Tl (11.2 +/- 6.3) were greater than at the 6-month 201Tl (7.1 +/- 6.5), immediate GIK-201Tl (7.4 +/- 6.5) was equivalent to follow-up 201Tl. The sensitivity of immediate GIK-201Tl was highest among the imaging methods. CONCLUSION: To detect myocardial viability after AMI, early imaging with GIK-201Tl is more useful than resting 201Tl imaging.  相似文献   
180.
We describe a 59-year-old woman with sick sinus syndrome (SSS) and arrhythmogenic right ventricular cardiomyopathy (ARVC). Diagnosis of SSS was made because she had frequent episodes of sinus arrest with prolonged ventricular asystole. Cardiac images showed a dilated right atrium (RA) and a right ventricle (RV). Electroanatomical mapping of the RA showed extensive scarring with no recordable electrical potentials. Although she had frequent premature ventricular contractions, neither spontaneous ventricular tachycardia (VT) nor induced VT was observed. Microscopic examination of the RV indicated fibrofatty myocardium. Atrial arrhythmias associated with SSS may be the cause of symptoms in some cases of ARVC.  相似文献   
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