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91.
Islet-cell hyperplasia causing hyperinsulinemic hypoglycemia in an adult   总被引:2,自引:0,他引:2  
We report a patient, a 23-year-old man, who had clinical and laboratory findings suggestive of insulinoma. Although imaging studies did not reveal any tumors in the pancreas, distal pancreatectomy was performed because the possibility of small insulinoma could not be completely excluded. Grossly, the surgically removed pancreas did not reveal any tumors. Microscopically, the pancreas exhibited islet cell hyperplasia and nesidioblastosis. To our knowledge, this is the first authentic reported case of islet-cell hyperplasia occurring in a Japanese adult. Received Mar. 4, 1997; accepted May 23, 1997  相似文献   
92.
The clinical features of familial Creutzfeldt-Jakob disease with a codon 200 point mutation [fCJD (E200K)] are similar to those of sporadic CJD (sCJD). MRI diffusion-weighted imaging (MRI-DWI) has been reported to be useful for the early diagnosis of CJD. We describe a Japanese fCJD (E200K) case in which thalamic symptoms were the initial manifestations. On admission, electroencephalography (ECG) showed no periodic synchronous discharge (PSD), and MRI showed no abnormalities. However, single photon emission computed tomography (SPECT) using (99m)Tc-ethyl cysteinate dimer ((99m)Tc-ECD) revealed hypoperfusion in the right thalamus. We conclude that the thalamic form of CJD tends to show no high-intensity area (HIA) by MRI-DWI, and that SPECT may be more useful for visualizing the affected area responsible for the thalamic symptoms at an early stage.  相似文献   
93.
BACKGROUND: Acute asthma often requires expensive emergency department visits and hospitalizations, especially among economically disadvantaged inner-city adults. However, few studies have examined approaches for improving acute asthma care in this population. METHODS: We conducted a cohort study involving patients who were discharged from a public hospital emergency department following acute asthma care between March 31, 1997, and August 5, 1999, to identify processes of care effective for improving peak expiratory flow rate at a 2- to 3-week follow-up. Adult patients who met the predetermined criteria for asthma, who underwent a baseline peak expiratory flow rate reading, and who did not have concurrent acute sinusitis or pneumonia were eligible (N = 448). Of the 365 patients enrolled in the study, 309 (84.7%) completed it. We used a multiple linear regression analysis adjusted for patient risk to assess the association between acute asthma care processes derived from the National Asthma Education Prevention Program guidelines (inhaled beta2-agonists, inhaled corticosteroids, systemic corticosteroids, asthma care follow-up, and patient asthma education) and percentage peak expiratory flow rate change at follow-up. RESULTS: Systemic corticosteroids had a significant effect for increasing percentage peak expiratory flow rate change at the 2- to 3-week follow-up for all asthma exacerbation severity levels (beta = 26.1; 95% confidence interval, 1.8-50.5; P =.04) and severity levels specified by the National Asthma Education Prevention Program guidelines (beta = 31.6; 95% confidence interval, 8.1-55.1; P =.01). CONCLUSION: Outpatient systemic corticosteroids were effective for improving lung function 2 to 3 weeks after acute asthma care, and their use should reduce asthma-related morbidity, especially among economically disadvantaged inner-city adults.  相似文献   
94.

Background/Purpose

It has been reported that circulating tumor cells (CTCs) can be used to predict survival in metastatic breast cancer. In this preliminary study, we examined the level of CTCs in pancreatic cancer (PC) patients to elucidate whether we could predict survival in PC.

Methods

The eligible subjects, at Tokyo Medical University Hospital, were 26 patients with PC, 11 with chronic pancreatitis, and 10 healthy volunteers. Three PC patients underwent surgery, 18 patients (who were stage IV) were treated with gemcitabine (GEM), and 5 patients received best supportive care (BSC).

Results

The CTC count was 1/7.5 ml blood or higher (defined as positive) in 11 of the 26 patients (42%; mean, 16.9/7.5 ml blood; range, 1-105/7.5 ml blood). Gemcitabine was administered to 6 of the 11 CTC-positive patients (3.8 courses on average). The treatment was continued for more than three courses in 2 patients, in both of whom the CTC count was only 1/7.5 ml blood. Operation was performed in 1 of the 11 CTC-positive patients. The remaining 4 patients of the 11 CTC-positive patients received only BSC. CTC was negative in 15 patients with PC (stage II, 1; stage III, 1; stage IVa, 7; and stage IVb, 6) and in the subjects with benign conditions. The median survival times (MSTs) of the CTC-positive and-negative patients were 110.5 and 375.8 days (P < 0.001). When the analysis was limited to the 14 stage-IVb patients, the MSTs of the CTC-positive and-negative patients were 52.5 and 308.3 days (P < 0.01).

Conclusions

The present study demonstrated that the detection of CTCs in peripheral blood may be useful to predict prognosis in patients with PC.  相似文献   
95.
We previously found that cancer metastasis is accelerated by immunosuppression during Snail-induced epithelial-to-mesenchymal transition (EMT). However, the molecular mechanism still remained unclear. Here, we demonstrate that CCL2 is a critical determinant for both tumor metastasis and immunosuppression induced by Snail+ tumor cells. CCL2 is significantly upregulated in various human tumor cells accompanied by Snail expression induced by snail transduction or TGFβ treatment. The Snail+ tumor-derived CCL2 amplifies EMT events in other cells including Snail? tumor cells and epithelial cells within tumor microenvironment. CCL2 secondarily induces Lipocalin 2 (LCN2) in the Snail+ tumor cells in an autocrine manner. CCL2 and LCN2 cooperatively generate immunoregulatory dendritic cells (DCreg) having suppressive activity accompanied by lowered expression of costimulatory molecules such as HLA-DR but increased expression of immunosuppressive molecules such as PD-L1 in human PBMCs. The CCL2/LCN2-induced DCreg cells subsequently induce immunosuppressive CD4+FOXP3+ Treg cells, and finally impair tumor-specific CTL induction. In murine established tumor model, however, CCL2 blockade utilizing the specific siRNA or neutralizing mAb significantly inhibits Snail+ tumor growth and metastasis following systemic induction of anti-tumor immune responses in host. These results suggest that CCL2 is more than a chemoattractant factor that is the significant effector molecule responsible for immune evasion of Snail+ tumor cells. CCL2 would be an attractive target for treatment to eliminate cancer cells via amelioration of tumor metastasis and immunosuppression.  相似文献   
96.
ObjectiveRebleeding of aneurysmal subarachnoid hemorrhage (aSAH) is one of the significant risk factors for poor clinical outcome. The rebleeding risk is the highest during the acute phase with an approximate rebleeding rate of 9-17% within the first 24 h. Theoretically, general anesthesia can stabilize a patient's vital signs; however, its effectiveness as initial management for preventing post-aSAH rebleeding remains unclear. The purpose of this study was to determine the feasibility and safety of ultra-early general anesthesia induction for reducing the rebleeding rates among patients with aSAH.Materials and methodsWe retrospectively evaluated patients with aSAH who were admitted to our department between January 2013 and December 2019. All the patients underwent ultra-early general anesthesia induction as initial management regardless of their severity. We evaluated the rebleeding rate before definitive treatment, factors influencing rebleeding, and general anesthesia complications.ResultsWe included 191 patients with two-third of them having a poor clinical grade (World Federation of Neurological Society [WFNS] grade IV or V). The median duration from admission to general anesthesia induction was 22 min. Rebleeding before definitive treatment occurred in nine patients (4.7%). There were significant differences in the Glasgow Coma Scale score (p = 0.047), WFNS grade (p = 0.02), and dissecting aneurysm (p <0.001) between the rebleeding and non-rebleeding patients. There were no cases of unsuccessful tracheal intubation or rebleeding during general anesthesia induction.ConclusionUltra-early general anesthesia induction could be performed safely in patients with aSAH, regardless of the WFNS grade; moreover, it resulted in lower rebleeding rate than that reported in previous epidemiological reports.  相似文献   
97.
Vesicles or micelles prepared from amphiphiles with azobenzene (Az) moieties and long alkyl chains have attracted much attention in drug delivery systems. To induce release behavior from smart carriers via transcis photoisomerization of the Az groups, UV light exposure is typically used, but it can damage DNA and hardly penetrates cells. In this paper, Az-containing phospholipids without long alkyl tails were designed and synthesized; in these compounds, the end group of the Az moiety was substituted with a –NO2 and –OCH3 group (abbreviated N6 and M6, respectively). N6 self-assembled into H-aggregates with an interdigitated bilayered structure in water through the antiparallel orientation due to π–π interactions of the Az group, the attractive van der Waals forces, and the interactions and bending behavior of the phosphocholine groups. Vesicles showing visible light stimuli-responsive behavior were obtained by mixing N6 and M6, and the release of encapsulated calcein was triggered by visible light.

A mixture of a nitro- and methoxy-substituted azo-containing phospholipids without long alkyl tails formed vesicles showing visible light stimuli-responsive behavior. Release of encapsulated calcein from the vesicles was triggered by visible light.  相似文献   
98.
Although rapidly growing non-tuberculosis mycobacterium can occasionally cause postoperative infections, Mycobacterium neoaurum is a rare pathogen of surgical site infection. We report a case of pin tract infection caused by M. neoaurum in a 14-year-old girl who was admitted for lengthening of her right fourth metatarsal bone. Pain, redness, and exudate were observed 18 days after external fixator insertion. Repeated exudate cultures revealed M. neoaurum, and she was diagnosed with a mycobacterial pin tract infection. She was initially administered intravenous ciprofloxacin and minocycline, and then was switched to oral trimethoprim-sulfamethoxazole and minocycline for a total of 6 months. Despite the pin tract infection, bone lengthening was completed under antibiotic treatment without removal of the pin; no other complications were noted. There are no prior reports of external fixator pin tract infection by M. neoaurum. While such cases may be rare, this case demonstrates that bone distraction may still be successfully completed using appropriate antibiotic therapy without pin removal.  相似文献   
99.
Dwarfism and early death in mice lacking C-type natriuretic peptide   总被引:11,自引:0,他引:11       下载免费PDF全文
Longitudinal bone growth is determined by endochondral ossification that occurs as chondrocytes in the cartilaginous growth plate undergo proliferation, hypertrophy, cell death, and osteoblastic replacement. The natriuretic peptide family consists of three structurally related endogenous ligands, atrial, brain, and C-type natriuretic peptides (ANP, BNP, and CNP), and is thought to be involved in a variety of homeostatic processes. To investigate the physiological significance of CNP in vivo, we generated mice with targeted disruption of CNP (Nppc(-/-) mice). The Nppc(-/-) mice show severe dwarfism as a result of impaired endochondral ossification. They are all viable perinatally, but less than half can survive during postnatal development. The skeletal phenotypes are histologically similar to those seen in patients with achondroplasia, the most common genetic form of human dwarfism. Targeted expression of CNP in the growth plate chondrocytes can rescue the skeletal defect of Nppc(-/-) mice and allow their prolonged survival. This study demonstrates that CNP acts locally as a positive regulator of endochondral ossification in vivo and suggests its pathophysiological and therapeutic implication in some forms of skeletal dysplasia.  相似文献   
100.
The structure of a partially deuterated rubredoxin from the hyperthermophilic archaeon Pyrococcus furiosus, an organism that grows optimally at 100 degrees C, was determined by using the neutron single-crystal diffractometer dedicated for biological macromolecules (BIX-3) at the JRR-3M reactor of the Japan Atomic Energy Research Institute. Data were collected at room temperature up to a resolution of 1.5 A, and the completeness factor of the data set was 81.9%. The model contains 306 H and 50 D atoms. A total of 37 hydration water molecules were identified, with 15 having all three atoms fully located and the remaining D2O molecules partially defined. The model has been refined to final agreement factors of R = 18.6% and Rfree = 21.7%. Several orientations of the O-D bonds of side chains, whose assignments from x-ray data were previously ambiguous, were clearly visible in the neutron structure. Although most backbone N-H bonds had undergone some degree of H/D exchange throughout the rubredoxin molecule, 5 H atom positions still had distinctly negative (H) peaks. The neutron Fourier maps clearly showed the details of an extensive set of H bonds involving the ND3+ terminus that may contribute to the unusual thermostability of this molecule.  相似文献   
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