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101.
Chemical carcinogens, such as chloroform and trichloroethylene, are present in drinking water in Japan. As these contaminants are believed to have a role in carcinogenesis, we examined if chloroform and trichloroethylene, as well as methylene chloride, xylene, benzene, and ethanol, have the ability to generate hydrogen peroxide (H2O2) in human polymorphonuclear leukocytes (PMN) and human leukemia (HL-60) cells. Methylene chloride, benzene, xylene, trichloroethylene, and ethanol did not increase cellular H2O2: production as measured by flow cytometry nor as observed by confocal laser microscopy. In PMN and RAuntreated HL-60 cells chloroform did not significantly affect H2O2 levels. However, in HL-60 cells sensitized by pretreatment of 10 nM retinoic acid (RA) for 12 h, chloroform induced a significant increase in H2O2, but the increase induced by trichloroethylene was not significant. The observed increase in fluorescence was confirmed using a confocal laser microscope. These results indicate that chloroform and trichloroethylene may stimulate H2O2 production in HL60 cells sensitized by pretreatment of RA. Our method may be useful to test if weak stimulants can stimulate intracellular H2O2 production.  相似文献   
102.
The purple-flesh potato (Solanum tuberosum L.) cultivar “Shadow Queen” (SQ) naturally contains anthocyanins. This randomized, double-blind, placebo-controlled study determines whether ingesting purple potatoes increases the number of mesenchymal stem cells (MSC) and improves stress response, a minor health complaint in healthy adults (registration number: UMIN000038876). A total of 15 healthy subjects (ages: 50–70 years) with minor health complaints were randomly assigned to one of two groups. For 8 weeks, the placebo group received placebo potatoes cv. “Haruka” and the test group received test potato cv. SQ containing 45 mg anthocyanin. The MSC count and several stress responses were analyzed at weeks 0 and 8 of the intake periods. The ingestion of a SQ potato did not affect the MSC count but markedly improved psychological stress response, irritability, and depression as minor health complaints compared with “Haruka”. No adverse effects were noted. Hence, an 8-week intake of SQ could improve stress responses.  相似文献   
103.
The purpose of this study was to determine the outcomes and optimal practice patterns of definitive radiotherapy for primary vaginal cancer. Between 1993 and 2012, 49 patients were treated with definitive radiotherapy for primary vaginal cancer in three hospitals. Of these, 15 patients (31%) had clinically positive regional lymph node metastasis. A total of 34 patients (70%) received external beam radiotherapy with high-dose-rate brachytherapy (interstitial or intracavitary), and 8 (16%) (with small superficial Stage I tumors) were treated with local radiotherapy. The median follow-up was 33 months (range: 1–169 months). The 3-year overall survival (OS), disease-free survival (DFS), and loco-regional control (LRC) rates were 83%, 59% and 71%, respectively. In multivariate analysis, the histological type (P = 0.044) was significant risk factors for LRC. In Federation of Gynecology and Obstetrics (FIGO) Stage I cases, 3 of 8 patients (38%) who did not undergo prophylactic lymph node irradiation had lymph node recurrence, compared with 2 of 12 patients (17%) who underwent prophylactic pelvic irradiation. For Stage III–IV tumors, the local recurrence rate was 50% and the lymph node recurrence rate was 40%. Patients with FIGO Stage I/II or clinical Stage N1 had a higher recurrence rate with treatment using a single modality compared with the recurrence rate using combined modalities. In conclusion, our treatment outcomes for vaginal cancer were acceptable, but external beam radiotherapy with brachytherapy (interstitial or intracavitary) was needed regardless of FIGO stage. Improvement of treatment outcomes in cases of FIGO Stage III or IV remains a significant challenge.  相似文献   
104.
Background and HypothesisMachine learning approaches using structural magnetic resonance imaging (MRI) can be informative for disease classification; however, their applicability to earlier clinical stages of psychosis and other disease spectra is unknown. We evaluated whether a model differentiating patients with chronic schizophrenia (ChSZ) from healthy controls (HCs) could be applied to earlier clinical stages such as first-episode psychosis (FEP), ultra-high risk for psychosis (UHR), and autism spectrum disorders (ASDs).Study DesignTotal 359 T1-weighted MRI scans, including 154 individuals with schizophrenia spectrum (UHR, n = 37; FEP, n = 24; and ChSZ, n = 93), 64 with ASD, and 141 HCs, were obtained using three acquisition protocols. Of these, data regarding ChSZ (n = 75) and HC (n = 101) from two protocols were used to build a classifier (training dataset). The remainder was used to evaluate the classifier (test, independent confirmatory, and independent group datasets). Scanner and protocol effects were diminished using ComBat.Study ResultsThe accuracy of the classifier for the test and independent confirmatory datasets were 75% and 76%, respectively. The bilateral pallidum and inferior frontal gyrus pars triangularis strongly contributed to classifying ChSZ. Schizophrenia spectrum individuals were more likely to be classified as ChSZ compared to ASD (classification rate to ChSZ: UHR, 41%; FEP, 54%; ChSZ, 70%; ASD, 19%; HC, 21%).ConclusionWe built a classifier from multiple protocol structural brain images applicable to independent samples from different clinical stages and spectra. The predictive information of the classifier could be useful for applying neuroimaging techniques to clinical differential diagnosis and predicting disease onset earlier.  相似文献   
105.

Background

To investigate the expression of parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor 1 (PTH1R) in clinical specimens of normal and diseased bladders. PTHrP is a unique stretch-induced endogenous detrusor relaxant that functions via PTH1R. We hypothesized that suppression of this axis could be involved in the pathogenesis of bladder disease.

Methods

PTH1R expression in clinical samples was examined by immunohistochemistry. Normal kidney tissue from a patient with renal cancer and bladder specimens from patients undergoing ureteral reimplantation for vesicoureteral reflux or partial cystectomy for urachal cyst were examined as normal control organs. These were compared with 13 diseased bladder specimens from patients undergoing bladder augmentation. The augmentation patients ranged from 8 to 31 years old (median 15 years), including 9 males and 4 females. Seven patients had spinal disorders, 3 had posterior urethral valves and 3 non-neurogenic neurogenic bladders (Hinman syndrome).

Results

Renal tubules, detrusor muscle and blood vessels in normal control bladders stained positive for PTH1R. According to preoperative urodynamic studies of augmentation patients, the median percent bladder capacity compared with the age-standard was 43.6% (range 1.5–86.6%), median intravesical pressure at maximal capacity was 30 cmH2O (range 10–107 cmH2O), and median compliance was 3.93 ml/cmH2O (range 0.05–30.3 ml/cmH2O). Detrusor overactivity was observed in five cases (38.5%). All augmented bladders showed negative stainings in PTH1R expression in the detrusor tissue, but positive staining of blood vessels in majority of the cases.

Conclusions

Downregulation of PTH1R may be involved in the pathogenesis of human end-stage bladder disease requiring augmentation.  相似文献   
106.
Summary Behaviour and fate of the transplanted articular cartilage were studied in 180 adult rabbits, using the scanning electron microscope, histological staining and autoradiographic examination.The junction between the host cartilage and the transplanted cartilage was covered with thin connective tissue layers which extended from the edges 4 weeks after transplantation.After the 24th week of transplantation the cartilage tissue appeared to be degenerating at the periphery of the graft.However, in the middle portion of the graft surviving cartilage cells were observed using 35S autoradiography.
Résumé Comportement et évolution du cartilage articulaire transplanté ont été étudiés chez 180 lapins adultes par microscopie électronique, colorations histologiques et autoradiographies.Quatre semaines après la transplantation, une fine couche de tissue conjonctif qui s'étend depuis les bords recouvre la jonction entre le cartilage du receveur et le cartilage transplanté.Vingt-quatre semaines après la transplantation, le tissu cartilagineux commence à dégénérer à la périphérie du greffon. Cependant, à la partie centrale de celuici, des cellules cartilagineuses survivantes peuvent être mises en évidence grâce à l'autoradiographie au S35.
  相似文献   
107.
Yoshino O  Quail A  Oldmeadow C  Balogh ZJ 《Injury》2012,43(2):169-173
IntroductionThe importance of the abdominal wall characteristics in intraabdominal pressure (IAP), intraabdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are poorly understood. The applicability of laboratory research findings to human scenarios is unknown due to the potential differences in abdominal wall elastance (AWE) amongst species. The aims of the study are to describe the AWE curve in rabbits and to compare it to the available human data.Materials and methodsProspective experimental animal study in the setting of research laboratory. Male New Zealand White rabbits weighting 2.7 kg ± 0.1 kg, were anesthetized and the AWE was determined by infusion of lactated Ringer's solution into the peritoneal cavity whilst the IAP was measured. A meta-analysis of peer-reviewed studies was conducted to define human AWE.ResultsThe described AWE was lower in the rabbit than in humans. The function comparing human and rabbit was: loge human IAP = (0.58 loge rabbit IAP + 1.6).ConclusionsThe AWE can vary amongst species. This study determined the relationship to allow the comparison of rabbit and human IAP. The proposed mathematical function is important for the advancement of interpretation and understanding of animal research into IAH and ACS. We recommend developing model-specific functions comparing individual animal models’ IAP and that of humans.  相似文献   
108.

Background

Laparoscopic splenic vessel-preserving distal pancreatectomy (lap-SVPDP) is a popular procedure in pancreatic surgery. However, postoperative complications include false aneurysms of the splenic artery, splenic vein stenosis and thrombosis, pancreatic fistulas, abscess, and perigastric varices.

Methods

Eight patients (three men, five women, average age 66.1 years) with benign tumors underwent lap-SVPDP. Lap-SVPDP was performed in the lithotomy position with the head slightly elevated. The splenic vein was peeled longitudinally toward the pancreatic tail. A vessel-sealing system was used to detach the pancreatic body from the greater omentum, and the pancreas was transected using a surgical stapler.

Results

Mean operation time was 254 min; mean blood loss was 163 ml; and mean post-surgical hospitalization time was 13 days. No postoperative bleeding from the preserved splenic vessels occurred, and there were no splenic infarcts or splenic abscesses.

Conclusions

For safe performance of lap-SVPDP, the posterior surface of the pancreas should be completely exposed. The splenic vein should be ‘peeled away’, starting from its central rear, enabling easy detection of its course to avoid inadvertent sealing. With improved operational techniques, lap-SVPDP can be adopted as a standard procedure in pancreatic surgery.  相似文献   
109.
Miura H  Taira O  Hiraguri S  Maeda J  Kato H 《Surgery today》2002,32(10):891-895
Squamous cell carcinoma of the breast is a rare type of cancer, the origin of which is still uncertain. We report a case of squamous cell carcinoma of the breast with a recurrent tumor that showed undifferentiated features. The patient was a 55-year-old woman who originally presented with a left breast mass in the upper outer quadrant. Echography showed a 46 × 29 × 23-mm mass with cavity formation, and aspiration cytology confirmed a diagnosis of squamous cell carcinoma. A modified radical mastectomy with level III lymph node dissection was performed. Pathologically, the tumor was composed of squamous cell carcinoma and noninvasive ductal carcinoma. A recurrent tumor showing undifferentiated features was detected in the left forechest 3 months after the operation, and tumorectomy with partial resection of the major and minor pectoralis muscles was performed. Despite intensive therapy including chemotherapy (CEF: cyclophosphamide, epirubicin, 5-fluorouracil) and irradiation (50 Gy), the patient died from pulmonary and skin metastases 20 months after her initial operation. The squamous cell carcinoma of the breast in this patient grew rapidly and her prognosis was poor. Immunohistochemical findings indicated the possibility that the squamous cell carcinoma developed from noninvasive ductal carcinoma of the comedo type, and that the undifferentiated cells from the site of recurrence developed from dedifferentiation of the squamous cell carcinoma. Received: August 10, 2001 / Accepted: March 5, 2002  相似文献   
110.
目的:探索Salacinol全合成的基本步骤。方法:根据Salacinol的结构组成,设计了其结构类似简化物1-(3-磺氧丙基)四氢噻吩锍盐(2)。以四氢噻吩和3-碘基丙醇为原料,经偶合反应和三氧化硫吡啶的酯化制得化合物2。当在相同的条件下以3-碘基丙醇硫酸酯钠替代3-碘基丙醇为烷化剂时,其主要产物经确证为3-碘基丙醇硫酸酯钠的分子内环化物1,4-丙二醇硫酸内酯(7)。结果:上述模拟实验结果提示,通过两步反应制得化合物2的方法可能为Salacinol的全合成提供一种新的途径。  相似文献   
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