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11.

Purpose

The pathogenesis of gastroschisis is unknown. It may be helpful in understanding its pathogenesis to know the structural relationships among umbilical components including umbilical vessels, urachus, and vitelline structures, and thus, the authors investigated the remnants of vitelline structures in a series of cases of gastroschisis.

Methods

Medical records of 41 cases with gastroschisis treated in our institute from 1979 to 2009 were retrospectively reviewed.

Results

Paraumbilical bands, possible remnants of vitelline structures, were observed in 4 cases (9.8%). All 4 bands were attached to the skin edge of the abdominal defect without incorporation into the umbilical cord. The band ended at the mesentery in 3 cases and at the antimesenteric site of the ileum in the remaining case. Histologic findings showed fibrous tissues in all cases. One was possibly associated with the development of colonic atresia. Another was noticed after silo reduction when herniated bowels became strangulated by the band. The other 2 cases were uncomplicated.

Conclusions

Our findings may support the recently proposed hypothesis that the developmental failure of the yolk sac and related vitelline structures to merge with or to be incorporated into the umbilical stalk might be associated with the pathogenesis of the abdominal wall defect in gastroschisis. Paraumbilical bands derived from vitelline structures may possibly cause intestinal ischemia prenatally or postnatally.  相似文献   
12.
Choroid plexus ependymal cells host neural progenitor cells in the rat   总被引:2,自引:0,他引:2  
We previously demonstrated that choroid plexus epithelial (modified ependymal) cells (CPECs) differentiated into astrocytes after grafting into the spinal cord. In the present study, we examined whether CPECs from rats at postnatal 1 day (P1), 7 day (P7), and 8 weeks (P8W) can function as neural progenitor cells that give rise to neurons and glial cells. Cell spheres were produced in cultures of whole tissue of the choroid plexus from the fourth ventricle of rats at each postnatal period. beta-tubulin class III (Tuj-1), glial fibrillary acid protein (GFAP)-, and O4-positive cells differentiated from cell spheres in the differentiation medium. We produced a monoclonal antibody 3E6 specifically labeling microvilli of CPECs. Using this monoclonal antibody, CPECs were isolated from the choroid plexus of P8W rats by cell sorter (FACS). Immunocytochemistry confirmed that there was no contamination from fibroblasts, endothelial cells, macrophages, or Schwann cells in the FACS-isolated 3E6-labeled cells. Cell spheres formed in the cultures of these 3E6-labeled CPECs. After expansion, these cell spheres gave rise to Tuj-1- (5%), GFAP- (45%), and O4-positive cells (0.16%). The remaining cells (45%) were unlabeled neural or glial markers. Some CPECs of the P8W rat were immunohistochemically stained with lineage-associated markers of Musashi-1 and epidermal growth factor-receptor (EGF-R). In addition, infusion of EGF or fibroblast growth factor-2 (FGF2) into the ventricle increased the number of bromodeoxyuridine (BrdU)-positive cells among CPECs from 0.03% (untreated) to 1.14% (38-fold, EGF) and 1.03% (35-fold, FGF2), respectively. These findings indicate that neural progenitor cells exist among CPECs in the rat.  相似文献   
13.
Human pluripotent embryonic stem cells (hESCs) have great promise for research into human developmental biology, development of cell therapies for the treatment of diseases, toxicology, and drug discovery. Traditionally, undifferentiated hESCs are maintained on mouse embryonic fibroblasts (MEFs), which impede the clinical applications of hESCs. Here we have examined the long-term stability of the Japanese hESC line (KhES-1) in feeder-free culture. KhES-1 cells were cultured with MEF conditioned medium (CM) and different doses of basic fibroblast growth factor (bFGF) in six-well-plates of which the surface was coated with Matrigel. KhES-1 cells were maintained for at least 40 passages. In this culture system, the cells maintained stable proliferation rates and steadily expressed Oct-4, Nanog, and alkaline phosphatase. In addition, KhES-1 cells maintained without direct feeder contact formed embryonic bodies with expression of markers from the three germ layers. Here we demonstrated that Japanese human embryonic stem cells KhES-1 were cultured long term in a feeder-free method, while retaining pluripotency in vitro.  相似文献   
14.
We analyzed 8 patients with unresectable locally advanced non-small cell lung cancer who responded to chemotherapy or chemoradiotherapy and underwent complete resection between June 2003 and June 2005. The patients were all male with a mean age of 61 years (range, 42 to 72 years). Histological subtypes included adenocarcinoma in 4 patients and squamous cell carcinoma in 4 patients. Clinical staging included T2N2M0 in 3 patients, T2N3M0 in 2 patients, and 1 patient each for T3N2M0, T4N2M0, and T4N3M0. Preoperative treatment included chemotherapy in 5 patients and chemoradiotherapy in 3 patients, all of whom had a partial response. Surgical procedures included lobectomy in 6 patients and pneumonectomy in 2 patients. In addition, all of the patients underwent mediastinal lymph node dissection (ND2a). Pathological effect included Ef. 0 in 1 patient, Ef. 1 in 2 patients, Ef. 2 in 2 patients, Ef. 3 in 3 patients. The median survival time from initial treatment (or surgery) was 16 (14) months in all cases, 22 (19) for ycN0, 12 (8) for ycN2, 31 (27) for Ef. 3, 13 (9) for Ef. 0-2, 27 (23) for pN0, 13 (9) for pN1-3, 31 (27) for chemoradiotherapy, 16 (13) for chemotherapy, 24 (21) for adenocarcinoma, and 15 (11) for squamous cell carcinoma. Multimodality treatment, including surgery, is beneficial for patients with unresectable locally advanced non-small cell lung cancer who respond to chemotherapy or chemoradiotherapy, especially those patients with ycN0 or pN0.  相似文献   
15.
Background Fractures of the proximal humerus are common and the repair of displaced fractures generally requires an operative approach. In elderly patients, osteoporosis makes internal fixation problematic and frequently contributes to failed fixation and poor clinical results. We have developed a new intramedullary nail (pin lock nail) for the repair of surgical neck fractures of the proximal humerus in patients with osteoporotic bones. A retrospective review is presented of the cases of 19 elderly patients with two-part or three-part fractures of the proximal humerus treated using the pin lock nail. Methods We treated 19 elderly patients with a mean age of 70.5 years. There were 13 two-part surgical neck fractures, 3 two-part surgical neck fractures with non-displaced greater tuberosity fracture, and 3 three-part surgical neck fractures with greater tuberosity fracture. All fractures were treated using the pin lock nail. Clinical results were evaluated using the Japanese Orthopaedic Association score at the last follow-up examination. On radiographic evaluation, duration to bone union of the fracture, backing out of the pin and screw, penetration of the proximal pin, and varus angulations of the humeral neck were examined. Results Mean duration of follow-up was 14 months (range 6–54 months). All fractures had united at an average of 3.3 months after surgery. No backing out of the pin and screw or penetration of the proximal locking pin was seen at the time of last follow-up. Thirteen of the 16 patients had no or minimal varus angulations of the humeral neck (≤10°). The mean overall JOA score was 84.3 points (range 65.5–100). Conclusions Our data show that using the pin lock nail for the treatment of two-part and three-part humeral fractures is a reliable procedure, providing good results with careful postoperative management.  相似文献   
16.
17.
The calcifying cystic odontogenic tumor is a rare benign odontogenic lesion. This report documents a case of this lesion associated with odontoma arising from the anterior maxilla in a 14-year-old boy. The diagnosis was confirmed based on computerized tomography findings, which clearly depicted the internal structures obscured in conventional images.  相似文献   
18.
We report a 71-year-old man who had undergone pylorus-preserving pancreatoduodenectomy (PPPD) using PPPD-IV reconstruction for cholangiocarcinoma. For 6 years thereafter, he had suffered recurrent cholangitis, and also a right liver abscess (S5/8), which required percutaneous drainage at 9 years after PPPD. At 16 years after PPPD, he had been admitted to the other hospital because of acute purulent cholangitis. Although medical treatment resolved the cholangitis, the patient was referred to our hospital because of dilatation of the intrahepatic biliary duct (B2). Peroral double-balloon enteroscopy revealed that the diameter of the hepaticojejunostomy anastomosis was 12 mm, and cholangiography detected intrahepatic stones. Lithotripsy was performed using a basket catheter. At 1 year after lithotripsy procedure, the patient is doing well. Hepatobiliary scintigraphy at 60 minutes after intravenous injection demonstrated that deposit of the tracer still remained in the upper afferent loop jejunum. Therefore, we considered that the recurrent cholangitis, liver abscess, and intrahepatic lithiasis have been caused by biliary stasis due to nonobstructive afferent loop syndrome. Biliary retention due to nonobstructive afferent loop syndrome may cause recurrent cholangitis or liver abscess after hepaticojejunostomy, and double-balloon enteroscopy and hepatobiliary scintigraphy are useful for the diagnosis of nonobstructive afferent loop syndrome.Key words: Nonobstructive afferent loop syndrome, Biliary stasis, Hepaticojejunostomy, Hepatobiliary scintigraphy, Double-balloon enteroscopyIt has been reported that cholangitis occurs in between 6.7% and 14.3% of postoperative pancreatoduodenectomy (PD).1 Most cases of cholangitis originate due to biliary stasis, which is broadly caused by either anastomotic or nonanastomotic stenosis. In many cases, anastomotic stenosis is accompanied by intrahepatic biliary duct dilatation and obstructive jaundice, making early diagnosis and treatment possible.23 On the other hand, nonanastomotic stenosis, including those of afferent loop syndrome, is performed as a conservative treatment for unexplained fever and cholangitis. However, in many cases, the cause remains unidentified, thereby causing this condition to repeat itself. Since cholangitis can at times be fatal, it is therefore important to identify the cause.It has been reported that afferent loop syndrome occurs in around 13% of postoperative PD patients.4 Afferent loop syndrome is generally caused by mechanical occlusion due to the recurrence or metastasis of cancer,46 adhesion,78 torsion,9 internal hernia,10 enterolithiasis,1112 etc., and thereafter, leads to a syndrome associated with acute abdominal symptom or acute cholangitis. On the other hand, nonobstructive afferent loop syndrome may also be caused by biliary stasis due to jejunal motility failure or the length of the blind end or jejunum, and thereafter, leads to acute cholangitis, liver abscess, and the formation of enterolithiasis and intrahepatic stones. Nonobstructive afferent loop syndrome occurs in around 37% of all of the afferent loop syndrome,1213 but few cases have actually been reported.We herein report a rare case in which the patient experienced recurrent cholangitis and liver abscess by biliary stasis due to nonobstructive afferent loop syndrome after pylorus-preserving pancreatoduodenectomy (PPPD) for cholangiocarcinoma.  相似文献   
19.

Background

Renal inulin clearance is the gold standard for evaluation of kidney function, but is compromised by problems of collecting urine samples in children, especially those <6 years or with a bladder dysfunction. Therefore, we should utilize the serum cystatin C (cysC)-based estimated glomerular filtration rate (eGFR) for measuring serum cysC. The purpose of the present study is to determine the applicability of the new serum cysC-based eGFR in Japanese children and adolescents, including infants with chronic kidney disease (CKD), for evaluation of renal function.

Methods

Inulin clearance and standardized serum cysC level determined by the colloidal gold immunoassay were measured in 135 pediatric CKD patients between the ages of 1 month and 18 years with no underlying disease that affects renal function except CKD, to determine serum cysC-based eGFR in Japanese children and adolescents.

Results

We showed the inulin clearance by expression of 1/serum cysC in pediatric CKD patients, which resulted in the equation: inulin GFR (mL/min/1.73 m2) = 104.1 × 1/serum cysC (mg/L) ? 7.80. We also validated the cysC-based eGFR formula for Japanese adults. eGFR values obtained with the adult formula significantly underestimated GFR by approximately 8 % in children with CKD.

Conclusion

We determined the new cysC-based eGFR formula is useful for clinical screening of renal function in Japanese children and adolescents, including infants.  相似文献   
20.

Background

Epidermal growth factor receptor (EGFR) signaling is one of the most promising targets for molecular-targeted therapies in esophageal squamous cell carcinoma (ESCC). Thus, the molecular diagnosis of KRAS and BRAF mutations is clinically important in therapeutic decision making. However, the frequency of KRAS and BRAF mutations in ESCCs remains inconclusive because of the limited sample sizes of previous studies (all N ≤ 80). Pyrosequencing is a nonelectrophoretic nucleotide extension sequencing technology that can be used for mutation testing.

Methods

The frequency of KRAS and BRAF mutations was examined using a nonbiased database of 203 resected ESCCs and a high-throughput pyrosequencing assay.

Results

The validity of the KRAS pyrosequencing method was initially demonstrated by detection of all 4 types of KRAS mutations [c.35G>T (codon 12 GGT>GTT), c.35G>A (codon 12 GGT>GAT), c.34G>T (codon 12 GGT>TGT), c.38G>A mutation (codon 13 GGC>GAC)], which had been previously diagnosed using Scorpion-ARMS technology, in 9 colon cancer tissues (9 of 9; 100 %). Similar results were demonstrated for BRAF mutational status in 3 colon cancer cell lines (HCT116, Colo201, and HT29), which were validated by Sanger dideoxy sequencing. Subsequently, the KRAS mutation was found to be extremely rare (1 of 203; 0.5 %), and the BRAF mutation was absent (0 of 203; 0 %), in the dataset of 203 ESCCs.

Conclusions

These results suggest that KRAS and BRAF mutations play a limited role in the development of ESCC and that mutation analysis is not useful as a screening test for sensitivity to anti-EGFR therapy in ESCC.
  相似文献   
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