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21.
Sato M  Kikuchi T  Asazuma T  Yamada H  Maeda H  Fujikawa K 《Spine》2001,26(24):2653-2660
STUDY DESIGN: With the heterogeneity of the intervertebral disc as the focus, intervertebral discs from normal young rabbits were separated into nucleus pulposus (NP), inner anulus fibrosus (IAF), and outer anulus fibrosus (OAF) zones. Disc cells from each zone were isolated and propagated under monolayer and within agarose gel culture. The metabolism of these cultured disc cells was examined in terms of glycosaminoglycan (GAG) accumulation. OBJECTIVES: The object was to study the metabolism of disc cells derived from each zone and characterize them on the basis of GAG accumulation and composition. SUMMARY OF BACKGROUND DATA: It has been shown that three-dimensional culture systems, such as within-agarose gels or in alginate beads, permit long-term maintenance of the articular chondrocyte phenotype in vitro. However, little has been reported on how the metabolism of intervertebral disc cells, especially GAG accumulation, is affected by different culture conditions. METHODS: Cells from each zone were subjected to monolayer or three-dimensional culture for up to 12 days. GAG accumulation in the different culture systems was analyzed using chemical, histologic, and immunohistologic methods. Differences of GAG and DNA content among NP, IAF, and OAF cells were statistically evaluated by analysis of variance. The data of keratin sulfate content in three-dimensional culture were compared with that in monolayer culture using nonparametric Mann-Whitney U test. RESULTS: Monolayer culture revealed that increases in GAG content were significantly higher in IAF cells than in OAF cells. However, in three-dimensional culture GAG content was similar in the two groups. AF cells in three-dimensional cultures showed immunohistochemical localization of chondroitin sulfate and keratan sulfate, suggesting the existence of pericellular matrix. High performance liquid chromatography confirmed the expression of keratan sulfate in cultured cells. CONCLUSIONS: GAG accumulation in cultures of cells from different zones of the intervertebral disc varied according to the culture conditions used. The importance of choosing the appropriate culture systems to meet the objectives of a study should be emphasized.  相似文献   
22.
Macrophage-colony stimulating factor (M-CSF) is an essential requirement for human osteoclast formation, but its effect on the proliferation and differentiation of circulating osteoclast precursor cells is unknown. Other growth factors and cytokines are also known to support/stimulate osteoclast formation from mouse marrow precursors, but it is not certain whether these factors similarly influence human osteoclast formation. In this study, human monocytes were cocultured with osteoblast-like UMR-106 cells on coverslips and dentine slices for up to 21 days in the presence of 1,25 dihydroxyvitamin D(3) (10(-7) mol/L), dexamethasone (10(-8) mol/L), and various concentrations of either M-CSF or other humoral factors (interleukin [IL]-1beta, IL-3, IL-6, and IL-11; tumor necrosis factor-alpha [TNF-alpha]; and granulocyte macrophage [GM]-CSF). The effect on osteoclast formation was assessed by tartrate-resistant acid phosphatase (TRAP) and vitronectin receptor staining and lacunar bone resorption. The results of time-course and proliferation studies showed that M-CSF stimulated both the proliferative and differentiation stages of human osteoclast formation from circulating osteoclast precursors in a dose-dependent manner. A high concentration of M-CSF (100 ng/mL) did not inhibit osteoclast formation. IL-3 and GM-CSF were also capable of stimulating human osteoclast formation, although these growth factors were much less potent than M-CSF. IL-3- and GM-CSF-stimulated osteoclast formation was inhibited by an antibody specific for human M-CSF. Osteoclast formation and lacunar resorption was not seen when either TNF-alpha, IL-1beta, IL-6 (+ soluble IL-6 receptor), or IL-11 was substituted for M-CSF during coculture. These results confirm that M-CSF is essential for human osteoclast formation from circulating mononuclear precursors, and also shows that IL-3 and GM-CSF may support osteoclast differentiation via the stimulation of M-CSF production by human monocytes.  相似文献   
23.

Purpose

Preventing a recurrence of Crohn’s disease is a problem that remains to be solved. We evaluated the impact of using infliximab as a postoperative therapy on preventing the surgical recurrence of Crohn’s disease.

Methods

We performed a pair-matched study comparing 100 patients who had received postoperative infliximab maintenance therapy with those who had not between 1995 and 2010. The patients were matched by gender, Vienna classification and age at the time of the operation. Crohn’s disease-related reoperation was evaluated as surgical recurrence.

Results

In the postoperative infliximab maintenance therapy group, infliximab was administrated within 8 weeks after the operation. The median follow-up period was 36 months in the postoperative infliximab maintenance therapy group and 51 months in the control group. Surgical recurrences were recognized in 37 patients (three in the postoperative infliximab maintenance therapy group and 34 in the control group). A univariate analysis by the Kaplan–Meier method identified a body mass index >18 at the time of the operation (HR 0.19, p = 0.01) and postoperative infliximab maintenance therapy (HR 0.22, p = 0.0022) as factors related to the reduction of surgical recurrence. The multivariate analysis revealed that postoperative infliximab maintenance therapy was the only significant factor preventing surgical recurrence.

Conclusion

Postoperative infliximab maintenance therapy for Crohn’s disease prevents surgical recurrence, at least within 3 years after the operation.  相似文献   
24.
Spontaneous massive retroperitoneal hemorrhage from an adrenal tumor is rare and is usually fatal if unrecognized. We report a case of spontaneous rupture of a primary adrenocortical carcinoma that occurred in a 79-year-old man. He visited our hospital with left abdominal pain. Computed tomography (CT) showed a left retroperitoneal hemorrhage. We could not find the origin of this hemorrhage. Two months later, CT showed the left adrenal tumor, and left adrenalectomy and nephrectomy were performed successfully. The histological diagnosis was adrenocortical carcinoma. He rejected adjuvant therapy. Local recurrence of the tumor was found, and right adrenal gland, brain, and mediastinal lymph node metastases were recognized 6 months after the operation. He died 11 months after the operation.  相似文献   
25.
Background/Purpose: Recent studies have found that anomalous pancreaticobiliary ductal union (APBDU) is a substantial risk factor for biliary tract cancer at a younger age. DPC-4 (Smad-4) is a new tumor suppressor gene frequently inactivated in pancreatic and bile duct adenocarcinoma. To clarify carcinogenesis in APBDU, the authors investigated possible DPC-4 and K-ras mutations in 35 pediatric patients. Methods: DNA was extracted from biliary tract epithelial cells, which were resected surgically and histologically purified using microdissection. Polymerase chain reaction (PCR) primers were designed specifically for exons 8-11 of DPC-4 (18q21.1) and exons 1-2 of the K-ras oncogene (12p12.1). DNA sequences were determined using the direct DyeDeoxy Terminator Cycle method. Results: Of 35 children, 30 had wild-type DPC-4 and K-ras genes. K-ras mutations were detected in 5 patients, 4 of whom showed epithelial hyperplasia or metaplasia. In a 12-year-old girl with adenocarcinoma arising from a choledochal cyst, K-ras and DPC-4 (homozygous deletion) mutations were identified simultaneously. Conclusions: These results suggest that carcinogenesis in the biliary tract epithelium in APBDU is accompanied by multistep genetic mutational events; K-ras gene mutation occurs early in epithelial hyperplasia or metaplasia, whereas inactivation of the DPC-4 gene accumulates late in the progression of biliary tract adenocarcinoma. J pediatr Surg 38:694-697. [copy ] 2003 Elsevier Inc. All rights reserved.  相似文献   
26.
BACKGROUND: To clarify the pathology of the development of prostatic disorders such as inflammation, cancer, and hyperplasia, we compared histopathological findings of the prostate according to age group. METHODS: Whole-mount sections of prostates were used to assess the relationship between age and prostate weight (n=962), prostate histological composition in the transition zone (TZ) and in the peripheral zone (PZ) (n=68), prostate histopathological findings by zone (n=102), and comparison of latent tumor development by age group (n=1,815). RESULTS: A rapid increase in prostate weight from birth to the 20s was followed by a slow rise thereafter. Volume increases (P<0.01) were observed in all components of glandular epithelium, glandular lumen, and stroma in the TZ from the 40s to 70s inclusive. In the PZ, the epithelial and stromal volumes tended to decrease in an age-dependent manner (P<0.05). Calculi and lymphocyte infiltration were detected at a relatively early age, with a tendency towards an age-dependent increase. Glandular dilation and nodular hyperplasia were noted first in the 30s group, also with a tendency towards age-dependent increase. Latent tumors were first detected in the 30s group (5.6%), and slowly increased thereafter. CONCLUSIONS: There was an age-dependent trend towards prostate glandular dilation and prostate enlargement with inflammation. It was demonstrated that tumor and hyperplasia have a long natural history, usually starting in the fourth decade of life, accompanied by dynamic changes with age in glandular tissue composition as well as cell proliferation activity.  相似文献   
27.

Background/Purpose

Recent biological studies have elucidated the molecular mechanism of muscle development, in which various regulatory factors (myogenic regulatory factors [MRFs]) play key roles during embryogenesis. To investigate the development of anorectal malformations (ARMs), we studied MRF expressions in myogenic cells in the pelvic floor using murine embryos affected with ARM.

Methods

Anorectal malformation embryos were obtained from the 10.5th embryonal day (E10.5) to the 7.0th postnatal day (D7.0) in a natural mutant strain (Sd/+, RSV/Le). Serial frozen sections were prepared for immunohistochemistry using specific antibodies to M-cadherin, myoD, Myogenin, myosin heavy chain, and alfa-actin molecule.

Results

In normal mice, embryonal caudal somites differentiated into myogenic stem cells and migrated to the pelvic floor between E11.0 and E14.0. In the ARM mice, however, caudal somites were irregularly arranged and MRF expressions in myogenic cells were markedly decreased in the dorsocaudal region at E11.5 to E13.0, leading to hypoplastic pelvic floor muscles.

Conclusions

The maldevelopment of pelvic floor muscles in ARM is derived from a deficient supply of myogenic stem cells, with impaired MRF expression. These results suggest that myogenic stem cells, available from bone marrow contents, may be used for postnatal muscle regeneration to reinforce the pelvic floor muscle function in children with ARM.  相似文献   
28.

Background/Purpose

Tethered spinal cord is frequently associated with anorectal malformations (ARMs). However, it remains unknown how the tethered spinal cord develops and relates to the severity of ARM. We studied the development of the spinal cord in ARM mouse embryos induced by all-trans retinoic acid (ATRA).

Methods

Pregnant ICR-Slc mice were administered 100 mg/kg of ATRA on the ninth embryonic day (E9.0). Embryonic specimens were obtained from the uteri between E11.0 and E18.5. Midsagittal histologic sections focusing on the spinal cord and pelvis were prepared for immuonhistochemistry specific for neurofilament and Protein Gene Product 9.5 molecules.

Results

More than 98% of ATRA-treated embryos demonstrated ARM with rectourethral or rectocloacal fistula. Normal embryos exhibited progressive ascent of the spinal cord from E14.5. However, in ARM embryos, the distal spinal cord ended with meningomyelocelelike or atypical hamartomatous lesions at E11.5 to E13.5, which later caused stretch force that damaged the spinal cord, resulting in tethered cord between E16.0 and E16.5.

Conclusions

In ATRA-induced ARM mouse embryos, tethered spinal cord was mostly established, accompanied by caudal neural maldevelopment, during early fetal development. This experimental model may be useful for researching detailed neuropathologic conditions in ARM children accompanied with tethered spinal cord.  相似文献   
29.
A 58-year-old man with a left renal stone and with poor controlled hypertension was attacked by sudden onset of left renal colic pain, gross hematuria and nausea at 3 hours after ESWL. Ultrasonography and enhanced computed tomography revealed severe subcapsular hematoma, which compressed the left kidney. Since serum hemoglobin level continued to decrease in spite of 7 days of conservative therapy, we performed transfusion of red blood cells and selective transarterial embolization (TAE). Renal angiography showed multiple pseudo-aneurysms of arteriole at the lower pole of the left kidney. Embolization of left renal artery was effective to relieve patient's symptom and to stabilize the serum hemoglobin level.  相似文献   
30.
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