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991.
Polymerase chain reaction amplification was used to detect human herpesvirus 6 (HHV-6) DNAs in peripheral blood mononuclear cells (MNCs), plasma, saliva, stool, and urine from three patients with exanthem subitum and in peripheral blood MNCs, plasma, and saliva from their mothers. HHV-6 DNAs were detected in MNCs during and after the disease and were found in plasma only in the acute phase. The virus DNAs were also detected in saliva after recovery from the illness and were found persistently or intermittently in stool but not in urine samples after the onset of the disease. In contrast, one of the three mothers excreted HHV-6 DNAs persistently in saliva. None of the mothers had the virus DNAs in peripheral blood MNCs and plasma nor a significant increase in antibody titers to HHV-6 after possible exposure from their children. These findings suggest systemic replication of HHV-6 during the acute phase in patients with exanthem subitum and persistent infection of the virus in several organs after recovery from the disease. © 1995 Wiley-Liss, Inc.  相似文献   
992.
Polymer adsorbents for chromatographic optical resolution were synthesized by grafting poly(N5-benzyl-L -glutamine-co-γ-benzyl L -glutamyl) onto cross-linked polystyrene beads. The effects of the crosslinking degree (1,5%, 9%, 30%) and the porosity of the polystyrene matrix on the resolution efficiency of the adsorbent were investigated. Similar resolution efficiencies were observed on 1,5% cross-linked gel (non-porous) and 9% cross-linked porous adsorbents, while a decline in the efficiency was observed on 30% cross-linked porous adsorbent. Studies of transmission electron micrographs of these adsorbent clearly showed the effect of degree of crosslinking on the distribution manner of the incorporated poly(α-amino acid). At a degree of 30%, clustered incorporation occurs mainly on the pore surface and not within the cross-linked polymer matrix. Such incorporation manners are also suggested by the swelling properties of the adsorbents. Pore volumes, pore radii, and specific surface areas of the adsorbents were also measured. It was observed that uniform incorporation of poly(α-amino acid) derives a higher resolution efficiency of the adsorbent.  相似文献   
993.
A case of a 69-year-old woman with endometriold adenocarcinoma of the ovary with functioning stromal cells is presented. The patient complained of genital bleeding. Endometrial curettage revealed endometrial hyperplasia. Preoperative levels of serum estradiol and progesterone were elevated, and serum gonadotropin levels were suppressed. The surgical specimen contained fist-sired, bilateral, solid, ovarian tumors and a mildly enlarged uterus. Histologically, the proliferating, atypical, columnar cancer cells resembled early secretory, endometrial epithelial cells with subnuclear vacuolation, and there were clusters of fat-laden foamy cells in the stroma. immunohistochemically, the cancer cells were positive for cytokeratin and progesterone receptor but negative for estrogen receptor. The stromal foamy cells were immunoreactive for vimentin, progesterone receptor, P450 side chain-cleavage, 3β-hydroxysteroid dehydrogenase, and adrenal 4-binding protein. immunoreactivities of P450c-17α hydroxylase and aromatase were only focally observed. These findings indicated that the stromal cells were steroldogenic and mainly produced progesterone. The cancer cells that expressed progesterone receptors showed morphologic changes in response to hormonal stimulation.  相似文献   
994.
HADgels are newly developed photocrosslinked hyaluronate hydrogels. They are produced from an aqueous solution of a hyaluronan derivative (HAD) in which cinnamic acid is introduced into the carboxyl moiety of hyaluronan using 3-aminopropanol as a spacer. High-energy ultraviolet irradiation of the HAD solution induces photodimerization of cinnamic acid, resulting in the development of a macromolecular network of each hyaluronan to water-insoluble hydrogels. The biocompatibility and biodegradation of HADgels were evaluated by guinea pig intracutaneous injection testing for up to 28 days. By macroscopic and histological observations, HADgels showed good tissue compatibility and did not induce excess inflammation at the injection sites. Biodegradation of the HADgels clearly depended on the degree of crosslinking at the fixed weight concentrations of HAD (0.5% and 1.0%). In addition, serum analyses showed that the injected guinea pigs did not produce specific antibodies against HADgels. These results indicate that HADgels have preferable biocompatibility and can be used as a new class of injectable, absorbable biomaterial, especially for preventing postsurgical adhesion formations.  相似文献   
995.
The properties of the inward-rectifying Cl- conductance in rat choroid plexus epithelial cells were investigated to allow comparisons to be made with ClC-2. All experiments were performed using the whole-cell configuration of the patch-clamp method. The conductance was transiently activated using an electrode solution which contained 375 nM catalytic subunit of protein kinase A (PKA). PKA failed to activate the conductance, however, when cells were pre-incubated with phorbol esters, which activate protein kinase C [1 microM phorbol 12-myristate 13-acetate (PMA) and 1 microM phorbol 12,13-dibutyrate (PDBu)]. Sustained activation of the conductance by PKA was observed in Ca2+-free conditions (5 mM BAPTA in the electrode solution), or when 100 nM calphostin C, a PKC inhibitor, was added to the electrode solution. The inward-rectifying Cl- conductance in choroid plexus is therefore similar to ClC-2 in that it is inhibited by PKC. The inward-rectifying conductance was blocked when Cd2+ (30 and 300 microM) and Zn2+ (1, 30 and 300 microM) were added to the bath solution. ClC-2 channels are also blocked by Zn2+ and Cd2+. The magnitude of the inward conductance was dependent on the concentration of ATP in the electrode solution. The conductance was not observed when ATP in the electrode was replaced with non-hydrolysable ATP analogues [adenosine 5'-O-(3-thiotriphosphate) (ATP[gamma-S]) and 5'-adenylylimidodiphosphate (AMP-PNP)), but it was supported by UTP and GTP. These data contrast with those of previous studies in which ClC-2 channels were activated in the absence of ATP. In conclusion, the inward-rectifying Cl- channel in rat choroid plexus shares some properties with ClC-2 (inhibition by PKC and block by divalent cations), but differs in that it depends on intracellular ATP.  相似文献   
996.
Determinants of prognosis of acute transverse myelitis in children   总被引:2,自引:0,他引:2  
BACKGROUND: Acute transverse myelitis (ATM) is a severe disorder; recovery requires several months and often leaves neurologic residua. To determine what features of patients with acute transverse myelitis significantly influence prognosis, the authors reviewed reports of ATM in Japanese children published in the last 15 years (from 1987 to 2001). METHODS: The authors studied reports of 50 Japanese patients (17 boys, 26 girls, 7 children of unspecified sex; mean age +/- SD, 8.0 +/- 3.8 years). Acute-phase and demographic features including age, increased deep tendon reflexes, Babinski reflex, sex, preceding infection, decreased deep tendon reflexes, time course of peak neurologic impairment, treatment with prednisolone and/or high-dose methylprednisolone, and the day of illness when treatment was started were used as independent variables in a regression analysis. The dependent variable was long-term persistence of neurologic deficits. RESULTS: Younger patients and those without increased deep tendon reflexes or a Babinski reflex were more likely to have residual neurologic deficits such as paraplegia or tetraplegia, sensory loss and sphincter disturbance. No relationship was seen between prognosis and sex, preceding infections, decreased deep tendon reflexes, time course of peak neurologic impairment, treatment with prednisolone or high-dose methylprednisolone, or timing of treatment initiation. CONCLUSIONS: Age at onset and neurologic features were important for outcome prediction in ATM. Steroid therapy did not associate with better outcome.  相似文献   
997.
Long-term clinical results of 5 cases of urachal carcinoma   总被引:1,自引:0,他引:1  
Five cases of urachal carcinoma experienced in our hospital during the past 20 years are reported. Surgical resection is considered as the first treatment option of this disease, and other therapies to be less beneficial. Complete surgical extirpation and detection of recurrence in the early stage are considered to be important since local recurrence occurs frequently. We enforced the bladder preserving operation for 4 patients with urachal carcinoma except for 1 case with peritonitis carcinomatosa in the initial diagnosis, and multiple surgical treatment was performed again for 2 patients with recurrence. The bladder was preserved with no evidence of malignancy in three patients for 24, 19 and 5 years, respectively. In the initial management of urachal carcinoma, we believe that bladder-preserving surgery should be considered in selected cases though close follow-up is demanded. Herein, we also report the immunohistochemical study of paraffin-embedded specimens using anti-CEA, CA19-9, CA125 and p53 monoclonal antibodies. The positive reaction was observed in 100% (5/5) for CEA, 80% (4/5) for CA19-9, and 20% (1/5) for CA125. These results suggest that CEA may be a useful marker in the diagnosis of this neoplasm and early detection of its recurrence. Nuclear accumulation of p53 was observed in 80% (4/5), but it did not correlate with the disease progression.  相似文献   
998.
Clinical studies on renal pelvic and ureteral tumors   总被引:2,自引:0,他引:2  
Clinical studies were performed on 35 patients with renal pelvic and/or ureteral cancer treated at Kitano Hospital between 1988 and 1997. They consisted of 17 renal pelvic cancers, 17 ureteral cancers and 1 renal pelvic and ureteral cancer. Twenty-nine patients were males and six were females, and their age ranged from 41 to 82 years old (average: 62.2). Histologically, 34 were transitional cell carcinoma and 1 was adenocarcinoma. Pathological stage of the tumor was pTa in 34.3%, pT1 in 14.3%, pT2 in 11.4%, pT3 in 37.1%, and pT4 in 2.9%, and grade of the tumor G1 in 11.8%, G2 in 58.8% and G3 in 29.4%. Eighteen patients (51%) had or developed bladder cancer, which preceded the diagnosis of cancer of upper urinary tract in 2 cases, coexisted in 4 cases and developed subsequently in 12 cases. The overall cause-specific survival rate was 91.3% at 1 year, 83.8% at 3 years and 79.4% at 5 years. Tumor stage, grade, lymph node metastasis and vascular invasion had impact on survival.  相似文献   
999.
PURPOSE: ZD6126 is a novel vascular-targeting agent that selectively disrupts the tubulin cytoskeleton of endothelial cells. In the immature vessels characteristic of tumor vasculature, this leads to endothelial cell contraction, blood vessel congestion, and, consequently, tumor cell death. ZD6126 has been shown to delay tumor growth in a range of xenograft models. The antitumor effect of ZD6126 can be increased in combination with cisplatin or radiation therapy, although the precise mechanism of this enhancement has not been demonstrated. ZD6126 treatment has also been shown to inhibit lung metastasis, and the present study has explored the potential to increase the antimetastatic effect of ZD6126 by combining with cisplatin, and the underlining mechanism has been investigated. EXPERIMENTAL DESIGN: Human lung adenocarcinoma PC14PE6 cells were injected into the tail vein of nude mice. Five weeks after injection animals were treated with ZD6126 (200 mg/kg i.p.), cisplatin (6 mg/kg i.v.), or a combination of the two agents. The animals were sacrificed 24 hours later, and the extent of lung metastases and the presence of apoptotic cells were assessed. RESULTS: Histologic analysis revealed that the ZD6126/cisplatin combination resulted in a 2 to 4-fold increase in the total number of tumor-associated apoptotic cells compared with either treatment alone. ZD6126 alone induced apoptosis of tumor-associated endothelial cells in tumors, and the extent of apoptosis was increased 2-fold in combination with cisplatin. The lung weight was significantly reduced, and the number of metastatic nodules significantly was lower in the combined treatment group than in the control group. CONCLUSIONS: These data suggest that the antimetastatic effect of the vascular-targeting agent ZD6126 can be increased by use in combination with cisplatin, which increases the incidence of endothelial cell apoptosis.  相似文献   
1000.
PURPOSE: Oxytocin (OT) was reported to inhibit the proliferation of various neoplastic tissues and cells, however, the regulation system remains unclear. This study examined the role of OT and its regulatory ability in endometrial adenocarcinoma. EXPERIMENTAL DESIGN: To investigate the possible function of placental leucine aminopeptidase (P-LAP) in endometrial adenocarcinoma, we transfected P-LAP cDNA into A-MEC cells, showing the lowest enzyme activity of P-LAP. Also we examined P-LAP protein expression in human endometrial adenocarcinoma. RESULTS: We demonstrated the presence of P-LAP, which is identical to cystine aminopeptidase as oxytocinase, in human endometrial adenocarcinoma tissues and found that the expression of P-LAP increase with advances in the grade. Exposure of endometrial adenocarcinoma cell lines to OT caused dose- and time-dependent inhibition of growth. Treatment with 10(-7) M OT for 72 h reduced cell growth by 62, 25, and 30% in A-MEC, HEC1A, and Ishikawa cells, respectively. P-LAP-transfectant cells not only partially recovered from OT-induced growth inhibition but also showed a higher growth rate than parental cells under condition without OT. An OT receptor antagonist and a protein kinase A inhibitor blocked OT-induced growth inhibition in A-MEC and A-MEC-pc cells but not in A-MEC-LAP cells. CONCLUSIONS: These findings suggested that P-LAP might be functionally positive on carcinoma cell growth by degrading suppressive peptides such as OT.  相似文献   
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