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Background: Ketamine potentiates intravenous or epidural morphine analgesia. The authors hypothesized that very-low-dose ketamine infusion reduces acute and long-term postthoracotomy pain.

Methods: Forty-nine patients scheduled to undergo open thoracotomy were randomly assigned to receive one of two anesthesia regimens: continuous epidural infusion of ropivacaine and morphine, along with intravenous infusion of ketamine (0.05 mg [middle dot] kg-1 [middle dot] h-1 [approximately 3 mg/h], ketamine group, n = 24) or placebo (saline, control group, n = 25). Epidural analgesia was continued for 2 days after surgery, and infusion of ketamine or placebo was continued for 3 days. Pain was assessed at 6, 12, 24, and 48 h after surgery. Patients were asked about their pain, abnormal sensation on the wound, and inconvenience in daily life at 7 days and 1, 3, and 6 months after surgery.

Results: The visual analog scale scores for pain at rest and on coughing 24 and 48 h after thoracotomy were lower in the ketamine group than in the control group (pain at rest, 9 +/- 11 vs. 25 +/- 20 and 9 +/- 11 vs. 18 +/- 13; pain on coughing, 26 +/- 16 vs. 50 +/- 17 and 30 +/- 18 vs. 43 +/- 18, mean +/- SD; P = 0.002 and P = 0.01, P < 0.0001 and P = 0.02, respectively). The numerical rating scale scores for baseline pain 1 and 3 months after thoracotomy were significantly lower in the ketamine group (0.5 [0-4] vs. 2 [0-5] and 0 [0-5] vs. 1.5 [0-6], median [range], respectively; P = 0.02). Three months after surgery, a higher number of control patients were taking pain medication (2 vs. 9; P = 0.03).  相似文献   

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Summary Novel derivatives of K-252a, (8R*,9S*,11S*)-(–)-9-hydroxy-9-methoxycarbonyl-8-methyl-2,3,9,10-tetrahydro-8, 11-epoxy-1H,8H,11H-2,7b,11a-triazadibenzo [a,g]-cycloocta[cde]trinden-1-one, an inhibitor of protein kinases and calmodulin-dependent phosphodiesterase, were synthesized and evaluated for their antitumor activity in vitro and in vivo. Of ten derivatives tested, four were active against the P388 murine leukemia i. p.-i. p. system, although K-252a was inactive. Among these derivatives, KT6124 was selected for further biological evaluation studies because its efficacy was the highest. KT6124 was also active against sarcoma 180 and B16 melanoma. It exerted a relatively broad spectrum of antiproliferative activity against 20 human tumor cell lines in vitro. To determine the mechanism(s) of action underlying the antitumor activity of KT6124, we tested the drug for inhibition of protein kinases, including Ca2+-and phospholipid-dependent protein kinase (PKC), in intact A431 human epidermoid carcinoma cells in comparison with the PKC-inhibitory activity of K-252a. KT6124 did not antagonize the action of phorbol 12-myristate 13-acetate (PMA) in A431 cells, whereas K-252a did, suggesting that KT6124 may not act on protein kinases in the cells. The interaction of KT6124 with DNA in living cells was examined by the alkaline elution method. KT6124 apparantly exhibited DNA scission both dose-and time-dependently in the target cells. The DNA breakage was dependent on proteinase K treatment, suggesting its possible interaction with DNA-related enzyme(s). These results indicate that KT6124 exerts antitumor activity by acting on DNA or on DNA-related enzyme(s) in tumor cells rather than via the inhibition of protein kinases.  相似文献   
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To prepare single smooth muscle cells from the taenia coli of guinea pig, the application of papain to the enzymatic solution was examined under two conditions: 1) the isolation in a modified Tyrode solution (containing 0.18 mM Ca2+: 0.18 mM Ca2+-Tyrode solution) and 2) the isolation in a high-K+ Tyrode solution (Na+ was replaced by K+, and Ca2+ was not added: high-K+ Tyrode solution). The presence of papain during collagenase digestion reduced contamination of broken cells and cell debris. In the case of the high-K+ Tyrode solution, papain increased the yield of single cells significantly. The cells were contracted in a dose-dependent manner by Ca2+ in the high-K+ Tyrode solution and by carbachol in 0.18 mM Ca2+-Tyrode solution; furthermore, the contractions were antagonized by verapamil and atropine, respectively. Treatment with papain did not affect cell sensitivity to the stimulants. Therefore, our results suggest that the addition of papain is useful for the isolation of single cells to investigate the physiological and pharmacological characteristics of smooth muscle.  相似文献   
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PURPOSE: To determine the effect of an interposition nerve graft on sexual function after radical prostatectomy. METHODS: This study includes 64 patients, without hormonal therapy, who underwent a radical prostatectomy and intraoperative electrophysiological confirmation of cavernous nerve preservation. Twelve patients underwent a unilateral interposition sural nerve graft (UNG) for the resected neurovascular bundle. Twenty-one and 31 patients underwent bilateral nerve-sparing (BNS) and unilateral nerve-sparing (UNS) surgery without a nerve graft, respectively. As the age of patients was significantly younger in the UNG group than in the other groups, age-matched analysis also was conducted. Sexual function, evaluated by a self-administered questionnaire using the University of California Los Angeles-Prostate Cancer Index, was compared statistically among the three groups. RESULTS: In the age-matched analysis, the postoperative sexual function (SXF) score of the UNG group showed an intermediate level of recovery between those of the BNS and UNS groups at 12 months and reached the same level as the score at 12 months of the BNS group at 18 months postoperatively. The difference in the SXF score between the UNG and UNS groups began to appear after 6 months postoperatively and increased steadily with time. However, the background factors, such as the baseline SXF score, the usage rate of phosphodiesterase 5 inhibitors, and the rate of comorbidities were different between the UNG and UNS groups. CONCLUSIONS: The difference of the SXF score between the UNG and UNS groups increased with time after 6 months postoperatively. However, it might be difficult at present to attribute a better recovery of the SXF score to the nerve graft because of the difference in the background factors between the groups.  相似文献   
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OBJECTIVE: Standard chemotherapy shows relatively low long-term survival in patients with poor-risk testicular germ cell tumor (GCT). First-line high-dose chemotherapy (HD-CT) may improve the result. High-dose carboplatin, etoposide, ifosfamide chemotherapy followed by autologous peripheral blood stem cell transplantation (PBSCT) was investigated as first-line chemotherapy in patients with advanced testicular GCT. METHODS: Fifty-five previously untreated testicular GCT patients with Indiana 'advanced disease' criteria received three cycles of bleomycin, etoposide and cisplatin (BEP) followed by one cycle of HD-CT plus PBSCT, if elevated serum tumor markers were observed after three cycles of the BEP regimen. RESULTS: Thirty patients were treated with BEP alone, because the tumor marker(s) declined to normal range. Twenty-five patients received BEP and HD-CT. One patient died of rhabdomyolysis due to HD-CT. Three and six (13% and 25%) out of 24 patients treated with BEP and HD-CT achieved marker-negative and marker-positive partial responses, respectively. The other patients achieved no change. Fifteen (63%) are alive and 14 (58%) are free of disease at a median follow-up time of 54 months. Severe toxicity included treatment-related death (4%). CONCLUSIONS: HD-CT with peripheral stem cell support can be successfully applied in a multicenter setting. HD-CT demonstrated modest anticancer activity for Japanese patients with advanced testicular GCT and was well tolerated. This regimen might be examined for further investigation in randomized trials in first-line chemotherapy for patients with poor-risk testicular GCT.  相似文献   
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Abstract: Light microscopic observations on the superficial pineal gland of Wistar-King rats were made to examine whether or not pineal volume and pinealocyte size, expressed as nuclear density, at daytime or nighttime are affected by long-term exposure to 50 Hz rotating magnetic field (MF) at 5.0 μT. Determinations of pineal volume and pinealocyte size were repeated twice (April and October) during the year. Size of pinealocytes in MF-exposed and sham-exposed rats exhibited, in addition to the difference between peripheral and central regions, regional differences in a proximodistal direction; pinealocytes in the distal and middle-peripheral regions were usually larger than those in the proximal and middle-central regions at daytime or nighttime. In October, distal and proximal pinealocytes showed significant day-night changes in size in sham-exposed rats, but not in MF-exposed animals. The situations in the two groups were almost reversed in April. Significant day-night differences were scarcely found in pinealocyte size in the middle region in the two groups. Throughout the study, pineal volume and pinealocyte size in each region were generally the same between MF-exposed and sham-exposed rats at daytime or nighttime. The results suggest that pinealocytes in the distal and proximal regions, but not those in the middle region, are affected by MF-exposure; day-night differences in sizes of distal and proximal pinealocytes appear in April and disappear in October under the influence of MF. MF may exert an effect on mechanisms controlling day-night rhythms of pinealocyte size in the rat.  相似文献   
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