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61.
62.
Mixed connective tissue disease with fatal pulmonary hypertension and a review of literature 总被引:2,自引:0,他引:2
Norifumi Ueda Keiko Mimura Hitoshi Maeda Taketoshi Sugiyama Tetsuji Kado Katsuya Kobayashi Hisashi Fukuzaki 《Virchows Archiv : an international journal of pathology》1984,404(4):335-340
Summary The paper presents an autopsy case of mixed connective tissue disease (MCTD) with pulmonary hypertension (PH) and a review of literature. A 33-year-old woman with Raynaud's phenomenon and dyspnea of one year duration was diagnosed as having MCTD on the basis of a higher titer (1:163,840) of serum antibodies to the ribonucleoprotein (RNP). Cardiac catheterization showed complicating PH, confirmed an autopsy by the findings of concentric intimal cellular proliferation and typical plexiform lesions in the small arteries and arterioles of the lung, suggesting primary PH. Fatal PH with MCTD has been reported only 6 cases in literature including our case. All were young females, with histopathological findings consistent with plexogenic pulmonary arteriopathy in 5 cases and with recurrent pulmonary thromboembolism in the other. The aetiology of PH is still unknown, but it may be due to vasoconstriction evoked by the hyper-reactivity of the vessels. 相似文献
63.
Hyperalgesia to mechanical stimulation and heat is commonly observed in inflamed conditions. Although sensitization to heat is well documented and its mechanism has also been well studied, it remains unclear whether and how nociceptors are sensitized to mechanical stimulation. Therefore we conducted in vitro investigation of which inflammatory mediators (bradykinin, histamine, prostaglandin E2, and protons) sensitize nociceptors to suprathreshold mechanical stimulation and at what concentrations. In addition, we studied the effects of possible second messengers for these mediators downstream of the receptors and also the effects of mild burn. Single polymodal receptor activities were recorded in canine testis-spermatic nerve preparations excised from deeply anesthetized dogs. Mechanical stimulation was applied to the identified receptive field for 10 s with a servo-controlled mechanical stimulator. Bradykinin at 0.001 microM induced neither excitation nor facilitation of the mechanical response; however, it facilitated the mechanical response at 0.01 microM and higher, levels at which significant excitation was also induced by bradykinin alone. Histamine excited the nociceptor and sensitized it to mechanical stimulation at 10 microM and higher. PG E(2) also sensitized the mechanical response, but starting at 1 microM, without inducing excitation by itself. The effects of two possible intracellular messengers for these mediators were studied using forskolin (10 microM), which increases intracellular cAMP, and a protein-kinase-C-stimulating phorbol ester, phorbol 12,13-dibutyrate (0.1 microM). Both substances reversibly facilitated the mechanical response of testicular polymodal receptors. In contrast, low-pH solution (pH: 6.6-4.5) seldom induced excitation and failed to facilitate the mechanical response. After 55 degrees C, 30-s heat stimulation, testicular polymodal receptors were sensitized to mechanical stimulation. These results demonstrated that inflammatory mediators and burn sensitized nociceptor responses to mechanical stimulation and provide support for the idea that peripheral nociceptor sensitization is a mechanism involved in hyperalgesia to mechanical stimulation in inflamed tissues. 相似文献
64.
Kazuki Hayasaka Yui Watanabe Takashi Hirama Hisashi Oishi Masafumi Noda Hiroaki Toyama Yutaka Ejima Yoshikatsu Saiki Yoshinori Okada 《Transplantation proceedings》2021,53(4):1385-1387
Although single-lung transplant on the side with better lung function is challenging in patients with significantly asymmetrical lung function between the right and left sides, it sometimes can be a realistic option because of the recipient's condition and from the viewpoint of organ sharing. We report our experience with a successful case of single-lung transplant on the side with a pulmonary perfusion ratio of 89%. The transplant was performed with the patient under central venoarterial extracorporeal membrane oxygenation through a clamshell incision, and the patient had an acceptable short- and long-term outcome with a remarkable improvement of lung function. 相似文献
65.
66.
Shuzo Oshita Yoshiki Fujiwara Hisashi Tamura Takefumi Sakabe Hiroshi Takeshita 《Journal canadien d'anesthésie》1994,41(6):534-541
To gain a better understanding of the direct actions of halothane on myocardial function in ischaemia, we studied the effects
of increasing extracellular potassium concentration and decreasing extracellular pH (acidosis), alone or in combination with
halothane, on the contractile force and resting tension in isolated atria. Guinea pig left atria were superfused with Tyrode’s
solution and stimulated at 1 Hz. Isometric contractile force and resting tension were measured using a force displacement
transducer. Perfusate potassium concentrations were increased from 5.4 mmol · L−1 to either 8.1 mmol · L−1 or 10.8 mmol · L−1 by adding KCl to the standard Tyrode’s solution, and its pH was decreased from 7.4 to either 7.0 or 6.5 by decreasing bicarbonate.
In standard Tyrode’s solution (potassium 5.4 mmol · L−1, pH 7.4), halothane 0.5–2% reduced contractile force in a dose-dependent manner (P < 0.05); the effective concentration of
halothane for 50% inhibition of contractile force (IC50) was 1.3%. Both increasing extracellular potassium and decreasing extracellular pH decreased the contractile force in a potassium-or
pH-dependent fashion. The negative inotropism of halothane (1%) was not altered by increasing potassium concentrations, whereas
1% halothane caused a greater decrease in contractile force at pH 6.5 than at pH 7.4. Halothane (1%) enhanced the acidosis
(pH 6.5)-induced increases in resting tension. Arrhythmias were produced in one of eight preparations during acidosis, while
four of eight preparations demonstrated arrhythmias during acidosis in the presence of halothane. These data suggest that
acidosis and halothane may have a synergistic interaction on the contractile force and resting tension of the atria. The increase
in resting tension observed during acidosis/ halothane conditions suggests than an increase in cytosolic calcium is associated
with these synergistic interactions between acidosis and halothane.
Pour mieux comprendre l’action direct de l’halothane sur la fonction myocardique pendant l’ischémie, nous avons étudié les
effets de l’augmentation du potassium extracellulaire et de la diminution du pH extracellulaire (acidose), seuls ou en association
avec l’halothane, sur la force contractile et la tension de repos d’oreillettes isolées. Des oreillettes gauches de cobaye
furent perfusées avec une solution de Tyrode et stimulées à 1 Hz. La force contractile isométrique et la tension de repos
ont été mesurées avec un transducteur de force de déplacement. Les concentrations de potassium perfusées ont été augmentées
de 5,4 mmol · L−1 à 8,1 mmol · L−1 ou à 10,8 mmol · L−1 par l’ajout de KCl à la solution standard de Tyrode, et son pH abaissé de 7,4 à 7,0 ou 6,5 par baisse des bicarbonates. Avec
la solution standard de Tyrode (potassium 5,4 mmol · L−1, pH 7,4), l’halothane (0.5–2%) diminue la force contractile proportionnellement à la dose (P < 0,05); la concentration efficace
d’halothane requise pour produire une inhibition de 50% de la force contractile (IC5O) a été de 1,3%. L’augmentation du potassium extracellulaire et la diminution du pH extracellulaire réduisent toutes les deux
la force contractile proportionnellement au potassium ou au pH. L’inotropisme négatif de l’halothane (1%) n’est pas modifié
par l’augmentation de la concentration de potassium alors que l’halothane produit une diminution plus importante de la force
contractile à un pH de 6,5 que de 7,4. L’halothane (1%) exagère l’augmentation de la tension de repos induite par l’acidose
(pH 6,5). Des arrythmies sont apparues sur une des huit préparations pendant l’acidose en présence d’halothane. Ces données
suggèrent que l’acidose et l’halothane pourraient avoir une activité synergique sur le force contractile et la tension de
repos des oreillettes. L’augmentation de la tension de repos observée pendant l’acidose combinée à l’halothane suggère l’association
d’une augmentation du calcium cytosolique avec des interactions synergiques entre l’acidose et l’halothane. 相似文献
67.
Hisashi Kuribara 《Psychopharmacology》1994,116(2):125-129
Methamphetamine (MAP: 1 and 2 mg/kg SC) and caffeine (CAF: 1, 3, 10 and 30 mg/kg SC) dose-dependently increased ambulation in mice. Repeated administration (5 times at 3 to 4-day intervals) of MAP, but not CAF, induced sensitization to its effect. Furthermore, the mice repeatedly receiving CAF showed no significant change in the sensitivity to MAP. Combined administration of MAP with CAF increased the effect. In the combinations of MAP (1 mg/kg) with CAF (3, 10 and 30 mg/kg), and MAP (2 mg/kg) with CAF (1 and 3 mg/kg), the effect was enhanced by the repeated administration. However, MAP sensitization was not modified by the combination with CAF in the repeated administration schedule, except in the combination of MAP (1 mg/kg) with CAF (30 mg/kg). The ambulation-increasing effects of MAP (1 mg/kg), CAF (10 mg/kg) and combination of MAP with CAF were almost equivalently inhibited by SCH 23390 (0.01 and 0.1 mg/kg SC) and YM-09151-2 (0.01 and 0.1 mg/kg SC). However, the inhibitory effects of apomorphine (0.05 mg/kg SC) andN
6-(L-phenylisopropyl)-adenosine (0.1 and 0.2 mg/kg SC) were stronger for CAF than for MAP and the combination, and those of -methyl-p-tyrosine (200 mg/kg IP, 4 h before) and reserpine (1 mg/kg SC, 4 h before) were stronger for MAP and CAF alone than for the combination. The present results suggest that, although the combination of MAP and CAF enhances the ambulation-increasing effect through an interaction at dopaminergic system, CAF may not significantly modify the induction of MAP sensitization in mice. 相似文献
68.
Yoshikawa H Myoui A Ochi T Araki N Ueda T Kudawara I Nakanishi K Tanaka H Nakamura H 《Seminars in musculoskeletal radiology》1999,3(2):183-190
The incidence, distribution, time of appearance, and radiologic findings of bone metastases from soft tissue sarcomas, exclusive of lymphomas, were evaluated in 320 patients with soft tissue sarcomas. Thirty patients (9.4%) had evidence of 58 bone metastases. Five of 30 patients presented with metastases, and 25 of 30 patients developed metastases up to 66 months after presentation with a mean time interval of 21.3 months. The incidence of skeletal metastases differed among histologic subtypes of sarcomas; alveolar soft part sarcoma (5 of 8), dedifferentiated liposarcoma (2 of 4), angiosarcoma (2 of 4), and rhabdomyosarcoma (5 of 16) tended to show a higher incidence of bone metastases. The sarcomas metastasized to the regional bones close to the primary tumor in 16 (53%) of 30 patients and to the axial bones in 18 (60%). On conventional radiographs, the osseous metastases demonstrated predominantly osteolytic changes, and evidence of pathological fracture was observed in 31% of 58 metastases. 相似文献
69.
Ichinose Y Okino T Yamasaki S Moriguchi Y Sugie T Li L Kanaoka S Kan N Watanabe Y Imamura M 《Surgery today》1999,29(4):338-343
To evaluate the effect of interferon-γ-genetransduced cells, DS mice were inoculated into their footpads with syngeneic mammary
adenocarcinoma SC42 admixed with interferon-γ producing mammary adenocarcinoma SC115Kγ, which had been established by an interferon-γ-gene
transduction in another syngeneic mammary adenocarcinoma SC115 using retroviral vectors. These mice rejected both tumor cells
and developed resistance to subsequent challenges with either SC115 or SC42 cells inoculated into their opposite posterior
footpads. These results thus indicate that systemic immunological memory to each of the independent tumor cell lines developed
in these mice. Although the SC42 cells admixed with irradiated SC115Kγ cells were rejected by these mice, the SC42 cells admixed
with irradiated SC115neoR, in which the neo-gene had been transduced, were observed to proliferate. Tumor rejection was reversed
by an in vivo administration of anti-interferon-γ antibody, thus suggesting that locally produced interferon-γ plays an important
role in tumor elimination and immunological memory induction. In conclusion, interferon-γ-gene-transduced tumor cells are
therefore considered to have a therapeutic potential for other types of malignant tumor cell lines. 相似文献
70.
Tracheomalacia (TM) is well known as a complication associated with esophageal atresia (EA) and tracheoesophageal fistula
(TEF); however, the occurrence of TM requiring surgical treatment in a patient having EA without a tracheoesophageal fistula
has never been reported. We describe herein a rare case of TM associated with EA without TEF. Respiratory distress was caused
by compression of the trachea by a severely dilated upper esophageal pouch with weakness of the tracheal wall. Aortopexy was
performed, and an excellent postoperative result was achieved. 相似文献