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81.
To investigate immune effects of interferon (IFN) therapy in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B, serum immunoglobulin concentrations and peripheral lymphocyte subpopulations were sequentially studied before, during, and after therapy in nine patients who were treated with recombinant human -IFN in doses ranging from 3 to 10 million units per day for 28 days. Serum immunoglobulin A levels decreased significantly, from 414±23 mg/dl (mean ± SE) to 379±28 mg/dl (P<0.05), after the first week of therapy and to a bottom value of 323±20 mg/dl (P<0.001) at the fourth week. Immunoglobulin G levels decreased significantly, from 2603±175 to 2328±169 mg/dl (P<0.005), after the first week of therapy and to a bottom value of 2005±199 mg/dl (P<0.001) at the fourth week. Immunoglobulin M levels were also reduced significantly after 3 weeks of therapy (from 229±23 to 188±15 mg/dl;P<0.01). These reductions in immunoglobulins A, G, and M returned to pretreatment levels by 4 months after the end of the therapy. In lymphocyte subpopulations, significant depressions were found in CD3-, CD4-, CD8-, and B1-positive cells in peripheral blood after the first week of therapy (CD3, from 1700±114 to 1234±114/mm3,P<0.005; CD4, from 1036±88 to 780±64/mm3,P<0.005; CD8, from 620±57 to 426±60/mm3,P<0.05; and B1, from 519±84 to 276±48/mm3,P<0.01) followed during therapy, while Leul la-positive cells did not change significantly. During the 6-month follow-up period, three patients had a sustained clinical remission in which HBeAg disappeared from serum. Disappearance of HBeAg was unassociated with initial levels or percentage changes of serum immunoglobulins and peripheral lymphocytes expressing each of the test markers in these patients. These findings suggest that immune effects of IFN therapy are independent from its antiviral effects.  相似文献   
82.
A 27-year-old female patient with alcoholic cirrhosis was reported. She was admitted to the hospital because of jaundice and ascites after heavy drinking. She had a history of drinking Japanese Sake in quantities of more than 5 go/day (900 ml/day) for 7 years. On admission, she was icteric, and had both hepatosplenomegaly and ascites. Laboratory data showed an elevation of serum transaminase and bilirubin, and a decrease in the albumin and prothrombin values. A biopsy specimen of the liver showed pericellular fibrosis, fatty change, Mallory bodies and regenerative nodules, and revealed findings compatible with alcoholic cirrhosis. A 99mTc-N-pyridoxyl-5-methyltryptophan scintigram showed hepatomegaly. On the 99mTc-phytate scintigram, the uptake of radioisotope to the liver was markedly decreased with the increased uptake to the spleen and bone marrow. Even 6 months after the onset, poor visualization of the hepatic image on 99mTc-phytate scintigram continued. This is the first report of alcoholic cirrhosis demonstrating a long-term poor visualization of the hepatic image on 99mTc-phytate scintigraphy.  相似文献   
83.
84.
Tsuji H 《Biomaterials》2003,24(4):537-547
Well-homocrystallized enantiomeric blend and nonblended films were prepared from poly(L-lactide), i.e., poly(L-lactic acid) (PLLA) and poly(D-lactide), i.e., poly(D-lactic acid) (PDLA) by crystallization from the melt. The effects of enantiomeric blending on the in vitro autocatalytic hydrolysis of the homo-crystallized polylactide, i.e., poly(lactic acid) (PLA) films were investigated in phosphate-buffered solution (pH 7.4) at 37 degrees C for up to 24 months. In the period of 0-12 months, the effects of enantiomeric polymer blending on the autocatalytic hydrolysis were very small. This finding reflects that in the PLLA/PDLA blend film separate homo-crystallization of PLLA and PDLA into the respective crystallites reduced the peculiar strong interaction between PLLA and PDLA chains in the amorphous region between the homo-crystalline regions. In the period of 12-24 months, enantiomeric polymer blending significantly retarded the autocatalytic hydrolysis of the PLLA/PDLA blend film compared with that of the nonblended PLLA and PDLA films. This is attributable to the increased chain mobility and the reduced entanglement effects due to the chain cleavage to a great extent, resulting in the enhanced interaction between PLLA and PDLA chains. It was also revealed that the hydrolyzabilities of the PLA films can be widely varied by enantiomeric polymer blending, crystalline species and their amounts, and molecular weight.  相似文献   
85.
Hamsters are frequently studied as a model of cardiomyopathy, but the electrophysiological properties of a hamster heart are not well defined. We examined rate-dependent changes in action potentials and underlying ionic mechanisms in isolated ventricular myocytes from hamster hearts using the whole-cell configuration of the patch clamp technique. At 0.1 Hz stimulation, the mean action potential duration at 90% (APD90) and 20% (APD20) repolarization were 63+/-7 ms and 9+/-1 ms, respectively ( n=17). With increasing frequency of stimulation, APD progressively prolonged to 119+/-16 ms (APD90) and 36+/-7 ms (APD20) at 6.0 Hz. A further increase in the rate of stimulation to 8.0 Hz did not change APD significantly. Application of 4 mM 4-aminopyridine (4-AP) lengthened APD markedly and completely prevented the rate-dependent prolongation. Cd2+ (0.2 mM) shortened APD and generally attenuated the rate-dependent lengthening of APD up to 5.0 Hz, but unaffected the lengthening of APD with the further increase in the rate. At plateau voltages, there were two time-dependent currents, Ito1 and I(Ca,L). Recovery from inactivation for Ito1 had two components: t(slow)=980+/-129 ms accounting for 58% of the total fraction, and t(fast)=39+/-13 ms ( n=7). Recovery from inactivation for I(Ca,L) was rapid with t=20+/-4 ms ( n=6). Results suggest that the slow recovery from inactivation in Ito1 is the main reason for the rate-dependent prolongation of APD in hamster ventricular myocytes.  相似文献   
86.
It is generally accepted that levels of serum whole complement activity (CH50) reflect the activities of complement (C) components of the classical C pathway (CP), since CH50 is assayed by use of sensitized sheep erythrocytes (EA). However, the alternative C pathway (AP) is considered to be also activated simultaneously in the process of activation of serum CP by EA. Thus, serum CH50 levels may possibly reflect not only CP but also AP activation in CH50 assay. We studied on the influence of AP activation during CH50 assay on CH50 levels, by comparison of CH50 levels in serum samples before and after treatment of factor D depletion. Polystyrene beads carrying polyanion, poly (2-acrylamide 2-methylpropane sulfonate) (PAMPS-beads), on the surface were prepared and used for preparation for factor D-depleted serum. After treatment of pooled normal human serum (NHS) with PAMPS-beads (2.5 mg/ml of serum), serum ACH50 level decreased to be undetectable, indicating that AP activation is prohibited in PAMPS-beads-treated serum. When isolated factor D was added to this PAMPS-beads-treated serum, ACH50 level recovered to that of before treatment. Immunoblot analysis revealed that factor D band observed in NHS disappeared completely after PAMPS-beads treatment. From these results, it is clear that factor-D deficient serum is prepared by PAMPS-beads treatment. Besides, since serum CH50 level was not decreased by PAMPS-beads treatment, it may be concluded that CH50 level is not affected by AP activation during CH50 assay.  相似文献   
87.
88.
We investigate, by the immunogold method, the localization of keratan sulfate (KS) proteoglycan in rat calvaria in order to clarify the detailed process of intramembranous ossification. KS was localized in bone nodules corresponding to calcified nodules, close to the saggital suture of calvaria. The immunoreactivity decreased in fully calcified regions distant from the suture. Electron microscopic observation revealed that KS was distributed in and around matrix vesicles, among collagen fibrils at the initial crystal deposition stage, and then concentrated in bone nodules. According to the progress of mineralization, KS tended to be localized in the peripheral region of the nodules. In addition, these nodules came in contact with collagen fibrils which also showed KS-positive reactivity. In cell organelles of osteoblasts, KS was detected in the Golgi apparatus. These findings suggest that osteoblasts in intramembranous ossification sites actively synthesize KS. KS in the calcified nodules, as well as other glycosaminoglycans in osteoid, may play an important role in additional and/or collagenous calcification by trapping calcium ions through its negative charge.  相似文献   
89.
he present study examined strain differences in the light-dark preference among four strains of rats. The test was done in the home-cage situation under 12L:12D cycles. Data from four strains were compared: BN/Kyo, BDIX/Nem, Wistar/Nu, and F344/NSlc. These strains differed in the light-dark preference measured by the ratio of the time spent in the field area of the home cage during the light period. BN/Kyo and BDIX/Nem spent the most time (approx. 23%) in the field during the light period, while F344/NSlc spent the least time (approx. 5%). Wistar/Nu fell between the two (approx. 12%).This study was conducted as partial fulfillment for the master's degree, submitted to Nagoya University by the first author. It was presented at the 47th Annual Conference of the Japanese Society of Animal Psychology.  相似文献   
90.
This study was undertaken to determine whether the specific Th1- or Th2-cell response to varicella-zoster virus was induced predominantly by a mucosal adjuvant, cholera toxin, in mice. A commercially available live varicella vaccine (Oka strain) and cholera toxin or its B subunit were administered simultaneously via the nasal route. Delayed-type hypersensitivity to the Oka vaccine was induced, but the systemic neutralizing antibody response was low. The delayed-type hypersensitivity evoked after a single administration was relatively higher than that on administration three times. When spleen cells from mice immunized once with the vaccine and cholera toxin or its B subunit were restimulated with the live vaccine in vitro, there was greater thymidine uptake and production of interleukin- 2 (IL-2) than controls, but only a low level of IL-4 production. The production of IL-2 induced by the B subunit of cholera toxin was less than that by cholera toxin and a mutant of Escherichia coli enterotoxin on co-immunization with the vaccine in mice. Cholera toxin and its B subunit have been reported to induce predominantly a specific Th2-type T-cell response to various antigens. However, the Oka vaccine is an antigen that polarizes the activation of specific Th1/Th2-type T cells by cholera toxin or its B subunit to the Th1-type side. Cholera toxin and its B subunit are thus useful mucosal adjuvants for inducing cellular immunity to the Oka vaccine similar to Escherichia coli enterotoxin.  相似文献   
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