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81.
Proteolysis and invasiveness of brain tumors: Role of urokinase-type plasminogen activator receptor 总被引:2,自引:0,他引:2
Sanjeeva Mohanam Raymond E. Sawaya Masaaki Yamamoto Janet M. Bruner Garth L. Nicholson Jasti S. Rao 《Journal of neuro-oncology》1994,22(2):153-160
Summary The cellular receptor for urokinase-type plasminogen activator (uPAR) in glioblastoma cell lines has been identified and found to be similar to the uPAR expressed by other tumor cell lines. Increased levels of uPAR have been found in primary malignant brain tumor tissues, especially highly malignant glioblastoma, and, to a lesser degree, in malignant astrocytomas, suggesting that this receptor might be involved in efficient activation of pro-uPA and confinement of uPA activity on the cell surface of invading brain tumors. The cell surface uPARs in gliomas could constitute an optimum environment for the generation and activity of plasmin, which is known to play a crucial role in the dissolution of the extracellular matrix during tumor cell invasion.In situ hybridization studies have shown that uPAR mRNA is expressed abundantly in tumor cells and is consistently present at the invasive edges of malignant gliomas. These results imply that uPAR is involved in plasmincatalyzed proteolysis during glioma invasion and that interference with the uPAuPAR interactions could constitute a novel approach for developing therapeutic strategies to counteract invasion of brain tumors. 相似文献
82.
Nishio M Xu L Sasaki M Haga S Okumoto M Mori N Sarkar NH Acha-Orbea H Enami J Imai S 《Breast cancer (Tokyo, Japan)》1994,1(2):89-94
Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid. 相似文献
83.
The delayed neurotoxic organophosphate, diisopropylfluorophosphate (DFP) binds with high affinity to membrane-bound proteins
from chicken nerve tissues. The autoradiographic distribution of [3H]DFP binding sites in spinal cord sections of chicken showed higher concentrations of binding sites in gray matter than in
white matter. In the cervical region, fairly high densities of [3H]DFP binding sites were found in laminae X and to a lesser extent, in the ventral horn gray matter. To identify the membrane-associated
DFP-binding proteins, detergent-solubilized membranes were labeled widi 5-10nM [3H]DFP (10pmol/mg protein) for 70 min at 37°C. Gel-exclusion chromatography of the [3H]DFP-radiolabeled membranes indicated at least two major radioactive proteins with apparent molecular weights of 150-670
kDa and 40-129 kDa. Although we could not identify the high affinity DFP binding proteins, the autoradiographic experiments
clearly demonstrated that the DFP binding proteins localized on gray matter of chicken spinal cord. 相似文献
84.
Karube Y Katsuno K Ito S Matsunaga K Takata J Kuroki M Murakami M Matsuoka Y 《Annals of nuclear medicine》1999,13(6):407-413
The method for subtracting the initial image from the localization image was evaluated for radioimmunoscintigraphy of tumors with technetium-99m (Tc-99m) labeled antibodies. Monoclonal antibodies were parental mouse and mouse-human chimeric antibodies to carcinoembryonic antigen (CEA), designated F11-39 and ChF11-39, respectively, both of which have been found to discriminate CEA in tumor tissues from the CEA-related antigens. After reduction of the intrinsic disulfide bonds, these antibodies were labeled with Tc-99m. In vivo studies were performed on athymic nude mice bearing the human CEA-producing gastric carcinoma xenografts. Though biodistribution results showed selective and progressive accumulation of Tc-99m labeled antibodies at the tumor site, high radioactivity in blood was inappropriate for scintigraphic visualization of the tumors within a few hours. We examined the subtraction of the initial Tc-99m image from the Tc-99m localization image after a few hours. Subtracted images of the same count reflected the in vivo behavior of the Tc-99m radioactivity. The subtracted scintigrams revealed excellent tumor images with no significant extrarenal background. Visualization of the tumor site was dependent on antigen-specific binding and nonspecific exudation. These results demonstrate that a method of subtraction of the initial image may serve as a potentially useful diagnostic method for an abnormal site for agents with a low pharmacokinetic value. 相似文献
85.
J Fukui F Nukui K Kontani M Nagata J Kurokawa M Katsuta T Sugimura S Okamoto H Komatsu 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1999,90(9):769-778
PURPOSE: Psychogenic lower urinary tract dysfunction (PLUTD) is composed of two syndromes; psychogenic frequency-urgency syndrome (PFUS) and psychogenic urinary retention (PUR). We evaluated the patho-physiology of PFUS and PUR, and explored the different pathogenesis in these syndromes. MATERIAL AND METHODS: Forty five patients with PLUTD, consisting of 23 patients with PFUS and 22 patients with PUR were investigated by using the psychological tests: CMI (Cornell Medical Index) and TEG (Todai's Egogram), a quantitative perspiration test in 45 females (23 patients with PFUS and 22 patients with PUR), and simultaneous measurements of voiding cysto-urethrography and urodynamic studies using the Life-Tech 6 channel polygraph in 35 patients (17 patients with PFUS and 18 patients with PUR). RESULTS: The prevalence in ages revealed two peaks, 20 years and 50 to 60 years. Over 25% of them had pyuria more than 10/hpf of WBC. Peak flow rate measured by uroflowmetry showed normal range in PFUS group and decreased in PUR group. The functional vesical volume was less than 100 ml in most patients with PFUS. Residual urine in PUR group was significantly greater. Capacity of the PFUS group were able to hold over 400 ml of contrast instilled through the urethral catheter, despite increased desire to void. Over 15% of the study group with PFUS showed uninhibited systolic contraction of detrusor (> 15 cm H2O) during filling phase. The measurement value of urodynamic parameters demonstrated that a periodic follow-up survey of the upper urinary tract should be performed because of the low compliance bladder in the patients with PLUTD. During voiding phase, the women with PFUS had a tendency to be divided into two groups, hypercontractile or acontractile detrusor. The voiding cysto-urethrography (VCUG) showed a tendency of bladder neck opening on patients with PFUS during filling phase. Most of PLUTD cases demonstrated a round to triangle shape on vesical configuration, which led to a spastic condition of detrusor muscle. We attempted to measure the quantitative perspiration using 3 kinds of loading tests; respiratory, arithmetic and psychological load. In the psychological loading test, we asked 98 questions about their daily lives including occupation, living condition, family relationship and sexual activities. Arithmetic loading test consisted of counting in reverse, subtraction and multiplication. The quantitative perspiration rate resulted in a "positive" in many patients with PFUS. Respiration loading test was performed to measure the respiration volume during 3 large inhales. Most patients with PUR tested within the normal range for respiration except for those patients with decreased or no perspiration during the psychiatric loading test. These results may reflect the psychological elements including suppression and subconscious defense mechanism. Neurosis which was diagnosed as having type III to type IV of the Cornell Medical Index was demonstrated in less than under 40% of patients with PFUS and more than 55% patients with PUR. There was no significant trend or difference between PFUS and PUR detected from Todai's Egogram. CONCLUSIONS: Due to the reflection of many psychological responses, it is necessary to investigate from various examinations including psychological, autonomical and classical urological studies for accurate diagnosis of PLUTD. 相似文献
86.
Komatsu K Bamba N Komota S Sato H Fuse M Nakamura N Kimura K 《Masui. The Japanese journal of anesthesiology》1999,48(3):301-303
We could perform endotracheal intubation in three patients whose ventilation had been anticipated possible preoperatively but endotracheal intubation impossible, using a fiberoptic bronchoscope while ventilating via Patil-Syracuse mask. This method is an alternative in a "can ventilate/cannot intubate" situation. 相似文献
87.
Moizumi Y Komatsu T Nagaya K Sawamura Y Sakurai M Tabayashi K 《The Journal of cardiovascular surgery》1999,40(1):117-119
We report a rare case of a 39-year-old man with type A aortic dissection involving a right-sided aortic arch with the symptom of vascular ring. Computed tomography scanning and angiography were performed to define the extent of the dissection and the anatomy of the branching vessels. The ascending aorta was replaced through a median sternotomy and right thoracotomy using a hypothermic cardiopulmonary bypass associated with selective cerebral perfusion and partial circulatory arrest, and his symptom of vascular ring disappeared postoperatively. 相似文献
88.
89.
Kitada M Mizoguchi A Tohyama K Ohtsubo A Fujimoto E Chakrabortty S Ide C 《Restorative neurology and neuroscience》1999,14(4):251-263
Axonal and glial reactions to traumatic injury were compared between the caudal and rostral border of the lesion after freeze-injury to the C3 dorsal funiculus by attaching a liquid nitrogen-cooled copper probe to the dorsum of the rat spinal cord. The axonal and glial changes were examined up to 60 days postoperative by light and electron microscopy and immunohistochemistry for neurofilaments. Regenerative axonal changes and the appearance of numerous undifferentiated cells were found at the caudal border 7 days after cryoinjury. In contrast, such axonal and cellular reactions were scarce at the rostral border. Undifferentiated cells clearly manifested their phenotypes by differentiating into oligodendrocytes or astrocytes 11 days postinjury. The results indicated that glial cell reactions occurred in association with regenerative axonal changes at the proximal stump of the injured nerve fibers, suggesting that regenerating and demyelinated naked axons could be responsible for the appearance of the immature glial cells. 相似文献
90.
The analgesia-producing mechanism of processed Aconiti tuber was examined using rodents whose nociceptive threshold was decreased by loading repeated cold stress (RCS). The antinociceptive effect of processed Aconiti tuber (0.3 g/kg, p.o.) in RCS-loaded mice was antagonized by pretreatment with a kappa-opioid antagonist, nor-binaltorphimine (10 mg/kg, s.c.), and was abolished by an intrathecal injection of anti-dynorphin antiserum (5 microg). The Aconiti tuber-induced antinociception was inhibited by both dexamethasone (0.4 mg/kg, i.p.) and a dopamine D2 antagonist, sulpiride (10 mg/kg, i.p.), in RCS-loaded mice, and it was eliminated by both an electric lesion of the hypothalamic arcuate nucleus (HARN) and a highly selective dopamine D2 antagonist, eticlopride (0.05 microg), administered into the HARN in RCS-loaded rats. These results suggest that the analgesic effect of processed Aconiti tuber was produced via the stimulation of kappa-opioid receptors by dynorphin released in the spinal cord. It was also shown that dopamine D2 receptors in the HARN were involved in the expression of the analgesic activity of processed Aconiti tuber. 相似文献